Describe sustainable agriculture
What will be an ideal response?
ANS:Increasing
concern for long-term farm productivity and the effect of agricultural practices on the
environment led to the concept of sustainable agriculture. In 1989, the American Society of Agronomy
declared that "a sustainable agriculture is one that, over the long-term, enhances environmental quality
and the resource base on which agriculture depends; provides for basic human food and fiber needs; is
economically viable; and enhances the quality of life for farmers and society as a whole."
Those who research or practice sustainable agriculture are concerned that agriculture's resource base is
being depleted: declining soil productivity due to erosion and loss of organic matter and nutrients;
depletion of fertilizer sources like phosphate rock; and cost and availability of energy. A feared
consequence of large-scale agriculture is a degraded environment: pollution of water by agricultural
chemicals, nutrients, and siltation of waterways. Stability of the farm economy and community further
motivates sustainable agriculture.
Sustainable agriculture is a philosophy and collection of practices that seek to protect resources while
ensuring adequate productivity. It strives to minimize off-farm inputs like fertilizers and pesticides and
to maximize on-farm resources like nitrogen fixation by legumes. Top yields are less a goal than
profitable yields based on reduced input costs. Soil and water management are central components of
sustainable agriculture. Techniques include crop rotation, conservation tillage, cover cropping, nutrient
management, and others.
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