基于水土流失的景观格局分析方法

景观格局和生态过程是景观生态学研究的重要内容,但是很多研究只重视景观格局的研究,而忽略了生态过程的研究。文章针对水土流失这一重要生态过程,提出了基于水土流失过程的景观坡度指数和景观空间负荷对比指数,并对黄土高原泾河流域15个子流域的景观格局进行了分析,认为泾河流北部各子流域主要以水土流失的＂源＂景观为主,景观坡度指数大,空间负荷指数小,水土流失风险大;流域南部各子流域上游以＂汇＂景观为主,坡度指数大,中下游以＂源＂景观为主,景观空间分布不均衡,存在一定的水土流失风险;流域东部局部子流域主要以水土流失的＂汇＂景观为主,＂源＂景观相对较小,＂源＂-＂汇＂景观空间分布均衡,水土流失风险小。

Method of landscape pattern analysis based on soil and water loss process

Landscape pattern analysis and its ecological process are main fields in landscape ecology research.Many studies only focus on landscape pattern analysis,while ignoring the importance of ecological processes.Aimed at soil water loss,the paper con-structed landscape slope index and location-weighted landscape contrast index based on soil water loss process,and analyzed the landscape pattern of fifteen watersheds in Jinghe River Basin on the Loess Plateau.Results showed that the landscape in the water-sheds of the northern basin was dominated by soil water loss ＂source＂ landscape with bigger landscape slope indexes and smaller location-weighted landscape contrast index.The risk of soil water loss in those watersheds was very high.The landscape of the upper watersheds in the southern basin was dominated by ＂sink＂ landscape with bigger landscape slope index,while ＂source＂ landscape was dominated in the down reach.＂Source＂ and ＂sink＂ landscapes distributed dis-balance in the watersheds made a risk of higher soil water loss.Landscape in watersheds of the eastern part of the basin was dominated by ＂sink＂ landscape and the ＂source＂ land-scape was small.＂Source＂ and ＂sink＂ landscapes were in spatial balance with low soil water loss risk.