摘要
Soil erosion has resulted in removal of the topsoils containing fine soil particles and plant nutrients, causing decrease in soil fertility in the Hindu Kush, Karakoram and Himalaya(HKH) region. The existing production of cereal crop grains has been reduced to one third of the potential crop grains production owing to land degradation and poor farming practices. It is necessary to assess risk of soil loss and identify appropriate controlling measures to address issues of low agriculture productivity and water insecurity in the region. In the present study, severity of soil loss was predicted using Revised Universal Loss Equation(RUSLE) and ecological measures were identified for sustainable mountain agriculture in the HKH region of Upper Indus Basin, Pakistan. Overall 62.6% area was found to have very low risk of soil loss, i.e., <5 t/(ha·yr), 15.8% area low risk, i.e., 5-25 t/(ha·yr) and 7.5% area moderate risk, i.e., 25-50 t/(ha·yr) in the region. The risk was high, i.e., 50-100 t/(ha·yr) and very high, i.e., >100 t/(ha·yr) in about 6.8% and 7.4% areas respectively. The mean rate of soil loss was about 41.9 t/(ha·yr) in the Hindu Kush, 31.1 t/(ha·yr) in the Himalayas, 18.8 t/(ha·yr) in the Karakoram and overall 29.7 t/(ha·yr) in the three HKH ranges. As such no considerable measures have been adopted by the communities for restoration of the degraded areas except raising fruit/farm trees and supporting limited social forestry for their livelihoods. The slopes cleared for cultivation and susceptible to erosion may be stabilized through sowing/planting of multi-purpose plant species and formation of proper bench terraces. The conservation of forest ecosystem and pastures at higher elevations would help in reducing overland water flow, risk of flash flood hazard and minimizing sediment loads in the downstream. It is essential to adopt site-specific resource conservation techniques and restore possible ecosystem health for sustainable agriculture and economic development in the region in future.
基金
project support by Ministry of National Food Security and Research, Islamabad for this study is highly appreciated。
