浙江省水土流失的时空动态研究

Temporal and Spatial Variation of Soil and Water Loss in Zhejiang Provence

浙江省大量基础设施建设项目的开工建设,在不同地区和不同建设工期表现出的水土流失特征各不相同,且不同的土地利用方式和利用强度造成的水土流失类型和规律也不相同,充分体现了经济发达地区不同于过去和经济相对落后地区的水土流失特征。经济发达地区的水土流失特征可归纳为:水土流失面积小、强度大,强度水土流失空间分布分散、时间集中性强、动态变化速度快,水土流失治理效益显著,人为诱发水土流失突出。出现上述特征的原因可概括为:开发建设项目不同工期水土保持措施效益差异是强度水土流失面积波动的原因之一,经济开发和劳动力转型是水土流失面积减少的原因之一,农业经济林开发建设是导致林地水土流失比重大的原因之一。提出了今后水土保持工作应采取的新措施和重点治理的新方向。

The characteristics of soil and water loss occurred in different areas or different construction periods during the construction of infrastructures started in Zhejiang Province are different and the types and the patterns of soil and water loss caused by different land use types and different utilization intensity are also different.It fully shows that the characteristics of soil and water loss occurred in developed areas are differ from that be of in the past or in undeveloped areas.The characteristics of soil and water loss occurred in developed areas can be concluded as a) soil and water loss occur in small area but it has great intensity;b) spatial distribution of intensity soil and water loss is scattered,and occurrence time is concentration,and dynamic change is fast;c) the benefits of soil and water loss treatment are remarkable and;d) artificial induced soil and water loss is notable.The reasons for the above characteristics can be concluded as a) the different benefits of soil and water conservation measures in different construction periods is one of the reasons for the area variation of intensity soil and water loss;b) the economic development and the labor force transformation are two reasons for the area reduction of soil and water loss and;c) planting economic trees is one of the reasons for causing intense soil and water loss in woodlands.It puts forward new measures that should be adopted in soil and water conservation work and new orientation for key treatments in the future.