Analysis Of Landscape Pattern Change And Ecological Carrying Capacity Of Dongting Lake Area In Recent 20 Years

In this paper,the landscape indexesof landscape pattern in Dongting Lake area,such as the number of patches(NP),patch density(PD),edge density(ED),the largest patch index(LPI),landscape shape index(LSI),Shannon plaque index(SHDI),mean patch fractal dimension(FRAC_MN),have been analyzed by remote sensing image in 1996,2001,2005,2012,2016.Then,the ecological carrying capacity of the area was studied usingthe ecological footprint method.Finally,the response relationship between landscape pattern change and ecological carrying capacity was analyzed by SPSS software.The main conclusions are as follows:(1)Landscape pattern change in Dongting Lake area:from 1996 to 2016,the cultivated land area was on the rise;there was a small increase in forest land area from 1996 to 2005 and from 2012 to 2016,but the decline from 2005 to 2012;the grassland showed a decreasing trend in the past 20 years,especially,there was the biggest change from 2012 to 2016;water area was decreasing year by year from 1996 to 2012,but it was increasing from 2012 to2016;the construction area showed an upward trend during these 20 years,especially from1996 to 2001 and 2005 to 2012;while other land generally showed a downward trend,and the downward trend was faster and faster.Furthermore,the overall landscape fragmentation was on the rise;the mean fractal dimension increased and the shape was more complex;the heterogeneity was decreasing,the diversity was increasing,and the degree of stability was rising.(2)Based on the method of ecological footprint on ecological capacity,compared to those in 1996,it can be seen that the per capita ecological carrying capacity in woodland,grassland and water of Dongting Lake area in 2016 was decreased,but per capita ecological carrying capacity of cultivated land was slightly increased,and construction land showed a large rise.In 1996 and 2016,ecological deficits were 0.437 hm~2 and 1.125 hm~2per capitarespectively,also,ecological deficit greatly increase from 1996 to 2016 in Dongting Lake.Especially,the amplification of per capita ecological deficit of energy land was the highest,from 0.229 hm~2 in 1996 to 0.518 hm~2 in 2016,which has exceeded the range of ecological carrying capacity.Theresultsindicated that,owing to human production and life,the pressure of ecological system in Dongting Lake area is rising.(3)The correlation between landscape pattern and ecological carrying capacity(EC)was analyzed by the SPSS software.EC was positively correlated with the LPI and FRAC_MN with a statistical significance,and the correlation coefficients were 0.879 and 0.881,respectively.Meanwhile,EC has a negativelycorrelation with SHDI with a statistical significance,and the correlation coefficient was as high as 0.993.Thus,there is a significant correlation between EC and the degree of fragmentation of the landscape.