Study On The Coupling Relationship Between Giant Panda Spatial Distribution And Eco-geological Environment

The giant panda(Ailuropoda melanoleuca)is the national treasure of China and the ancient relict,and the flagship species of the globle wildlife and biodiversity conservation.It has long received high attention from all walks of life around the world.The giant pandas in Sichuan province live on the eastern edge of the Qinghai-Tibet Plateau,which is a transition zone from the Qinghai-Tibet Plateau to the Sichuan Basin.The complex natural environmental conditions have created good preservation conditions for giant pandas and other ancient animals and plants.Due to the uplift of the Qinghai-Tibet Plateau,the Quaternary climate change,and the development of human society and economy,the habitat of wild giant pandas has shrunk sharply,and the population has declined.However,due to the uplift of the Qinghai-Tibet Plateau,violent neotectonic movement and ancient broken stratum lithology,earthquakes and secondary disasters occur frequently,and the ecological environment of the giant panda habitat is fragile.This area has great scientific research value and significance for studying the changes of the Quaternary geological environment and biological processes.The study selects the county area of the giant panda distribution area in Sichuan Province as the research area.Studying the coupling relationship between the spatial distribution pattern of giant pandas and the ecological geological environment of the giant panda habitat,and analyzing the mechanism of the impact of the ecological geological environment on the distribution of giant pandas,will provide scientific reference and decision guidance for the protection of the giant panda and its habitat.It has important scientific and practical value and theoretical significance for activities such as enriching and enhancing the giant panda national park,the construction of giant panda corridors,and the reintroduction of captive giant pandas in the wild.Therefore,this study is guided by the concepts of earth system science and geoinformation science,based on ecogeology,tectonic geomorphology,environmental geochemistry and other multidisciplinary theories,based on the systematic collection and summary of previous research results and field surveys.Comprehensive application of system theory,the principle of maximum information entropy and the principle of niche,with the"3S"technology's spatial analysis,geospatial database and digital mapping techniques,as well as mathematical modeling and numerical simulation and other quantitative analysis methods,the study screened and determined the optimal scale for the study of giant pandas and their habitats,constructed the eco-geological environment system model and index system of the giant panda habitat,explored the restriction of the geological background on the distribution pattern of giant pandas and staple food bamboo,and predicted the potential spatial distribution of giant pandas and assess the habitat suitability.The main results obtained through the research are as follows:(1)The theory of eco-geological environment system and factor coupling relationship model of giant panda habitat are proposed.The giant panda habitat eco-geological environment system is the"atmosphere,geosphere,biosphere and anthroposphere"holographic huge disequilibrium system,which can be divided into four types of influencing factors:climate(atmosphere),geological background(geosphere),organism(biosphere),and anthropogenic(anthroposphere)factors.climate(atmosphere),geological background(geosphere),organism(biosphere),and anthropogenic(anthroposphere)."Atmosphere"refers to atmospheric factors or climatic environment,mainly including conditions such as precipitation and temperature;"geosphere"refers to the underground environment dominated by the surface layer of the earth's crust(weathered crust),which mainly includes geological structure,topography,and rock conditions such as minerals,geochemistry,and ground hydrology;“biosphere”refers to organisms,mainly including giant pandas and their staple food bamboo,forest vegetation and competing animals,and other biological inter-species relationships;"anthroposphere"refers to is as the main aspect of human social and economic development,including environmental protection,biological protection,poaching poaching,deforestation,agriculture and animal husbandry industry,tourism industry,traffic and road construction and other aspects of regulation and interference.According to the factor coupling relationship model,using the information quantification methods,the climate factors includes temperature and precipitation factors(19 climatic indicators);the geological background factors includes macro-topographic factors(relief amplitude,surface incision,variance coefficient in elevation,roughness index),lithological factors(lithological diversity index),soil factors(soil diversity index),hydrological factors(river density)and geochemical element factors(Ca,Na,Fe,Cu,Cr,K,Mg,Mn,Zn,etc.);organism factors include giant panda factor(density of giant panda),staple food bamboo factor(staple food bamboo diversity index)and vegetation factor(vegetation diversity index);anthropogenic factor(road density).(2)The global spatial autocorrelation Moran index was used to screen the optimal grid size,and the giant panda habitat eco-geological environment system geospatial database was established.Research shows that under the condition of 10km×10km sampling scale,the diversity(richness)of staple food bamboo in giant panda habitat has significant aggregation and scale dependence,which can better reflect the actual distribution of staple food bamboo diversity in giant panda habitat.It is the optimal scale for the study on giant pandas,staple food bamboo and their habitats.According to the optimal scale,the giant panda habitat eco-geological environment system geospatial database was established,including 5 categories of data,11 datasets and 40types of data,with a raster data resolution of 10km×10km.The results of data visual analysis show that the spatial distribution of giant pandas and staple food bamboo and habitat environmental factors in Sichuan Province is mainly distributed along the WN-ES direction,and the vertical gradient difference is very obvious,indicating that the geological background has an important restrictive effect on the distribution of giant pandas except due to anthropogenic activities and climatic factors.The study results show that the reason for the modern distribution pattern of giant pandas is the result of a combination of environmental factors such as the uplift of the Qinghai-Tibet Plateau,climate change during the Quaternary period,the relationship between biological species,and modern man-made activities.(3)To analyze the relationship between the environmental factors of the eco-geological environment system and the giant panda and its staple bamboo and its restrictive effects,the linear regression and multi-factor variance decomposition methods were used.The four environmental factors of“atmosphere,geosphere,biosphere and anthroposphere”selected in the study can better explain 55%of the overall variance of the distribution pattern of giant pandas,of which the comprehensive explanatory power of geological background(geosphere)and organism(biosphere)are28%respectively,42%is the unchangeable main controlling factor restricting the distribution of giant pandas and staple food bamboo;the comprehensive explanatory power of organism(biosphere)and anthropogenic(anthroposphere)are both 11%,although both are much smaller than the combined geological background factors and climatic factors However,it cannot be ignored in restricting the distribution pattern of giant pandas.It is a controllable factor that affects the distribution pattern of them.(4)To determine the optimal model for predicting the distribution of giant pandas,and evaluate the suitability of the giant panda's habitat,the stepwise regression and Akaike information criterion were used.The suitable area for the distribution of giant pandas in Sichuan Province totals 3,456,200 hm~2,of which Minshan Mountain(1,489,500 hm~2)>Qionglai Mountain(1,031,800 hm~2)>Liangshan Mountain(567,100hm~2)>Daxiangling Mountain(292,200 hm~2)>Xiaoxiangling Mountains(71,300hm~2)>Qinling(4,400 hm~2).The most suitable and suitable distribution areas are mainly concentrated in the central and northern part of the Minshan Mountains and Qionglai Mountains,while the Daxiangling,Xiaoxiangling,Liangshan and Qinling Mountains are only suitable areas,indicating that the Minshan and Qionglai Mountains have the best eco-geological environment.The Xiangling,Liangshan and Qinling Mountains(the part of Sichuan province)need to strengthen the protection of the ecological and geological environment.(4)The evaluation results of the relative importance of predictors show that the impact of the 3rd-level indicators from high to low is the seasonal coefficient of variation of precipitation(18.1%),staple food bamboo diversity index(14.6%),road density(10.1%),and annual average temperature(8.8%),annual precipitation(7.9%),topographic undulation(6.7%),lithology diversity index(5.6%),annual temperature range(5.4%),average altitude(5.2%),elevation variation coefficient(4.6%),iron oxide(4.2%),magnesium oxide(3%),vegetation diversity index(2.4%),magnesium oxide(1.6%),chromium oxide(1.5%),potassium oxide(0.3%);2nd-level indicators are precipitation factor(26%),macro topographic factor(16.5%),staple food bamboo factor(14.6%),temperature factor(14.2%),geochemical element factor(10.6%),anthropogenic activity factor(10.1%),lithology factor(5.6%)and vegetation factor(2.4%);1st-level indicators are climate factor(40.2%),geological background factor(32.7%),biological factor(17%)and human factor(10.1%).The study have shown that the degree of importance of the factors affecting the spatial distribution of the giant panda,the geological background,behind climate fatcor,inludes macro topographic factor,factor element geochemistry and lithology factor.