三江源区土地利用和景观格局变化分析

通过对2000年以来3期TM／ETM遥感影像解译，获取三江源区土地利用类型数据集，依此分析三江源区近10年来土地利用和景观格局的变化特征。结果表明：从2000年至2010年三江源区土地利用变化相对缓慢，整体上比较稳定，草地、林地、湿地和人工用地的动态度均小于0．5％，其类型之间的转化强度约为0．5％；从土地利用综合动态度和转化强度方面看，三江源区后5年的变化明显低于前5年，表明三江源区整体变化在减慢，土地利用趋于稳定。草地景观和其他类景观斑块面积比下降，导致研究区优势景观类型衰减，区域景观类型增加，各类景观类型呈均衡化趋势发展，号观趋于多样化；景观连续性降低，不同景观类型之间呈现相间团聚分布，景观趋于破碎化。

Analyses on Change of Land Use and Landscape Pattern in the Three-River Headwater Region

The variation characteristics of land use and landscape pattern in the Three-River Headwater Region during recent ten years were analyzed through the data sets of land use types of the region based on the interpreta- tion of remote sensing image by three time periods of TM/ETM images since 2000. The results showed that the change of land use in the Three-River Headwater Region was relatively slow and the overall land use status was rel- atively stable from 2000 to 2010. the average dynamic degree of the grassland, woodland, wetlands and artificial land was all less than 0.5 % , and the change index of land use among different types was around 0.5 %. The ana- lyses on integrated dynamic degree and change index of land use showed that the change in the later five years was significantly less than that of in the previous five years, indicating that the overall change in land use types in the Three-River Headwater Region was slowed down, and the land use and landscape pattern trended to be stable. The ratio of grassland landscape to other types of landscape patchs in the study area was decreased, which led to the de- cline of predominant landscape types, the increase of regional landscape types, equalized development of different landscape types and the landscape became more diversified. Meanwhile, the continuity of landscape was reduced, there were aggregated distribution of different landscape types, and the landscape tended to be fragmented.