干旱区生态环境知识资源中心

Due to the high altitude of over 4000 m, scattered inhabitation, and prevalent pastoral system, Tibet (Xizang Autonomous Region) is regarded as a unique geographic zone, possessing the most abundant solar energy resources in China. Due to the extensive use of conventional energy, significant ecological problems, including deforestation, soil erosion, land degradation, and desertification, have emerged and are becoming more severe; it is proposed that these issues can be mitigated by the utilization of solar energy. Consequently, studying the ecological effects of solar energy development in Tibet is of substantial significance. Accordingly, the resources, current situation, and potential of solar energy in Tibet were examined, and a framework for analysis to support appraisal of ecological effects was formulated. On the basis of this framework, the carbon effect, vegetation effect, and nitrogen effect were identified as the dominant ecological effects of developing solar energy in Tibet. The methodology to calculate and evaluate these ecological effects was then established and applied for our appraisal. The main conclusions are as follows: (1) based on the development scale of solar energy in 2008, the reduction of carbon emissions reached 539,100 tons, and the mitigation of carbon sink losses equaled 432,900 tons; (2) the large-scale utilization of solar energy can replace a large amount of conventional bioenergy sources such as fuelwood, dung, straw, and grass, resulting in reductions of forest destruction by 35.69 km(2) and grassland degradation by 77.23 km(2); and (3) with a reduction of nitrogen loss of 10,612.7 tons per year, the development of solar energy in Tibet also has an obvious nitrogen effect.