In the previous blog we discussed:
3. Challenges Ahead
- Sustainable advances in biological productivity are essential for meeting the needs of both enhanced agricultural production and greater agricultural diversification.
- For this purpose, we need new agricultural technologies capable of raising the population-carrying capacity of land and water. Such techniques will have to be tailored to the following major land-use systems:
a) Mountain ecosystems, where damage upstream would have serious repercussions on downstream agriculture (e.g. Himalayas and the Indo-Gangetic agricultural region)
b) Coastal ecosystems, where it will be necessary to promote the integrated management of land and sea surfaces,
c) Sustainable intensification areas (could also be referred to as "green revolution" areas) which, with appropriate support from maintenance and anticipatory research can sustain intensive output of crops and livestock at high and rising levels of productivity
d) Semi-arid areas, where inadequate or unreliable rainfall coupled with over-exploitation leads to chronic land degradation
e) Arid areas, belonging to both the hot and cold desert categories, where sylvi-pastoral and Sylvi-horticultural systems of land use are ideal, and
f) Island ecosystems where changes in sea levels could have important implications.
Unsustainable management of the resource and environmental systems associated with such regions is having serious repercussions, as is evident from the following visible signs in many developing countries.
- Precipitous drying up of drinking water resources
- Vanishing forests, flora, and fauna
- Intensifying drought and floods
- Loss of grazing lands and growing degradation of land
- Deterioration of the quality of air and water
- Explosive growth of rural and urban unemployment
- Mushrooming of urban slums
It is the poor and the marginalised who suffer most from such environmental breakdown.
The nexus among people, resources, environment, technology and agricultural development is thus a closed one. FAO's estimates of total harvested land of different potentials are given in Figure 2. FAO's study, World Agriculture: Toward 2000, concluded from an analysis of 93 developing countries, excluding China, that nearly 60% of harvested land in 1982-84 belonged to the high potential category.
Unirrigated arid and semi-arid areas of developing countries accounted in 1983-88 for only about 9% of total cereal production and 6% of root and tuber production. Thus for achieving the production goals of the future, it will be essential to maintain and further enhance
the production potential of "sustainable intensification areas" and upgrade degraded land. In this context, it will be useful to consider briefly the present state of global land and water resources management.
- It is estimated that 30 to 50% of the earth's land area is degraded due to improper management. In particular, both the conversion of forest land for agriculture and exploitative agricultural practices have led to an increase in soil erosion over the past 25 years.
- The rate of soil erosion is almost imperceptible (1mm of soil loss in a storm amounts to 15 tonnes per hectare) and significantly exceeds its floor renewal rate (2.5 cm/500 years and at best I tonne per hectare per year).
- The rate of soil erosion in temperate countries is 10 to 20 times the soil renewal rate, while in the tropics it is almost 20 to 40 times.
- FAO's estimates suggest that approximately 6 million ha/year are becoming unfit for agriculture.
- In some areas, the productivity of eroded soils cannot be restored even at enormous costs (equivalent to the application of 2000 tonnes of quality soil per hectare, or 50 tonnes dry rotted cattle manure per hectare).
- Soil loss also leads to nutrient depletion.
- One tonne of good agricultural soil may contain a total of 4 kg. of nitrogen, 1 kg of phosphorous, 20 kg of potassium and 2 kg of calcium.
- Further, soil erosion results in a loss of organic matter which plays a pivotal role in improving infiltration, water retention, soil structure and cation exchange capacity.
- Organic matter and soil micro-flora and micro-fauna (including earthworms) are interdependent in maintaining soil quality and in promoting the recycling of nutrients and degradation of wastes.
- The World Commission on Environment and Development in its report, "Our Common Future" (1987) has drawn attention to the serious state of global water resources.
- Global water use has doubled between 1940 and 1980 and it is expected to double again by 2000, with two-thirds of the projected water use going to agriculture (WCED, 1987). Yet 80 countries, with 40 percent of the world's population, experience serious water shortages even now. There will be growing competition for water for irrigation, industry and domestic use.
- River water disputes will multiply between nations and within nations. No easy solution is in sight unless solar desalination of seawater becomes an economic proposition.
- Concurrently steps to increase national efforts in saving and sharing water in the rainfed areas are important.
- The most serious component of potential changes in climate is precipitation. Efforts in enhancing the efficiency of water harvesting and on-farm water management are therefore essential.
- In areas of intensive agriculture, problems of salinity, sodicity and waterlogging, as well as the incidence of malaria, schistosomiasis and other waterborne diseases, are becoming important.
- Groundwater resources are being adversely affected qualitatively by the excessive use of mineral fertilizers and pesticides. Most countries are yet to develop policies for regulating groundwater use in accordance with the recharge capacity of the aquifer.
iii) Living aquatic resources:
- The world catch of marine living resources is now growing only I to 2 percent annually and is approaching its estimated maximum sustainable yield of 100 million tonnes (Figure 4).
- Since as much carbon is fixed in the sea as on land, it is important that coastal zones are subjected to an ocean capability analysis, on the model of land classification systems currently in use.
iv) Biological diversity:
- Biological diversity is the foundation upon which the edifice of sustainable advances in biological productivity can be built.
- Recent advances in molecular biology and genetic engineering, which render the transfer of genes across sexual barriers possible, have further enhanced the economic and ecological value of global biological wealth.
- Unfortunately, serious losses are now occurring at all the three levels in which biological diversity manifests itself, namely intra-species and ecosystem levels, due largely to the destruction of habitats rich in genetic resources, such as tropical rain forests.
- Recent estimates put the rate of deforestation in the tropics at 17 million ha or 1 % per annum (TFAP, 1990). The disappearance of forests also reduces the extent of carbon absorption on the earth. The carbon emission-absorption balance is IIIlIN upset.
- Many plant and animal species are now under threat of extinction (Table 4). Some scientists predict that if present trends in habitat destruction continue, at least 25 percent of the world's species will be lost in the next several decades.
- Such a loss of bio-diversity has profound implications for development.
- Biological resources are renewable; forests, fisheries, wildlife and crops reproduce themselves and even increase when managed properly.
- Further, the highly diverse natural ecosystems which support this wealth of species also maintain hydrological cycles, regulate climate, build soils, cycle essential nutrients, absorb and break down pollutants and provide for recreation, research and a richer quality of life.
- Marine protected areas are yet to receive the same attention as their counterparts on land. The area of sea and seabed is more than two and a half times as great as the total area of landmasses of the world but less than one percent of that marine area is currently within established protected areas. This compares with about 3 percent of the area which is protected in the terrestrial environment.
- Conservation of biological diversity under wetlands and aquatic conditions should receive greater support.
- Conserving biological diversity, therefore, is urgent because diversity provides the raw material for human communities to adapt to change.
- The loss of each additional gene, species or habitat reduces the available options.
- Loss of the biological potential of the soil, adverse changes in water availability and quality increasing biotic and abiotic stresses and the biological impoverishment of the earth are all occurring at a time when on the one hand, the human population is expanding and on the other, the pathways of economic and industrial development chosen so far have the built-in potential for climatic alterations.
The blog on Agriculture and Food Systems (Part 2) by M S Swaminathan pertains to UPSC papers GS 2 hunger and malnutrition, GS 3 Agriculture and Food security. Don’t forget to subscribe so that you never miss out on such important and interesting topics. Check out our previous blogs on various topics here.