8 important Sources Responsible for Environmental Pollution



There are a number of sources other than fertilizers, which are responsible for environmental degradation. These include livestock and human excretion in rural areas and leaking septic systems, sewage, combustion of fossil fuels in motorcars and other vehicles in urban areas.

Industries that use nitrates in their manufacturing processes such as meat curing, production of explosives including fire crackers, heat transfer fluid etc. may also release substantial nitrates in their effluent water. Precise estimates on all these are not available. The available information is briefly discussed.

Foodgrain Production in India

India's foodgrain production has an impressive record of growth from a mere 50 million tonnes (mt) in 1950 (population 360 million) to 200 mt in 2000 AD. This growth, kick started by the Green Revolution, lost its momentum during the 1980s.

In retrospect, we have learnt that the energy-intensive Green Revolution relying primarily on a few high-yielding crop varieties is unsustainable and that it has polluted and exhausted the soil water system.

During the 1990s, in spite of good monsoons year after year, the growth rate of grain production haltingly rose by 1.7 per cent per year compared to 2.6-3.5 per cent during 1960-1980' while the population grew at 1.9 per cent. Further, a worrying factor is that over the last four years, the annual production is hovering close to 200 mt only.

These days we rightly take pride that we are self-sufficient in grain production. But we must not forget that hidden in this statement is the fact that it is at the cost of the hunger of 350 million of our people in poverty.

The Challenges

(i) Population

Currently, our population is one billion and we are growing at the rate of 1.9 per cent per year. For the year 2025, the UN Medium Projection is 1.392 billion. It is clear that, in future, the grain demands depend strongly on how well we control population growth.

(ii) Grain land

Land is a fixed resource. The gross cropped area in India is 191 million hectares (m.ha) and the net cultivated grain area is only 124 m.ha. Although over the last 10 years the cultivated grain land area has hardly increased, it is widely believed that it may shrink in future due to soil erosion, urbanization and human settlements, commercial agriculture, laying new highways and rural road networks and migration of farm labour in search of employment.

The high population density, rural poverty and scant pastureland for the 450 million heads of livestock also bring pressure on land and forests. Furthermore, it is important to note that the per capita arable land available in India dipped from 0.36 ha in 1960 to 0.2 ha in 1990 and is forecast by Population Action International Report 1995 to decrease alarmingly further to 0.12 ha. For comparison, Western type diet including pastureland requires 0.5 ha per capita.

(iii) Soil degradation

The Green Revolution has degraded the soil-water system and depleted soil fertility due to a variety of reasons.

It has also led to salination of 8 m.ha of irrigated cropland and water logging in some parts side by side the neglect of dry land farming and soil erosion are continuing threateningly till today. The present degraded state of irrigated and rain-fed agricultural land is a matter of grave concern for increasing productivity.

Restoration of the degraded cropland is inescapable for the future but it is going to be capital-intensive.

(iv) Water availability

Water is yet another fixed natural resource. The annual per capita water availability in India was 5277 m3 in 1955, which declined to 2451 m3 in 1990. According to World Bank Report 1998, it sank further to 1957 m3 in 1995.

The projection for 2025 by the Population Action International Report is 1392 m\ well below the water stress limit of 1700 m3.

Acute variations in water availability in different parts of the country (in 1990 the water use in Rajasthan was a meagre 562 m3, a state of absolute scarcity) and the dangerously falling water table are other major concerns for the future. Of the net sown area of 142 m. ha, only 48 m.ha are irrigated.

The rest 94 m.ha of rain-fed fields account for 90 per cent of pulses and coarse cereals, 53 per cent of rice and 15 per cent of wheat with a frighteningly low yield of hardly 1 tons per ha.

It highlights the importance of enlarging the irrigated grain land even if it is capital-intensive foodgrains in 2025; it corresponds to an annual growth of 5 mt. Considering the wisdom of planning for a modest exportable surplus and allowing for the possibility of a higher per capita direct consumption rate with improving economic performance, a target of 350-375 mt. does not seem unreasonable to aim for at the present time.

(v) Calories and nutrition

Rural people in India traditionally depended on course cereals, pulses and fish for their intake of calories and nutrition. While the average intake of calories is marginally satisfactory, the consumption of proteins, which was 64 g of pulses per day in 1951-1956, has dropped below 40 g in 1998 compared to the WHO-FAO minimum of 80 g per day.

Even after allowing for additional intake through fish, meat, milk, etc. the daily consumption rises only to 55 g. The average intake of vitamins and other micronutrients is also grossly inadequate.

This hidden hunger stealthily wreaks havoc on children's growth and leads to acute malnutrition among the people. The quality and quantity of grain production using new hybrids to be developed is a decisive factor in the amelioration of protein and nutrient inadequacy in future.

(vi) Fertilizer use

The traditional use of organic manure was almost phased out with the introduction of chemical fertilizers heavily subsidized by the government and widely promoted by the industry.

Even so, the prevalent average annual use of 69 kg per ha of chemical fertilizers is grossly inadequate to restore the nutrient content of the degraded soil and compensate the heavy intake by high-yielding hybrids.

This may be compared with the use of 366 kg per ha by China. It is said that the 'miracle rice' with a potential to yield 10 tonnes per ha will need a minimum of 200 kg of nitrogen per ha together with other micronutrients. From the foregoing it would also have become evident why our yield is so low.

(vii) Productivity or Yield of foodgrain

Our average grain yield of 1612 kg per ha (i.e., 200 mt from 124 m.ha) is one of the lowest among the large countries of the world. The reasons for this, as we have already seen, are many. However, our great asset of having perhaps the largest area of arable land in the world could be converted into a unique advantage.

If the productivity in China is more than double than that in India, there is no reason why we cannot meet our long-term demands by doubling the present productivity in the next 2-3 decades.

(viii) Other challenges

In addition, we face problems some of which are listed here: (i) as the economy improves, it is expected that the meat-eating diet of the people will burgeon. It is forecast that by 2020, the demand for grain as livestock feed will soar to 50 mt; (ii) It is estimated that of the 42,000 folk land races in rice that originally existed, only about five per cent are extinct.

This reduces our options for selective infusions of favourable hereditary qualities in new hybrids; it also emphasizes the urgency of measures for conservation. If we are to counter the unprecedented impacts of global warming India must take wide-ranging anticipatory action in the agricultural sector.

Yet other factors that must receive equally important attention are need for greater support for rural infrastructure, post-harvest management, strengthening R and D in agriculture including plant biotechnology, empowerment of farmer's particularly rural women and farm policy reforms.