澜沧江源头杂多县1985～2000年土地利用变化分析

Analysis of LUCC of the first county—Zaduo Countyin the source area of Lancangjing River

利用三期（1985、1995和2000年）Landsat TM图像解译结果，应用GIS技术，分析了杂多县土地利用的数量变化和时空变化特征。结果表明：15年期间杂多县土地利用变化具有稳定微动性，但在1985～1995年和1995～2000年两个研究时段的变化特征存在明显差异。1985～1995年，土地利用转移面积为5954．00km^2，占该县总面积的16．47％，转移主要发生在草地内部及草地与未利用地之间，占总转移的93．87％，以高、中覆盖草地输出、低覆盖草地输入为特征。表现为草地数量增加，质量下降；1995～2000年，土地利用变化面积为6027．75km^2，占全县总面积的16．67％，主要转移类型为中低覆盖草地-未利用土地、中覆盖-低覆盖草地、低覆盖草地-中覆盖草地、沼泽地-草地，占总转移面积的90．87％，低覆盖草地向高、中覆盖草地正转移，草地数量减少，质量好转。两个研究时段的土地利用变化集中分布在杂多县东部、西南和西部。

Supported by GIS, the spatial-temporal pattern characters of land-use change in Zaduo County from 1985 to 2000 were analyzed based on Landsat TM digital data. Some interesting and significant findings have been obtained： （1） During the period of 1985-2000, the LUCC in Zaduo County was in small quantity, but the characters during the two periods of 1985-1995 and 1995-2000 were obviously different. （2） During the period of 1985- 1995, the total land - diversion amount was 5 954.00 km^2, accounting for 16.47 % of the total land amount in Zaduo County; land-diversion mainly occurred among different coverage degree grassland or between grassland and non-used land, accounting generally for 93.87 % of the total land-diversion amount; another character was that the amount of grassland was increased but its quality decreased. （3） During the period of 1985-1995, the total land-diversion amount was 6 027.75 km2, accounting for 16.67% of the total land amounts in Zaduo County; the main land-diversion types were from mid or low-coverage degree grassland to nonuesd land, from mid-coverage degree grassland to low-coverage degree grassland, from low-coverage degree grassland to mid-coverage degree grassland and from wetland to grassland, accounting for 90.87 % of the total land-diversion amount; the amount of grassland decreased but its quality increased. At the two periods of 1985 -1995 and 1995-2000, land-use diversion occurred obviously in the east, SW and west part of Zaduo County.