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

摘要

Bah land (rain-fed upland bench or sloping terraces) in Nepal is increasingly becoming a focus of concern in terms of soil fertility decline and management. Understanding the circumstances leading to high erosion and leaching losses, and the areas particularly affected by high losses, are essential prerequisites for attempting to improve soil conservation. Participatory research was conducted with farmers in three contrasting agroecological regions: Nayatola (20-25 slope, 1000-1500 mm annual rainfall); Landruk (bench terraces 0-5 slope, 3000-3500 mm annual rainfall); and Bandipur (bench terraces 0-5 slope, 1100-1500 mm annual rainfall). The research aimed to develop soil and water management interventions that control erosion without resulting in high leaching and so are effective in minimising total nutrient losses. Interventions tested include the control of water movement through diversion of run on, planting fodder trees and grasses on terrace risers on bench terraces in high rainfall areas, and strip cropping in non-terraced sloping fields of low to medium rainfall areas. The interventions were effective in reducing soil loss from ban in comparison with existing farmer practices, but no effect was observed on nutrient losses in solution through runoff and leaching.