More then eighty five percents of land areas in North Vietnam are considered as sloping land. Current production practices cause soil loss and destruction as the soils are deeply weathered, poor in nutrient, and highly vulnerable to erosion.
From 1999 to 2002 a participatory watershed research and application was carried out in Thanh Ha farm, Kim Boi district, Hoa Binh province. The main aim of the research was firstly to introduce improved soil, water and nutrient management technologies and secondly to evaluate suitable cropping systems for efficient use of natural resources. The approach we have taken was to ensure maximum participation of farmers in planning and execution of all activities. Various measures for the movement of water, soil, and nutrition have been undertaken. As a result, we found that there was about 25-30 cm increase in the groundwater level in the benchmark watershed wells compared to those outside the watershed. In addition application of polyethylene mulch resulted in doubling the groundnut yield. Application of the improved practice has resulted in increasing of 8% in yield of maize with the reduction of 28% in using nitrogen fertilizer. Large scale on-farm demonstrations were conducted with improved varieties of soybean, groundnut and watermelon. Farmers were highly impressed with the legumes crop and showed interest in planting the crops in large scale plantation with more than 50% of the total land area.
Thus, watershed based integrated natural resources management technologies has offered opportunities for crop diversification, improving soil health and ground water and reducing the soil erosion and land degradation in major sloping land of northern Vietnam.