|
|
|
| Hydrological Response Model On Soil and Water Conservation in Yanhe River Basin |
| Xu Xuexuan,Mu Xingmin,Wang Wei |
| Institute of Soil and Water Conservation, Northwest Sci-Tech University of Agriculture and Forestry Institute of Soil and Water Conservation Chinese Academy of Sciences And Ministry of Water Resources, 712100, Shaanxi Yangling, China |
|
|
|
|
Abstract Based on data of Yanhe river basin's hydrological stations on precipitation, runoff, soil and water conservation measure area sizes (terrace land, forestation land, grassed land, and silted dam land) from 1950s'-1980s' , the basin's monthly precipitation station weightiness indexes and the four main measure areas weightiness indexes through correlation analysis and factor analysis were built. Authors then calculated out the composed area of soil and water conservation measures and then basin' s average precipitation. Then a model based on the two new factors had been set out which is the hydrological response model on soil and water conservation. Through the model the runoff of Yanhe River responded on soil and water conservation activity had been analyzed. The result shows that the soil and water conservation activity could store more water of rainfall therefore reduce runoff. This function had been being stronger and obvious in the latest 30 years from 1950s'-1980s' . The stored water accounted for 6.48% of precipitation induced runoff amount on average of historical period. The decade averages are respectively as 0.7 % in 50s' , and 3.11% in 60s' , 8.84 % in 70s' , and 16.52% in 80s' . In 70s' of 20th century the reduction of precipitation resulted in a 12.9% down in runoff, that amount increased to 14% in 80s' . The strengthen of soil and water conservation combined with the decreased precipitation brought out further decrease in runoff of river that would be 20.6% in 70s and 28.2% in 80s' respectively comparing to runoff in 50-60s' in 20th century.
|
|
Received: 10 September 2003
|
|
|
|
|
|
|
