关键词: 长江口, 芦苇, 底栖动物, 优势种, 生境价值

Abstract: Soil erosion has caused serious ecological and environmental problems in Chengdu-Chongqing Economic Zone, such as soil loss of productive land, soil nutrient loss, and river silting, which restricts the sustainable development of the economic zone. Based on GIS and RUSLE model, soil erosion in 2000, 2005 and 2010 was calculated, and the spatiotemporal pattern and variation were also analyzed. During the period of 2000 to 2010, the mean modulus and amount of soil erosion showed an increasing trend in ChengduChongqing Economic Zone. Spatially, slightly intense soil erosion occurred on more than 90% of the total land, which implies general situation of the soil erosion of the whole area was not yet serious. However, soil erosion was aggravated from 2000 to 2005 and 2010, caused by the acceleration of urbanization and unreasonable land use. During the period of 2000 to 2010, the transformation of slightly intense soil erosion was not obvious, but the transformation of the other different levels of soil erosion was obvious. More than 50% of slight, middle, intense and extremely intense soil erosion was alleviated to lower levels from 2000 to 2005, however, 70% of low level soil erosion was aggravated from 2005 to 2010. More than 30% of slight, middle, intense and extremely intense soil erosion was aggravated to higher levels from 2000 to 2005, however, only 20% was aggravated from 2005 to 2010. It implies that after the implementation of the reforestation project, the soil and water conservation had been improved in some areas. Therefore, it is suggested that the government should insist on scientific development and sustainable utilization of natural resources, establish a complete ecological compensation framework, maintain the balance between supply and demand of human beings and natural environment, strengthen the comprehensive soil and water conservation, and reduce water loss and soil erosion.

Key words: zoobenthos, habitat value, Yangtze River estuary, Phragmites australis, dominant species