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Economic and population growth in Asia over the last three decades has been unprecedented. While conventional economic indicators have been increasing consistently, indicators of resource and environmental quality have been deteriorating, raising questions about the implications of future growth. Economic growth in the future is considered to be contingent on ensuring a more efficient use of natural resources, while simultaneously striving to reduce environmental impacts. We examine time trends of three efficiency indicators; agricultural efficiency, energy efficiency of economic production and carbon efficiency of energy use, for the five most populous countries in Asia in order to assess whether industrial development has lead to increased resource use efficiency and an associated reduction in total resource use and environmental impacts. Our results indicate that agricultural efficiency has decreased in all five countries. Results are mixed for energy and carbon efficiencies. Where increases in energy and carbon efficiency have occurred, they have been completely overwhelmed by absolute increases in energy use and carbon emissions caused by increases in the scale of economic activity. Based on this analysis, we study the potential for further improvements and policy implications for future food supply, energy consumption and carbon emissions in the region. 相似文献
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中国能源政策的大气污染物减排效果与附加效应--上海案例研究 总被引:2,自引:0,他引:2
为了研究中国能源政策对减少本地大气污染物排放的效果,以及减缓二氧化碳排放增长速度的附加效应,以上海为例,采用MARKAL模型对基础情景和能源政策情景下的能源消费及大气污染物排放量进行了预测,并分析了能源环境政策减缓二氧化碳排放增长的附加效应。结果显示,实施能源政策后,上海市的SO_2、PM_(10)。排放量均有大幅度降低,并可明显减缓CO_2排放的增长速度。2000~2020年,SO_2排放量将基本保持在2000年的水平,CO_2排放总量的年均增长率将由基础情景下的2.7%减小到能源政策情景下的1.1%~1.2%。 相似文献
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Masae Shiyomi Tsuyoshi AkiyamaShiping Wang YiruhanAilikun Yoshimichi HoriZuozhong Chen Taisuke YasudaKensuke Kawamura Yasuo Yamamura 《Ecological modelling》2011,222(13):2073-2083
The natural grassland ecosystem of the Xilingol steppe has traditionally been the source of the most productive and highest quality agriculture in northern China. Unfortunately, the area is now experiencing degradation due to resource overuse. In an attempt to forecast grassland production and to sustain the ecosystem, we built a time-dependent simulation model of the ecosystem based on long-range weather forecasts (several weeks to several months). The model incorporated five state variables including above- and belowground biomass, the amount of standing dead plant material, livestock (sheep) weight, and the amount of excrement per unit ground area. Within the model, solar light energy is fixed by grassland vegetation and flows through the other variables via a variety of organism-environment interactions. The model was written using a set of simultaneous differential equations and was numerically analyzed. The values of the time-dependent parameters controlling energy flow were determined based on data accumulated in experiments and field surveys executed at a grassland experimental station located in Xilingol, as well as by reference to related literature. We used daily meteorological data including air temperature and rainfall recorded at the Xilinhot Meteorological Observatory. Simulated results for several stocking densities coincided well with the data of aboveground plant biomass observed at the experimental station in 1990, 1993, and 1997. We obtained reasonable simulation results for five stocking densities, three air temperature patterns, and five rainfall patterns. When a month-long drought, which sometimes occurs in this area, was forecast by a local weather station, a decrease in grassland production was forecast by the model. Such forecasts will assist in the management of livestock, forage preservation, and grassland conservation. 相似文献
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Rui Yue Zhikang Chen Liujun Liu Lipu Yin Yicheng Qiu Xianhui Wang Zhicheng Wang Xuhui Mao 《Frontiers of Environmental Science & Engineering》2022,16(11):147
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