Nutrient Management Strategies for Poverty Alleviation in Tibet

This soil fertility study project is part of the Canadian International Development Agency (CIDA)-sponsored alleviating poverty project. The aim is to develop and transfer soil management knowledge and practices that improve crop productivity and farmer income while protecting the environment by reducing soil, water, and nutrient loss from the landscape. Soil samples were taken from the project areas in Zhanang County and analyzed for available soil nutrient status. Soil test-based field trials and demonstrations were conducted on winter wheat and highland barley in 2002. Training courses for local technicians and farmers were also organized.

Results show that the soil nutrient limiting factors are nitrogen (N), potassium (K), magnesium (Mg), sulfur (S), manganese (Mn), and zinc (Zn). Compared to common farmer fertilization practice which ignores K, balanced fertilization with 150-75-72 kg N-P₂O₅-K₂O/ha increased highland barley yield by 2,330 kg/ha (65%) in Jielin Village, and by 1,870 kg/ha (55%) in Namsailing Village. Net income was US$390 and US$320/ha higher than common farmer practice in Jielin and Namsailing Villages, respectively. Compared to farmer fertilization in wheat, the same fertilizer recommendations significantly increased yield by 914 kg/ha (25%), and net income by US$149/ha.

Data indicate that under the current circumstances, wherein secondary and micronutrient fertilizers are not available in the Tibetan fertilizer market, balanced fertilization with N, P, and K is highly recommended. Since these soils are relatively sufficient in P, application rates of P should be adjusted in order to increase K use. Combined application of chemical fertilizers and manure is encouraged wherever these organic sources are available. This technology is ready to be transferred within the area surrounding the initial project sites. Tibet-02 NMS PA