基于INVEST模型的洞庭湖区土地利用景观格局对生境质量的影响研究

Research on the impact of land use and landsacpe pattern on habitat quality in Dongting Lake area based on INVEST model

生境质量是区域生物多样性维持能力的重要表征,土地利用变化是引起景观格局和生境质量变化的主要原因,揭示土地利用及景观格局变化下生境质量的时空演变规律能为生物多样性保护提供参考依据。以洞庭湖区为研究对象,基于1995、2000、2005、2010、2015、2018年6期遥感解译数据,采用土地利用转移矩阵、景观格局指数及INVEST模型等方法,分析近年来洞庭湖区土地利用和景观破碎度变化对生境质量的影响。结果表明:(1)研究区段内,洞庭湖区湿地、建设用地增加比例为0.5%、44%,耕地、林地减少比例为2.7%、1.6%;(2)耕地、林地破碎度都有所增加,湿地的破碎度呈现“升高-降低-升高”的N型”波动趋势;(3)时间上看,六个不同时期洞庭湖区生境质量分别为0.563、0.561、0.562、0.563、0.556、0.554,经历了“降低-升高-降低”的“倒N型”波动趋势,生境质量的提高与湿地的大量转入以及湿地破碎度的降低有关,生境质量的降低与城镇开发占用大量耕地、林地以及主要生境类型(耕地、林地、草地)破碎度增加有关;(4)空间上看,生境质量与景观破碎度的变化范围大致相同,景观破碎度增加的地区,生境质量明显降低。1995-2010年生境质量的变化主要体现在湖体附近包括岳阳市市区、华容县、沅江市、南县、湘阴县,2010-2018年生境质量的变化体现在各县市城镇用地附近;(5)处理好“三生空间”之间的关系,实施严格的湿地保护措施,促进湖区生态保护和经济高质量发展,是提高洞庭湖区生境质量的必由之路。

Habitat quality is an important indicator of regional biodiversity maintenance capacity.Land use is the main reason of the change of landscape pattern and habitat quality,revealing the spatiotemporal evolution of habitat quality under the change of land use and landscape pattern can provide a reference for biodiversity protection.Taking the Dongting Lake area as the research object,and useing transfer matrix of land use,landscape pattern index and INVEST model to quantitatively analyze the impact of land use and landscape fragmentation on habitat quality in the Dongting Lake area,based on the remote sensing interpretation data of 1995,2000,2005,2010,2015,2018.The results show that:(1)In the study section,the increase rates of wetland and construction land in Dongting Lake area are 0.5%and 44%,and the decrease rates of cultivated land and forest land are 2.7%and 1.6%.(2)The degree of fragmentation of cultivated land and forest land has increased,and the degree of fragmentation of wetland has shown an"increasing-decreasing-increasing""N-type"fluctuation trend.(3)In terms of time,the habitat quality of the Dongting Lake area in six different periods is 0.563,0.561,0.562,0.563,0.556,0.554,respectively,experiencing the"inverted-N"fluctuation trend of"decrease-raise-decrease",and the improvement of habitat quality is related to the transfer of wetlands and the decrease of wetland fragmentation.The decrease in habitat quality is related to the large amount of cultivated land and forest land occupied by urban development and the increased fragmentation of the main habitat types(cultivated land,forest land and grassland).(4)From a spatial perspective,the range of change of habitat quality and landscape fragmentation is approximately the same.In areas where landscape fragmentation increases,habitat quality decreases significantly.The changes in habitat quality from 1995 to 2010 were mainly reflected in the vicinity of the lake,including the urban areas of Yueyang City,Huarong County,Yuanjiang City,Nan County,and Xiangyin County.The changes in habitat quality from 2010 to 2018 were reflected in the cities and towns around the county.(5)Dealing with the relationship between the"three-generation space",implementing strict wetland protection measures,and promoting the ecological protection and economic high-quality development of the lake area are the only ways to improve the habitat quality of the Dongting Lake area.