三明地区景观格局变化分析及生态风险评估

Analysis of Landscape Pattern Change and Ecological Risk Assessment in Sanming Area

随着城市不断扩张,生态景观格局发生了较大的变化。三明地区地形以山地丘陵为主,景观格局较为复杂,对该地区进行景观格局变化分析,在此基础上进行生态风险评估对保障生态安全具有重大意义。本研究以2015年地理国情普查的土地覆盖数据为基础,依据2005年高分辨率影像进行逆向变更得到2005年土地覆盖矢量数据;利用分析方法进行土地覆盖类型变化的景观格局相关指标计算,探讨三明地区2005—2015年间生态景观格局的时空变化,以揭示三明地区景观变化规律;通过景观干扰指数(Ei)和景观脆弱度指数(Fi)定量评估得出该地区生态风险值的时空分布。结果表明:研究期间,三明地区的景观格局变化较为轻微,主要体现为自然景观向人工景观的转变,人工景观覆盖面积不断扩大,整体景观呈现破碎化的态势,总体的风险值也有攀升的趋势。

With the urban expansion,the ecological landscape pattern has changed greatly.The terrain of Sanming area is mainly mountainous and hilly,with complex landscape pattern.It is of great significance for ecological security to analyze the landscape pattern of Sanming area and to evaluate the ecological risk.Based on the data of geographic and national census,this study selected the image and land cover vector data of 2005 and 2015,and discussed the spatial and temporal changes of ecological landscape pattern in Sanming area through the calculation of landscape pattern related indicators and land use type change indicators,so as to reveal the law of landscape change in Sanming area.The spatial and temporal distribution of ecological risk value in this area was obtained by quantitative assessment of pattern correlation index.The results showed that during the study period,the landscape pattern of Sanming area changed slightly,mainly reflected in the transformation from natural landscape to artificial one,and the coverage area of artificial landscape expanded continuously.The overall landscape is becoming fragmented,and the overall risk value is also rising.