海口市海岸带生态系统服务及其时空变异

海岸带位于陆地、海洋交汇地带,有着重要的生态价值,但也是生态环境较为脆弱的地区。以海口市为研究区,研究海口市海岸带生态系统服务及其时空变异。基于1990、1995、2004和2012年4期Landsat TM影像得到土地利用覆盖数据;采用基于当量因子的生态系统服务价值评价方法,结合海口市实际情况,构建了海口市海岸带生态系统服务价值动态评估模型;借助GIS空间分析技术,应用局部空间自相关模型,定量研究了生态系统服务价值(ESV)的时空变异特征。研究结果表明:(1)在生态系统服务的总值方面,过去20多年的ESV整体变化不大,但近年来ESV有所降低,生态环境出现退化趋势。(2)在生态系统服务的时空变异方面,海口市海岸带ESV的空间正相关性显著,空间集聚程度较高,高值区主要集中于中心城区西部和东寨港周围,低值区主要集中于中心城区;近来,在发展城市经济和保护生态环境的双重作用下,位于中心城区的低值区和位于东寨港红树林自然保护区的高值区都有所辐射扩张。

Coastal ecosystem services and their spatial-temporal variation in Haikou, China

The coastal zone is in the land-ocean interaction area, which has great ecological importance and the ecological environment of this zone is often vulnerable. In the present research, the coastal zone in Haikou, China was selected as a case study to explore the coastal ecosystem services and their spatial-temporal variation. Firstly, four Landsat TM images collected in 1990, 1995, 2004, and 2012 are interpreted to obtain the land use/cover data. Secondly, based on the equivalent factor method of Ecosystem Services Values (ESV) evaluation and the local conditions, a dynamic assessment model of ecosystem services values in the Haikou coastal zone was constructed. Finally, using GIS-based spatial analysis technology and the local spatial autocorrelation model, the spatial-temporal variation characteristics of Ecosystem Services Values were quantitatively studied. Analysis of the results indicated: (i ) Change in ESV in the past twenty years has been insignificant, with ESV decreasing in recent years; thus the ecological environment has shown a trend of degradation; (ii) the spatial-temporal variation of ESV in the Haikou coastal zone is clear: spatial correlation is significant and the degree of spatial agglomeration is relatively high. High values are mainly distributed in the western part of the downtown area, and surrounding Dongzhaigang, whereas low values are mainly distributed in the downtown area. Recently, under the dual-strategy of economic development and environmental protection, both the low value downtown area and the high value Dongzhaigang mangrove nature reserve area have experienced continuous radiation expansion.