||Broad objectives of watershed development
||Principles or objectives of watershed management
||Components of watershed development
||Significant Gains From watershed Development
Definition of watershed :
- Watershed is an area above a given drainage point on a stream that contributes water to the flow at that point.
- Watershed is a natural unit draining runoff water of common point of outlet.
- The watershed is geohydrological unit or a piece of land that drains at common point. Catchments basin or drainage basin are synonymous of watershed.
Broad objectives of watershed development
In general the watershed development fulfills the following objectives.
- To bring about increased productivity.
- To make yields less subject to the effect of erratic rains.
- To improve resource conservation ( soil & water ) and land use .
- to create additional employment potential for the small/ marginal farmers and agricultural labourers.
Principles or objectives of watershed management
- Utilizing the land according to its capability.
- Putting adequate vegetal cover on the soil during the rainy season.
- Conserving as much water as possible at the place where it falls. i.e. in situ conservation of rain water .
- Draining out excess water with a safe velocity and diverting it to storage ponds avoiding hazards situation and store it for further sue for supplemental irrigation during stress periods.
- Avoiding gully formation and putting checks at suitable intervals to control soil erosion and recharge ground water.
- Maximizing productivity per unit area, per unit time and per unit of water.
- Increasing cropping intensity and land equivalent ratio through intercropping and sequence cropping.
- Safe utilization of marginal lands through alternate land use system such as horticulture , Agro forestry, silvipasture etc.
- Ensuring sustainability of the eco – system benefiting the man – animal – animal - plant – land, water animal - animal plant – land, water complex in the water complex in the watershed.
- Maximum and combined income from the inter related and dynamic crop – livestock – tree – labour complex over years.
- Stabilizing total income and cut down risks during aberrant water situation.
- Improving infrastructure facilities with regards to storage , transportation and marketing
- Improving the socio – economic status of the farmers.
Components of watershed development
Following are the general items of watershed development which are required to be executed in the catchments area depending upon the prevailing situation.
1. Soil and land management
- Interceptor drains.
- Graded bunding
- Bench terracing
- Interbund vegetative barriers
- Grass waterways.
- Improvement of ill drained soils
- Nala draining / improvement.
2. Water Harvesting structures:
- Nala bunding
- Farm ponds
- Percolation tanks
- Minor irrigation tanks
- Stop dame in nalas
- Underground diaphragms.
3. Afforestation cum pasture development for rural energy and forage for animals:
- On private marginal and culturable waste lands.
- On community and government forest lands.
4. Agricultural development
- Selection of crops and their varieties suitable for local soil and climatic situation.
- Adoption of appropriate cropping system.
- Contour farming .
- Strip cropping.
- Mulching and crop residue management.
- Adoption of alternate land use system depending on land capability such as Alley Cropping, Agro- horticulture, silvipastural management, dry land horticulture, tree farming, and pasture management.
Significant Gains From watershed Development
- Soil and moisture conservation: Soil and moisture conservation is the basic need in rained agriculture. Top soil is the most fertile part of the soil profile. This layer is lost due to erosion causing decrease in yield agronomic and mechanical measures for soil and moisture conservation are adopted in the watershed such as contour farming, strip cropping , mixed cropping , inter cropping contour/ graded bunding , vegetative barriers etc.
- Increase in water storage: Due to construction of surface water storage structures like minor irrigation tanks, percolation tanks, nala bunds, farm ponds etc. The excess runoff water is collected in these storage structures which in turn is used either for supplement irrigation for field crops , horticultural crops or for drinking water to animals . Thus, additional area can be brought under irrigation.
- Increase in number of wells: Due to considerable improvement in ground water Recharge, the numbers of dugout well or tube wells are increased . The farmer can apply protective irrigation to various field crops whenever necessary . Thus the area under well irrigation is increased.
- Increase in cropping intensity: Due to increase in water resources and adoption of appropriate crop management practices, and area under double cropping is increased, which results in increasing cropping intensity.
- Increase in fertilizer use: Due to increase in water potential and moisture conservation measures , the fertilizer use by the farmers is increased.
- Improvement in crop production and productivity: Adoption of vegetative and mechanical conservator measures, results in considerable reduction in soil, water and nutrient losses from the watershed area. Further adoption of improved crop management practices results in appreciable increase in crop productivity and total crop production from these areas.
- Animal and milk production: Appropriate management of marginal land with productive grasses and pastures, the total forage resources are increased which reflect in increasing animals component resulting increase in meat milk production.
- Increase in afforestation and alternate land use : For producing fuel, fodder and timber, alternate land use programme is implemented in watersheds. Dry land horticultural species in addition to fuel and fodder tree species have shown promise in the watersheds.