Fertile soil and good quality water have become precious natural resources, their efficient and economical use is the first and foremost action to conserve them. The practical methods for soil and water conservation can be broadly divided into two classes.
i) Agronomic practices. ii) Mechanical measures.
By following different agronomic practices we can reduce soil erosion, increase moisture holding capacity of soil and can minimize problems like water logging, soil salinization etc.Agronomic measures for soil and water conservation
1. CONTOUR- FARMING: As rain falls, a lot of runoff is generated which generally leads to soils erosion on its way downward. This removes the top fertile soil along with soil nutrients and plant seeds thus leading to scanty and uneven growth of crop. 2. MULCHING: Mulching is one of the simplest and beneficial practices for soil and water conservation. Mulch is simply a protective layer of material that is spread on top of the soil to prevent it from blowing and being washed away. Mulch can either be organic such as grass clippings, straw, bark and similar materials or inorganic such as stones, brick chips and plastic. . The mulching practice yields following benefits:i) Protects the soil from erosion. ii) Conserve moisture in soil thus saving the need for frequent irrigation. iii) Reduce compaction of soil due to impact of heavy rains. iv) Maintains soil temperature. v) Prevents weed growth and loss of soil nutrients.
3. ENHANCING THE GROWTH OF SPECIFIC CROPS: Enhancing the growth of specific crops which provide maximum cover, reduce runoff and soil loss e.g. legume crops in general provide a better cover and hence better protection to cultivated land against erosion. These may vary from region to region depending upon topographical and climate conditions. 4. STRIP CROPPING: It is a combination of contouring and crop rotation in which alternate strips of row crops and soil conserving crops are grown either at right angles to the direction of the prevailing wind, or following the natural contours of the terrain to prevent soil erosion. 5. MIXED CROPPING: In this practice two or more crops are grown in the same field at a particular time. Some of the benefits of mixed cropping are better and continuous cover of the land, good protection against the beating action of rain. The different crops grown in mixed cropping have their roots at different depths holding the soil more firmly thus preventing soil erosion.Mechanical measures for soil and water conservation
These measures play an important role in soil and water conservation. These are used in conjugation with agronomic practices when they alone are not much effective. The main principles of mechanical measures are:(i) To facilitate infiltration by increasing the time of concentration. (ii) To breakup a long slope into several short ones to decrease velocity of runoff.
1. CONTOUR-BUNDING: In this practice small bunds are constructed at regular intervals across the slope of the land. 2. SUBSOILING: It is basically a primary tillage operation, which consists of breaking the soil structure up to a depth of 30 to 60 cm. This practice facilitates greater infiltration rates and moisture holding capacity of the soil. 3. BASIN LISTING: In this method of soil and water conservation, basins are constructed using a special implement called basin-lister. These basins are constructed across the slope. Basin listing provides maximum time to rain water for infiltration into the soil. 4. BENCH TERRACING: In this practice a series of platforms are constructed having suitable vertical drops. The range of vertical drop may vary from 2 to 6 feet depending upon prevailing conditions. The capital cost of bench- terracing is more than that of bunding initially but in longer run it proves economical.Hannah Krujia SMS – Agronomy KVK, Phek Dist.