| 1 | Impacts of land uses on runoff and soil erosion A case study in Hilkot watershed Pakistan显示文摘In certain areas of the Hindu Kush-Himalayas(HKH),ecological situation is depleting day by day and approaching to the point of no return through gradual environmental degradation.Surface soil erosion from most of the areas is a serious threat to sustainable agriculture and sediment accumulation in down stream reservoirs.An extensive study in the Hilkot watershed,a catchment of Terbala Dam, was started by the People and Resource Dynamics Project in 1998.Main objectives of this study were to calculate annual runoff and soil losses from different land uses and compare their seasonal distribution at plot level.Four experimental plots based on land use classification(i.e.degraded, forests,agricultural,and pasture lands)were established.Area falls in the monsoon region,about 38% rainfall occurred in the monsoon period(July to September),while in the pre-monsoon(March to June)and the winter period(October to February)received 35%and 27%of the total rainfall, respectively.The annual rainfall in the watershed was 1160 mm.The runoff and soil loss pattern varied among different land use types.In all the erosion plots,almost 50%of the runoff and soil loss occurred during the monsoon period and was negligible during winter.The mean maximum runoff was from the degraded plot(674 m^3/ha/y),while minimum was observed from the pasture plot(310 m^3/ha/y).Average runoffs on other land uses were 529 and 460 m^3/ha/y,from the forest and agriculture plots,respectively.Annual soil loss from all land uses ranged between 0.3 to 16.3 t/ha. Average maximum soil loss was recorded from the degraded plot(6.5 t/ha/y)and average minimum (1.8 t/ha/y)was on the pasture plot.Similarly,average soil from other plots was 3.3 and 3.4 t/ha/y, measured from the forest and agricultural plots,respectively. | ZOKAIB S. NASER Gh. | 2011 | International Journal of Sediment Research2011，26，3： | 4 |
| 2 | A study on rainfall,runoff,and soil loss relations at different landuses-A case in Hilkot watershed in Pakistan显示文摘Reliable field data for all hydrologic parameters are often unavailable for watersheds even for those intensively monitored.In the absence of reliable such data,verified mathematical relations for an area can be used for other areas with same hydrologic and climatic regimes.The objectives of this research were:1) to assess the total runoff and sediment loss,and 2) to develop rainfall,runoff and soil loss relations for four prominent landuses(including degraded,pasture,forest and agriculture lands) in the Hilkot watershed(Pakistan).Four experimental natural runoff plots were established on the landuses (degraded,pasture,forest and agriculture land).The field study and data collection were conducted in the Hilkot watershed from 1999 to 2005.Regression analysis was conducted to establish relations among rainfall,runoff and soil loss for all landuses using.Regression analysis indicated good correlation with field data. | ZOKAIB S. NASER Gh. | 2012 | International Journal of Sediment Research2012，27，3： | 2 |
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