漓江流域2000-2020年土地利用和覆被变化时空分异特征

Spatial and Temporal Characteristics of Land Use and Land Cover Change in Lijiang River Basin During 2000-2020

[目的]分析2000—2020年漓江流域土地利用和覆被变化时空分异规律,为协同人类活动及生态安全提供空间治理依据。[方法]基于遥感信息识别和GIS空间分析平台,应用扩张强度、转移矩阵及时空统计、空间自组织分析等方法,从多维时空尺度研究流域土地利用及景观结构变化规律。[结果]①漓江流域以林地、耕地为主体景观,合占景观面积的比例超过90%,2000—2020年其面积变率小于0.37%,扩张强度小于年均3.59%,表明流域具有高质量的景观生态资源和建成国际旅游中心的生态资本,景观结构稳定,水生态良好;②建设用地增长最快,扩张显著,2000—2020年其面积增长了163.41%,其中临桂新区年均扩张37.79%,城镇化是流域景观类型及结构变化的主要驱动;③流域景观类型多样性丰富、分布均衡,多样性和均匀度指数在城镇及旅游中心形成高值中心,山地区则为低值连片;连通性或延展性较好,山区为高值中心,城镇为低值中心,人类活动对草地形态及城镇周边(中值区)的扰动较显著。[结论]流域景观指数结构受相似的发生环境和分异因素影响而具有空间集聚性分布特征,城镇扩张及旅游活动是漓江流域景观格局分异的主要驱动,区域发展较适合集中城镇化与分散旅游业模式。

[Objective]The temporal and spatial differentiation of land use and land cover change of the Lijiang River basin during 2000—2020 was analyzed in order to provide a basis for spatial governance for coordinated human activities and ecological security.[Methods]Based on remote sensing information identification and GIS spatial analysis platform,expansion intensity,transition matrix and time-space statistics and spatial self-organization methods were used to study the changing laws of land use and landscape structure.[Results]①The main landscape of the Lijiang River basin was forest land and cultivated land,accounting for more than 90%of the landscape area.During 2000—2020,the area change rate was less than 0.37%,and the expansion intensity was less than 3.59%per year,indicating that the watershed had high-quality landscape ecology resources and ecological capital to build an international tourism center.Besides,its landscape structure was stable,and water ecology was good.②Construction land had the fastest growth and significant expansion.Its area increased by 163.41%during 2000—2020,of which the average annual expansion of Lingui New District was 37.79%.Urbanization was the main driving force for landscape type and structural changes,and the water ecosystem was well maintained.③The watershed landscape types were rich in diversity,the landscape distribution was balanced.The diversity and evenness index formed a high-value center in cities and towns and tourism centers,while in mountainous areas,it was a low-value continuous area.The connectivity was good,the mountainous area was the high value center and the town was the low value center.Human activities had a significant disturbance to the grassland shape and the surrounding area of the town(median area).[Conclusion]The watershed landscape index structure is affected by similar occurrence environment and differentiation factors and that has spatial agglomeration distribution characteristics.Urban expansion and tourism activities are the main drivers of the differentiation of the landscape pattern of the Lijiang River basin.Regional development is more suitable for centralized urbanization and decentralized tourism.