Coupling Relationship Between Ecological Environment Change And Quantity Fluctuation Of Relict Gulls In Hongjian Nur Wetland

The habitat of relict gulls in Hongjian nur is the ecological protection area in the world,from 2001,the number of relict gulls are increased continually,however,the area of lake which is closely linked to relict gull in Hongjian nur is reduced yearly,ascertaining the change of ecological environment of relict gull in Hongjian nur can contribute to analysing the reason why the number of relict gull increased,then taking action to provide the better theory basis for protecting relict gull ecological habitat.This text analysed the change characteristic of relict gulls,number and ecological environment,analysing the coupling relationship between the number of relict gull and habitat,ascertaining the reason of the area of lake in Hongjian nur decreased yearly,while the number of relict gull increased yearly in the habitat.On the basis of the number of relit gull breeding population,nests,ovipositions and squabs,through general analysis,ascertaining the rising situation of the number of relict gulls in these 10 years.In the characterization study of environmental change,taking three periods remote sensing image of 2001,the year of 2007 and 2011 in the study area as background data,using the method of conbination between remote sensing digital image processing and spatial analysis of GIS,extracting a single evaluation index of ecological environment,including vegetation coverage,water density index.biological abundance index,the index of human activity and soil erosion index,through principal component analysis intergrating eco-environmental evaluation indices to evaluate ecological environment in Hongjian nur protection area,finally on the base of the data after grading comprehensive ecological environment spatial distribution characteristics,utilizing diversion model to analyse the transfer situation in different ecological environment level and driving factor in 10 years.In addition,in order to ascertain the relationship between the increase in the number of relict gull and habitat change,extracting aromatic diversity index,landscape fragmentation index,area of various land use types and fragmentation index of 14 habitat factors in the study of 2001,2003,2007,2009 and 2011,using grey correlation model,analysing the relevancy between relict gull species populations and habitat factors,ascertaining sensitive factors of relict gull habitatThe results of the study are as follows:(1) The change of relict gull quantity indicates: the number of relict gulls present a fluctuated growth trend,while the growth trend of the number of the relict gull has a larger difference;The year of growth more obvious focused on 2002,2003,2007 and 2010,the number of relict gull and the species populations of relict gull grow quickly in 2002 and 2003,especially has a geometrical progression growth in 2003,from 551 in 2002 grow to 4012 strongly,the growth rate reach 628.13%.The main reason is that unreasonable tourism development in ordos lead to a serious destruction of relict gull in ecological area in this peroid,a large number of relict gull migrate to Hongjian nur.After 2003,the number of relict gull present a stable growth,except a negative growth in 2008 and 2011,the rest of the year all have a positive growth of the number of relict gull.Along with the growth of the number of relict gull,ovary and the number of eggs growth as well,the nests and ovipositions have a same volatility with the growth of the number of relict gull,the maximum appears in 2003.The egg hatching rate of relict gull present a fluctuated change,it has a low hatchability in 2001 and 2002,they are all below 90%,it maybe the number of relict gull is few before 2003,our country takes less protective measures in this region,and man-made destruction and hunting are more serious,result in the lower egg hatchability.After 2003,the government strengthen the protection of the protected area,the relict gull have a relatively safe habitat and breeding sites,then the hatching rate increased greatly,it maintains above 90% basically.(2)The analysis of three periods environmental variation characteristics indicate:The environment tend to get better from 2001 to 2007,while the environment become weak from 2007 to 2011.The drive factors of the ecological environment become better in Hongjian nur is the increase of vegetation coverage of the larger forest area,but the reason why ecological environment become deteriorate is that the frequently increase of building land and cultivated land area by human activity,especially in the round of Hongjian nur lake.From 2001 to 2007, due to the development of tourism and the increase of buildings and structures surround the lake,then the surface hardening and ecological environment become deteriorate;The area of ecological environment become better in some of the returning farmland to forest and grass, and planting more trees.The ecological environment change from 2007 to 2011,the increase of population lead to the increase of buildings and structures in study area,the cultivated land area and the production and living water increased dramatically result in the water area decreased year by year in Hongjian nur,and the ecological environment where along the river is damaged to a certain extent.In the three periods of ecological environment,one of the best is in 2007,it has a larger alignment with the variation of the number of relict gull during 10 years,thc number of relict gull is 10072 in 2007,which is maximum in these few years.After 2007,the number of relict gull is decreased,it is affected by the ecological environment become weak,and it indicates that there is a bigger relationship between ecological environment change and relict gull quantity change.(3)The coupling analysis of the number of relict gull and habitat sensitive factors indicate:from 2001 to 2011,In the environmental change of dry climateand man-made,and wetland area shrinking, the damage of wetland environment,the number of relict gull not only become fewer,but also growth steady,it is asensitive factor with the habitat change of relict gull.From the analysis of the coupling relationship between the number of relict gull and lake area where main relict gull habitat and wetland area,we can conclude:the lake area and wetland area decreased yearly.whlie the number of relict gull increased,it indicates that wetland area is a non-critical factor in the increase of the number of relict gull in these 10 years,it is a the necessary factor in the habitat survival of relict gull.The coupling relationship between 14 habitat factors and the number of relict gull indicate:Woodland area,grassland area,landscape diversity and landscape fragmentation are habitat sensitive factors of relict gull, and they are key factors in affecting the increase of relict gull year by year.The increase of woodland area in protection area provide a new habitat for relict gull;the large area of afforestation and returning farmland to forest and grass can reduce the sand area,under the condition of various types of landscape.it increased the landscape fragmentation greatly,and provide a new place for relict gull to activity for food; All kinds of ecological base protection measures are taken by the government,they improve the ecological environment of the whole protected area,and the improvement of relict gull habitat can maintain a stesdy breeding of relict gull in protected area;The egg hatchability of relict gull reduced yearly,it has a largest correlation coefficient with the residents to fragmentation,high correlation with landscape fragmentation and arable land,this mainly because of the tourism development in protected area and the increase of population,then deliberatly destruction of relict gull ovarian and kill small relict gull phenomenon appear constantly by human,and disorderly catching disorderly hunting,poaching phenomenon also happened occasionally,and the illegal activities making damage on relict gull lived;for this purpose.the ecological protection base should further intensify the building of ecological civilization of relict gull in yulin city,improving the protective mechanism of the relict gull,and providing a safe and comfortable habitat for relict gull and other various kinds of migratory birds.