Study On The Giant Pandas’ Potential Habitat Based On “3S” Technology

As the symbol of China, the endangered species and world-class protected animal, giant panda has always been the object that is focused by world scientific research. The number of giant pandas in Sichuan Province takes up over 70% of the world wild pandas, while Pingwu County in Sichuan Province is honored as the first county of world pandas. The core research area Xiaohegou Nature Reserve in the article is located in Pingwu County. Around it lies the Songpan Huanglong and Songpan Longdishui nature reserves, and Wanglang and Xuebaoding national preserves. These nature reserves primarily protect giant pandas and their ecological systems. They also provide the basis for studying the species. Furthermore, this sample is comprised of a full giant panda protection system in the Minshan Mountains. Meanwhile, this area is representative of biological community types and acts as a very important geographical location. This location also appears to be an important transition zone between panda species A and B. The area belongs to the Himalayan-Hengduan Mountains, one of the core global biodiversity areas. The reserve maintains typical natural ecological systems and this one in particular is the most intact ecosystem within its latitude region. It has representation and typicality that is outstanding on a global scale.According to official published data(The 4th survey report on Giant Panda in Sichuan Province), there are altogether 49 pandas in Xiaohegou Nature Reserve at present and the area of protection zone is 282 sq.km. According to the understanding to the survival habitat of panda in previous research results, the single panda’s territory area is about 7 sq.km, considering that there are large stretches of bushwood and grassland, scree, sparse vegetation and other areas that are not suitable for the long-term survival of panda, it has caused the saturation and slight over capacity in Xiaohegou Nature Reserve(only 4.77 km2 for one to live).Therefore, the expansion of protection zone is brought to the schedule and the scientific problem how to reasonably and effectively expand the protection zone is put forward. With ecology, geography, remote sensing spectroscopy and multi-subject knowledge as support, ―3S‖ technology is used to systematically analyze the extension of the protected areas under a population number increasing condition, established Xiaohegou giant panda nature reserve expansion prediction method model and extraction model of Remote sense information of the giant panda nature reserve. Complete the discrimination and forecasting of the potential habitat of Xiaohegou nature reserve of Pingwu, delimitate the extension scope of the Xiaohegou nature reserve, and forms forecasting methodology of the expansion of a giant panda nature reserve. And the main conclusions are:(1)The tree species with the highest use ratio for giant panda habitat in the protection zone are theropencedrymion and coniferous forests, in which, coniferous forests, the main habitat for giant pandas have been reduced by 13.0581 km2 during 1994-1998, with annual average deterioration rate of 2.61162 km2/year; during 1999-2014, 5.9382 km2 was recovered, with annual average recovery rate of 0.39588 km2/year; Forest destruction before 1998 so obviously, but benefit from the implementation of natural forest protection project,according to the present natural recovery rate, it will take 18 years to restore to the area level in 1994.(2)The ecological niche model of space, ecological niche model of remote sensing inversion(master environment), ecological niche model of soil and ecological niche model of geochemistry(heavy metal) disturbance have been established in Pingwu County giant panda habitat. Through analysis of above models, the main conclusions are as follows:1) Through the analysis of ecological niche model of space, the orientations that giant pandas in Xiaohegou Nature Reserve tend to select are north, northeast, east, southeast and south; while the tendency of southwest, northwest and west is poor;It is known that the maximum gradient value for giant panda to survive is about 37 o and the most suitable altitude for the survival of giant panda is about 2300-3300 m in this area. In addition, pandas tend to select the area with solar irradiance higher than 1.6×106 WH/m2.2) Through the analysis of Remote sensing retrieval ecological niche model(master environment), it can be known that the most suitable reproductive humidity is about 80%(spring and summer). While in winter, it has the lowest humidity requirement. The whole-year humidity requirement is about 40%-80%. The giant panda’s requirement to annual precipitation in this nature reserve is about 920 mm, which basically keeps stable. The demands for the suitability of temperatures of giant pandas from high to low are summer, autumn, spring and winter respectively in the nature reserve. the optimum canopy density value in the nature reserve is about 60%, which is basically consistent with previous research.3) Through the analysis of ecological niche model of soil, it can be known that the most suitable soils are dark brown earth and brown soil. The habitat soil mainly indirectly affects the distributions of giant pandas through the growth state of staple food bamboos. When the content of the coarse soil in the habitat is 8%, the habitat is most suitable for giant pandas; when the coarse sand content in the soil reaches 30%, the soil environment is no longer suitable for panda to survive. When the fine sand content is 12%, it is most suitable for giant panda to survive; when the fine sand content reaches 46%, the soil environment is not suitable for panda to survive. When the silt content is 37%, it is most suitable for giant panda to survive; when the silt content exceeds 54%, it is not suitable for giant panda to survive. When the potassium element content is 3.2%(optimum), nitrogen content is 0.43%, it is most suitable for giant panda to survive. The optimum value of phosphorus content in the soil is 0.08%. When the organic matter content in the soil is 11%, it is most favorable for panda to survive.4) Through the analysis of ecological niche model of heavy metal, the results show that: Cr has the largest influence to giant panda habitat. The maximum Hg bearing value in the habitat soil is 70×10-6 mg/kg.The maximum Hg bearing value in the habitat soil is 462.8×10-9 mg/kg and the maximum Pb bearing value is 37.94×10-6 mg/kg. If the above values of heavy metal elements exceed the calibration values, the encounter rate of giant pandas in the regionis dropped to zero.(3)Overlay the environmental suitability model and edaphic factor suitability model result of main influencing factors through fuzzy overlay method. Taking overall consideration of the model result of the spatial ecological niche, the model result of the heavy metal ecological nichel and form factor, water source distance, geological-hazard-prone area(point), farmland disturbance, etc., it has concluded the final expansion scope of Xiaohegou Natural Reserve and the size is about 575 sq. km. The extension part is mainly from the east part of the protected area to the nine ring direction of the Baima Tibetan village and a small amount of the expansion areas also exist in other directions and other adjacent areas of the protected area.The expansion direction can not only satisfy the reproduction and stability of giant panda population in the zone, but it also has avoided the disturbance to local economic development.