Watershed management harmonizes the use of soil, water, and vegetation in the watershed area to increase agricultural productivity and conserve natural resources. Conservation measures include revegetating barren land to assist in the control of runoff; introducing sustainable agricultural practices for hilly areas to improve soil and water management; and constructing water reservoirs for irrigation. Watershed management often requires collective action among diverse stakeholders, among whom costs and benefits may be distributed unevenly. Accordingly, watershed investments must rely on people with the experience, incentives, and skills to organize stakeholders. Complementary investments may be needed to improve access to agricultural inputs and services (seedlings, veterinary services, land titling, and so forth) and output markets (processing facilities, roads). Rainfed agriculture in much of the world is characterized by low yields, low and declining soil fertility, severe soil erosion, and low investment in land improvement. Soil and water conservation efforts have treated these problems in a piecemeal manner and have failed to capture synergies among various components of a watershed system. As a result, development efforts are often threatened by deteriorating environmental conditions in the watershed area, due in part to inappropriate resource use and increasing population pressures. Key Investments in Watershed Management Watershed management seeks to make the best use of soil, water, and vegetation within the constraints of a watershed’s agroclimatic and topographic conditions to strengthen the natural resource base (soil, vegetation cover) and to increase agriculture productivity, thereby improving peoples’ livelihoods. Watershed management strategies vary. For example, in dry areas, increasing water availability raises potential returns, making the land more attractive to investment; in areas with short, intense rainy seasons, watershed management harvests water in surface reservoirs; and in areas with excess moisture, facilitating safe runoff through contour plowing or drainage systems reduces waterlogging and erosion. New modeling tools coupled with more precise spatial and temporal impacts of land cover and land-use changes on water flows are providing new information to guide managers and policy makers (box 5.12). Investments in technology, social institutions, and markets are frequently needed to maximize the impact of improved watershed management. Technical investments. Soil conservation, water harvesting, increasing vegetative cover, and safe disposal of excess water are basic watershed management technologies. In dry areas the focus is on water harvesting (capturing rainfall otherwise lost to runoff), whereas in wet areas it is disposal of excess water. In many upland watersheds in seasonally water-scarce areas, upper catchments are often degraded lands used for grazing, gathering firewood, or cultivation (often on unproductive plots). Lower watershed areas typically contain better agricultural land. Harvesting water from the upper catchment areas makes it available for irrigation and other uses downstream.     
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