Study On The Change Of Landscape Pattern Of The Giant Panda Habitat In Fengtongzhai Based On RS

Fengtongzhai national nature reserve, a place of finding the first Giant Panda in the world, is one of an important nature reserves for protecting wild giant panda. The natural environment of Fengtongzhai nature reserve had been changing for more than thirty years since establishment of the nature reserve in1975. It seems to be necessary to investigate and study whether the giant panda living environment had changed, and what the direction and process of change. The remote sensing imagines in1975,1994and2009were used as information source in this paper. Based on the ERDAS IMAGINE9.2、ARCGIS9.3software, the human-computer interaction interpretation had been worked on the imagines of three periods. At last, landscape pattern index was calculated by software of Fragstats3.3, and the change of landscape in the study area in34years had been analyzed for the in this paper. The results indicated as follows:(1)Forestland, grassland and unused land was the main landscape type in study area, which accounted for72.19%,、9.99%and14.22%of the total area respectively, indicating that the forestland was acted as landscape matrix. While cultivated land, waters, resident land and mining land was relatively small, less than2%of total area. There was difference in space distribution characteristics of landscape types. The forestland type was mainly distributed in east, south and west area of study area. The grassland was distributed in north area. Cultivated land and resident land was mainly situated in lower-lying river valley regions of Baoxing east river and its branch. Mining land was mainly distributed in the central of the study area, which near to Guobayan area. The unused land was distributed dispersedly, without obvious distribution characteristic.(2) The analysis results showed that the space distribution of landscape types was closed related with elevation and slope factor. Mass of cultivated land and resident land concentrated distributed in river valley where elevation was below2000meters, with slope less10°. The main reason was that such place was benefit for humans’activity in the study area. The forestland type was mainly distributed in such regions that the range elevation was from2000to4000meters, slope of10～60°. The grassland and unused land was distributed above4000meters, with slope above60°.(3) During the period of34years, area of forestland, grassland and the unused land, in a word, was decreased, about1.62%、6.78%and2.61%respectively. Cultivated land and resident land, waters and mining land was totally increased, of which waters and mining land increased most, about3times and68times.(4) Analysis of landscape index showed that landscape pattern in the study area varied significantly. As a whole, the fragmentation level of landscape was decreased, while spread level and diversity of landscape was increased little. From1975to2009, the total number of patch in landscape was reduced by9.08%, value of CONTAG increased by1.09, and value of SHDI increased by0.72. Landscape pattern varied different in different study period. From1975to1994, the value of CONTAG increased from59.82to67.02, but SHDI decreased from1.141.05, showing the connectivity level of forestland patch was raised, with dominant position of forestland. From1994to2009, the value of CONTAG decreased from67.02to60.91, but SHDI increased to1.09, showing the connectivity level of forestland patch was weaked, with less dominance of forestland.(5) From1975to2009, forestland in road, mining district, hydropower stations’ buffer zones was reduced by3.72%、3.84%and9.07%respectively, which exceed the decrease range of forestland, which was1.62%. The increase range in NP, PD SHDI and SHEI index of buffer zones was larger than the amplitude of variation in whole study area, manifesting human activity such as paving road, building hydropower stations and exploiting mine did large damage to landscape pattern.(6) Connectivity level in giant panda’s migration channel,in total,was declined, presenting characteristic of aggravating. Connectivity level change in different periods was different. From1975to2009, the Cohesion of giant panda’s migration channel increased from97.4to99.1, while decreased to94.9from99.1during the period of1994to2009. The main reason causing the increase of connectivity level in giant panda’s migration channel was due to the found of nature reserve, which leaded to recover of vegetation. While that decrease of connectivity level in giant panda’s migration channel was caused by the Wenchuan earthquake, which triggered landslide and destroyed the forestland and grassland in migration channel.