Agricultural wastes are those that are left in the farm after harvest of final products. It is also called as Biomass waste. These include harvest trashes, weeds, wastes obtained from livestock, poultry, slaughter house and also agroindustrial wastes. In recent years the improper disposal of agricultural wastes are increasing day by day.
Conventional agriculture was based on using the farm obtained resources like harvest trashes, weeds, cowdung etc as manure in the field. But post green revolution, farmers are entirely dependent on chemical fertilizers for meeting the nutrient requirements of the crops. Though chemical fertilizers help to obtain higher yield , continuous usage of these for 10 to 15 years in the same land can make the Crop susceptible to the existing environmental condition, reduction in soil health due to decrease in number of beneficial microorganisms in the soil, biomagnification of residual fertilizers in the soil, reduction in yields economic and environmental health in the long term thereby abetting suicides.
FATE OF AGRICULTURAL WASTE AT PRESENT
The most common practice followed is the burning of agricultural residue in situ or dumping of the residue. Such practices helps in clearing the land for cultivation for the next crop easily. This practice is highly adopted as it reduces space, time and pocket friendly for poverty ridden farmers. Even though there are many technological interventions for converting agricultural waste into a valuable resource, farmers are reluctant to implement it as it requires high investment in the form of buying or hiring equipment and tractor, fuel cost, labor and transportation costs.
The foremost effect of burning is the emission of particulate matter which leads to air pollution. And the next effect is barrening of land and reduction in soil fertility. Instead of using farm saved organic materials, farmers depend on chemical fertilizers, hence cost of cultivation also increases. The nutrients present in these organic waste ultimately goes off without any use.
WAYS AND MEANS TO MAKE WEALTH OUT OF WASTE
There are many ways to make better use of this wastes and obtain other useful resources.
The first option is to opt for incorporation of the residue as a mulch, which will enhance the soil quality and crop yield. Though this method is beneficial, farmers are not switching, owing to its’ high investment and annual maintenance costs for equipment and machineries such as Turbo Happy Seeder and Super Straw Management system.
Second way is to go for Composting. Organic wastes such as leaves, stalks, poultry wastes, livestock wastes, slaughterhouse wastes etc composted. Composting can be done near the farm itself and the compost can be used as manure for crops as well as a soil conditioner. The compost is rich in both primary nutrients – Nitrogen, Phosphorus and Potassium (N P K) content and in micronutrients such as Mn, Cu, Fe, Zn etc. thus retaining the soil fertility and reducing the dependence on chemical fertilizers.
Third, Large farmers can go for PELLETING of organic wastes. Pellets should contain 4% to 5% water content. Pellets can also be used as a alternate form of energy. Other advantages of these pellets include higher biomass, less space, higher energy, and easy to handle. High cost of briquetting machines is the only disadvantage here.
Finally, the oldest and mostly practiced method is production of BIOGAS from organic wastes such as animal dung, poultry and plant wastes. It is highly useful for farmers with livestock. 2m3 of biogas is sufficient for a family containing 5 members. The slurry obtained after obtaining biogas can also be used as a soil conditioner.
The benefits of such waste management practices are manifold as it is a sustainable solution. These measures are eco-friendly as it maintains soil fertility, promotes higher resource efficiency, reduces air pollution and provides resistance to crops. In economic perspective, it reduces the crop failure and can save farmers from financial crisis. In a social view point, increased harvest and assured harvest in long term will substantially improve farmers’ standard of living.
Though various methods are available, awareness among farmers are poor about usage of these scientific techniques for efficient resource utilisation. Subsidies to convert farm waste to wealth is a viable option. Besides, Research should focus on low cost, high efficient methods and tools for wide scale adaptation.
Author, Supriya. M is a B.Sc (Agriculture) student of Imayam Institute of Agriculture and Technology (IIAT), Tamilnadu Agricultural University (TNAU). Under the Guidance of Dr.B.GUNA, Assistant Professor (Agricultural Extension), IIAT.