1

Extension Bulletin on Soil Science

Rajan Bhatt and Manoj Sharma

Krishi Vigyan Kendra,

Kapurthala

DIRECTORATE OF EXTENSION EDUCATION

PUNJAB AGRICULTURAL UNIVERSITY

LUDHIANA -- 141001

INDEX

2

Chapter no Title of the Chapter Page no.Chapter 1 Techniques of soil sampling and interpretation

of it’s results3 - 4

Chapter 2 Performance of Soil and water testing Labortary of Krishi Vigyan Kendra, Kapurthala from 2006 to upto June 2010

5 - 8

Chapter 3 Importance and determination of Soil Texture in relation to soil fertility

9 - 14

Chapter 4 Role of organic manures to maintain soil health and fertility

15 - 23

Chapter 5 Identification and amelioration of micro-nutrients in rice-wheat cropping system

24 - 29

Chapter 6 Balanced Nutrition for Sustainable Crop Production In India

30 - 33

Chapter 7 Green Manuring in relation to the soil fertility

and soil health

34 - 38

Chapter 8 Laser Leveller for precision land levelling for judicious use of water in Punjab

39 - 47

Chapter 9 Water resource management for sustainable crop production in India

48 - 53

Chapter 10 Improving the soil health 54 - 55

Chapter 11 Increasing production in waste land and degraded fallow lands: Need of hour

56 - 59

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Chapter 1

Techniques of soil sampling and interpretation of it’s results

Rajan BhattAssistant Professor (Soil Scinece)Krishi Vigyan Kendra,Kapurthala

rajanbhatt79@rediffmail.com(98159-63858)

Soil Testing-Need Of The Present Farming

Fertilization according to the soil test results have been recognized as one of the most

reliable option to ensure balanced nutrition to the crops. Generally, the farmers found it most

difficult to know the proper type of soil management practice, which would match his soil

condition. Farmers do not take into account the requirements of his crop and the

characteristics of soil. Soil varies widely in its chemical composition depending upon the

fertilizer management by the individual farmer and the parent material from which it is

originated. Soil characteristics also vary significantly from one place to another, even in a

small field. So, the quantity, kind and type of fertilizer required even for the same crop vary

from soil to soil, even field to field on the same soil. The success of soil testing for fertilizer

recommendation depends exclusively on the collection of representative soil sample from a

field.

Technique Of Soil Sample Collection

Soil testing is the only way to determine the fertilizer needs of a crop in a particular field. Soil

test is the analysis of soil sample to determine the available nutrient status and physico-chemical

properties of soil. The prime step in the soil-testing programme is the collection of soil sample. The

fertilizer recommendations for the field crop are generally given on the basis of only a small amount

of soil used in the laboratories. Actually, the one to ten grams of soil used for each chemical analysis

should represents as accurately as possible the entire six inches (top six inches) of soil, weighing

about one million kilogram per acre.

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Technique to collect soil sample for orchard plantation

Therefore, it is important that soil samples should be a true representative of the field. Soil

sampling for fertilizer recommendation for the field crops is performed up to a depth of top six inches

because the top six inch soil is the area that has the majority of the root activity and secondly the

fertilizer application and cultivation operations are mainly confined to this depth. While taking the

sample, the surface litter (if any) is removed with a trowel or spade and the soil is collected from the

surface to plough depth (0-6 inches) from 8-9 random spots in a field by giving ‘V’ shape incision. A

uniform 2.5cm thick slice of soil from top to bottom (6 inch depth) is removed and collected in a

clean bucket or wide container. To obtain a representative sample from bulk soil collected from

different spots, the soil is poured from bucket or to a piece of clean cloth or paper and is mixed

thoroughly. Quartering is then performed to reduce the soil to about 500 g. Quartering is done by

mixing sample well, dividing it into 4 equal parts, then rejecting two opposite quarters, mixing the

remaining two portions, again dividing into 4 equal parts and rejecting two opposite quarters, and so

on. If the soil sample is wet it may be air dried in the shade before packing it in the cloth bag. Care

should be taken to avoid soil sampling from unusual areas viz. recently fertilized, old bunds, marshy

spots, under the trees, composed pits etc. The cloth bag should be properly marked to identify soil

sample. The information sheet encompassing the information like name and address of farmer, depth

of soil sampling, crop rotation, irrigation facility, crop history, the fertilizer applied to the previous

crop etc. should be enclosed in the cloth bag.

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Chapter 2

Performance of Soil and water testing Labortary of Krishi Vigyan Kendra, Kapurthala from 2006 to upto June 2010

Table no 1. No. of Soils and water samples analyzed by soil and water testing labortary of KVK, Kapurthala.

Year No of soil and water samples analyzed by the Soil and water testing Lab of KVK., Kapurthala.

Amount obtained and submitted after analysing the samples @Rs 20 per sample

2005 Nil Nil

2006 152 3040 = 00

2007 292 5840 = 00

2008 381 7620 = 00

Upto June 2009 455 9100 = 00

Upto June 2010 460 9200 = 00

Total 1740 34,800 = 00

Fig: Graphical representation of performance of soil laboratory from 2006 to June 2010

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2006 2007 2008 Upto June 2009

Upto June 2010

050

100150200250300350400450500

152

292

381

455 460

ky vI ky dI im`tI Aqy pwxI prK lyborytrI dI kwrgujwrI

swl

n

rIK

x k

Iqy n

mU

ny

Table no 2. No. of Soils and water samples analyzed by soil and water testing labortary of KVK, Kapurthala free of cost

Sr. No. Year Crop/Scheme Samples analysed free

of cost

1. 2006-07 Under Front line demonstrations viz.Gram,Gobhi-Sarson, Sunflower,Neem coated urea, For preparing the fertility map of KVK instrauctional farm.

136

2. 2007-08 Adaptive trials, Neem coated urea, Under Front line demonstrations viz.Gobhi-sarson,Gram,

139

7

SunflowerGroundnut, moong, Adopted village Blairkhanpur

3. 2008-09 Under Front line demonstrations viz. Sunflower, Gram (GPF-2),Gobhi-sarson,

38

4. 2009-10 Under Front line demonstrations viz. Sunflower, Gobhi-sarson, Gram (PBG-5))

40

Total samples analysed free of cost 353

Table No. 3 Total number of soil and water samples analysed (By charging fee and free of cost) from 2006 to june 2010.

Sr. No. Soil and water samples

analysed

Samples analysed free of cost

1. Free of cost under Front line Demonstartion plots or under adaptive trials

353

2. Samples analysed by charging fee for analysis @Rs 20 per sample

1740

Total samples analysed free of cost 2093

Soil and water testing laboratory is well functioning at KVK, Kapurthala. Starting from the

functioning of the lab to upto now we had analysed 1740/- samples (Soil and water) and thus submit

Rs. 34,800 = 00 to the higher quarters by charging Rs. 20 per sample as analysing fee from the

farmer. Instead of this, before conducting any FLD or any research trial, the soil samples of

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demonstration plots are analyzed for knowing it’s inherent soil fertility viz. pH, EC, Soil texture, O.C

(%), K (Kg/ha) and P (Kg/ha free of cost and fertilizer recommendations are made accordingly and in

this regard upto now analyse 353 soil samples free of cost for knowing the inherent fertility of the

selected plot. Thus, a total of 2093 samples were analysed by this lab so far. We had also prepared the

Soil Fertility Map of KVK instructional farm after analyzing 100 soil samples (20 samples from 5

blocks). In addition, 100 samples of adopted village viz. Blerkhanpur were analyzed free of cost. Soil

testing so far revealed that potash is now becoming to be a deficient nutrient in most of our soils

because of the continue removal of this nutrient in our paddy-wheat cropping system. Organic carbon

in 95% samples is in low range (<0.4%). As far phosphorus is concerned, it is observed that 75%

samples fell into low phosphorous category (available potash <5 kg/acre) and 25% came in the

medium range (available potash 5-9 kg/acre). Further, it is analysed that 60% of the soil samples of

the farmers, whereas 74% of the selected Front Line Demonstration Plots were low in potash.

Thus, inherent fertility of soils is declining day by day.

*******

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Chapter 3

Importance and determination of Soil Texture in relation to soil fertility

Rajan BhattAssistant Professor (Soil Scinece)Krishi Vigyan Kendra,Kapurthala

rajanbhatt79@rediffmail.com(98159-63858)

Soil comprises of the three important primary partners, viz. sand (2-0.02 mm), silt (0.02-0.002 mm)

and clay (<0.002 mm). These primary particles are generally clustered together to form secondary

particles or aggregates which further binds together with organic matter and some other materials in

different proportions to form different types of the soils viz. loamy soil has 40% sand , 40% silt and

around 20% clay. Sand feels gritty between fingers and the particles are generally visible to the naked

eye. As sand particles are relatively large, the bigger pores in between them promote easy drainage of

water into and out of soil profile and exchange of gases with the atmosphere. Silt particles are smooth,

silky like flour. The pores between them are smaller and many, thereby retaining water for a longer

period of time. The clay particles have a very large specific surface area and have a tremendous

capacity to adsorb water and other substances and make the soil sticky or plastic.

Importance

The mechanism of water infiltration, retention in soil and drainage out of the root zone are a

phenomenon associated with soil texture. The coarseness of fineness of soil determines the

rates of these processes and hence water availability to the plants.

The structure of soil, an important parameter determining the physical fertility of soil is a

function of soil texture. The fine textured soils have a more stable structure but a plenty of

micropores, which help retain more water and less air in the soil, but coarse-textured soils

have more macropores, which conduct water very fast.

Soils with finer particles get waterlogged during excessive rains or irrigation and result in

aeration stress to plants with the result that they are not able to take up water and nutrients,

which are present in the soil in sufficient quantities.

The fine-textured soils help in retaining more nutrients on their surfaces through adsorption

and hence lesser losses through leaching etc. The cation exchange capacity of soils, which is

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very important in determining the availability of nutrients to plants, is a function of soil

texture.

The workability of the soils is a direct function of soil texture. In fact, the heavy or light

texture means the force required at drawbar during cultivation.

The erodibilty of soil-resistance of soil towards the erosion process is also a function of soil

texture.

In fact most of the soil physical and chemical properties are a function of soil texture either

directly or indirectly.

Relation with soil fertility

Since weathering takes place at the surface of mineral particles, releasing constituent elements

into the soil solution depends upon the surface area of the minerals. Greater the surface area,

the greater the rate of release of plant nutrients from weathering minerals.

The retention of nutrients and water on the soil solids is a function of surface area of the clay

minerals. Also the leaching of nutrients is a function of soil texture. Thus finer soils tend to be

more fertile than the coarse textured ones.

The fertility of soil being a function of soil moisture, fine textured soils, which retain more

water for a longer period of time, are more fertile than the coarse textured soils. At the same

time a balance between soil moisture and soil air is a must for better uptake of nutrients. Soils

with appreciable amounts of different primary particles are more fertile.

Soil fertility is maintained through various chemical reactions in the soil, which are

influenced by microorganisms. These tend to grow and colonize particle surfaces. Microbial

reactions are thus greatly affected by the specific surface area.

Methods of determination

Feel method

International pipette method

Hydrometer method

The feel method is a crude method by which we are able to judge broadly the classes of soil texture

viz. sandy loam, loamy sand, silty loam, clay loam etc. The experience of the person matters in

accurately judging the texture.

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The pipette method involves the dispersion of soil sample into ultimate particles and then separating

the coarse sand particle through sieving and fine through sedimentation, which is based on Stoke’s

law. The differential settling of particles is a function of their size. The bigger particles settle first,

followed by smaller particles. The sample of soil-water suspension taken after a certain pre-calculated

time corresponding to a particular size group of particles, may contain those particles and after drying

the sample at 105oC, the percentage of that group of particles can be found out.

The hydrometer method also involves dispersion of soil into primary particles, sieving coarse sand

particles and subsequently the differential settling of particles. But instead of actually taking a sample

for different fractions, this method is based on the measurement of density of soil-water suspension at

different times and relates it with the particle size groups. A hydrometer reading at 4 minutes means

measuring density for silt and clay particles and that at 2 hours means density for clay particles at a

temperature of 68oF. At temperatures above and below this value needs temperature correction in the

hydrometer readings.

For determining the texture of a soil, the relative proportion of different primary particles

(sand, silt and clay) needs to be found out and procedure is called Particle size analysis. It is

an index of physical and chemical properties of soils. The methods used for this analysis are

Pipette method and Hydeometer method. Both these methods are based on Stoke’s law for

the fractionation of finer particles but differ in the mode of recording. Pipette method is

laborious and time consuming whereas hydrometer method is simple and rapid.

Procedure

The particle size analysis by Hydrometer method involves two important steps: dispersion

and fractionation of soil particles.

Dispersion

Take 50 g of 2-mm sieved oven-dry soil in a 500 ml beaker.

Add 20 ml of H2O2 solution into it and swirl the contents well and place it on a hot

plate. Continue digestion, stirring the contents all the time with a glass rod to

minimize frothing, till the reaction completely subsides. Cool the beaker.

Detach the soil particles from the inner sides of the beaker by rubbing with a

policeman and with a jet of distilled water.

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Add 25 ml of 2N HCl solution and allow the contents to react for an hour. Filter the

contents through a Whatman No. 50 filter paper and discard the filtrate. Wash the soil

with distilled water till the filtrate is free from chlorides.

Transfer the soil from filter paper to a 500 ml beaker with a jet of distilled water.

Make the volume to 300-350 ml with distilled water and add a few drops of

phenolphthalein indicator. Add N/10 NaOH solution till the whole suspension shows

a pink colour and stir the contents of the beaker with an electric stirrer for 5-10

minutes.

Fractionation

Transfer the contents of the beaker to a 1-litre cylinder of standard dimensions and

make the volume to 1 liter. Place the cylinders in a controlled temperature room at

68oF (otherwise note down the temperature of the suspension and correct the

subsequent hydrometer readings for this temperature).

Shake the suspension with a plunger for 20-25 times or till all the soil particles come

into suspension. Take the hydrometer readings at 4 minutes and 2 hours for silt + clay

and clay, respectively as shown below.

Carefully put the hydrometer in the suspension 30 seconds before the actual timing

and let it become stable. Note down the hydrometer reading at 4 minutes after the

plunger was taken out of the suspension. Take the hydrometer out of

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suspension and wash it with distilled water and take reading at 2 hours after the

plunger was taken out of the suspension.

In case the temperature of the suspension could not be maintained at 68oF, add 0.2 to

the reading for each degree above 68oF and subtract 0.2 for each degree below 68oF

within 60 to 75oF.

Determination of soil textural class

The texture of soil is determined from the relative proportions of sand, silt and clay

that it contains. Triangular classification suggested by ISSS is in common use. It makes use

of an isolateral triangle whose area is divided into 12 compartments each representing a

texture. The differences between the two are primarily due to differences in size ranges of

sand and silt fractions. For the determination of the texture of a soil, locate the clay and silt

%ages on the respective sides of a triangle. Draw a line parallel to the sand axis in the former

case and to the clay axis in the later case. The compartment in which the two lines intersect is

the texture of the soil.

Soil fertility management tips

1. Must apply fertilizers as per the soil testing report.

2. Go for green manuring after wheat preferably with cowpea and sun-hemp. Green

manuring with Dhaincha crop is somewhat discouraged because of it’s high water

demand and sensitivity toward attack of insect-pests which further required

insecticides spray. However, green manuring with moong preferably var. SML-668

(Sathi moongi-as it took around 60 days) because moong crop roots had nodules

having rhizobium bacteria which further fixes atmospheric nitrogen in soil. Inspite of

increasing the inherent soil fertility, moong grains provides an extra income to the

farmer.

3. Apply well rotten farm yard manure to fields @7 -10 t ha-1.

4. Apply urea as per leaf colour chart because higher dose of urea invites more attacks of

insects-pests where by applying urea as per LCC we apply urea as per crop demand.

5. Shifting of the cropping pattern from wheat-paddy to wheat- maize as on one side it

will improves the soil health and on other hand uplifts the declining water table as

maize water requirements is quite low as compared to the paddy.

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-------------------------------------------=------------------------=----------------------

Chapter 4

Role of organic manures to maintain soil health and fertility

15

Rajan Bhatt,Assistant Professor (Soil Science),

KVK Kapurthalarajanbhatt79@rediffmail.com,

Soil fertility in relation to Bulky organic manure: Under this title are included

1. Farm yard manure (FYM)

2. Town compost

3. Night soil

4. Sewage and sludge

A) Farm yard manure (FYM):::

India maintains nearly 1/3rd of the world’s animal population and nearly 1/3rd of the Fram yard

manure is utilized as manure and most of this is being used for cooking the food. The term FYM

refers to the decomposed mixture of dung and urine of farm animals along with the litter (Bedding

Material) and left over material from the fodder fed to the cattles. FYM collected daily from the cattle

shed mainly consist of dung and urine soaked bedding material. FYM mainly contains about 0.5 % N,

0.2 % P2O5 and 0.5 % K2O. For century this has been used as manure in the field. Unfortunately,

now a days around 50 % of cattle dung has been used as fuel and is thus is a lost to agriculture.

Table :1 Chemical composition of fresh excreta of animals

Excreta of Percentage of

N P2O5 K2O

Cows and

bullocks

Dung 0.40 0.20 0.10

Urine 1.00 Traces 1.35

Sheep and

Goats

Dung 0.75 0.50 0.45

Urine 1.35 0.05 2.10

Horses Dung 0.55 0.30 0.40

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Urine 1.35 Traces 1.25

Pigs Dung 0.55 0.50 0.40

Urine 0.40 0.10 0.45

Thus, urine of all animals contains more percentage of nitrogen, and potash, compared to the dung

portion.

Table 2: Approximately quantity of dung and urine produced per head annually

Animals Dung produced per year

(Cartload)

Urine produced per year

(Kerosene tina)

Bullocks 15.1 162

Cows 11.2 121

Sheep 0.8 10

Horses 20.1 126

Pigs 1.5 25

*Cartload carries about 1000 pounds of dung and one kerosene tin contains about 40

pounds of urine.Horses produced the maximum amount of nitrogen, phosphorus and

potassium in their dung and urine.

Dr. R.R.Agarwal has listed the following reasons for a small proportion of the potential manorial reesourcees of the country being actually

utilized as manure.

1. A large proportion of the cattle dung is dropped outside the cattle shed while grazing.

2. A large proportion of the dung is dried into dung cakes for cooking as a fuel.

3. The urine (Liquid protion) is not properly conserved.

4. There is improper and wasteful fermentation of the manure.

5. Leaching during the rains and drying the hot months in roadside heaps causes considerable loss of the nutrients.

Improved method of handling the Farmyard manure

Trench method:

Dr. C. N Acharya recommends this method. Manure preparation should be done in the trench of

suitable size, say 20 to 25 ft long, 5 to 6 ft broad and 3 to 3.5 ft deep. All available dry litter and

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refuse from the farm and the house should be heaped up near the cattle-shed and portions of the litter

mixed with earth if available, should be spread in the shed in the evening, at the rate of 5 lb per animal

for the absorption of urine. The litter should be localized in the areas where urine generally drops and

soaks into the ground. Each morning, the urine soaked litter and dung should be well mixed and taken

to the manure trench. The trench is filled up by first taking 3ft into account and then next three ft.

When, the trench is filled in say about three months, then dug out another pit for filling. The manure

in the first pit is prepared in about three months which can be used directly for application to the land

and the similarly pit is used for preparing other manure.

Factors influencing the composition of the manure:

Following factors affect the composition of the manure

Source of the manure

Food of the animal

Agee and condition of the animal

Function of the animal

Manner of storage

Nature of the litter

Table 3: Percentage of different nutrients in straws normally fed to animals

Straw or stalks

Percentage of different nutrients

N P2O5 K2O

Paddy 0.36 0.08 0.71

Wheat 0.53 0.10 1.10

Jowar 0.40 0.23 2.17

Maize 0.42 1.57 1.65

Bajra 0.65 0.75 2.50

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Losses during handling and storage of FYM

A. Losses during handling: FYM consist of dung and urine portion. Approximately half of

nitrogen and potash is in the dung and other half is in the urine portion whereas around 96% of

the phosphorus is in the solid portion.

1. Loss in the urine portion: Under Indian conditions, the kachha floor is unable to

conserve the liquid portion. Large quantities of the nitrogen are thus lost through the

formation of gaseous ammonia. Following reaction takes place

CO(NH2)2 + 2H2O = (NH4)2CO3

(Urea in urine) (Ammonium carbonate)

2. Loss in the solid portion: Mostly through the burning of the cakes for the cooking

purpose and secondly large quantity of the dung is dropped while grazing outside

collection of which is not possible.

B. Losses in handing: Mainly through leaching, for which the water must has to pass through the

manure and secondly through volatilization of the ammonia and it’s compounds.

Proper field management: Normally the farmers adopt following two practices

1. Mostly, the farmers unload the FYM in small pits in their field before spreading which is left

as such for a month or more.

2. Mostly, the farmers often plough the FYM in their fields after a few days of spreading.

However, both of these practices are faulty and lead to the loss of the nutrients through the

heating and drying. Thus, it is suggested to spreading and immediately mixing the FYM in the

soil for getting the maximum benefit out of it.

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Use of the chemicals as a preservative is also found to have an effect on the loss of the nitrogen.

Among different preservatives Gypsum and Superphosphate are the important one. It is

recommended that one to two pounds of single superphosphate should be applied per day par

animal in the cattle shed, preferably at places where the urine mostly passed.

B) Compost from farm and town refuse:

Composting is mainly a biological process, in which microorganisms of both aerobic and non-

aerobic type decompose the organic matter and lowers the C/N ratio. The final product is the well

rotten manure known as compost. Because of having more organic matter and adding more plant

nutrients into the soil, the compost plays a significant role in improving and maintaining the soil

fertility as compared to the FYM. Normally, the following types of the compost are prepared in

India.

Compost from the farm litter:

Under this category, weeds, stubble, bhusa, sugarcane trash etc. are converted into the compost

manure on the farm itself.

Method of composting:

A trench of suitable size around 15 to 20 ft long, 5 to 6 ft broad and 3 to 36 ft deep is dung for

preparation of the compost. About 1 ft thick layer of refuse is spread all along the whole length of the

trench which was well moistened by sprinkling the mixture of the cowdung + water or earth + water.

Add the refuse in trench till the heap rises to a height of around 1 to 2 ft height. Top of this is covered

by the thin layer of earth. After three months of the decomposition, the entire mass is heaped in a

conical form above the ground and moistened with water if necessary and covered with earth. After

one two months the compost is ready to use in the fields. Thus a total of 4-5 months is required to

prepare the compost through this method. This compost mainly contains about 0.5 % N, 0.15 % P2O5

and 0.5 % K2O.

Compost from the town refuses:

Town refuse mainly contains night soil, sewage, sludge, street and dustbin refuse.This refuse

can be converted into the good quality manure by adopting Banglore method of compost

Banglore Method of compost preparation:

Trench of suitable size made according to the population size as shown in the table 4. Site must be

atleast two furlongs away from the town and should not made on the western side of the town as the

wind generally flows from the west to east for most part of the year.

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Table 4: Population wise dimensions of the trench for compost preparation (Banglore method)

Size of the trench (ft)

Population Length Breadth Width

<5,000 15 5 2.5

5,000-10,000 20 6 3

10,000-20,000 25 6 3

20,000-50,000 30 7 3

>50,000 30 8 3.5

Trenches should be so arranged that the longer sides are parallel and the shorter sides are in the same

line by keeping around 5 to 7 ft space in between the trenches.

First, a layer of KATCHRA about 6 inches thick is spread on the bottom of the trench, with long

handled rackes. Over this add around 2 inches of the night soil, which is spread over the previous

material. Thus the layer of kachra and night soil added alternately. At the end of each day, the katchra

is added to a height of around 9 inches. Loose earth may be used to cover the top of heap around 2

inches height. This thick layer effectively checks the foul smell, conserve the moisture, avoid nitrogen

losses and minimizes nuisance of the flies. Trench on coming to the ground level, is filled with kachra

and earth, so that it rises one ft above ground level. In the rainy season, it is preferred to made the top

in dome shaped, so that rainwater will not enter into the trench and flows out. In about 3 to 4 months,

the manure is fully prepared for it’s application to the land. This compost mainly contains about 1.4

% N, 1.0 % P2O5 and 1.4 % K2O.

Advantages of the Banglore method: It manily

1. Kills weeds

2. Control foul smell

3. Highly hygienic and sanitary.

4. Avoids nitrogen losses

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5. Can be installed few furlongs away from the town.

C) Night Soil:

Simply it is human excreta i.e. both solid and liquid. In China, from thousand of years, it is applied to

the soil for maintaining the fertility of the soil. Night soil is richer in nutrients as compared to the

FYM and compost. On oven dry basis, it has an average chemical composition of:

5.5 % N, 4.0 % P2O5 and 2.0 % K2O.

Poudrette System:

Trench of 10 to 12 ft long, 2 to 3 ft wide and 9 inches to 1 ft deep are made. In these trenches, night

soil is deposited and covered over on top with a layer of earth or Kachra. The material obtained from

this trenches are as “Poudrette” on drying. However, mixing the night soil with an equal amount of

the ash and 10 % powdered charcoal produces an odorless material containing 1.32 % nitrogen, 2.8 %

Phosphoric acid, 4.1 % Potash and 24.2 % lime.

Drawbacks of the poudrette system:

Following are the some of the drawback of thee poudrette system:

1. Gives out lot of bad smell.

2. Leads to fly breeding

3. Special class of “Bhangi” Are to be employed.

4. Quantity of the produced manure is small as compared to the FYM and compost.

5. Large losses of the nitrogen are there.

Improved method of handling:

1. It should be protected from the flies.

2. It should not pollute the drinking water.

3. Attempt should be made to compost the night soil with other refuse.

4. Pathogens, protozoa cysts, worms and eggs should be destroyed.

D) Sewage and sludge:

In general sewage has two components,

Solid portion, technically known as sludge

22

Liquid portion, technically known as the sewage water.

Both of these are used in increasing the crop production as it contains the plant nutrients however, the

use of untreated water is not recommended. In the treatment, both the components are separated and

are given a preliminary fermentation and oxidation treatments to reduce the bacterial contamination,

the offensive smell and also to narrow down the C: N ratio of thee solid portion.

1) Sludge: Solid portion is separated out and given the preliminary treatment before to

used as a manure for which it is stored in a septic tank to relieve it of the heavier portion of the solid

matter also to undergo a preliminary fermentation and oxidation of the organic matter in the fresh

sewage, thereby reducing the C: N ratio. Such a material is known as the “Activated Sludge” is of

inoffensive small and on dry weight basis contains up to 3 to 6 % Nitrogen, about 2 % phosphorus

and 1 % potassium in a from the can become readily available when applied to the soil. A number of

sludge methods are produced by thee different methods of sewage treatment or preparation in

different countries

Settled Sludge, produced by plain sedimentation

Digested sludge, resulting from anaerobic decomposition of sedimented sludge.

Activated Sludge

Digested activated sludge

Chemically precipitated sludge

Sludge, in general rich in nitrogen and phosphorus while they are low in potash. Thee

principle value of the sludge as a manure lies in their slowly available nitrogen and phosphorus.

Sludge also act as a source of micronutrients such as Boron, Manganese, Copper, Zinc and Iron.

2.) Sewage irrigation: After removing the sludge, the water is used, as a source of

irrigation is known as “Sewage Irrigation” which also supplies N, P and K. The effluents from thee

settling tanks with only anaerobic fermentation treatment, still carries a large amount of thee

objectionable colloidal matter. However with the aerobic oxidation, the treated effluents as it is called,

is a clear odorless liquid containing nitrate in solution through which large no. Of pathogenic bacteria

has been removed.

23

Thus, both the activated sludge and the effluent can be used with safely for manuring and irrigating all

the field crops except the vegetables, which are eaten raw or uncooked.

Commonly raised crops with irrigation water:

Fodder ops like Oats, Jowar, Maize, Berseem and Lucern.

Sugarcane

Vegetable crops like Cabbage, cauliflower, turnip, potato, bringal, Lady’s finger etc.

Irrigating with the sewage water is not advocated safe for raising all the crops. In general, products

which can be consumed raw mainly tomato, onion, garlic and carrot should not raised by irrigating

with the sewage water because of danger of spreading thee disease.

Thus , we can upgrade the health of our soil by using the above mentioned awys

buit the method of preparation should be correct band it is used at the exact

amount which is proposed for a particular type of the soil.

Chapter 5

IDENTIFICATION AND AMELIORATION OF MICRO-NUTRIENTS IN RICE-WHEAT CROPPING SYSTEM

Rajan Bhatt

24

Assistant Professor (Soil Scinece)Krishi Vigyan Kendra,Kapurthala

rajanbhatt79@rediffmail.com(98159-63858)

Plants require about sixteen nutrients for normal growth and to complete their life

cycle. They are carbon, hydrogen, oxygen, nitrogen, phosphorus, potassium, sulphur, calcium,

magnesium, boron, molybdenum, chlorine, zinc, copper, iron and manganese. Among them carbon,

hydrogen and oxygen are absorbed by plants from air and water, while all other nutrients are absorbed

by plants from soil. Nitrogen, phosphorus and potassium are required by plants in large amounts,

therefore they are referred as major nutrients. Sulphur, calcium and magnesium are refereed as

secondary nutrients. The remaining (boron, molybdenum, chlorine, zinc, copper, iron and manganese)

nutrients are referred as micro nutrients. They are micro in the sense that they are required by plants in

very small amounts in comparison to major nutrients, but not in the sense of their minor importance in

plant life. Although they are present in minute quantities in soil, but they are as important for plants as

the macro nutrients are. Their deficiency in plants may leads to reduction in crop yields to greater

extent.

Intensive cropping (cropping intensity 188%) coupled with the use high analysis

macro nutrient fertilizers over the last few decades has resulted in the deficiency of several essential

micro nutrients in Punjab soils. According to the recent reports about 25, 10, 3 and 2 per cent soils of

the state are deficient in available zinc, iron, manganese and copper. Among these essential micro

nutrients the deficiency of zinc, iron and manganese has been seen on different crops in Punjab.

Deficiency of zinc in widespread and is encountered under varying soils and crop situations, while the

deficiency of iron and manganese is location and crop specific. Rice-wheat is the major cropping

system in Punjab, and is very exhaustive in nature. Therefore, the micro nutrients deficiencies which

affect these crops are discussed below.

SOILS PRONE TO MICRO NUTRIENT DEFICIENCIES

Zinc: Zinc deficiency is generally encountered in fields with coarse textured soils, low organic

matter, high pH, high calcium carbonate. Use of irrigation water containing high amounts of

bicarbonates and excessive use of phosphatic fertilizers can also leads to zinc deficiency in soils. The

25

soils of floodplain areas and recently leveled soils are also prone to zinc deficiency. Soils testing less

than 0.6 kg zinc/kg soil are rated as zinc deficient soils.

Iron: Iron deficiency is common in soils with coarse texture, low organic matter, high pH, high

calcium carbonate content. Soils testing less than 4.5 mg iron/ kg soil are rated as iron deficient soils.

Iron deficiency is conspicuous in rice grown on sandy soils which are unable to pond water for longer

period due to very high permeability.

Manganese: Manganese deficiency is common in soils with coarse texture, low organic matter,

high pH. Sandy soils under rice-wheat cropping sequence for last 6-7 years show manganese

deficiency. Owing to flooding conditions developed during rice season, a part of manganese gets

leached to the lower soil layers. As a consequence of that, the content of available manganese in the

surface layer of soil reaches a level that is inadequate to meet the manganese requirement of wheat

crop following rice. Soils testing less than 3.5 mg manganese/kg soil are rated as manganese deficient

soils.

VISUAL DEFICIECY SYMPTOMS AND AMELIORATION

RICE:

26

Zinc deficiency symptoms: Zinc deficiency in rice plants first appears on lower (old) leaves at

about two-three weeks after transplanting the crop. Deficiency appears as light yellowish brown spots

scattered in the interveinal areas imparting pale yellowish-brown color to the affected leaves. With the

passage of time these spots enlarge, join together and become reddish brown or rusty in color. Under

acute zinc deficient conditions, the plants give rusty look (Fig. 1). The affected leaves finally dry up

and fall or float on water. The growth of plants under deficient situations is reduced and they give

bushy appearance. Tillers fail to develop panicles and results in reduction in grain yield. Under acute

deficient conditions, earing and maturity are delayed.

Fig.1. Zinc deficiency symptoms in Rice

Amelioration: Zinc deficiency can be corrected by applying 25 kg zinc sulphate heptahydrate (21%

Zn) or 16 kg zinc sulphate monohydrate (33% Zn) per acre by broadcast method at the time of crop

transplanting.

Iron deficiency symptoms: Iron deficiency symptoms are exhibited as interveinal chlorosis of the

younger or newly emerging leaves. Soon after, the veins also lose green color and whole leaf turns

yellow in color. Under acute iron deficient conditions, there is a bleaching of the affected leaves and

the newly emerging leaves also look white or bleached (Fig. 2).

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Fig 2 Iron deficiency in paddy

Amelioration: Iron deficiency can be ameliorated by foliar application of 1.0% ferrous sulphate

solution, 2-3 times at weekly interval.

WHEAT:

Manganese deficiency symptoms: In wheat deficiency of manganese may appear at two stages

i.e. at initial growth stage just after the first irrigation to crop and later at ear emergence stage.

Manganese deficiency symptoms during the early growth stage of wheat appears immediately after

first irrigation to crop. Deficiency symptoms are manifested as interveinal chlorosis on the middle

leaves, with light grayish yellow to pinkish brown or buff colored specks of variable size confined

largely to 2/3 lower portion of the leaf. With the passage of time, these spots enlarge and join together

to form streaks or band in between the veins which remain green (Fig. 3). In case of acute manganese

deficiency, whole plant may become dry and crop gives a burning look. At head emergence stage,

these symptoms appear prominently on the flag leaf. Wheat crop in such deficient situations also

experience a great difficulty at the time of ear emergence. The emerged ears remained week and

deformed.

Fig.3 Manganese deficiency in wheat.

Amelioration: Manganese deficiency can be corrected through foliar application of manganese

sulphate solution. In manganese deficient soils, give one spray of 0.5% manganese sulphate solution

28

(1.0 kg manganese sulphate in 200 liters of water) 2-4 days before first irrigation to the crop and three

sprays thereafter, at weekly interval on sunny days. Do not apply manganese sulphate to soil as it is

not profitable. Durum wheat varieties viz. PDW-274, PDW-291 and PDW-233 etc. are more prone to

manganese deficiency; therefore these varieties should be avoided in deficient soils.

Zinc deficiency symptoms: The deficiency symptoms of zinc in wheat are observed at tillering

stage on second/third leaf from the top of plant. Zinc deficiency is manifested as light yellowish white

tissue between the mid-rib and margins in the middle or lower half of the affected leaf (Fig. 4).

Minute reddish brown spots are seen in the affected area. With the passage of time, these spots join

together and form reddish-brown lesions leading to the necrosis and drooping of the leaf.

Fig.4. Zinc deficiency symptoms in wheat

Amelioration: As soon as the deficiency symptoms appears on the wheat crop, top dress 25 kg zinc

sulphate heptahydrate (21% Zn) per acre. Under severe deficient situations, soil application may be

supplemented by foliar application of 0.5% solution of zinc sulphate. The solution can be prepared by

dissolving 1.0 kg zinc sulphate and 0.5 kg un-slaked lime in 200 liters of water. This solution is

sufficient for spraying an acre of wheat crop. Two-three such sprays at 15 days interval are needed.

Since rice is more susceptible to zinc deficiency, it is desirable to apply zinc sulphate

to rice in rice-wheat cropping system. Zinc sulphate applied to rice may suffice for the subsequent 3-4

crops owing to its residual effect and as such its repeat application may not be needed to every

crop/year provided the required dose has been applied. However, if zinc sulphate has not been applied

to rice and deficiency appears on wheat, the recommended dose of zinc sulphate should be applied.

29

Since by the time the deficiency symptoms of a micro nutrient deficiency appear on

the plant, the crop may have undergone considerable damage in respect of its ultimate yield. It is

therefore, desirable to test soils for their available micro nutrient status before sowing/transplanting a

crop in order to ensure timely corrective measures.

********

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Chapter 6

Balanced Nutrition for Sustainable Crop Production In India

Rajan Bhatt,Assistant professor (Soil Science)

KVK Kapurthala

  The rate of growth of agriculture in its broad coverage of crop production is much below the national growth rate. If the economy of country is to be improved through agriculture, it has to strengthen its programmes in such a manner to better utilize the natural resources along with balanced use of chemical fertilizers and other inputs. We are aware that for increasing the food production to fulfill the food requirements of the burgeoning population of the country sustainability of agriculture and environmental safety are the priority issues. To avoid wastage of precious national resource and to minimize the environmental damage there is need develop and demonstrate balanced use of chemical fertilizer. This will not only improve the crop production in sustainable way but also economize the crop production. Higher food production needs higher amount of plant nutrients. As no single source is capable of supplying the required amount of nutrients, integrated use of all sources is a must to supply balanced nutrition to plants.

What is balanced nutrition?

Balanced fertilization does not mean a certain definite proportion of nitrogen, phosphorus and potash or other nutrients to be added in the form of fertilizer, but it has to take into account the availability of nutrients already present in the soil, crop requirement and other factors. It should take into account the crop removal of nutrients, the economics of fertilizers and profitability, farmers ability to invest, agro-techniques, soil moisture regime, weed control, plant protection, seed rate, sowing time, soil salinity, alkalinity, physical environment, microbiological condition of the soil, available nutrient status of soil, cropping sequence, etc. It is not a state but a dynamic concept.

We can say that balanced use of fertilizers should be mainly aimed at :

(a) increasing crop yield, (b) increasing crop quality, (c) increasing farm income, (d) correction of inherent soil nutrient deficiencies, (e) maintaining or improving lasting soil fertility, (f) avoiding damage to the environment, and (g) restoring fertility and productivity of the land that has been degraded by wrong and exploitative activities in the past.

Balanced use of plant nutrients corrects nutrient deficiency, improves soil fertility, increases nutrient and water use efficiency, enhances crop yields and farmers income, betters crop and environmental quality. To reap the benefits of balanced use of plant nutrients, it is important to have good quality seed, adequate moisture and better agronomic practices with greater emphasis on timeliness and precision in farm operations.

Soil testing is one of the most important tools to practice balanced fertilization. Balanced fertilizer rates differ from area to area and also from crop to crop. Through soil testing farmers can know how much and what kind of fertilizer to use for each crop. A further refinement in fertilizer dose is possible on the basis of type of crop and its variety, water availability and its quality, availability of organic manures, crop residues, biofertilizers, etc. Since the initiation of green revolution in late

31

sixties, India has made a remarkable progress in fertilizer nutrient use with the introduction of high yielding varieties of wheat and rice. Crop production under intensified agriculture over the years has resulted in large scale removal of nutrients from the soil, resulting in negative balance and declining soil fertility. Organic sources are undoubtedly an important source of nutrients but their amounts and available nutrient content and the release rate is woefully inadequate for meeting the demands of intensive and high yielding crop production. India is presently using 15 mt of nutrients in the form of chemical fertilizers. Supplying the same through organic sources would require more than a thousand million tones, which is an impossible task indeed. Such organic manures in monumental volumes are neither available nor can be generated. Thus organic sources of nutrients can only be relied upon on meeting parts of the nutrients needs of the crop. They should be added along with chemical fertilizers for ensuring stability and sustainability of food production.

In India fertilizer consumption increased from less than 50,000 tonnes in 1950 to 15 million tones in 2000 and the food grain production increased from 50 mt to 200 mt in the same period, indicating a direct relationship between the fertilizer use and yield increase. The green revolution or spectacular increase in production would not have been possible without many fold increase in use of fertilizers. The high yielding varieties became a catalyst for the conversion of chemical energy into biological productivity. We have not yet realized the full potential of these varieties. Even the optimum potential of available technology remains mostly unrealized in most regions as nutrient input does not match the needs of the crop and soil. There are vast differences in consumption of fertilizers per ha of cropped area in different regions. The fertlizer consumption varies from 114, 103, 58, 47 kg (NPK) per ha cropped area in north, south, east and west respectively. Some states like Punjab are using more than 167 kg nutrients per ha as against some using less than 10 kg nutrients per ha. About 70 – 80 per cent fertilizer is used for growing rice and wheat. Besides these the major recipients of the remaining fertilizer use are sugarcane, cotton, potato, plantation and horticulture crops. The lowest fertilizer use is in rainfed farming, which covers nearly 66 per cent of the total cropped area in the country. It hardly needs to be stressed that in these rainfed areas more from deficiency than moisture inadequacy. But the later is more appreciated than the former.

There are also wide differences in the consumption ratio of three major nutrients N : P 2O5 : K2O in different regions, crops and cropping systems. These differences also got magnified and showed aberrations due to adhoc changes in pricing policy of fertilizers during the recent years. This and the NPK ratio for India changed from 5.9 : 2.4 : 1.0 in 1991-92 to 9.7 : 2.9 : 1.0 in 1993-94. There is also divergence in ratios in different regions. While the ratio in 1995-96 was 41.4 : 8.5 : 1.0 in northern states and 3.8 : 1.4 : 1.0 in southern states. Such divergence in new ratio is also due to the differences in the quality of land, inherent soil fertility, cropping systems and degree of exploitive agriculture.

Soil test summarizes indicate that 98 per cent Indian soils have low to medium available P and 60 per cent medium K status whereas, N continues to be universally deficient. 47 per cent soils are deficient in Zn, 12 per cent Cu and 4 per cent in Mn. In some states and crops the deficiency of B and Mo are also becoming limiting factors for crops production. In recent years a phenomenal increase in S deficiency has been witnessed specially under intensive cropping system where high analysis fertilizers devoid of S are used. The S deficiency is more pronounced in crops like oil seeds, legumes and intensively fertilized rice and wheat. Infact, the spectrum of S deficiency is increasing so rapidly that in future it will become on of the major yield limiting factors. It is said that the planners are more concerned with the yield barriers of some high yielding varieties but do not seem to be concerned with the rapidly changing scenario of plant nutrient deficiency and the pivotal role of fertilizers in food security. Thus in a situation where besides NPK the nutrients such as Zn, Fe, Mn,

32

Cu, B and S are also becoming limiting factors, It is unthinkable to have a sustained food security without balanced and integrated use of nutrients from external sources. The spectrum of nutrient deficiency is becoming more apparent under areas of intensive cropping systems which are the main contributors of National food stock of Food Corporation of India. There are signs of yield stagnation and low responses to fertilizers and other inputs because of imbalanced fertilizer use.

Nitrogen no doubt is the most limiting factor for Indian agriculture, but nitrogen alone is not enough and fertilizer does not mean nitrogen fertilizers only. Lack of this appreciation has led to poor results in most cases. Improving N use efficiency is the major problem for improving economy of its use especially in rice growing areas.

Green manuring with legumes and other means of biological nitrogen fixations such as through Blue Green Algae, Azolla, etc. can contribute to some of the N needs of rice crop but there are numerous technological, economic and operational problems to their use. At best they can be relied upon for 30 – 60 kg supply under good management. The efficiency of use of biofertilizers is more crop specific, location specific and management specific and unless there is a reliable system of quality control and a good system of storage, transportation and management in the field, the expected contribution will not be realized.

No doubt the awareness of balanced use of fertilizers is growing, but enormously wide N : P : K ratio are a matter of great concern. It is amazing that NPK ratios in Haryana during 1995-96 was 186 : 42 : 1 as against 64 : 14 : 1 in Punjab and 1.9 : 0.6 : 1 in Tamil Nadu as against 8.9 : 2.8 : 1 in whole of India. Bringing this ratio closer to the desirable ratio of 4 : 2 : 1 for cereals is essential for maximizing the efficiency of fertilizers. The matter is more urgent lest in the long run, disappointingly low yields result. The situation of P and K is more worrisome in India.

The declining use efficiency of fertilizers and of soil productivity are other matters of concern. This fatiguing effect is more prominent in frontier states of green revolution such as Punjab, Haryana, U.P. and other intensively cropped areas of the country. It has been estimated that annually we are robbing the soil of more nutrients in the form of biomass than returning to it in the form of fertilizer and manures. The annual negative balance seems to be of the order of about 10 mt of NPK. It will become manifold when we attempt doubling the productivity and production. If this nutrient drain continues, the sustained high productivity and sustainability of agriculture will be an impossible task.

India is adding every year population to one Australia and New Zealand and it is estimated that by 2025 the population of the country will touch 1.4 billion mark. For feeding such a large population, India may need about 300 million tones of foodgrains annually. It may require 35-45 mt of nutrients from both organic and inorganic sources of fertilizers. Besides these it will also need thousand tones of Zn, Fe, Mn, Cu and B.

It is not only the huge amounts of fertilizer nutrients which matters but also the use efficiency and management system which will determine their economics or benefit/ cost ratio is equally important. Thus, the key to future national food security and national security lies in balanced and integrated supply and management system, and there is no alternative to it. Balanced fertilizer use is also necessary to improve the economics or profitability of fertilizer use which provides incentive to farmer for its efficient use. It also improves the quality of the produce which is very much in demand for the export market as well as for home market. It hardly needs to be stressed that many wrong

33

notions about fertilizer use spoiling the soil quality are related to imbalanced and imprudent use of nitrogenous fertilizers only.

No single source of plant nutrient, whether it is chemical fertilizer or organic manure or green manure or biofertilizer or crop residue is in a position to meet the growing crop nutrient need. Moreover, the right kind of nutrients required by the crop crops may not be achieved from a single source. For example different chemical fertilizers can supply the nutrients like N, P, K, Zn and S; Green manuring use can meet a part of nitrogen requirement, one tone organic manure can add about 12 kg NPK and also some micronutrients; crop residue like rice straw is a good source of potassium and use of bio-fertilizers can supply nitrogen @ 20-25 kg/ha and mobilize soil phosphorus. This implies that integrated use of plant nutrients is essential mainly for two obvious reasons (i) to increase nutrient supply and (ii) practice balanced fertilization. In addition integrated use of different sources of plant nutrient helps to increase their efficiencies and also crop productivity.

All out efforts should be made to educate farmers to practice balanced use of fertilizers. Of late, some fertilizer companies and associations have come forward to educate the villagers, publication of literature in regional languages related to balanced use of fertilizers for higher crop yields in a sustainable way. The actual time has come, the farmers, researchers and other related communities should come forward and act in this respect. The chemical fertilizers should be used judiciously and use manures along with chemical fertilizers for improving the crop yield and soil productivity in a sustainable way. Many more activities are being planned to promote the balanced use of fertilizers. And it is hoped that all these efforts would lead to desired awareness and as a result balanced fertilizer use would become a reality in near future.

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Chapter 7

Green Manuring in relation to the soil fertility and soil health

Rajan BhattAssistant professor (SS),

Krishi Vighyan Kandra, Kapurthala

IntroductionOwing to the constant production of crops from the soil, the latter is being depleted gradually of its nitrogenous and other nutrients. An ordinary crop takes about 25 lb of nitrogen from an acre. It is, therefore, necessary to replenish the soil with the elements, which are removed by the crops year after year.

 Organic matter is the life of the soil because it contains all the essential elements required for plant growth. It also serves as food for soil bacteria. Decomposed organic matter, known as humus, improves the soil tilth and helps the plant to grow. Well-stored farmyard manure is most important of all organic manures, but it is not available in sufficient quantity. Farmyard manure, if not properly stored, loses its nutrient-supplying value to a great extent.

 Therefore, in order to conserve farmyard manure and town refuse properly, two schemes were taken in hand by the Agricultural Department during the Second Five Year Plan (1956-61). But the answer to this problem is green manuring in which no such losses are there.

Green Manuring

Farmyard manure and compost are not available in sufficient quantities to the farmers to meet their full requirements. Artificial fertilizers are also in short supply. Owing to the intensely hot summers, the available humus in the soil is burnt up quickly. A periodical application of organic matter is, therefore, essential to replenish the loss of humus, which is necessary for keeping the soil in good condition by enhancing the supply of nitrogen and by promoting the growth of microorganisms. A leguminous crop producing 8 to 25 tonnes of green matter per hectare will add about 60 to 90 kg of nitrogen when ploughed under. This amount would equal an application of three to ten tonnes of farmyard manure on the basis of organic matter and it’s nitrogen contribution. The green manure crops also exercise a protective action against erosion and leaching of the various nutrients into the deep soil layers.

Green-manuring is, thus, a very useful soil-improving practice for building up soil fertility. First, it increases the soil fertility by the direct addition of nitrogen to the soil. Second, it improves the soil texture by the addition of humus or organic matter, which is essential for making the soil more productive. The addition of organic matter improves both heavy and sandy soils, as it has a binding effect on the loose particles of the sandy soils and makes the hard and heavy soils porous. Thus, it also increases the water-holding capacity of the soil. Besides, the conditions for increasing the number of useful bacteria in the soil are also improved.

Kind of green manuringThe practice of green manuring is performed in different ways according to suitable soil and climatic conditions of a particular area. Broadly the practice of green manuring in India can be divided into two types

35

1. Green manuring in situ: In this system, green manure crops are grown and buried in the same field, which is to be green manured, either as pure crop or an intercrop withy the main crop. The former system is followed in the northern India while latter is common in the central and eastern India.

2. Green leaf manuring: Green leaf manuring refers to turning into the soil green leaves and tender green twigs collected from shrubs and trees grown on bunds, wastelands and nearby forest areas. This system is generally followed in the central India.

The crop generally used for green manuring is dhaincha (Sesbania aculeata) though the cultivation of sun-hemp and guara is also in vogue. The crops commonly used for green manuring in our country are the following:

Sunnhemp (crotolaraia juncea), Dhaincha (Sesbania aculeate), senji (Melilotus parviflora), Cowpea (Vigna catjang), berseem (Trifolium alexandrinum) etc. Sunhemp is the most outstanding green manure crop and is well suited in almost all parts of the country and fits in well with the sugarcane, potato, garden crops and the second season paddy in southern India and with irrigated wheat in the north. Dhaincha is also an outstanding green manure crop. It does well in the waterlogged and alkaline soil for it’s reclamation programme. Green-manuring is in common use in irrigated lands, lands, but its popularity in barani land is hindered by the lack of irrigational facilities.

The Extension of Green-Manuring Scheme came into operation in the Punjab with effect from April 1, 1961. It aims at popularizing the use of green manure in the State. The Government encourages the adoption of this practice by the farmers by granting subsidies on seeds of green-manuring crops. The Irrigation Department also grants remission of water-rate, if crops are buried for green-manuring before 15th of September.

The total area under the green-manuring crops in the district, during the past few years, has been as under:

Table: 1 Area under green manuring crops with time.

Year Area under green-manuring crops (ha)

1955-56 716

1960-61 7785

1965-66 13254

1967-68 26096

(Source: Town Compost-cum-Field Manure Officer, Punjab, Chandigarh)

Techniques of green manuring in the field:

The maximum benefit from the green manure crop cannot be obtained without knowing the

When it should be grown. When it should be buried into the soil. How much time should be given between the burying of the green manure crop and the

sowing of the next crop.

Time of sowing of the green manure crop

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Normally the green manure crop should be grown immediately after the monsoon rains. As far as cultivation practice involved, no special care is needed in the preparation of the seedbed. Soil must have sufficient moisture for the quick germination and rapid early growth. Phosphatic fertilizers, if applied, should be evenly broadcast. Usually the seed of the green manure crop is broadcast preferably with higher seed rate.

Stage of burying of the green manure crop:

From the results of the several experiments, it is observed that best results of the green manuring are obtained if it is buried at the flowering stage. Majority of the crops take about 6 to 8 weeks to reach at the flowering stage from sowing

4 6 8 100

5

10

15

20

25

Effect of age of sunnhemp on the succeding wheat

S...

Age of buring of sunnhemp crop (Weeks)

Wh

eat

yiel

d p

er a

cre

Stage at which sun hemp was buried made a significant effect on the wheat yield. However basic principle is in green manuring crops, should aim at maximum succulent green matter at buring.

Time interval between burial of green manure crop and the sowing of the next crop: The time interval should be allowed for complete decomposition of the turned in green manure crop before planning of the next crop and that time should depend upon the following factors:

1. Weather conditions2. Nature of the buried green material

In areas receiving rainfall >50 inches humid conditions favors decomposition. If the green manure crop is succulent, then there is no harm in transplanting the paddy immediately after turning in the green manure crop. However, in case of the woody, then sufficient time should be allowed for it’s proper decomposition before planting the paddy. e.g. when succulent green manure crop of around 8 weeks was buried then paddy can be planted without having any adverse effect on the yield. But when dhaincha become woody ( 12 weeks), it was necessary to bury it about 4 to 8 weeks first for it’s decomposition before planting paddy. In areas receiving 25 to 50 inches rainfall, green manure crop required about 6 to 8 weeks to decompose. It is only because of lesser moisture conditions.

When green manure crop was intercropped in between the rows of the main crops like paddy, cotton, sugarcane etc. then it is buried in the succulent stage for it’s rapid decomposition.

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Plants suitable for green manuring in the field or In situ

An ideal green manure crop should possess the following desired characteristics, as listed by

Dr. R. R. Agarwal (1965) are as follows

1. It should be a legume with good nodular growth habit indicative of rapid nitrogen fixation under even unfavorable soil conditions.

2. It should have little water requirements for it’s own growth and should be capable of making a good stand on poor and exhausted soils.

3. It should have a deep root system, which can be open the sub-soil and tap lower regions for plant nutrients.

4. The plant should be of a leafy habit capable of producing heavy tender growth early in its life cycle.

5. It should contain large quantities of non-fibrous tissues of rapid decomposability containing fair percent of moisture and nitrogen.

Advantages of the Green manuring

Following are the some of the advantages of the green manuring

1. It add organic matter to the soil. This stimulates the activity of the soil microorganisms.2. The green manuring crops return to the upper soil plant nutrients taken up by the crop from

deeper layers.3. It improves the structure of the soil.4. It facilitates the penetration of the rain water into the surface of the soil, thus decreasing the

runoff and thus erosion.5. The green manuring crops hold plant nutrients that would otherwise be lost by leaching.6. When leguminous plants, like sun hemp and dhaincha are used as green manure crops, they

add nitrogen to the soil for the succeeding crop.7. It increases the availability of certain plant nutrients like phosphorus (P2O5), calcium,

potassium, magnesium and iron.

Disadvantages of the green manuring

Every coin has got a head and a tail and it is the case with the green manuring. Some disadvantages are also associated with green manuring. When the proper technique of green manuring is not followed or when weather conditions become unfavorable, the following disadvantages are likely to become evident/happen.

1. Under rainfed conditions, it is feared that proper decomposition of the green manure crop and satisfactory germination of the succeeding crop may not take place if sufficient rainfall is not received after burying the green manure crop. This particularly applies to the wheat regions of the India.

38

2. Since green manuring for rabi season (Wheat) means the loss for the kharif crop, the practice of green manuring may not be always economical. This applies to the regions where irrigation facilities are available for raising kharif crop along with easy availability of fertilizers.

3. In case the main advantage of the green manuring is to be derived from addition of nitrogen, however sometimes the cost of growing green manure crops may be more than the cost of commercial nitrogen fertilizers.

4. An increase of diseases, insects and nematodes is possible.5. A risk is involved in obtaining a satisfactory stand and growth of the green manure crops, if

sufficient rainfall is not available.

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Chapter 8

Laser Leveller for precision land levelling for judicious use of water in Punjab

1. An Overlook to the Water scenario in the Punjab:

Water has been prioritized to be the most crucial resource. Agriculture uses almost 85% of the total water available in the country. Shrinking water resources owing to over exploitation of ground water in Punjab threatens the maintenance of agricultural productivity. As a result, the water table is falling in 90% area of the state. With the inception of Green revolution in the Sixties, the water table started declining and the area having water table below 30 feet depth has increased from 3% in 1973 to 90% in 2004. During 1993-2003, the average fall of water table in the Central Punjab was 50cm per annum. However, in some of the areas, the fall of water table is even more than 80- 100 cm per annum. Out of 141 blocks of the state more that 100 blocks are over exploited. It is projected that by 2023 in Central Punjab, the water table depth will be below 70 feet in 66% area, below 100 feet in 34% area and below 130 feet in 7% area. Correspondingly in each district, the percent area below 70 feet depth will be 100% in Moga & Sangrur, 80 % in Patiala, 70 % in Ludhiana, 60% in Kapurthala & Jalandhar. To arrest this dangerous trend of ground water exploitation, there is an urgent need to conserve irrigation water through various on-farm water conservation practices. Land Leveling through Laser Leveler is one such proven technology that is highly useful in conservation of irrigation water.

2. Need of the Laser levelling:

Unevenness of the soil surface has a major impact crop productivity through nutrient water interaction and salt and soil moisture distribution pattern. Land levelling is a precursor to good agronomic, soil and crop management practices. Farmers recognize this and therefore devote considerable attention in levelling their fields properly. However, traditional methods of levelling land are not only more cumbersome and time consuming but more expensive as well.

Fields that are not level have uneven crop stands, increased weed burdens and uneven maturing of crops. All these factors tend to contribute to reduced yield and grain quality which reduce the potential income of the farmer.

Effective land levelling is meant to optimise water-use efficiency, improve crop establishment, reduce the irrigation time and effort required to manage crop. It is a common knowledge that most of the farmers apply irrigation water until all the parcels are fully wetted and covered with a thin sheet of water. Studies have indicated that a significant (20-25%)

40

amount of irrigation water is lost during its application at the farm due to poor farm designing and unevenness of the fields. This problem is more pronounced in the case of rice fields. Unevenness of fields leads to inefficient use of irrigation water and also delays tillage and crop establishment options.

Laser Land Leveling seeks to explain the benefits of land leveling in fields, particularly rice fields, and help develop skills of farmers and operators in using laser technology to achieve a level field surface for the uniform distribution of the irrigation water.

It is also intended to enable the users to identify and understand the working of the various components of a laser-controlled land leveling system; undertake a topographic survey using a laser system; set up and use a laser-controlled leveling system and troubleshoot a laser-controlled levelling system

3. History:

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First of all, in Punjab laser leveller introduced on an experimental basis in the Sukhanand village of the Moga district on an area of 150 acres and around 300 farmers included in

Guiding the farmers regarding the setting of tripod and laser receiver mounted on laser leveller.

these demonstrations. It is reported that around 25 – 30% of irrigation water can be saved through this technique without having any adverse affect on the grain yield. Further even surfaced land helps in equal distribution of the pesticides, fertilisers, thus reduces these inputs too. Upto 400 units if electricity units can also be saved in one acre where the land is laser levelled.

Years Number of laser levellers in the Punjab2005 12006 82007 1502008 10002009 20002010 2585

Why Laser-level Land?Benefits of Laser Leveling

1. Reduction in time and water required to irrigate the field 2. More uniform distribution of water in the field3. More uniform moisture environment for crops4. More level and smooth soil surface 5. Reduction in seeds, fertilizer, chemicals and fuel used in cultural operations

Improved field trafficability 6. More uniform germination and growth of crops

The limitations include the following:

1. High cost of the equipment.2. Technical knowhow regarding the different parts which required the trained drivers

and staff.3.

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YieldResearch conducted by PAU has shown a large increase in rice yield due to proper field

leveling. The following table is self-explanatory:

Year Rice Yield(t h/a)

  Leveled Fields Unleveled Fields

1996

1997

1998

1999

Average

3.40

2.27

2.72

2.34

2.72

2.67

1.46

2.36

2.00

2.19

Source: PAU, Ldh

Study entitled “Comparison of levelled V/s unlevelled field plot in growing Paddy crop” carried out Krishi Vigyan Kendra, Kapurthala during the year 2007 shown the following resultsTreatments

T1 Laser levelled plot.T2 Control (levelled by farmer with ordinary leveller)

MethodologyLevelled land is a pre requisite for getting the optimum yield in paddy due to the fact

that Paddy requires sub merged conditions for the first 15 days to get it established after transplanting. Mostly some nursery seedlings die either lack or excess of water in the field. Thus, precision land leveling is a must for getting proper yield. Moreover, it takes more time to irrigate the field if it is unlevelled. Keeping this point in view, an on farm trial was conducted in which, 0.4 ha area was laser levelled and other 0.4 ha.area was ordinary levelled.

Soil Type : Loamy sand

Results:

Treatment

Variety Date of sowing

Date of harvesting

Tillers/hill 1000 grain wt.

Yield (q/ha)

Time to irrigate the plot (hours/ha)

T1 PAU- 08.06.07 24.10.07 7.7 2.59 70.3 11.25

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201

T2 PAU-201

08.06.07 24.10.07 6.9 2.54 69.8 16.25

Discussion:From the data it was evident that it took 11.25 hrs. to irrigate one ha. area if plot is

laser levelled in comparison to 16.25 hrs. required to irrigate ordinary levelled plot. Similarly there was considerable saving in the quantity of water used for irrigation purpose in laser leveled plot than the ordinary leveled. However, there was no significant difference obtained in the yield of Paddy between two treatments.

Organising farmer’s meetings on Laser leveller in the village Blairkhanpur of district Kapurthala

Weed ControlLand levelling increases yield by decreasing the weed population. Improved water coverage from better land levelling reduces weeds by up to 40%. This reduction in weeds results in less time for crop weeding. It also reduces the overall cost of cultivation by reducing the manpower assumed to be spent on manual weeding. A reduction from 15 to 6 labour-days per hectare is achieved.

How Laser Leveller Works

The working of laser leveller depends on the efficiency of accuracy of it’s parts. Any problem in the working of any part will affect the working of the Laser leveller. The laser-controlled system requires a laser transmitter, a laser receiver, an electrical control panel and hydraulic control valve.

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 Scrapper

 

 

The laser transmitter fitted on the tripod which itself is placed outside the field which is to be levelled.The laser transmitter transmits a laser beam, which is intercepted by the laser receiver mounted on the leveling bucket. The control panel mounted on the tractor interprets the signal from the receiver and opens or closes with a laser-controlled bucket. The use of laser-controlled equipment results in a much more level field – up to 50% better than leveling using other techniques. Laser leveling systems are commonly used in agricultural applications in Australia, Japan , the United States and it becomes popular in developing countries viz India, Pakistan etc.

How to Laser-level Land

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Laser levelling requires soil to be shifted from the higher points of the field to the lower points in the most cost-effective way so as to get the levelled surface. In most situations, fields will need to be plowed and a topographic survey undertaken before levelling starts.

Step 1. Plowing the Field

Plow the field preferably from the center of the field to the outwards. It is preferable to plow the field when the soil is moist because if the soil is plowed dry a significant increase in tractor power is required and large clod sizes may result. If the soil is very dry a one-way disc may be required. Disc harrows are ideal for second workings. All surface residues need to be cut up or removed to aid soil flow from the bucket otherwise crop residues will creat hinderence in the proper working of the laser leveller. In Punjab, It costs around Rs 500 per hour and it required around 2-3 hours to level one acre. Earlier ploughing decreased the time

Step 2: Conducting a Topographic Survey

After plowing the field,one must go for a topographic survey to record the higher and lower spots in the field. This we did after fitting the receiver on the extension rod and moving in whole of the field in a specific patteren. From the surveyed readings we can then establish the mean height of the field by taking the sum of all the readings and dividing by the number of readings taken. Lasers are now widely used to accomplish a topographic survey. They are very accurate, simple to use and readily available in most countries. Recordings can be taken up to a radius of 300 meters from the transmitter. One person can operate a laser leveller and one transmitter can operate 3-4 laser leveller at a time. The laser surveying system is made up of a laser transmitter, a tripod, a measuring rod and a small laser receiver. A major advantage of laser surveying is it’s accuracy, simplicity of use and only one person is needed. .Using a Laser Level

1. Open the tripod legs and adjust the individual positioning of the legs until the base plate is relatively level. Use the horizon as a visual guide to get the base plate level.2. Attach the laser transmitter to the base plate. 3. If the laser is not self-levelling, adjust the individual screws on the base of the transmitter to get the bubble into the centre of both circles. Most lasers will not rotate unless the transmitter is level.4. Once the transmitter is level attach the receiver to the staff and activate the sound monitor.5. The laser is now ready to commence recording heights.

Record all the readings very carefully in your notebook so that average point can be find out very accurately so that the desired results can be obtained after levelling.

Step 3: Levelling the Field

Levelling a field involves the following steps:

1. The laser-controlled bucket should be positioned at a point that represents the mean height of the field. 2. The cutting blade should be set slightly above ground level. 3. The tractor should be driven in a circular direction from the high areas to the lower areas in the field.

46

Discussing the performance of four wheeler laser leveller in the field

4. To maximize working efficiency, as soon as the bucket is near filled with soil the operatorshould turn and drive towards the lower area. Similarly as soon as the bucket is near empty the tractor should be turned and driven back to the higher areas so that levelled surface can be obtained..

5. When the whole field has been covered in this circular manner, the tractor and bucketshould then do a final levelling pass in long runs from the high end of the field to the lower end.

Troubleshooting: Sometimes there are some problems in the working of some parts there are the desired solutions as per the trouble.Problem Cause/SolutionA.Bucket will only move in one direction

Check hydraulic connections Check for contamination in oil lines Check electric connections on solenoid Check pressure relief valve setting on control valve

B. Bucket will not raise or lower Check the transmitter is working Check pressure relief valve setting on control valve Check hydraulic connections Check electric connections on solenoid Check for contamination in oil lines

C. Bucket doesn’t respond in certain parts Line of vision between transmitter and receiver blocked of field Receiver the same height as tractor cabin

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Laser beam above or below the receiver height

On-farm discussion with the farmers regarding the performance of four wheller laser leveller

Bucket shudders when first started

1. Check pressure relief valve setting2. Oil cold or no load in bucket

Other Equipment

Other equipment may be needed when using a laser system for topographic surveying. ThisIncludes:

1. Tape: One 100-meter tape.

2. Compass: If direction and bearings are to be recorded a compass will be required.The compass can be used to set magnetic north on the level and allow recordings tobe taken from it

3. Book: A notebook is required to record all measurements while the field survey prior to laser levelling.

4. Pencil/Eraser: A pencil and eraser are preferable to an ink pen in thefield.

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Chapter 9

Water resource management for sustainable crop production in India

Rajan Bhatt

Department of Soils,

Punjab Agricultural University, Ludhiana-141 004

The life of mankind and almost all the flora and fauna on the earth depends on the availability of fresh water resources. Water is used by every one every day. The three major users of the water are domestic water supply, industry including power generation and agriculture. About 2/3 rd of water withdrawn world wide from rivers and ground water is used for irrigated agriculture. It is a renewable natural resource but total volume in hydrological cycle in the globe is constant and very small. Of the earth’s total water volume of about 1400 Mkm3, about 97% is saline ocean water that is unsuitable for human as well as for plant use. About 30 Mkm3 of remaining fresh water exists in the ice caps and glaciers and 4-6 Mkm3 of the ground water remains essentially inaccessible. Thus only the resources consisting of one percent of the earth’s water is cycled in the hydrological cycle. Nations of the world particularly the developing countries have made huge investments for developing their water resources to increase their agricultural production. But there is an upper limit to the availability of water resources in each country.

We have entered the third millennium in the history of man kind. The population of the world which was 2.5 billon 50 years ago has become 6 billons and is likely to cross the 8 billon mark in the next quarter of the century. In India, it has almost crossed 1 billon mark and is expected to reach 1.4 billion in the next 25 years. Because of the increasing population and consequently the requirement for food grain and other agricultural commodities, it is feared that in future water may become the major limiting factor for producing enough food, fiber and fuel for the projected population.

The sources of all water is precipitation and we are concerned with that part of it which falls on the surface of the earth and becomes useable. Water reaching the earth’s ssurface partially infiltrates into it and partly moves as surface runoff. The infiltrated water is partly retained in the upper surface of the earth constituting the rot zone of the vegetation and partly lost as deep seepage which adds to the ground water. Soil stored water is lost through direct evaporation or evapo-transpiration. Efficient management of water envisages that the maximum portion of water be used by vegetation and minimum lost as runoff and deep seepage.

As water is becoming scarce, it is becoming increasingly important to conserve the available water. A number off-farm and on-farm measures need to be imposed to use the water more efficiently. As water cannot be stretched further for agriculture, it is faced with challenges to use water more beneficially and efficiently. Questions are being asked whether the available water resources will be

49

able to sustain the future population. Can we achieve the sustainable use of water through improved management?

Need for sustainability:

India has achieved spectacular increase in the agricultural production during the past few decades from . The success of the green revolution is largely attributed to the expansion of irrigation net work, that existed in the country. Canals in the initial stages and tube wells immediately thereafter have played a crucial role in the quantum jump in production. This development of irrigation has been a mixed blessing. While it has helped increase production, It has caused water logging and salinization in many areas. Similarly over-exploitation of ground water has resulted in declining water levels in some area. Soil erosion and siltation in reservoirs and flood damage are the result of the management of rain water. All these effects are threatening the sustainability of the system and call for special efforts to achieve sustainable use of water.

According to food and agricultural organization (Pereira et al, 1996). Sustainable development is the management and conservation of natural resource base and the technological change to ensure the attainment and continued satisfaction of the human needs for present and future generations. Such sustainable development including Agriculture, forestry and fisheries conserves genetic resources and is environmentally non-degrading, technically appropriate, economically viable and socially acceptable.

Therefore the objectives of sustainability in the present context is to use water resources to achieve increased production to meet the needs of ever increasing population and aspiration of the people without compromising the productivity of land and water.

Major problems and issues related to sustainable water development:

Agricultural production can only be sustained on a large scale basis, if the land, water and forests on which it is based are not degraded. Many interrelated issues and problems can be identified in this regard:

Inefficient use of water at farm level. Depletion of ground water. Salinity and water logging Erosion and sediment ion Deforestation Inadequate control of agro chemicals Improper attention to health considerations.

The problem and issue differ from country to country and often from one project another project within the same country. The most wide spread and perhaps most serious environment problem that contributes to unsustainable water resources development in agriculture is caused by water logging, salinization and sodification. It is reported that out of 270 m ha of presently irrigated area worldwide, 60-80 m ha are affected to some extent by water logging ,salinity and 20- 30 m ha are severely affected (UNEP, 1989).Improving irrigation efficiency will not only reduce the hazards of water logging and salinization , but also provide additional water for irrigating more land.

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Deforestation, erosion and sedimentation problems are often related to the water development projects. FAO (1989) reported that current rate of deforestation unsustainable. Deforestation can cause soil erosion rates10 to 100 times greater than the natural levels. Ground water management is causing serious concern in many arid and semi arid countries. The rate of pumping withdrawal exceeds the rate of recharge of aquifer resulting in decline of the ground water level. Irrigated agriculture with its associated intensive cultural practices, such as high levels of fertilizers and agrochemicals use and deep percolation of water contributes to water pollution .Nitrate contamination of ground water is likely to be of importance where rural water supplies are concerned.

Requisite of sustainable resource management

Before initiating steps for sustainable management of a resource, it is essential to know the availability of the resources. Availability of water resources is not static. It varies in the time and space. The water interacts with the soil in as much as it is first stored in the soil and then utilized by the plants. Only that part of it is used as evapo-transportation (ET) which is retained in the root zone. The management of water for sustainable use would require

1. A fair assessment of the availability of the resources, its distribution in time and space together with land characters with which it interacts.

2. Conservation of the resources to increase its availability for the useful purposes.

3. Efficient manage for optimizing returns from the source and avoid any adverse effect on environment in general and quality of the resources in particular.

Assessment of water resources

Precipitation is the main sources of the water resources. It is partitioned into surface runoff, deep seepage and soil water. The runoff stored in reservoirs and transported through canal net work comprises the surface water resources. The seepage water joining the groundwater table becomes the ground water resource. The water retained in the soil is used by vegetation and is called effective rainfall.

Currently water resources are reported as potential surface and developed surface water and potential and developed ground water. While the surface water can be measured as flow or surface storage, the ground water is usually estimated from fluctuations of the ground water level and specific yield from aquifers Only limited data for specific yield is available. Similarly precise data on water table fluctuations and also not available. Information on available water resources in India is collected and reported by Ministry of Water Resources. The country receives on annual average rainfall of 1200 mm which when multiplied by the geographical area works out to be 400 M ha m. It is estimated that 188 M ha m of this water constitutes runoff. Because of the nature of terrain and distribution of

51

rainfall, it is estimated that 69 M ha m runoff can be harnessed for irrigation. One hundred and seventy five M ha m water enters the soil of which 130 M ha m is retained in the soil and 45 M ha m is estimated to be added to the ground water every year. The water retention in the soil is available for the use of vegetation. It must be conserved against loss by direct evaporation and use by unwanted vegetation. Unfortunately this has not received adequate attention of planners.

Irrigation potential development and utilization

The ultimate irrigation potential of the country has been estimated to be 113.2 M ha. It comprises 58.3 M ha from major and medium irrigation schemes; 15.3 M ha from surface minor irrigation schemes and 39.6 M ha from ground water development.

Out of an average surface runoff flow of 188 M ha m, a live storage of 16.55 M ha m has been developed so far. Dams to create additional live storage of 7.67 M ha m are under construction. and 13.10 M ha m are under consideration. Thus it appears that total live storage capacity as per the present programmed will be around 37 M ha m while the utilizable surface water is estimated as 69 M ha m. The total replenishable ground water resources are 45.3 M ha m. Assuming 6.83 M ha m required for drinking, industrial and other uses, the ground water resumes and irrigation are 38.5 M ha m. The net draft so far is estimated as 11.57 M ha m which is about 30 percent of the potential available for irrigation. However ground water development varies from states to states. For example, ground water development in Punjab stands at 98.2% while in Orrisa it is about 7.13% only.

Management of water resources

Water is the most precious commodity and its rational development, conservation, distribution, use and management need special consideration for improving productivity of land, better efficiency and economic return, and preserving the ecological balance. Some important management issues for better available water resources are:

1. Exploitation of water resources2. Crop planning in relation to water availability3. Increasing water use efficiency.4. Safe use of saline/sodic ground water for agriculture.

Exploitation of water resources:

During the post independence era, much efforts has been made by the state and central government to harness the maximum amount of potential water resources in the country.

However, due to a number of factors, including high cost, the gap in potential, planed and realized water resources have been increasing. Various commissions and committees have indicated the need for reducing this gap through command area development approach for optimizing benefits from the investments made in the irrigation projects.

There is strong evidence indicating higher productivity and efficiency of ground water. However, ground water is liable to over exploitation thereby failing to sustain the long term growth process and also creating inequity as resource poor farmers will be at a disadvantage. Ground water resource development should receive the highest priority in our water resource development planning but to avoid over exploitation and to ensure equitable distribution of water on a watershed basis, a legal framework should be provided.

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Crop planning in relation to water availability

The command area water management includes crop planning on the basis of availability of water at different times of the season. In practice, crop plans are prepared by the farmers themselves on the basis of their preference for certain crops, social and economic considerations and availability of water. Since the issue involved in crop planning are complex, the cropping pattern for the year should be fixed by the project authorities in consultation with the agricultural university, credit agencies, irrigation engineers, organization dealing with supply of inputs, and farmers representatives. The evaluation of cropping pattern should be a gradual process of adjustment of the factors responsible for deciding the cropping plan in a command area.

Canal irrigation in India was mostly designed for stabilizing agriculture and for extensive rather intensive/productive agriculture. Our major and medium irrigation project can hardly meet the needs of the changing scenario of high yielding varieties and new cropping systems that are more exacting and demand time supply of irrigation water at critical stages of the growth. In the wheat belt of Punjab and

Haryana, the dwarf high yielding varieties of wheat requires irrigation at crown root initiation stage or in the first three weeks after sowing, whereas the previously grown tall varieties could withstand water stress in the first two months after sowing. The introduction of the new varieties necessitated changes in the irrigation at the most critical stages of crop growth. Thanks to water management research over the last 2 to 3 decades, specific information has been available for increasing the efficiency of water use as enhancing returns to the irrigation. Of late, irrigation schedule can be calculated with computer model based on formation on climate, soil, crop and management factors.

Increasing water use efficiency

The ultimate aim in the area of water management is to use water more efficiently by keeping productivity at a high level. Water-use efficiency being a ratio is influenced by changes in both the numerator (dry matter production) and denominator (evaporation). Water use efficiency can be increased by genetic and environment manipulations of the crop. It can also be increased by decreasing the evapotraspiration and other losses of water. Crop yields can be increased without significant increase in water used by selecting suitable crop varieties adopted to climatic conditions of the locality and through agronomic management, such as using good quality seed, sowing at appropriate time and depth, placing balanced fertilizers in the soil in adequate quantity and at right time, as well as protecting crops from infestation from weeds, insect pest and diseases. The use of anti-transpirants, growth retardants, mulches, shelterbelts, etc. have been reported to increase the water use efficiency to various extant through reduction in evapotranspiration losses.

Increasing irrigation efficiency and improving drainage

Irrigation water is subject to three kind of loses, viz, conveyance, application and distribution/deep percolation. In the chain of delivery system it has been proved that as much as 70% of water is lost in these three kinds of ways. No doubt some of the progressive states have taken up the work of lining the canals and distributaries but lining of field channels with good quality material is equally important.

53

Experimental evidence is available that deep percolation losses of water which ranges from 60-70%, or even more in case of rice, can be reduced considerably with a change in the concept of keeping standing water to scheduling irrigation at the point of disappearance of tillage operation. It has been proved beyond doubt that furrow irrigation in wide-spread crops is the best, followed by border method of irrigation whereas check basin irrigation has proved to be the best most efficient method of irrigation in term of water economy. However, a lot of extension effort is required to educate the farmers to adopt the right method and schedule of irrigation in relation to type of crop sown, volume of discharge, and soil type. In water deficit areas adaptation of efficient irrigation methods like drip irrigation

Thus, it is a greater emphasis fact that the most important fact that the importance of the water is of great thus to conserve the conserve that the conservation opf the water is of grtaet importance .water is of

Chapter 10

IMPROVING THE SOIL HEALTH

54

Rajan BhattAssistant Professor (Soil Science)

Krishi Vigyan Kendra, Kapurthala

Soil is an exhaustible storehouse of plant nutrients. With the introduction of high yielding,

fertilizer responsive varieties and increase of the irrigation facilities during the green revolution era,

undesirable mining of the soils for plant nutrients has resulted in degradation of soil health. During

the mid-sixties, high yield could only be obtained by the application of nitrogenous fertilizers. Soon

the soils were depleted of available phosphorus and phosphoric fertilizers had to be applied, along

with nitrogenous fertilizers to sustain high yields. So, this over exploitation of soils with multiple

cropping and use of high doses of fertilizers and other Agro-chemicals with high rates of chemical

purity have resulted in deficiencies of macro, secondary & micro nutrients. It was estimated that the

prevalent rice wheat cropping system removes NPK as high as 600-700 kg/ha/annum. Inadequate

supply of these nutrients can lead to a serious decline in yield of these crops. With the present pace of

development, the land resources are shrinking fast & their quality deteriorating, and there is a little

scope for expansion of the area under these crops. Thus, the only option open to us today is to take

care of our soil health, protect it from degenerating or negative factors.

In Punjab, mechanical harvesting of wheat and rice is a common practice, which has created

problem of residue management. Practice of making bhusa from wheat residue left over in the field is

being practiced on very small scale also. Paddy straw left over is shredded and burnt after drying in

the field. This practice of burning paddy and wheat straw has further aggravates the problem of soil

degradation in terms of death of helpful soil fauna/flora and loss of nutrients. Such crop residues, if

managed properly, have great potential to be utilized as source of plant nutrients in achieving

sustainable crop productivity and for substituting a part of fertilizer requirement of the field crops. On

the other hand, the use of animal excreta as nutrient source is also restricted because of its competitive

demand as fuel for cooking. Until alternate energy sources are made available in the rural areas, there

is little likelihood of the large scale use of cattle dung as a source of plant nutrients. The scope for

55

practicing incorporation of green manure is also limited due to the constraints of time, water, seed &

labour etc.

Keeping all the above soil health constraints in mind, different interventions, involving

balanced use of nutrients coupled with organic manure i.e. FYM, green manure and recycling of crop

residues were conducted under the Technology Assessment and Refinement Project in Jalandhar and

Kapurthala Districts to explore the possibility of replenishment of degraded soil. All these

interventions were based on the assumption, that neither the chemical fertilizers, nor the organic

sources exclusively can achieve the production sustainability of soils as well as crops under highly

intensive cropping systems. Under such situations complementary use of available sources of plant

nutrients (organic/biological) along with mineral fertilizers is vital significance for maintenance of

soil productivity.

Chapter 11

56

Increasing production in waste land and degraded fallow lands: Need of hour

Rajan BhattDepartment of Soils

Punjab Agricultural University, Ludhiana

“Everything else can wait but not agriculture” said Pandit Jawahar Lal Nehru our first Prime

minister immediately after independence in 1947. This holds good for the development of our

nation where each year 16 million people add to our population. Now, this increasing

population occupies the agricultural land day by day, however at the same time total grain

demand also goes on increasing. Further, due to pressure from man, livestock and through

short sighted development policies vast tract of land have progressively lost their ecological

and fertility values. Land being the most important but limiting resource can not be afforded

to keep Therefore with these newly emerging challenges, main attention is paid towards the

waste land to fulfill the needs of the increasing population. It has become necessary to make

the best possible use of our waste lands and fallow land through scientific land and water

management to produce food, fodder, fuel and fruits. Hence, proper land use plays a vital role

in the total planning for the development of the nation.

Waste land and fallow land

Simply defining waste land are those which for one or other do not fulfill their life

sustaining potential (National wasteland development board 1985). Further waste land can

also be defined as any land which is not producing green biomass consistent with the status of

soil and water or it can be the land which is presently lying unused or which is not being used

to it’s optimum potential due to some constraints (National Remote Sensing Agency 1985).

Deforestation of the land for meeting the demand of firewood, ill managed grazing, floods,

drought and many other ecological and soil inherent factors. Waste lands are basically are of

57

two type culturable and unculturable waste lands. Culturable waste lands the potential for

development of vegetative cover but those not being used currently for various reasons.

Unculturable waste lands are those which are not capable for development of vegetation

cover and is being used to different constraints of varying degrees. These types of waste land

comprises severely eroded lands, salt affected land, area under shifting cultivation, degraded

forestland, degraded non- forest plantation land. Defective water and land waste and

unproductive and the create environment destruction. However the main causes of

destructions are deforestation, overgrazing, over cultivation, unskilled irrigation.

The first strips hastening the process of soil erosion and land degradation. The

deforestation is related to big multipurpose projects in hilly and plain areas mining for

minerals and energy exploitation, land use for agriculture, demand for timber for industry and

railways, firewood for domestic pay uses. Generation the over cultivation is related to

explosive population pressure on land and overgrazing is due to excess animal population and

uncontrolled breeding. The unskilled irrigation causes problems of water logging and salinity.

In the dry land areas when the farmers grow crops and anticipate rainfall especially at critical

stages of crop period. If the rain does not provide irrigation, the farmers do not even get the

amount spent for seed, ploughing and other inputs made for cultivating the crop. If it happens

for 2-3 years continuously, he is not interested in cultivating his land and the land becomes

fallow and degraded in due course through erosion. This can also be commonly observed in

rainfed submnontaneous Punjab.

Waste land management

58

Due to various causes wasteland are increasing rapidly and a day may come when the

total ecology of soil will collapse to control it. Some appropriate measures are required to

stop this and revert to the original slope.

Hyper urbanization and accumulation of ecological refuges on concentrated places

and development activities are also increasing the area of the waste land.

Hence, prevention of developing waste land and their management is needed for meeting the

future demands of increasing population. Thus the challenges are many, which add to the

shrinking natural resources of which land is the most important one. We look at the land with

reverence as ‘Mother land’. But She is the one who has been most neglected.

The various development programmes such as soil and water conservation measures,

wasteland development work, drought prone area programme etc., are needed to be

implemented. In order to take up the development work in the wastelands or fallow lands, the

following procedures may be adopted for the successful implementation of the programme.

1. Select a watershed having an area of 1000 – 5000 ha, or a micro-watershed of only

100-500 ha.

2. Each watershed is a distinct feature and hence watershed development programme

should be prepared for each watershed with involvement and cooperation of rthe

people of the watershed and specialists i.e., soil and water engineer, agronomist and

horticulturist, Forestors and animal husbandry.

3. The various soil and water conservation measures needed in the watershed including

in-situ soil moisture conservation can be planned and executed.

59

4. Training may be given to the farmers on soil and water conservation, water

harvesting, water management and tree growing techniques. In addition, they can be

taken to demonstrate the successfully implemented areas.

5. Marketing the produces should be planned and action should be taken in the

beginning of implementing the project.

There is urgent need to manage the waste lands and fallow lands so that we can produce

food grains to feed the nation in a sustainable way. The approach of watershed involving

participation of villagers is the best option. This venture of watershed development is

viable and will surely help in increasing the living condition of the poor farmers and also

generate large scale employment for rural youths.