黄河流域景观破碎化时空特征及其成因探测

黄河流域快速的人口增长和城市扩张加剧了土地利用转型和生态景观破碎化，引发了诸如生态系统功能退化、生物多样性功能减弱以及生境破碎化等一系列严重问题。探明黄河流域景观破碎化时空特征及其成因对维护流域生态系统稳定和生态修复具有重要指导意义。但是以往研究缺乏对黄河流域景观破碎化时空特征及其归因分析的相关研究，难以为黄河流域生态环境治理以及景观格局优化提供科学指导。基于FRAGSTATS4.2软件测度了2000—2018年黄河流域县域单元景观破碎化时空格局特征，并借助地理探测器模型探讨了黄河流域景观破碎化时空分异的成因。研究表明：(1)研究期间黄河流域斑块密度(PD)无显著变化，边缘密度(ED)、景观形状指数(LSI)、平均斑块面积(Area＿AM)均呈先增后减的变化趋势，聚集度指数(AI)呈先减后增的趋势；蔓延度指数(CONTAG)持续降低，分离度(DIVISION)、香农多样性指数(SHDI)逐年增高。(2)研究期间黄河流域景观破碎化程度总体逐渐加剧，流域中下游各省破碎化程度变化剧烈，上游各省破碎化程度变化趋于平稳。(3)地理探测器结果显示，黄河流域景观破碎化受到自然、社会等多重因素影响，因...

Spatiotemporal patterns of landscape fragmentation andcauses in the Yellow River Basin

Rapid population growth and urban expansion in the Yellow River Basin have aggravated land use transition and landscape fragmentation, resulting in a series of severe problems, such as the degradation of ecosystem function, reduction of biodiversity function, and the fragmentation of habitat. Exploring the spatio-temporal characteristics and causes of landscape fragmentation in the Yellow River Basin has important guiding significance for maintaining the stability of ecosystem, ecological restoration, and ecological civilization construction in the Yellow River Basin. However, previous studies lacked the knowledge of spatiotemporal characteristics and formation mechanism of landscape fragmentation, which is difficult to provide scientific guidance for the ecological governance and landscape pattern optimization of the Yellow River Basin. Based on Fragstats4.2 software, this study analyzed the spatiotemporal pattern of landscape fragmentation at county level of the Yellow River Basin from 2000 to 2018, and explored the formation mechanism of spatiotemporal differentiation of landscape fragmentation with the help of geodetector model. The results showed that:(1) patch density(PD) of the Yellow River Basin had no significant change during the study period. The edge density (ED), landscape shape index (LSI), and patch area mean (Area_AM) showed a trend of increasing at first and then decreasing. The aggregation index (AI) showed a trend of decreasing at first and then increasing. The index of contagion (CONTAG) continued to decrease, while the landscape division index (DIVISION) and shannon''s diversity index (SHDI) increased gradually. (2) The degree of landscape fragmentation in the Yellow River Basin increased gradually during the study period. The degree of landscape fragmentation in the middle and lower reaches of the Yellow River Basin changed sharply, while the degree of landscape fragmentation in the upper reaches of the Yellow River Basin tended to be stable. (3) According to the results of geodetector, the fragmentation of the landscape in the Yellow River Basin was affected by multiple factors such as nature and society, among which there was a significant interaction enhancement effect. The main influencing factors of different regions are obviously different, while the intensity of human activities is the leading one. The results can provide ideas for exploring the formation mechanism of landscape fragmentation in the river basin, and have important referential significance to the ecological governance, ecosystem protection, and land use planning formulation of the Yellow River Basin.