Ecological Environmental Quality Assessment Of Shigatse On 3S

This paper reports the environment condition of the Shigatse.All the environment parts of Shigatse were regard as the study area.According to validating in the field and using GIS technology,also with the support of LC8 remote sensing images data in 2015,the database of local land use space structure was established.In order to calculate the urban landscape pattern index,we determined to choose all the 18 counties(cites)of Shigatse as evaluation units.Based on this purpose,the remote sensing data and relevant statistical data were analyzed to calculate all kinds of monitoring index of study area,such as the vegetation coverage index and ecological threat index.Besides,the biological abundance index and water network density index were also included in the whole evaluate system.The ecological environment index(EI)value which can estimate the environment condition of study area was calculated by using this evaluate system and each weight of the monitoring index.This prospective study was performed to make suggestions to local ecological environment problems.Through discussions and analysis,this paper reached the following conclusions:(1)The interpretation accuracy of land use structure was reached to 87.5% by using this researching method.Also the high distinct picture quality of LC8 remote sensing image reflected the regional state of topography and the condition land use structure clearly.As for the best phase to interpretation all the remote sensing data of Shigatse was July to August.(2)The total interpretation area of study area(Shigatse)178700 km2 in 2015,and the number of remote sensing interpretation chart was 26541.According to the analysis of all kinds of land use structure in the study area,it was found that: considering all kinds of structures,land-grass is the largest one,which covered 86099.79 km2,about 48.18% of the total area of the district;The second is unused part,covered 68066.24 km2,accounted for 38.09%;The third one was the water district,covered an area of 12058.28 km2,accounting for 6.75%;In turn is forest,the area of 9479.84 km2,accounting for 5.30%;Cultivated land area of 2347.83 km2,accounting for 1.31%;The smallest of the construction land was the urban and rural residents,industrial and mining etc,only covered 664.85 km2,accounted for only 0.37% of the total area.(3)The district of high EI index area were concentrated in the west,central and northwestern region.Such as the Nan Mulin County,La Zi area,Jiang Zibu County,Rinbung County,Gyantse County,Yadong County,Jilong Country,Bainang County,etc.Lower parts were concentrated on north and south County,Kangba,SaGa County,Tingri County,GangBa County,Kangmar County.As for the reason of lower EI index,mainly due to the regional population is relatively concentrated,low altitude and poor environment condition.Considering the EI index of all the evaluate units,the highest one is Yadong County,which EI index is 49.14,and the lowest is GangBa County,31.28.(4)In this paper,with the aid of remote sensing image data,GIS and GPS technology,the combination of quantitative and qualitative analysis of the ecological environment of Shigatse,all the evaluation parameters were obtained conveniently,research method has also certain feasibility and operability,the evaluation results were reflected the actual ecological situation more realistic.