粤港澳大湾区湿地生态风险评估

Wetland Ecological Risk Assessment of Guangdong-Hong Kong-Macao Greater Bay Area

为了整体把握粤港澳大湾区湿地生态系统风险水平,以GlobeLand30地表覆盖产品、气温和降水站点数据、MODIS NDVI产品和人口、GDP、粮食作物单产等统计资料为主要数据源,基于PSR模型,采用层次分析法(AHP)构建湿地生态风险评估体系,分析湿地的外界压力、自身状态和响应指标的变化特征,并对2000-2020年大湾区湿地生态风险进行综合评估。结果表明:(1)该区域湿地生态压力变化呈现先下降后增长的趋势,经济的快速发展和城市扩张是影响湿地生态风险的主要压力因素;(2)湿地生态风险的状态水平逐渐下降,呈现“外高内低”的分布格局,景观内部破碎化相对严重。生态响应水平波动较小,但整体生态系统服务价值呈下滑趋势;(3)粤港澳大湾区2000年、2010年和2020年湿地生态风险评估值分别为0.470、0.426和0.418,风险水平为“较高风险”。高风险地区比重下降了21.15%,中风险区域提升了约11.54%。从空间上看,西部和东部地区湿地生态风险显著降低,大部分城市的风险水平处于中等或者较高等级。粤港澳大湾区湿地资源的修复和管理面临众多挑战,建议处理好城市建设和湿地保护的矛盾、提升公众保护意识、注重与非湿地系统的调控并完善相关制度,更好地协调湿地生态条件和社会经济发展之间的关系,服务于粤港澳大湾区建设的国家战略需求。

Wetlands play an important role in maintaining the ecological integrity of the Greater Guangdong-Hong Kong-Macao Bay Area.A full vision of the risk level of the wetland ecosystem of this large bay will provide reference for conservation and restoration of the wetland ecosystem and support sustainable development.In this study,we developed an ecosystem health evaluation system for the wetlands of the bay area,based on a pressure-state-response(PSR)model and the analytic hierarchy process(AHP).The model was then used to evaluate the ecological risk of the wetlands during the period 2000-2020.Changes in wetland ecological indicators of pressure,and their state and response level were comprehensively analyzed.PSR model development was accomplished using GlobeLand30 surface cover and MODIS NDVI software,and primary data included temperature,precipitation,population,GDP,grain output per unit of land as well as other statistics for 2000,2010 and 2020.Results show:(1)The pressure on wetland ecology declined over the first decade and then increased,with average values for 2000,2010 and 2020 of 0.106,0.104 and 0.110 respectively,and rapid economic development and urban sprawl were the primary pressure elements affecting wetland ecological risk.(2)The state level of the wetland ecological system gradually decreased,and the average values for 2000,2010 and 2020 were 0.231,0.188 and 0.175,showing a distribution pattern of“high outside and low inside”,and fragmentation of the landscape was relatively serious.The response level of the wetland ecological system fluctuated only slightly,with average values of 0.133,0.134 and 0.134 in 2000,2010 and 2020,while the overall ecosystem service value was declining.(3)The assessment values of wetland ecological risk for the Greater Guangdong-Hong Kong-Macao Bay Area in 2000,2010 and 2020 were 0.470,0.426 and 0.418,indicating a relative high risk.The proportion of high-risk areas decreased by 21.15%and the proportion of medium-risk area increased by 11.54%.In terms of the spatial distribution,the ecological risk of the wetland in the western and eastern regions significantly decreased,but the ecological risk in most cities were remained at medium or high levels.The restoration and management of wetland resources in the Greater Bay Area faces many challenges.To seek for a better relationship between wetland ecology and social economic development and to support the national strategic demands for construction in the area,it will be necessary to effectively balance urban construction with wetland protection,promote public awareness of wetland conservation,focus on the regulation and control of non-wetland systems and improve the relevant system.