京津水源区小流域土壤侵蚀空间模拟  

Soil erosion in a small watershed in water source areas of Beijing and Tianjin:Spatial simulation

作　　者：江青龙[1] 谢永生[1,2] 张应龙[1] 张怀 郝晓东 

机构地区：[1]西北农林科技大学资源环境学院,陕西杨凌712100 [2]中国科学院水利部水土保持研究所,陕西杨凌712100 [3]承德市水土保持科学研究所,河北承德067000

出　　处：《生态学杂志》2011年第8期1703-1711,共9页Chinese Journal of Ecology

基　　金：中国科学院知识创新重大项目(KSCX-YW-09-02;KSCX-YW-09-07);水利部公益性行业科研专项经费项目(200901051;201001036);国家科技支撑计划项目(2011BAD31B01)资助

摘　　要：针对京津水源区生态环境脆弱、水土流失空间分异大、突发性强等问题,以河北省平泉县东北沟典型小流域为例,采用GIS技术与CSLE模型对其土壤侵蚀进行二维空间模拟及侵蚀规律研究,并对模型模拟精度进行验证。结果表明:模型确定性系数>0.85,模拟结果可信度高;小流域侵蚀模数为2359.24t·km-2·a-1,属于轻度侵蚀,侵蚀主要源于15°以上坡面,占侵蚀总量的92.1%;土壤侵蚀模数随坡度先逐渐增加,当坡度>45°时,土壤侵蚀模数有减小的趋势;土壤侵蚀模数空间异质性显著,坡耕地侵蚀模数最大,为6112.90t·km-2·a-1;荒草地占总面积33.2%,侵蚀量却达总量的74.9%;59.3%的侵蚀来自阳坡和半阳坡,而阴坡半阴坡仅占流域侵蚀量的16.2%。研究为利用CSLE模型对小流域土壤侵蚀进行空间模拟提供技术范例,为京津水源区土壤侵蚀规律研究及水土保持生态建设提供科学参考。Aiming at the fragile ecological environment and the strong spatial variability and unpredictable occurrence of soil and water loss in the water source areas of Beijing and Tianjin,a case study was conducted on the soil erosion pattern and its modulus in the Dongbeigou watershed in Pingquan County of Hebei Province by using geographic information system（GIS） and Chinese Soil Loss Equation（CSLE）,and the simulation precision of the CSLE was tested.The CSLE had a coefficient of determination higher than 0.85,being highly credible,and the watershed had a soil erosion modulus 2359.24 t · km-2 · a-1,belonging to light degree erosion.92.1% of the total soil loss came from the areas with a slope 15°.The soil erosion modulus increased gradually with slope,but showed a decreasing trend when the slope was 45°.A highly spatial heterogeneity was observed in the soil erosion modulus,being the highest（6112.90 t· km-2·a-1） for sloping cropland.Degraded grassland occupied 33.2% of the total area,but its soil erosion amount accounted for 74.9% of the total.59.3% of soil erosion was from sunny and half-sunny slopes,and only 16.2% of it came from shady and half-shady slopes.This study provided a technical basis for applying CSLE to assess the soil erosion in the water source areas of Beijing and Tianjin,and offered scientific reference for the soil and water conservation in the region.

关 键 词：土壤侵蚀规律 地理信息系统(GIS) 中国水土流失模型(CSLE) 空间模拟 

分 类 号：S157.1[农业科学—土壤学]