黑龙江省黑土区水土流失动态及成因分析

Dynamics and Causes of Soil and Water Loss in Black Soil Region of Heilongjiang Province

为了解不同时期黑龙江省黑土区水土流失状况及其演变动态,根据历史调查资料、小流域原位勘察结果及同期遥感调查数据,分别对1950,1980和2000年黑龙江省黑土区50a来不同空间尺度水土流失状况、特征、成因及演变进行分析。结果表明:(1)该区水土流失面积50a来净增了2.08×104 km2,水蚀是造成该区水土流失主要形式。(2)1950—1980年20a间年均水土流失面积为411.9km2,比1980—2000年年均值高出25.5km2。(3)50a来该区侵蚀沟数量增加98 832条,2000年侵蚀沟面积所占比例比1950年增加了172.4%,沟壑密度增加2.83倍。该区水土流失呈持续恶化态势,不合理人类活动、政策导向和黑土质量退化是导致该区水土流失程度动态变异主要诱因。

In order to understand soil and water loss and its dynamic changes in the black soil region, the dynamic characteristics and causes of soil and water loss during a period of 50 years （1950, 1980 and 2000） were analyzed in Heilongjiang Province, by investigating the historical information, small watershed survey, and remote sensing data analysis. The results indicated that： （1） The area of soil and water loss increased by 2.08×10^4km2 in the past 50 years, and water erosion contributed the most for the erosion. （2） During the period from 1950 to 1980, the area of soil and water loss was 411.9 km2 , while it was 386.4 km2 during the period from 1980 to 2000. （3） The number of erosion gully increased 98 832 during the past 50 years, the area of erosion gully increased by 172.4 %, and the density of gully increased by 2.83 times. The deterioration of soil and water loess was attributed to the uncontrolled anthropic activities, policy direction by local government and deterioration of black soil physical properties in this region.