基于GIS技术的拉萨市城关区荒漠分类研究

目的] 尝试在青藏高原县级尺度上对荒漠化区域进行划分，并分析不同荒漠类型的分布特征，为荒漠区划及荒漠化防治工作提供科学依据。方法] 以西藏自治区拉萨市城关区为例，利用2018年的TM遥感影像，2000—2018年的MODIS影像数据，结合GIS制图技术，通过长期野外调查，探讨高寒区荒漠分类系统。结果] 在分析荒漠形成主要影响因素的基础上，提出荒漠分类的主要原则和划分指标。利用气候区划、地表物质组成、地貌形态及成因、植被盖度等指标，将拉萨市城关区荒漠划分为2个Ⅰ级类型，7个Ⅱ级类型，18个Ⅲ级类型，31个Ⅳ级类型，并确定各级各类荒漠的面积及空间分布范围。结论] 确定了高寒区荒漠分类的指标，对城关区的荒漠区域进行分级分类。初步建立了西藏高寒地区的荒漠分类体系，奠定了青藏高原高寒区荒漠分类研究的基础。

Desert Classification of Chengguan District of Lhasa City Based on GIS Technology

Objective] In order to provide scientific basis for desert regionalization and desertification control, this paper tries to classify desertification areas on the county scale of the Qinghai-Tibet Plateau and analyze the distribution and characteristics of different desert types.Methods] Based on TM images from 2018, MODIS images from 2000 to 2018, combined with GIS mapping technology and long-term field investigation, the study selected Chengguan District of Lhasa City as a case to explore the desert classification system in the alpine region.Results] According to the main influencing factors of desert formation, the main principles and indexes of desert classification were put forward. Based on the indexes of climate regionalization, surface material composition, geomorphic morphology, and vegetation coverage, the desert in the Chengguan District of Lhasa City was divided into 2 first-level types, 7 second-level types, 18 third-level types, and 31 fourth-level types, and the area and spatial distribution of each desert type were determined.Conclusion] This study determines the index of desert classification, and classifies the desert area of the Chengguan District. The desert classification system in the Qinghai-Tibet Plateau is preliminarily established, which is the basis for the alpine classification research in the Qinghai-Tibet Plateau.