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Biodrainage

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Credit Seminar on

BiodrainageCourse Incharge

Dr. G. Ravi Babu

Associate Professor & Head

Dept. of Soil and Water Engineering

By

Ch.AppaRao

BEM-12-001

INTRODUCTION

Biodrainage may be defined as “pumping of excess soil water

using bio-energy through deep-rooted vegetation with high rate

of transpiration.”

The biodrainage system consists of fast growing tree species,

which absorb water from the capillary fringe located above the

ground water table.

The absorbed water is translocated to different parts of plants

and finally more than 98% of the absorbed water is transpired

into the atmosphere mainly through the stomata.

This combined process of absorption, translocation and

transpiration of excess ground water into the atmosphere by

the deep rooted vegetation conceptualizes bio-drainage.

Merits of biodrainage over conventional drainage systems

Relatively less costly to raise biodrainage plantations

No maintenance cost from 3rd year onward

No operational cost, as the plants use their bio-energy indraining out the excess ground water into atmosphere.

Increase in worth with age instead of depreciation

No need of any drainage outfall and disposal of drainageeffluent

No environmental problem, as the plants drain out filteredfresh water into the atmosphere

In- situ solution of the problem of water logging and salinity

Preventive as well as curative system for waterlogging andsalinity

Combined drainage- cum – disposal system

Moderates the temperature of the surrounding by transpiration

and a cushion for moderating frost, cold and heat wave impacts

Helps in carbon sequestration and carbon credits

Mitigates the problem of climate change and contributes to

increased forest cover

Purifies the atmosphere by absorbing CO2 and releasing O2

Acts as wind break and shelter belts in agroforestry system

Provides higher income to the farmer due to the production of

food, fodder, fuel wood and small timber

Where to apply:

Thornburn and George (1999) observed that the evaporation

from the soil takes place up to a depth of 4 m (Fig. 1).

Fig. 1: Relationship between evaporation and water table depth in different soil

types

CASE STUDIES

Title Biodrainage to combat waterlogging, increase

farm productivity and sequester carbon in canal

command areas of northwest India

Scientists Jeet ram et al

Journal & Year Current science. vol.100 (11):1673-1680.

2011

Location Puthi village, hisar district, Haryana

Fig.2 land locked area of puthi research plot.

Fig.3 Layout of puthi research plot.

Table 1. Fresh shoot biomass of 22, 5-year and 4-month-old trees

of clonal eucalyptus tereticornis.

Table 2. Biomass and carbon sequestered by 5-yr and 4 month

old clonal E.tereticornis

Table 3. Transpiration of groundwater by trees of clonal

E.tereticornis

Fig.4 wheat yield obtained with and without eucalyptus

plantation.

Fig.5 effect of plantation on soil electrical conductivity of the

saturation extract (ECe)(ds /m) and ph of the soil saturation

paste (pHs).

Fig.6 Trend of groundwater table levels in (a) transect I and (b)

transect II at Puthi research plot during April 2005 and 2008

Conclusions

Four parallel strip plantations worked as bio-pumps andlowered the water table by 0.85 m in 3 years in canal-irrigated, agricultural, waterlogged fields located in a semi-arid region with alluvial sandy-loam soil.

The annual rate of transpiration by these plantations was268 mm against the mean annual rainfall of 212 mm.

These plantations generated 46.6 t/ha fresh biomass withbenefit-cost ratio of 3.5 and also sequestered 15.5 tcarbon/ha.

Lowering of water table and associated improvement byEucalyptus plantations increased by 3.4 times than theadjacent fields.

Title Biodrainage Potential of Eucalyptus

Tereticornis for Reclamation of Shallow

water table areas in North West India

Scientists J. ram et al

Journal & Year Agroforest Syst. vol.69:147-165.

2007

Location Dhob-bhali research plot , Rohtak district,

Haryana

Fig. 7 Location of (a) Haryana state in north-west India

and (b) Dhob-Bhali research plot in Rohtak district of

Haryana state

Fig. 8 Layout of Dhob-Bhali research plot. Legend. (•)

Observation well,( ) road,( IIIIII ) railway line and ( )

plantation

) road,

( IIIIII ) railway line and () plantation

Fig. 9 fluctuations of ground water table during 1974-2004 in

rohtak district.legend.(-o-) june and (-^-) October.

Fig.10 Trend of ground water table levels in the east-west

transect of Dhob-Bhali research plot during (a) pre-monsoon

season, (b) monsoon season, (c) post-monsoon season and (d)

winter season of 2004–2005

Fig.11 Mean trend of ground water table levels in the east-west

transect of Dhob-Bhali research plot during 2004–2005 and

2005–2006.

Fig.12 Trend of ground water table levels in the north-south

transect of Dhob-Bhali research plot during (a) pre-monsoon

season, (b) monsoon season, (c) post-monsoon season and (d)

winter season of 2004–2005

Fig.13 Mean trend of ground water table levels in the north-

south transect of Dhob-Bhali research plot during 2004–2005

and 2005–2006.

Fig.14 Trend of (a)ground water table salinity and ground water

table levels (b) soil salinity and ground water table levels and (c)

soil salinity of the zone of capillary fringe and ground water

table levels during may 2004 in east west transect. (.) ground

water table and (^) salinity.

Fig. 15 Fluctuations in g.w.t and g.w.t salinity during May

of 2004, 2005 and 2006. Legend. ( ) May 2004, ( ) May

2005 and ( ) May 2006

Conclusions

The average g.w.t. in the plantations was 4.95 m and the

average g.w.t. in the control located in the adjacent fields

was 4.04 m and hence, the drawdown of g.w.t. was 0.91 m.

Throughout the study of 2 years, the g.w.t. underneath the

plantations remained lower than the g.w.t. in the adjacent fields

without plantation.

The g.w.t. in the plantations was lowered up to a maximum

depth of 5.63 m below the ground level.

The spatial extent of lowering of g.w.t. in the adjacent fields was

up to a distance of more than 730 m from the edge of a plantation.

The sinker roots reached the zone of capillary fringe up to a

depth of 4.40 m clearly indicating that the Eucalyptus trees

were absorbing capillary water of the g.w.t.

Title Biodrainage for preventing waterlogging and

concomitant wood yields in arid agro-

ecosystems in north-western india

Scientists O P toky et al

Journal & Year Journal of scientific and industrial

research. vol.70 :639-644.

2011

Location Haryana Agricultural University, hisar

district, Haryana

Experimental site comprised of 30 acres (12 ha) ofwaterlogged land at CCS HAU farm square number1799-1800 along with Balsamand canal whichflows nearly in the east west transact.

With a long term view of reclaiming this abandonedwaterlogged site, biodrainage plantations have beenraised as strip plantations on field bunds which areabout 60 m apart from each other.

Field bunds were 2.9 m broad at base, 2.6 m broadat top, 0.45 m in height and extend to a length of150 m from north to south. Two rows of trees were

planted on each bund with a row to row distance of1.3 m. Plant to plant distance was 1.5 m inEucalyptus and 3 m in other species.

Fig. 16—Tree height and diameter at breast height (DBH) of

different tree species in September 2009 (CD 5%: Ht 73, DBH

1.7)

Fig. 17—Strip plantation of some representative tree species on

ridges at the field in university campus: a) Eucalyptus

tereticornis C-10; b) Eucalyptus tereticornis C-3; c) Tamarix

aphylla; and d) Prosopis juliflora (marked leaf area is difference

between C-10 and C-3 of E. tereticornis)

Fig.18 —Leaf area index of different tree species in September

2009 (CD at 5%: 0.17)

Fig. 19—Water table immediately beneath each strip plantation

with respect to fallow control bund

Table 5. water table fluctuations measured as mean of monthly

values from a well located 20m east of each bund during

experiments

Conclusions:

Tree species vary in their “biodrainage potential” as evidenced

by the extent of lowering of water table immediately beneath

the plantations.

Eucalyptus species has a higher biodrainage potential as

compared to relatively slow biodariners like T. Aphylla and

P.pinnata.

THANKYOU