*Corresponding Author: Mukhtar Ahmed, Pir Mehr Ali Shah Arid Agriculture University Rawalpindi Shakeel Ahmad, Bahauddin Zakariya University, Multan-60800, Pakistan

E-mail: mukhtar.ahmed@wsu.edu; ahmadmukhtar@uaar.edu.pk

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Science, Technology and Development 37 (3): 113-121, 2018 ISSN 0254-6418 / DOI: 10.3923/std.2018.113.121 © 2018 Pakistan Council for Science and Technology

Agricultural Land-Use Change of Major Field Crops in Pakistan (1961-2014)

1Shakeel Ahmad, 1Atique-ur-Rehman, 1Maryam Ejaz, 1Zartash Fatima, 2Mustafa Kan and 3,4Mukhtar Ahmed

1Bahauddin Zakariya University, Multan-60800, Pakistan

2Ahi Evran University, Kirsehir-40100, Turkey 3Washington State University, Pullman, Washington-99163, USA 4PMAS-Arid Agriculture University, Rawalpindi-46300, Pakistan

Abstract: This study was conducted to analyze the fate of agriculture land-use change (LUC) for major crops of the country viz. rice, wheat, maize, cotton and sugarcane, during 1961-2014, grounded on previously available data. Improvement in area and yield was a result of the use of high yielding cultivars and government policies and strategies of fertilizer-use during the period. Fertilizer-use in all major crops increased from 1961-2014, however, its efficiency with time decreases significantly. Per capita production of all major crops improved during 1961-2014, illustrating that more population was engaged in agriculture during this period and overall cereal production boosted during this time. Similarly, an increase in production per unit area and yield per capita was observed because of increased input, particularly chemical fertilizer during 1960s. However, a drop in yield per unit chemical fertilizer appears to be an outcome of fertilizer satiety, soil problems, natural hazards like floods, earthquake, less availability of irrigation, as well as, economic and social issues. The problems of increasing industrialization, urbanization, and inadequate reclamation of land resources, growing food demand can be overcome principally by augmented land productivity. Current study may help policy makers to design sustainable land-use policies for future. Key words: Wheat, Rice, Maize, Cotton, Sugarcane.

INTRODUCTION

Land-use change (LUC) in agriculture sector in Pakistan is very important as agriculture is the backbone of economy. It is the second largest sector, which contributes 19.8% to GDP and supports 42.3% of labor force (GOP, 2016). Natural resources, e.g., soil, water, crop, biodiversity and land cover, have been affected by land-use, which have significant influence on soil and water quality, global climate and poverty (Houghton et al., 1991; Houghton, 1994; Turner et al., 1995; Keswell and Carter, 2014). An increase in population and intensive agriculture is driving the causes of land-use and land-cover change (Verburg et al., 1999). Patterns of land-use in Pakistan have developed through centuries and that may be attributed to different environmental and physical factors (Landform, soil, climate, water availability) as well as human factors (Population size, growth, economic demands, and cultural practices or customs) (Fig. 1). Agricultural land-use is mainly determined by the distance to market (Von

Thunen, 1960) and soil fertility pattern (Ricardo, 2002). LUC is exaggerated strongly by socioeconomic elements, i.e., land policies, migration, urbanization, agrarian product prices along with world trade (Fig. 1). In Pakistan, a great interregional variation evidently illustrates the effect of these factors. For instance, Baluchistan, the biggest province, has moderately big rangelands used for grazing. On the other side, Northern Areas and Khyber Pakhtunkhwa (KPK) have high altitude regions, with high snow coverage (13%), which is absent in other provinces. Similarly, these regions have 17% forest coverage as compared to Sindh (6%), Punjab (4%) and Baluchistan (1.5%). Contrary to this, Punjab and Sindh have 50% and 33% agricultural land, respectively, with widespread canal irrigation system.

LUC plays an important role in the study and analysis of globally changed scenario today (Shirazi, 2013). The growing socio-economic requirements of rising population is alarming and to overcome the

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increased demands, the pressure on available land resources will be high (Seto et al., 2002). Overwhelming stress may result in misconduct of issues related to agriculture, forest and water resources, leading to severe environmental problems (Shirazi, 2013). LUC may be a result of natural modifications, like biodiversity alteration, deforestation, global warming and natural disaster; earthquake and flooding (Mas et al., 2004; Dwivedi et al., 2005). Study of such variations in agricultural land can offer a better option for making a policy decision for future resource management and planning (Fan et al., 2007; Fatima et al., 2018; Prenzel, 2004).

Fig. 1: Government policies and seed acts during 1959-

2014 in Pakistan.

There are a number of studies related to LUC in Pakistan, but none of these examined land-use-change on major field crops (wheat, rice, maize, cotton and sugarcane) (Aslam et al., 2018; Shirazi, 2013; Bhalli et al., 2012; Batool et al., 2015). Furthermore, few studies have analyzed the consequences of commercial fertilizer-use on key cereal crops related to LUC. This study is planned with the objectives to analyze LUC for the major crops in Pakistan, during 1961-2014; to survey the dynamics of chemical fertilizer used in Pakistan agriculture, especially in major crops and its efficiency in terms of output or yields ha–1, yield/unit commercial fertilizer-use. Also, it aims at taking a rough estimate of yield per capita in association with LUC in the major field crops, which may help to design policies related to LUC in Pakistan.

METHODOLOGY

1. Data collection

The prime data on Pakistan’s agriculture system (land-use, crop production, along with fertilizer-use) was collected from Pakistan Bureau of Statistics (PBS), Islamabad, which in its chapter of agriculture, reports statistics of agriculture, in general, and on all

field crops of Pakistan. However, the authors collected other relevant data on total fertilizer consumed each year, during 1960-2010, in Pakistan from the Earth Policy Institute survey (www.earth_policy.com). Current study is based on LUC and fertilizer-use-change for major arable crops.

This study included changes in area planted with major crops in Pakistan, during 1961-2010, constructed on the durable historical data. Similarly, data about fertilizer used in major crops and outcome of that fertilizer and the yield of major crops were analyzed. A summary of different agriculture-related policies and other socioeconomic factors during 1961 to 2014, was prepared. The time period was divided into decades, i.e., 1961-1970, 1971-1980, 1981-1990, 1991-2000, 2001-2010 and 2010-2014. The data about natural disasters, from early 1935 to 2014, was obtained. This data describes about human death, total affected people and financial loss as a result of each type of disaster.

2. Analysis of data

The yield/hectare and yield/unit commercial fertilizer-use for major crops, viz. rice, wheat, maize, sugarcane and cotton, during 1961-2014, was evaluated, in order to estimate the effect of LUC along with fertilizer inputs on field/arable crop production.

Yield/unit chemical fertilizer-use for different crops was calculated, using the formula (Tong et al., 2003):

Yield_Fert (t, yr) = Prod (t, yr)

Fert (t, yr) Eq. (A. 1)

Annual fertilizer-use on each crop was calculated by the following formula (Hall et al., 1998; Tong et al., 2003):

Fert(t, yr) = Fert(t, yr)Fert(c, 90)

Fert(t, 90)

Area(c, yr)A (t, yr) Eq. (A. 2)

where, Fert(c,yr) is the fertilizer-use for individual crop during individual year; Fert(t,yr) total national fertilizer-use during a year; Fert(c,90) the fertilizer used for individual crop during 1990; Fert(t,90) the total national fertilizer-use during 1990 (Pakistan Bureau of Statistics, 2018); Area(c,yr) the area used for individual crop during year; and Area(t,yr) is the total area of food crops during year.

Yield per capita was calculated according to Tong et al. (2003). A relationship between yield and fertilizer-use in each crop was made, using a sigma plot (SigmaPlot, 2018).

RESULTS AND DISCUSSION

1. Changes in area under major crops

Total land under major crops, i.e., rice, wheat, maize, cotton and sugarcane, during 1961 to 2014, in Pakistan, shows variations from early 1960s to 2010 (Fig. 2; Table 1). An increasing trend for area under cultivation was observed for these crops, which shows

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a better utility of land by these crops. However, among various crops, wheat was at the top during an entire period, and cotton and rice were also cultivated on big area as compared to sugarcane and maize (Fig. 2). In general, area under all major crops increased with the passage of time. Cereal prices, economic development and government policies were primary factors causing these fluctuations. The land area slightly increased from 1960 to 1970, for cereals (rice, wheat, maize) cotton and sugarcane. The greatest rate of increase was observed from 1967 and onwards (the period when “Green Revolution” was strongly adopted) for cereals and cotton, while for sugarcane, there were more fluctuations. The income of agricultural communities increased due to agricultural production in this era. During 1961-1965, the agricultural output increased 3-6% annually and it climbed further to 15% during 1967-1968. So, the

green revolution adopted during that period, motivated farmers to cultivate more land. The land area decreased in 1971, while Pakistan was in a state of war with India, however after war, it started increasing again. A crop-wise summary of land-use by major field crops is given in Table 1. During 1995-2000, area under wheat and rice increased in Punjab, Sindh, Baluchistan and KPK, respectively. Moreover, during this period, a major increase was in cotton in Baluchistan (240%). From 2001-2005, rice, cotton and maize cultivation increased in Punjab. Meanwhile, from 2006-10, area under cereals increased, viz. 4, 2.3 and 10.3%, in Punjab, while in Sindh 39.6% decrease in rice cultivation was observed (Table 1). On the other hand, sugarcane area increased in Sindh (5.1%) only. During this period, area of cultivation by all major crops decreased in Baluchistan and KPK (Table 1).

Fig. 2: Area (000 ha) of five major crops from 1960-2014 in Pakistan.

Table 1: Land-use change (%) in wheat, rice, maize, cotton and sugarcane for four provinces of Pakistan, during

1995-2010.

Provinces Wheat Rice Maize Cotton Sugarcane 1995-2000

Punjab +4.7 +22.5 +1.0 –3.1 +1.5 Sindh +3.5 –15.9 –33.3 –0.9 –5.9 Baluchistan –24.8 +11.7 –25.0 +240.0 0.0 KPK –8.8 +3.1 +0.9 0.0 +2.9

2001-2005 Punjab –19.5 +19.4 +37.7 +1.6 –4.9 Sindh +6.6 +10.7 –50.0 +16.5 –57.3Baluchistan –7.2 +53.8 +100.0 –5.0 –100.0 KPK –3.5 +1.6 –9.1 0.0 –2.9

2006-2010 Punjab +4.0 +2.3 +10.3 –10.6 –5.6 Sindh +16.6 –39.6 +50.0 –19.8 +5.1 Baluchistan –16.6 –1.5 –16.7 –26.2 0.0KPK –3.8 –24.6 –18.0 0.0 –13.7

The 1980s decade was good for cotton as some

enhanced varieties were introduced and there was an increase of 24% in area under cotton cultivation by the end of this decade. During this period, the

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government increased support prices for major crops, yet there was a decrease in land area for cereals and sugarcane in the mid-decade, probably due to nitrogen fertilizer subsidies abolished by the government in 1986. Support price of wheat also decreased at the end of the decade. At the start of last decade of century, land for wheat increased as support price for wheat was increased but area for wheat and cotton yet had great fluctuations for cotton being the major decrease in 1994-95. For all other crops, there was a stable increase in area with slight deviations. During 1998-2002, Pakistan was struck by the most devastating drought of its history. This drought in Baluchistan affected about 1.5 million people and killed some 2 million animals and 127 people in Sindh. Effects of drought can easily be seen in land-use reduction by all major crops during this period, however, sugarcane had sustained its cultivation land area. After the removal of the effects of drought of 1998-2002, there was an increase in the area of these crops. Two more droughts (2004-2005 and 2009-2010), that hit Pakistan during this decade, damaged crop production

in Pakistan. Then the impact of monsoon-induced flood of July 2010 was devastating destroying about 3.6 million hectare of standing crop, infrastructure and agricultural machinery. According to FAO (2010), production loss of cotton, paddy and sugarcane was 13.3 million mt.

2. Yield per hectare

The production per unit land area increased over this period (Fig. 3). A significant increase in yield started during 1960’s, when new and high-yielding cultivars of major crops were introduced, i.e., green revolution. Although, cotton yield also improved during this time but it was not as much as with other crops, especially wheat and rice. Average yield cereal of 954 kg ha–1 during 1961, however, augmented to 1507 kg ha–1 in 1980, 2029 kg ha–1 in 2000, and to 2890 kg ha–1 in 2010, with an average rise of 4.06% year–1. This rise was 2.9% year–1 during 1961-1980, 1.7% during 1980-2000, and 4.24% during 2000 to 2010 (Fig. 3).

Fig. 3: Yield (ha–1) of five major crops during 1960-2014 in Pakistan.

Yield of rice during 1961-2010 increased (1011-

2031 kg ha–1), while for wheat, maize, sugarcane and cotton, the increase was 818-2833 kg ha–1, 1032-3805 kg ha–1, 32,336-56,000 kg ha–1 and 232-731 kg ha–1, respectively. An annual increase for each crop was 2.01, 4.92, 5.37, 1.46, and 4.3%, respectively (Fig. 3). After the year 2000, yield of rice boosted and from 2000 to 2014, it was almost double (Fig. 3). The main reason for this yield improvement was an increase in support prices of rice. Subsidy on fertilizer especially the phosphate fertilizer was announced by the government during 2006, and this policy change resulted about an increased production of different

major crops. Moreover, availability of chemical fertilizer improved ensuring timely use of fertilizer according to crop requirement. Ultimately, the yield of all major crops increased by these measures.

3. Yield/unit commercial fertilizer

Overall, fertilizer used/unit area has been increased for all the crops (Fig. 4). Chemical fertilizer used per unit area was increased from 3.17 kg ha–1 during 1961 to higher than 30 kg ha–1 during 1980 and to higher than 88 kg ha–1 during 2010. Overall fertilizer used for wheat augmented from 19.9 kt during 1961 to 1035.9 kt during 2010, for rice from 1.04 kt during 1961 to 58.56 kt during 2010, in maize

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from 0.16 kt during 1961 to 9.64 kt during 2010, in sugarcane from 0.42 kt during 1961 to 26.88 kt during 2010, and in cotton from 2.39 kt during 1961 to 132.9

kt during 2010. Full fertilizer used in country augmented from 73 kt during 1961 to 1079 kt during 1980 and to 3942 kt in 2010 (Fig. 4).

Fig. 4: Fertilizer use for five major crops during 1960-2010 in Pakistan.

Yield of crops under this study showed a positive

correlation with fertilizer-use between 1961 and 2010, i.e., the yield increases as the fertilizer-use increases (Fig. 5). Fertilizer-use increased from 3.17 kg ha–1 in 1961 to 30.5 kg ha–1 in 1980 and to 67.38 kg ha–1 in 2000 with a corresponding increase in mean yield of crops under study from 954 kg ha–1 in 1961 to 1507 kg ha–1 in 1980 and 2029 kg ha–1 in 2000. In 2010,

commercial fertilizer-use was above 88 kg ha–1, and yield increased to over 2889 kg ha–1. Other factors like machinery, irrigation, organic fertilizer, improved varieties, pesticide-use and other management techniques also caused an increase in yield but commercial fertilizer-use seemed to be the leading reason causing an increase in yield.

Fig. 5: Relationship between fertilizer-use and yield of five major crops during 1960-2012 in Pakistan.

However, the yield/unit fertilizer-use decreased

markedly from 1961 to 2010 (Fig. 6). Productivity of wheat decreased from over 202 t/t in 1961 to 40.8 t/t in 1980 and to 24.3 t/t in 2010. Similarly, rice

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productivity decreased from 1174.7 t/t in 1961 to 188.8 t/t in 1980 and to 82 t/t in 2010. For maize, sugarcane and cotton, a decrease in productivity was

from 2998, 34167, 135 t/t in 1961 to 384, 2057, 14.7 t/t in 2010, respectively (Fig. 6).

Fig. 6: Dynamics of yield per unit fertilizer-use on rice, wheat, maize, cotton and sugarcane during 1960 to 2010 in

Pakistan.

4. Cereal yield/capita

Total production of cereals considerably increased in Pakistan from 1960 to 2011 (Fig. 7). In 1960, it was 19 million tons and it improved significantly from 1965 to 1970 (the green revolution era). However, the increase in yield from 1970 to onward was not as much as in 1965 to 1970 (Fig. 7).

An average production of cereals per capita increased considerably in Pakistan, from 1960 to 2011

(Fig. 7). It was only 126 kg in 1961, but improved as 185 kg in 2011, with almost 175 kg per person in 1990. A significant improvement in per capita production was observed during 1970’s due to the introduction of high yield cultivars of cereals and land reforms executed by the government. During this period, improvement in per capita production was 28% (Fig. 7).

Fig. 7: Total production and production per capita during 1960 to 2014 in Pakistan.

A careful analysis of data indicates that the area

of crops under study had fluctuations from 1961-2010, as explained. In Pakistan, an area in crops

production under study is affected by many factors including social factors (e.g., land reforms, inheritance system of land), environmental factors,

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natural disasters (droughts and floods) and economic factors (growers), buying power for inputs, support prices and urbanization), erosion, deforestation, desertification, soil and water pollution, salinization, etc. Product prices, subsidies on input and government policies are important driving forces for LUC as discussed earlier. Other instances include the adoption of green revolution. When a farmer gets a good price of a certain crop then more farmers tend to grow that crop increasing its planting area, while the trend is opposite when they did not get enough return from a certain crop.

Rapid urbanization and industrialization caused a major loss of agricultural land. In early 1990s, several different industrial regions had been developed largely on agricultural land decreasing the cropping area. Also cities have been expanded by building new housing colonies to accommodate an ever increasing population while sacrificing good agricultural land. The absence of basic living requirements like health facility, safe drinking water, education, etc. and less economic benefit urged farmers to move to a city and adopted other better paying occupations. Rapidly increasing population together with land inheritance system in Pakistan has resulted in small farm size thus causing the use of new technologies and machinery inevitable.

Government policies, e.g., seed policy, subsidies and support price (affecting the input purchasing power) and income of farmers influence the choice of crop and area planted. Water scarcity is one of the most important limiting factors in Pakistan. Rainfall distribution and intensity is erratic. Irrigation system is inefficient as out of 92 MAF water entering the canal irrigation system, only 65% reaches field head (Saeed, 1994). A large portion of land can be utilized only with irrigation.

Natural disasters, like severe droughts of 1998-2002 and 2004-2005 and severe flood of 2010, influenced strongly land-use pattern in Pakistan. Globally both temperature and CO2 level is increasing, which may increase yield of cereals (particularly rice), while, an increase in temperature may lead to a decrease in yield (Mathews et al., 1997; Ahmad et al., 2016; Ahmed et al., 2016; Ahmad, 2017a; Ahmad, 2017b). Climate change influences the cultivation patterns and growth of plants (Bajwa et al., 2015).

In this study, an analysis of an increase in yield due to fertilizer-use and some other factors, like irrigation, management, etc., was done and the use of fertilizer seems to be the most influencing one. In 1961, fertilizer-use for all crops under study was 24,000’tons by 1980, it reached to 343.7,000’tons and to 1264 000’tons by 2010, while the yields were 35429, 44083 and 65400 kg/ha for the same years. The fertilizer-use increased 104% each year during 1961-2010, however, a boost in fertilizer-use was observed during green revolution.

This study showed that yield/unit fertilizer-use has been decreasing (Fig. 6). Improper fertilizer use leading to soil degradation has been an important reason for this trend. Soil erosion remains to be a severe problem in Pakistan. Improper land-use has led to heavy soil erosion in barani lands. Water and wind erosion has affected 11 and 3-5 million hectares, respectively. Water erosion further leads to the problem of sedimentation in major reservoirs declining their capacity and affecting irrigation system and hydropower generation. Wind erosion removed 28% of total soil loss (Khan et al., 2012). Such high values of erosion can be reduced if there is more vegetation on land while forest covers only 5.2% area in the country which is further decreasing by 3.1% annually.

About 11 million hectares are waterlogged with 5-10 feet watertable depth in Pakistan. The soils affected by salinity and sodicity comprise 5.3 million hectares. Drainage capacity of the soils has been reduced by salinity, sodicity and water logging, resulting in less soil fertility, lower crop yield and biodiversity loss (Zia et al., 2004).

During 1947-2014, Pakistan faced many natural disasters in the form of floods, earthquakes and storm, which caused not only killing of people but also heavy financial losses (Table 2). Adverse climatic conditions also affected agricultural productivity. Prolonged spells of drought have been affecting Baluchistan, Sindh and Southern Punjab for the last three years, adversely impacting about 2.2 million people and 7.2 million heads of livestock (Khan et al. 2012). Devastating floods of 1973, 1992, 2010 and 2014 not only caused severe damage to agriculture sector and national economy but also resulted in land degradation. Flood occurrence is becoming a regular feature in the country. Rainfall distribution is uneven spatially (less than 10 cm in some areas of Sindh and more than 50 cm in foothills of Himalayas) and temporally (67-75% in summer and 25-33% in winter) (Kurosaki, 2014). Pakistan has mostly irrigated agriculture but the system provides much less percentage of water requirements of crops. Therefore, crops are highly dependent on occurrence of timely normal rains. Meanwhile, 25% of total water available at field head is lost at field application stage due to improper application practices.

The declining yield per unit fertilizer is also because of improper ratios of the fertilizer added. Organic matter in soils is decreasing and very little efforts are made to maintain it. In order to improve agricultural harvests, growers need to add suitable chemical and organic fertilizer after soil test. Current analysis showed an inverse relationship between fertilizer-input-intensity and yield/unit fertilizer-inputs (Fig. 5). Ko et al. (1998) and Tong et al. (2003) observed the same inverse relationship between chemical fertilizer-input and yield of crops/unit fertilizer used. According to Ko et al. (1998), the yield per unit fertilizer can be increased by decreasing

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the intensity of both fertilizer and land-use, but with rapidly increasing population, it is not possible for Pakistan.

Table 2: Overview of natural disasters during 1947-2014, in Pakistan.

Category Earthquake Year NK NTA Damage

1 Earthquake 1935* 0.060 - -

2 Earthquake 1945* 0.004 - -

3 Earthquake 1974 0.005 - -

4 Earthquake 2005 0.073 5.128 5.200 1 Storm 1965 0.010 - - 2 Storm 2007 - - 1.620 1 Flood 1950 0.003 - - 2 Flood 1973 - 4.800 0.6623 Flood 1976 - 5.566 0.505 4 Flood 1977 0.001 - - 5 Flood 1992 - 6.184 - 6 Flood 1992 0.001 6.655 1.000 7 Flood 1998 0.001 - - 8 Flood 2005 - 7.000 - 9 Flood 2010 0.002 20.359 9.500 10 Flood 2011 - 5.401 2.500 11 Flood 2012 - 5.049 2.500 12 Flood 2013 - - 1.500 13 Flood 2014 - 2.276 2.000

*= Pre-partition of Indo-Pak subcontinent.

It is further observed that fertilizer-use is

increasing to improve yield from the existing land degraded by industrialization and misuse. It is becoming difficult to maintain self-sufficiency in feeding the increasing population with this strategy of increasing fertilizer-use as an increase in yield with increasing fertilizer ratio seems to be stagnant.

CONCLUSION

The estimation of LUC for major crops on historical basis revealed that area and yield of these crops increased significantly due to use of high yielding cultivars, government policies and fertilizer-use strategies. However, in order to bring sustainability in the yield of these crops designing/implementation of long term policies are needed by the policy makers. Similarly, the data presented in this study may be used at farm level for decision making for increasing and stabilizing yield. This information is also good for decision-making on agricultural management, such as, fertilizer-use and policy decision making on sustainable governance.

ACKNOWLEDGEMENT

The research work was financially supported by Higher Education Commission (HEC), Islamabad and Bahauddin Zakariya University, Multan, Pakistan.

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