Interventions to Minimise Nutrient Losses from Bari Land (Rainfed Upland) in the Middle Hills of the Western Development Region of Nepal

摘要

Bari lands (rainfed upland bench or sloping terraces) in Nepal are increasingly becoming a focus of concern in terms of soil fertility decline and management. The understanding of the circumstances leading to high erosion and leaching losses, and the areas particularly affected by high losses, are essential prerequisites to attempting to improve soil conservation. Participatory research is being conducted with farmers in three contrasting agroecological regions; Nayatola (20-25° slopes, 1,000-1,500mm annual rainfall); Landruk (terraces 0-5° slope, 3,000-3,500mm annual rainfall); and Bandipur (0-5 ° slope, 1,100-1,500mm annual rainfall). The research aims to develop soil and water management interventions that control erosion without resulting in high leaching and so are effective in minimizing total nutrient losses. Interventions being tested include the control of water movement through diversion of run-on, and planting fodder trees on terrace risers on bench terraces in high rainfall areas, and strip cropping in non-terraced sloping fields of low to medium rainfall areas. Results to date indicate that the interventions are effective in reduction of soil loss from the bari land in comparison with existing farmer practice, but no effect is observed on nutrient losses in solution form through runoff and leaching.