天津市宁河湿地资源动态变化及生态环境影响分析

基于遥感、GIS技术和景观生态学方法,以天津市宁河县为研究区域,在1987年和2005年的TM、ETM遥感数据为信息源的基础上,定量分析了天津市宁河湿地资源动态变化。结果表明:湿地类型的整体构成发生了剧烈变化,自然湿地的面积减少了37.42%、斑块减少了124块,人工湿地的面积增加了14 606.2 hm2。多样性指数和均匀性指数呈降低趋势,优势度指数和破碎度指数呈增加趋势。人为活动是近20年宁河湿地资源动态变化的主要驱动力,天然湿地面积的减少及湿地类型的改变引起地下水文条件的恶化,导致湿地水源逐渐枯竭;湿地资源的变化破坏了生物多样性。

Research on the Change of Ninghe Wetlands and It's Ecological Environment

Based on two sets of TM and ETM data(1987and 2005),and by means of the techniques of remote sensing,geographical information system(GIS),and landscape ecology,this paper studied the dynamic development of wetland landscape patterns from 1987 to 2005 in Ninghe County located in Tianjin,China.The results showed that in the past nineteen years,the integral structure of wetland types in this district has been varied greatly.The decrease of the natural wetland area occupied 37.42% of total area,the number of patches decreased from 347 to 223,while artificial wetland area increased from 5 253.4 to 19 859.6 hm2.Diversity indices decreased from 0.754 1 to 0.730 4.Evenness indices decreased from 0.841 2 to 0.702 7,while dominance indices increased from 0.091 to 0.172 7,fragmentation indices increased from 0.003 9 to 0.004 9.Human activities are the driving forces of the dynamic changes of landscape pattern in Ninghe district during the past 19 years,and changes of the wetlands in Ninghe district caused a series of ecological environmental problems,such as groundwater conditions and biodiversity destructed.