【摘要】 青藏高原被称为世界"第三极",人类土地利用活动和气候变化对青藏高原陆地生态系统产生重要影响.基于1990～2015年间每5年的30米分辨率土地利用/覆盖变化遥感监测数据,对青藏高原生态系统宏观结构以及动态变化进行时空特征分析.研究表明:青藏高原生态系统面积最大的是草地生态系统,聚落生态系统面积最小;25年间,农田生态系统先增加后减少,面积净减少194.79 km~2,减少速度为7.79 km~2/a;森林生态系统经过增加减少再增加又减少后,面积净减少516.60 km~2,减少速度为20.66 km~2/a;草地生态系统先减少后增加再减少,面积净增加296.54 km~2,增加速度为11.86 km~2/a;聚落生态系统保持持续增加,面积净增加316.34 km~2,增加速度为12.65 km~2/a;农田、森林、草地转变主要发生在川西藏东高山深谷地区,城乡聚落的变化主要发生在藏南山地、果洛那曲丘状高原、川西藏东高山深谷.更多还原

【Abstract】 The Qinghai-Tibet plateau is known as the "third pole" of the world. Human land use activities and climate change have an important impact on the terrestrial ecosystem of the Qinghai-Tibet plateau. Based on the remote sensing monitoring data of land use/cover change with a resolution of 30 meters every five years from 1990 to 2015, this study analyzed the spatial and temporal characteristics of the macro-structure and dynamic changes of the ecosystem on the Qinghai-Tibet plateau. The study showed that the grassland ecosystem is the largest and the settlement ecosystem is the smallest during the 25 years. The farmland ecosystem first increased and then decreased, with a net area reduction of 194.79 km~2 and a reduction rate of 7.79 km~2/a. After several increases and decreases of the forest ecosystem, the net area decreased by 516.60 km~2, and the reduction rate is 20.66 km~2/a. Grassland ecosystem decreased first, then increased and then decreased, with a net area increase of 296.54 km~2 and an increase rate of 11.86 km~2/a. The settlement ecosystem keeps increasing, with a net increase of 316.34 km~2 and an increase rate of 12.65 km~2/a. The transformation of farmland, forest and grassland mainly occurred in the mountainous and deep valleys of eastern Tibet and western Sichuan, and the change of urban and rural settlements mainly occurred in the mountainous areas of southern Tibet, the hilly plateau of Guolonanqu, and the alpine and deep valleys of eastern Tibet and western Sichuan.更多还原