Zhou Ting, Ma Jiao-Jiao, Xu Song-Jun
School of Geography, South China Normal University, Guangzhou 510000, China.
Huan Jing Ke Xue. 2020 May 8;41(5):2496-2504. doi: 10.13227/j.hjkx.202001005.
Wetlands play an important role in maintaining ecosystem functions. Wetlands in China have suffered intensive human disturbance, especially before 2000, resulting in great losses and degradation. Therefore, two national wetland resource surveys were carried out by the Chinese government during 1998-2003 and 2008-2013 to determine the status of wetlands, understand their dynamics, and provide substantial data that can aid scientific wetland conservation. Based on the survey data, the spatial pattern and spatial autocorrelation were explored using the standard deviation ellipse as well as global and local spatial autocorrelation statistics. GIS mapping was employed to display the results via the visualization of the spatial patterns and relationships. Results indicate that:① Changes in the wetlands of China are significant and exhibit obvious regional differences. The center of the ellipse of the total wetlands has moved to the west, and the degree of spatial differentiation between natural wetlands and artificial wetlands is increasing. There is no significant spatial autocorrelation for changes in artificial wetlands. ② The changes in natural wetlands are significantly spatially autocorrelated and clustered, which are identified by global Moran's and local Moran's . The hotspots of natural wetland change are concentrated primarily in Qinghai, Tibet, and Sichuan. The individual hotspot is in Inner Mongolia and the cold spot is in Henan. The difference in spatial autocorrelation between natural and artificial wetland changes indicates that natural wetland changes have shown spatial continuity, while artificial wetland changes have shown strong spatial randomness. ③ Some useful spatial associations are used to delineate wetland conservation effects. Then, three major or five minor effective protection management regions are identified. Wetland conservation efforts should be continuously strengthened and improved, especially in the middle-lower Yangtze River region of central China. The use of Moran statistics helps to reveal spatial autocorrelation and identify the conservation effects in wetland changes, which can provide a basis for decision-making in regional wetland conservation and management systems.
湿地在维持生态系统功能方面发挥着重要作用。中国的湿地遭受了强烈的人类干扰,尤其是在2000年以前,导致了巨大的损失和退化。因此,中国政府在1998 - 2003年和2008 - 2013年期间进行了两次全国湿地资源调查,以确定湿地状况,了解其动态变化,并提供有助于科学保护湿地的大量数据。基于调查数据,利用标准差椭圆以及全局和局部空间自相关统计方法探索了空间格局和空间自相关性。采用地理信息系统(GIS)制图通过空间格局和关系的可视化来展示结果。结果表明:①中国湿地变化显著且呈现出明显的区域差异。总湿地椭圆中心已向西移动,天然湿地和人工湿地之间的空间分化程度在增加。人工湿地变化不存在显著的空间自相关性。②天然湿地变化在空间上具有显著的自相关性且呈聚集状态,这通过全局莫兰指数(Moran's I)和局部莫兰指数(Local Moran's I)得以识别。天然湿地变化的热点主要集中在青海、西藏和四川。个别热点在内蒙古,冷点在河南。天然湿地和人工湿地变化在空间自相关性上的差异表明,天然湿地变化呈现出空间连续性,而人工湿地变化呈现出强烈的空间随机性。③利用一些有用的空间关联来划定湿地保护效果。然后,确定了三个主要或五个次要的有效保护管理区域。应持续加强和改进湿地保护工作,特别是在中国中部的长江中下游地区。莫兰统计量的使用有助于揭示空间自相关性并识别湿地变化中的保护效果,可为区域湿地保护和管理系统的决策提供依据。