Soil
Management for sustainable agriculture
Introduction
With the
current foodgrain production standing at abut 200 million tonnes, India needs to produce
an additional 5-6 million tonnes of foodgrains annually in the next decade to meet the
requirement of an estimated population of nearly 1120 million in 2010 AD. This high
population also necessitates significant increase in the production of other agricultural
products like oilseeds, cotton, animal products, fruits, vegetables etc. The added problem
is that, now we will have to produce more food and other agricultural commodities under
conditions of diminishing per capita arable land and irrigation water resources and
expanding biotic and abiotic stresses.
Commercialisation
of agriculture in response to domestic and world market changes will induce drastic shifts
in cropping patterns and resource use. Nearly all agricultural production of the future
must come from productivity of the soil, which is now mostly sick and substandard.
Sustainability
is defined as "the successful management of resources to satisfy changing human needs
while maintaining or enhancing the quality resources". It is measured as the ratio of
output to input taking into account stock depletion.
Soil Management
Land,
water, climate, flora and fauna are the basic natural resources for agricultural
development, which are subject to various kinds of deteriorating influences. Production of
more food require new agricultural technologies and management system and providing
increased productivity per unit of plant, water, energy, labour and investment by suitable
location, specific crop production technology, tillage operations, seeding, weed control,
water and fertilizers application and crop management. Because of continuous cultivation
over centuries and intensification of agriculture in recent years, there has been
progressive and substantial depletion of the soil reserves. Of late, secondary and
micronutrient deficiencies are also emerging and the crop response to these nutrients is
increasing. The factors responsible for higher yield are high soil productivity, supply of
balance crop nutrients are the most important. Soil productivity is based on the mineral
composition and structure of the soil, depth and drainage facilities, organic matter,
intensity of earthworm and microbial activities. Fairly well productive soil in
combination with assured irrigation and optimum supply of nutrients can enhance the crop
yields by 200-300%. Despite increasing use of chemical fertilizers over the years, there
has been continuos nutrient mining of the soils. The nutrient remove from the soil for
production of foodgrains and other agricultural crops far exceeds the nutrient applied.
The threat to long term sustainability of agricultural is not due to alleged excessing use
but primarily due to under use of fertilizer and the resultant nutrient mining of the
soils. This is necessary for maintaining soil and ensuring sustainable agriculture.
Management Practices
Soil
productivity can be enhanced through following practices:
Nutrient
supplying power of soils, crop responses to added nutrient and amendment needs can safely
be assets through soil testing choosing of right targets and application for appropriate
amounts of nutrient, help to sustained soil fertility and crop yields.
Soil and
water conservation
To avoid
loss of productive soil, agronomical and mechanical measures namely contour bunding, strip
cropping, establishment of live hedges, mulching etc. should be followed.
Use of
organic manure and bio-fertilizers
To
maintain or to improved soil fertility physical and chemical properties of soil and
increased water holding capacity of soil use of organic manures viz. FYM compost, vermi
compost, rural agricultural waste, tank silt application will help to built the soil
organic matter base as a reliable index of fertility. Earthworms occuring in the soil are
an indicator of the agro eco-systems health for stable aggregation of clay organic
matter complexes and efficient nutrient recycling.
Improving
physical condition of soil
Physical
constraints affecting productivity and cultivation practices e.g. hard pans can be
corrected by breaking (deep tillage), compaction for excessively permeable soils,
preventing crust formation by organic mulching.
For
favorable crop production salt affected soils can be improved by adding soil amendments
viz. Acidic soils- Liming, Alkaline soils- Gypsum, sulphur, pyrites and adding soil
conditioners e.g. crop residues, manures and other organic substances.
Increasing
use of secondary and micro nutrients
Application
of major nutrients through chemical fertilizers has a direct influence on crop yields,
also crops shows secondary and micro nutrient deficiencies and crop response to these
nutrients hence attention has to be paid to increasing use of these nutrients which have
appeared as major limiting factor. |
Ag.
Technologies
(Soil Magt.)
|