Soil
Management in Water Stress Condition
Having
finer differences between dryland and rainfed lands, it is clear that both suffer due to
moisture stress or water stress. The core problem of dryland is the scarcity of water as
per the requirements of the crop and soil. Therefore to conserve maximum amount of
moisture in the soil from low and untimely rainfall which causes abberent weather
conditions. Hence emphasis should be given on the productions of reasonable crop yields on
economic and sustained basis. As water is most important in scarcity areas, conservation
of soil and water are taken which is inter related and where one is tried the other is
also achieved.
Management of soil
Tillage
Tillage
practice conserve the basic resources of soil and water also aim at complementing soil and
water conservation measures such as graded bunds and land levelling. All tillage
operations should be carried out at optimum soil moisture conditions when the resistance
to tillage tools is low, resulting in lower draft and power requirements and better soil
tilth. The ploughing of deep soils should be done once in 3-4 years. In case of light,
shallow and medium soils instead of ploughing frequent hoeing should be done to receive
and retain moisture.
Mulching
To conserve
soil moisture, temperature control, prevention of crust formation, reduction in runoff and
erosion, to improve soil structure mulching is done. Using mulches particularly organic
mulches e.g. jowar or bajara stubbles, paddy straw or husk, sawdust @ 5 tonnes per ha.
Crops
To reduce
the loss of moisture received by the soil and soil losses through erosion,early maturing
adaptable crop varieties with deep and ramified root system and having a dense canopy
should be grown e.g. cereal - legumes or strip cropping or erosion permitting and erosion
resisting crops.
Incorporation of organic matter
To improved physical properties of soils,water-holding capacity and to build up the soil
fertility a liberal quantity of organic matter, incorporated in combination with green
manure, crop residues with inorganic fertilizers.
Mechanical Practices
Dryland soils are
subject to serious erosion problems. Following measures are taken which includes the break
up of slopes,intercept run off ,give more time of infiltration and divert water into
channels.
Contour bunding
To retain
soil from erosion and rainwater from run off ,the bund section is 1.61 m2 in
vertisols and 1.05 m2 in Alfisols, vertical distance 0.9 m can be used across
the slope of the land on a level that is along the contour.
Graded bunding
Graded
bunds are of 0.8 m2 cross section in vertisols and 0.5 m2 in
Alfisols. The area lost should not be more than 3-5% and there would be no water
stagnation. Graded bunds with grassed water ways and box type masonry drainage and outlets
in arable lands. Formation of percolation tanks which leads to water in due course, find
its way into subsoil and recharges the ground water.
Tie-ridging
The
practice of tie ridging, where adjacent ridges are joined at regular interval by barriers
of ties of the same height, allows the water to infiltrate and prevent run-off except
during intense storms.
According to soil
types
In red
soils, graded bunds are preferred the contour bunds because of scope for harvesting run
off water for supplementary irrigation. In black soils with their low infiltration
characteristic, cultivated fields suffer from the problem of water stagnation,runoff
losses can be reduced by adopting the graded bunds. Besides bunding, creating corrugations
across the slope as the run off water flows along these corrugations at a safe and
non-erosive velocity.
Other technologies
Growing a shelter belt or forage, fuel and timber trees of protect the land from wind
erosion. Adopting water harvesting by inter-plot, inter-row, modified inter-row, broad-bed
and furrows system for in situ conservation. Thus to utilize available moisture and
water for satisfactory growth of crops, both soil management and water management measures
are taken in water stress areas as soils are subject to erosion and loss of available
moisture.
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Ag.
Technologies
(Soil Magt.)
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