1990-2018年海南岛湿地景观生态安全格局演变

Dynamic Analysis of Wetland Landscape Ecological Security Pattern of Hainan Island in 1990-2018

海南岛是中国重要的生态功能区,在国家战略背景下,湿地景观呈现多样化的利用方式。科学评估海南岛湿地景观生态安全格局,对湿地资源进行有效保护是实现可持续发展的重要保障。以海南岛为研究区,基于PSR模型构建海南岛湿地景观生态安全评价体系,采用层次分析法确定指标权重,利用1990、2000、2010、2018年4期Landsat遥感影像的湿地解译数据,以及人口、经济等指标为数据源,在遥感和GIS技术的支持下分析了1990-2018年海南岛湿地景观生态安全状况及其空间分布特征。结果表明,(1)1990-2018年间,海南岛湿地景观总面积呈增长趋势,总面积由1990年的944.36 km2增加到2018年的1 337.57km2。其中,人工湿地呈明显增长趋势,自然湿地则呈减少趋势;各市县湿地面积增长最多的是文昌、东方、海口和儋州等。(2)海南岛湿地景观生态安全指数(LESI)在总体上呈下降趋势,安全等级由临界安全演变为较危险状态,且在2010-2018年间LESI变化较大;至2018年,总体上呈现出"海南岛北部和南部市县的LESI低,中部山区市县的LESI高"的空间分布格局。(3)采用自然断点法将1990-2018年海南岛湿地LESI变化幅度分为4个级别,LESI值降幅最大的为海口、三亚、文昌、澄迈4个经济发达市县;保亭、白沙、乐东和琼中4个中部市县的LESI值则略微提升。提出严格实施湿地资源规划分区分级管控和湿地生态修复工程,维护和强化湿地生态空间的连续性和完整性。

Hainan Island was an important ecological function zone in China. In the context of national strategy, wetland landscape presents diversified utilization methods. Scientific assessment of the ecological security pattern of the wetland landscape in Hainan Island, and effective protection of wetland resources were important guarantees for achieving sustainable development. This paper takes Hainan Island as the research area, constructs Hainan Island wetland landscape ecological security evaluation system based on PSR model, uses AHP to determine index weight, and uses wetland interpretation data of Landsat remote sensing images in 1990, 2000, 2010 and 2018, and the indicators such as population and economy were data sources. With the support of remote sensing and GIS technology, the ecological security status and spatial distribution characteristics of Hainan Island wetland landscape from 1990 to 2018 were analyzed. The three major results are as follows:(1) From 1990 to 2018, the total area of wetland landscape in Hainan Island increased, and the total area increased from 944.36 km2 in 1990 to 1 337.57 km2 in 2018. Among them, the artificial wetland showed a significant growth trend, while the natural wetland showed a decreasing trend, the largest increase in the wetland area of the city was Wenchang, Dongfang, Haikou and Danzhou.(2) The landscape ecological security index(LESI) of Hainan Island wetland was generally declining, the security level changes from critical security to a more dangerous state, and LESI changes greatly between 2010 and 2018. In 2018, there was an overall spatial pattern of "low LESI in the north and south cities of Hainan Island, and high LESI in the middle mountainous cities". And(3) using natural breakpoint method, the variation range of LESI in Hainan Island wetland from 1990 to 2018 was divided into four levels. The largest decline in LESI value was Haikou, Sanya, Wenchang and Chengmai, four economically developed cities. The LESI values of the four middle cities of Baoting, Baisha, Ledong and Qiongzhong increased slightly. In order to maintain and strengthen the continuity and integrity of wetland ecological space, it was proposed to strictly implement the zoning and grading control of wetland resource planning and wetland ecological restoration project.