Wednesday, May 21, 2008

Can Sustainable Agriculture feed the Population !

With the introduction of green revolution technologies, the food grain production has gone up manifold. Modern, high yielding varieties supported by technologies such as fertilizers, pesticides, mechanization, irrigation, etc have contributed to the magnificent increase in the production. Many developing countries like India have become self sufficient in food production.

On the flip side, modern farming has affected ecology and led to degradation of natural resources particularly soil and water. Moreover, under fragile ecosystem, the crop production is becoming stagnant and showing the signs of decline. The additional technological introduction is not contributing to any further increase in the production and a point of diminishing marginal returns is looming large over production front in agriculture.

Due to degrading environment and natural resources, no modern technology can assure indefinite increase in production. But the population is growing at an alarming rate, which is the potential cause for food crisis in the future.

In this backdrop, sustainable agriculture is considered a new road ahead by development visionaries. The agricultural community has no dispute over the idealness of the sustainable practices. But the real issue is about production potential to meet the food demand. No doubt that sustainable practices cannot yield to the same measure as modern practices in the initial stages of farming, but over the years, it can ensure similar and stable yields.

What are the key aspects to make it successful !

Eating junk food : We are eating more because we eat junk food. Modern practices have been harping on production in terms of quantity but not quality. Various researches have conclusively proved beyond doubt that food produced under sustainable or organic farming are better in nutritional quality. It has direct bearing on consumption. For example, farmers themselves have experienced that some traditional varieties of rice and finger millet can cook well and the quantity of grain or floor required for a family is 30-35% less compared to modern varieties under chemical farming. This is due to rich mineral content in those grains. Traditional varieties, evolved over thousands of years, under a particular agro climatic condition, adapt well and produce superior quality grains than the externally introduced ones. The milk of local animal breeds has more fat and proteins than the exotics. Sustainable agricultural practices produce better quality produce than the modern practices. Traditional or indigenous varieties adapt and produce better quality produce. Therefore, identification and introduction of superior local genetic resources in breeding process is an important scientific approach in sustainable agriculture to meet food demand in the changed scenario.

Post harvest management : The losses in transit, storage and distribution are too significant to ignore. Food Corporation of India has recorded 25-30% loss of food grains in storages, quite often. Sustainable agriculture can achieve a yield of 75-80% under conventional agriculture within a reasonable period of 2-3 years. Streamlining of post-harvest operations and minimizing the losses is a very important strategy to meet the food demand under sustainable agriculture. Creating decentralized infrastructure and distribution can have great impact on post-harvest management and reducing the losses.

Eco-friendly practices : Innovative practices have proved successful in obtaining yields comparable in some cases and much higher in some others. SRI (system of rice intensification) in rice, for example, with 30-40% less water consumption using semi-aerated soil condition can give additional yield of 50%, on an average. Similarly, mulching and other in-situ moisture conservation practices can improve yield under sustainable practices particularly under rain fed farming.

Food and crop diversity : Mono cropping, as a natural consequence of modern agriculture, tends to erode diversity in food and cropping systems. Out of known 4500 crop species in the world, hardly 20 are adding to 90% of our food requirement. Again, few varieties in each crop account for more than 90% of the production. Diversified food, due to rich nutritional value, has great potential to reduce consumption. Reinventing multi-cropping and species diversity in farming systems is central to sustainable agriculture.

Land diversion : Considerable land is being diverted every year through policies of the state. In 1970’s, large area under food grains was diverted to silkworm rearing in south India by establishing silk industry and motivating the farmers. Similarly, cotton is being promoted on large scale to boost export economy. Urbanization and industrial development policies are diverting areas under food grains and horticulture. This has to stop somewhere to ensure food production for the growing population. Increasing pressure on land through reducing the cultivable area pushes us to chemical and intensive farming, which is not ecologically sustainable.

Sustainable marketing : Promoting decentralized, local marketing processes gives stability to agricultural production. Cropping system determined by an agro climatic situation has to dictate agricultural market. This stabilizes the demand-supply chain. This, in turn, scales down unorganized production by the farmers dictated by fluctuating distant market, which is also a source of post harvest losses. Sustainable marketing and sustainable farming always go together.

Agro eco system : Reviving agro ecology is the sure way of increasing productivity and sustaining it. It enriches the soil through biomass, conserves other natural resources (water, insect and microbial environments) and creates microclimate. It creates pivotal role in recycling of nutrients to sustain soil productivity thus contributing to production.

Development policies : Achieving food production through sustainable practices needs teeth to state policies. Balancing export and domestic economies, putting a lid to urbanization and diversion of land, post harvest management and distribution, interventions in institutional research, etc can make it happen. Phase wise transition to sustainable agriculture and a meticulous plan for the future can take it forward.

Saturday, May 3, 2008

Eco-friendly Soil Nutrient Management

When the first fertilizer was manufactured in the 19th century, scientific community was euphoric that it would be the panacea for all the ills plaguing agriculture in the world. Undoubtedly, synthetic nutrient sources have led to huge increase in production of crops particularly on low fertile soils with high yielding varieties and hybrids. Fertilizers result in rapid growth and development of plants when applied particularly under irrigated conditions.

The euphoria was short lived. Soon, we could notice the grave dangers of synthetic fertilizers on the health of the soil, quality of underground water, microbial ecology, tolerance of crops to pests and diseases, etc. Over the years, synthetic fertilizers make the soil biologically inert resulting in poor soil structure and dominance of soil borne pathogens. Fertilized soils degrade in water holding capacity due to depletion of beneficial soil microbes and biomass content. Fertilized crops are susceptible to pests and diseases due to lush growth, which necessitates heavy pesticide applications. Synthetic pesticides destroy the dynamic equation between insect pests/pathogens and beneficial insects/microbes. The cost of production increases in the inorganic farming practices due to degradation of ecology. The farming practice heavily dependent on external, synthetic sources and poisonous pesticides is not ecologically sustainable. The food thus produced is unhealthy due to accumulated toxic substances in the food chain. Synthetic fertilizers are the key factor in this vicious cycle of unsustainable farming.

Are there alternatives!
Alternative soil nutrient management could be the turning point in reversing these unhealthy farming systems. Adding organic carbon and biomass is the effective way out. Scientific community world over has accepted the un-sustainability of inorganic sources for soil and crop management. But, it has been pondering over the alternative sources, as the manures and biomass are bulky and low in nutrients. The quantity required to meet the nutrient demand is exorbitantly high compared to concentrated inorganic fertilizers.

The concentrated organic manures such as edible and non-edible oil cakes contain high nutrients but are uneconomical on the farmers’ field. Among the bulky manures, horse manure, pig manure, night soil, sludge and chicken manure are quite high in nutrients. Chicken manure is widely available and most economical also. It contains 3% nitrogen, 2.5% P2O5 and 1.5% K2O besides being rich in secondary and micronutrients.

The comparison between chicken manure and synthetic fertilizers throws some interesting facts. 1000kg chicken manure supplies 30kg N, 25kg P2O5 and 15kg K2O. To supply this through fertilizers, farmer has to apply 52kg DAP, 45kg Urea and 25kg MOP. Under the local conditions, the cost of chicken manure would be RS. 600-700 per 1000kg. The costs of fertilizers would be about Rs. 900-950 for the above quantity. To supply micronutrients corresponding to chicken manure, it would cost much higher with fertilizers as micronutrient fertilizers are to be added separately. In short, a farmer has to spend Rs. 10 per kg of N, P2O5 and K2O together through chicken manure while Rs. 13 through NPK fertilizers. It clearly demonstrates that, there are organic sources, which are cost effective, ecologically sustainable and practical.

Chicken manure is available in the country in large quantities as poultry is a huge meat industry. Other such widely available sources are sludge, pig manure and fishmeal. They are potential sources of nutrients to the soil as alternatives to chemical fertilizers.

Environmental pollution
The utilization of these sources also helps in combating environmental pollution as they are dumped as wastes or diverted as in case of sludge. Based on local conditions, such organic wastes can be recycled for soil nutrient management. In most developing countries, these wastes are the sources of ground water contamination and human diseases.

Policy directions
State policies in this direction can create conducive atmosphere to utilize such organic wastes in sustainable agriculture. Establishing small-scale industries to recycle the wastes and subsidies through departments to promote their applications can be of great impact on the ground situation in farming systems. It is well known that fertilizers are popular more due to government patronage through subsidies and fertilizer industries than due to farmers’ preference as such.