| During the last century, the ecological function and natural carrying capacity ofnatural ecosystem are ignored by human beings. The unreasonable over exploitationof natural resource has caused numerous ecological environment problems. Especiallyin arid area which located in a fragile belt of the ecosystem, the ecologicalenvironment problems are not only threatening the survival environment of humanbeings, but also affecting the development of human economy through upsetting thebalance of ecosystem and affecting energy and material circulation processes. One ofthe prominent environment problems is global warming. In2007, IPCC reported thatthe average global temperature has increased0.76℃since20th Century[1], and maykeep on increasing in the future. The main factor contributed to global warming is theincreasing emission of greenhouse gases from fossil fuel. Meanwhile anotherimportant factor is deforestation. As a vital carbon sink, forest vegetation absorbsCO2in atmosphere through photosynthesis. Due to carbon stock of forest ecosystemaccounting for82.5%of terrestrial carbon stock, the strong sink function of forestecosystem has attracted many attentions of science and politics. Simultaneously,Kyoto Protocol appealed every country to investigate the carbon sink function offorest and to reduce the emission of greenhouse gases via reforestation. Hence, areliable and accurate estimation of carbon stock of forest is meaningful for globalcarbon cycle research, and it also helps to reduce the uncertainty of estimation ofregional carbon budget.Qilian Mountaines located at the upper-bound of three important inland riverbasins in northwest part of our nation. Heihe River is the second largest inland river inour nation's arid and semiarid regions, the resource of water in the river basin is thekey guarantee for the ecosystem balance and the life headspring for the growth of theoasis. But with the huge increase of population, expand of the economics andunreasonable exploitation of the water resource has induced the deforestation anddesertification, further additional, the living and production of people has beenthreatened. The Party and nations has pay attention to the problem of ecology and environment in Heihe River, how to stop the procedures of the deforestation and torealize the sustainable development of the regional economics are the importantproblems that need to be quickly solved. In recent years, along with the fast increasingof the population and development of the urbanization, the limited water resource ofthe river basin undertakes the unlimited utilization and exploitation, as a result, theshortage of the water resource, the deterioration of the ecosystem at lower reach,shrinking of the oasis and growing of the desertification are inevitable, moreover,these trends are more and more serious, causes the more serious problem of abovementioned deteriorations.This research first interpolated the environmental variables which includeprecipitation and temperature with the help of spatial interpolation, then the charactersof spatial distribution these environmental variables were analyzed, based on therelationship between species and environment, I use these environmental variablesand the Border Function method to defined the ecological niche of study species,furthermore, the potential distribution of Qinghai spruce (Picea crassifolia) wasdelineated, based on these works, with the help of actual distribution of Qinghaispruce and field survey data, the characters of spatial distribution of Qinghai spruce'sbiomass was estimated. Finally, for the ecological construction and sustainabledevelopment of Qilian Mountains National Nature Reserve, some suggestions wereposed. The main results of this research include:(1) An elevational decrease trend of the mean annual temperature at QilianMountains National Nature Reserve can be detected; the latitudinal zonality is notobvious. With the impact of the latitudinal zonality and elevation, the mean annualtemperature has a trend of decreasing from southeast to northwest, the value of themean annual temperature ranges from-1.66℃~7.62℃, the maximum of this variableemerged at Dongdashan and Longshoushan, the minimum appeared at Qifeng,Longchanghe and high elevation area of Sidalong; the mean temperature of January atQilian Mountains National Nature Reserve displayed a clear elevational trend fromnortheast to southwest, in addition, another trend from east to west can be detected; value of the mean temperature of January ranges from-15℃~-7.55℃, the maximumof this variable emerged at Changlingshan, Hualong of Xiama and the east ofGucheng, the minimum appeared at Qifeng, Longchanghe and high elevation area ofSidalong; rate of elevational decrease trend of mean annual temperature at QilianMountains National Nature Reserve is more obvious than the trend of mean annualtemperature and mean temperature of January, the variation trend of July meantemperature from west to east is not very clear. Value of the mean temperature of Julyranges from11℃~21.58℃, the maximum of this variable emerged at Dongdashan,Longshoushan and Changshanling, the minimum appears at Qifeng, Longchanghe,Matisi and and high elevation area of Dahekou.(2) Comparison between the potential and actual distribution of Qinghai spruceshowed that the both potential and actual distribution of Qinghai spruce are similar atwest part of study area, demonstrated that the environmental condition is not suitablefor the growth of Qinghai spruce. At middle part of Qilian Mountains National NatureReserve, such as Sunan, Minle County of Zhangye and Qilian County of QinghaiProvince, the actual distribution of target species is prosperous; the potentialdistribution is equal to the actual distribution. Especially, at middle part of QilianMountains National Nature Reserve, such as, Xinchengzi, Maying, Damaying, Fengle,etc, the environmental condition is highly suitable for the growth of Qinghai spruce,the modeling result shows that the distribution displays a sporadic pattern, but thestrong disturbance of human activities have changed the suitable area to other land usearea, so the actual distribution area is smaller than potential distribution. The1kmresolution resample of the potential distribution area demonstrated that the potentialdistribution area covers6664pixels, which proved that the Qinghai spruce forest hasbeen severely disturbed. The distribution of study species may increase with suitableprotection and restoration activities.(3) The total biomass of Qinghai spruce is3.4×10~7t. The spatial distribution ofbiomass is influenced by geographic position and elevation, the biomass increase3.12t/hm~2when longitude increase1°, the biomass increase0.052t/hm~2when elevation increase100m, biomass increase3.8t/hm~2when latitude increase1°.(4) The carbon stock in real distribution area ranges from70.4t/hm~2to131.1t/hm~2, while mean value is109.8t/hm~2and total value is1.8×10~7t. The carbon stockin potential distribution area ranges from172.3t/hm~2to197.7t/hm~2, while meanvalue is187.7t/hm~2and total value is4.199×10~7t. There are75.8%,65.8%,59.5%and49.9%improved potential of carbon stock in western area, middle-west area,middle-east area and eastern area, respectively.
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