基于TM影像的升金湖湿地生态安全研究

Research on Wetland Ecological Security of Shengjin Lake Based on TM Images

[目的]分析安徽省升金湖湿地景观格局动态变化过程,建立升金湖湿地生态安全(PSR)模型,并探讨其驱动力,为进一步开展升金湖湿地保护及其恢复研究提供科学依据。[方法]在遥感和GIS技术支持下,用1986,2003,2011年的3期TM影像为基本信息源进行分析。[结果]景观格局变化幅度较大,草地和水域面积减幅较显著;多样性指数呈上升趋势而优势度指数呈下降趋势,破碎化程度加剧,斑块类型呈多样性发展;随着景观破碎化程度增强,斑块数增加,将造成湿地生态系统片断化越严重,也会影响到湿地的调蓄能力,改变整个湿地的水文情势,减弱湿地的生态效益;另外,景观格局变化下的湿地生态安全指数趋于逐年下降状态,湿地生态安全形式处于预警状态,形势不容乐观。[结论]近年来,随着经济的发展,人口数量的增加,围垦等活动的加剧,人类活动对研究区的改造导致了自然湿地面积相对减少,升金湖湿地生态功能不断下降,经济增长和人口增长成为湿地格局变化主要驱动力。

[Objective]We analyzed the dynamic change of landscape pattern of Shengjin Lake in Anhui Province.Ecological security model was established and the driving forces that influence the landscape pattern change were discussed to provide the scientific basis for protecting and recovering Shengjin lake wetland.[Methods]Based on remote sensing and GIS technology,we used TM images in 1986,2003 and 2011to analyze the ecological security.[Results]The land use pattern in Shenjin Lake changed greatly.The area of grassland and water decreased dramatically.The diversity index increased while the dominance index declined.The intensified fragmentation in landscape pattern had significantly influenced the regulation and storage capacity of the wetland resources.In addition,the index of wetland ecological security tended to decline year by year.[Conclusion]Due to human activities,the area of nature wetland is reducing,and ecological function is declining.Growths in economy and population are the main driving forces that influence the dynamic change of landscape pattern in Shengjin Lake wetland.