THE momentum of agricultural growth and the level of adoption of technology in Pakistan have not been sustained. Stagnation in yields is accompanied by increasing costs of cultivation.

The natural resource base is under great stress. The sectoral policies, especially policies related to natural resources are outdated and lag behind the socio-economic changes that have altered the pattern of resource use.

Resource degradation is arising from distorted policies that may lead to divergence in private and social costs. Electricity for tube well operations is now priced at relatively lower annual rate, leading to overuse of poor quality tube-well water which is contributing to soil salinity.

The information base on which farmers make decisions is inadequate with respect to rapid changes in soil and water quality variables by moving to more sustainable practices such as integrated nutrients and pest management and more diversified crop rotations.

Public sector research is also biased towards development of technologies based on packages of modern inputs, and neglecting research on public goods such as integrated crop management and crops that can enhance diversification and sustainability of production systems.

Since independence, the area of land under cultivation has increased by approximately 40 percent. The country is approaching its physical limits. Of the total surveyed land area, less than 20 per cent retains the potential for intensive agricultural use, while about 62 per cent is classified as having low potential for crops, livestock, and forestry production.

Overall, the land categorized as cultivable represents almost less than one-quarter of the country’s total area. Today, nearly all of this land is already under cultivation. Very little additional land is available for the expansion of agriculture.

Shortage of arable land does not, of course, preclude an increase in agricultural production. Practices such as double-cropping, increases in labour productivity, and better technical inputs can boost output. But a number of forces have combined to prevent the realization of the country’s full agricultural potential. These include poor water management practices, a system of absentee landlords, the fragmentation of landholdings, poor access to capital, poor technology transfer to farmers, and a lack of information concerning the use of agricultural inputs, such as fertilizers and pesticides. The heavy use of fertilizers, particularly during the 1960s and 1970s, has also left soils deficient in number of nutrients essential to plant growth.

Approximately 40 per cent of the land in the central-western parts of the country was affected by light water and wind erosion, a loss of topsoil, and some terrain deformation. In the southwest and along the southern coastal parts, wind-eroded and salinized soils have predominated.

Desert soils, highly salinized soils, and some severely eroded areas are found along the Indo-Pakistan border, and soil in the lowlands of the Indus River valley have suffered from salinization. Meanwhile, lands in and around the north eastern parts of the country have been classified as “stable” under normal conditions.

The most important causes for reduced land productivity have been water and wind erosion, salinity and sodicity, water logging, flooding, and loss of organic matter. According to one finding, 17 per cent of surveyed soils (which include most of the soils usable for agriculture, forestry, or ranching) were affected by water erosion, 7.6 per cent by wind erosion, 8.6 by salinity and sodicity and 8.6 percent by flooding and ponding; fully 96 percent suffered from less -than -adequate organic matter. These problems often occurred simultaneously and produced synergistic impacts on agricultural productivity.

The salination/sodication of soils has been an outcome of low quality water used for irrigation. High temperatures have induced evapo-transpiration at rates much higher than the rainfall resulting in accumulation of salts in the surface layer of soils rendering them unproductive.

The pollution impacts and contaminant load both in type and quantity have increased in soils due mainly to technological progress and industrial development. The waste effluent from dwelling sites is discharged into sewage system and is ultimately disposed into rivers from where it again reaches the irrigated fields.

Whereas farmers consider the use of sewage for irrigation as cost-affective, administrators take it as a viable option for sewage disposal. The use of sewage water for irrigation purposes, on the other hand, has contaminated the soils and crops with heavy metals and high salt contents.

Pakistan’s water sources are also limited and the critical water shortages lead to power break downs and to inadequate supplies of irrigation water for the main crop-growing seasons.

The existing irrigation system is highly inefficient. Of the total inflow of 131 MAF in the Indus basis system, water available for irrigation through canals is about 97.5 MAF. The means that some 33.5 MAF water is lost in seepage and evaporation from canals and watercourses. This loss is a major cause of waterlogging and salinity of soils in the Indus Basin. Vertical pumping systems used for drainage have also proved to be unsustainable: the recycled water contains chemicals that have produced sodicity and reduced life of pumping machines.

No serious effort has been made to develop a drainage system to parallel the irrigation system. In Pakistan there are about 531,344 tube wells pumping about 49.50 MAF, out of which some 30-40 per cent water is regarded unsuitable for irrigation purposes. As such, tons of salts are pumped up in the process. The salts have decreased crop productivity in the prime lands in ‘canal command area’. The result is lower crop productivity.

In addition, the mushroom growth of tube wells in the private sector during the past decade has resulted in lowering water table. Irrigating lands with water regarded unsuitable for crop cultivation have adversely affected crop productivity. About 70-80 per cent of pumped ground water is found hazardous and entirely unsuitable for irrigation. In short, soil and water quality has deteriorated over time.

Average soil organic matter, which was lower than one per cent during early 1970s, deteriorated at an average annual rate of 2.3 per cent, (or a decline of over 33 per cent) during 1980’s and early 1990s. Similarly, there has been an alarming increase in the tube-well water quality, reflected in a significant increase in residual carbonates and electrocoductivity of tube-well water. Residual carbonates have almost doubled over years and farmers are increasingly tapping poorer quality groundwater

Over the past 75 years, forests have also decreased from 14.2 to 5.2 per cent (approximately 4.57 million hectares) of Pakistan’s total land area, with less than three per cent currently under tree cover. The negative consequences of uncontrolled forest exploitation are obvious. They include serious soil erosion and sedimentation, desertification of once-productive upland areas, the stilting up of waterways in the plains (making them more prone to flooding), and marked scarcities of fuel wood.

The decline in tree cover has resulted in a large reduction in watershed and reservoirs efficiency. These processes have major implications for the availability of water for irrigation and power generation. Indeed, large deficits of water and electricity are predicted in future, with considerable impact on agriculture and the economy.

Although use of pesticides is a main weapon for controlling harmful insects, weeds and diseases and boosting up production of various field crops, the indiscriminate use of pesticides has created serious problems such as resistance in certain insect pests, resurgence and outbreaks of secondary pests in addition to serious hazardous effects on human/animal health, beneficial marine fauna etc.

Excessive and indiscriminate use of pesticides has also created serious problems in human beings. Direct intake of pesticides through freshly sprayed vegetables and fruits, without considering their residual period, have created serious health hazards. Suffocation and vomiting are some of the common problems faced by passengers passing through cotton growing areas during spray periods. According to a 1998 United Nations report, as many as 500,000 Pakistanis suffer annually from poisoning due to agro-chemicals, of those, at least 10,000 eventually die.

Pakistan was at the forefront of Green Revolution in the late 1960s and early 1970s, in which farm machinery, pesticides and fertilizers, irrigation and the replacement of traditional crops with high-yielding varieties dramatically increased productivity. The land is now increasingly unable to support burden of intensive agriculture.

Crop yields – and water resources are declining alarmingly, and some lands are close to becoming barren. Many farmers are heavily in debt from their investments in new equipment and reliance on chemicals, and rural unemployment is increasing.

Intensive farming practices, particularly with wheat and rice, have virtually mined nutrients from the soil. Heavy use of fertilizers has disastrous effect: excess nitrates have leached into groundwater and contamination of groundwater with nitrates has increased dramatically. As such, the cultivable lands have become sick through over-application of chemicals.

Environmental degradation related to agriculture has been the product of technological and policy failures. High-input technology has created onsite second-generation effects that can only be corrected by improved research, development and extension (RD&E).

In less developed areas, the lack of appropriate technology has been a major source of environmental degradation. Lack of appropriate policy and institutions, as well as lax law enforcement, are main sources of external costs and the wasteful use of resources.

The sustainability of agriculture will depend on the prudent use of natural resources and careful considerations for the environment. The natural resource base is under great stress, likely to increase as the population continues to rise. Investment in environmentally sensitive technology is needed to ensure sustainability. The current constraints related to natural resources are not the result of limits on supply but rather of managerial and institutional problems.

From a policy perspective, there is a need for public and private initiative on several fronts-increased investment in resource management, research and extension, research to develop diversified and more sustainable cropping patterns and rotations, removal of price distortions on key inputs, especially water, and special incentives to invest in inputs such as gypsum that can counteract the problem of poor quality tube-well water. Such policy interventions may be rewarding if they can reverse the trend in resource degradation. However costs of such interventions have to be considered against potential benefits, before making definite policy prescriptions.

(The author is Chairman, Department of Marketing & Agribusiness at the University of Agriculture, Faisalabad.)