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331.
The article studies tourism eco-environment of 14 cities of Gangsu Province, China, based on GIS with many kinds of multi-subject spatial database, such as remote sensing data, observation data and literature data. The research results were as follows. First, spatial features of 14 cities' tourism eco-environment are displayed with five levels of vulnerability respectively. The vulnerability in Gansu becomes worse from Gannan City, located in southern Gansu to Hexi Corridor which lies in northwestern Gansu. Second, the areas of above the middle vulnerability level make up 75% of the total areas of Gansu Province. Third, more than 70% of high-level human and natural tourism resources are in the areas with high vulnerability eco-environment. Fourth, it is crucial to develop comprehensive tourism industry in order to improve the harmonious development between tourism industry and eco-environment in Gansu Province.  相似文献   
332.
China has witnessed rapid economic development since 1978, and during the time, energy production and consumption developed at a tremendous speed as well. Energy efficiency which can be measured by energy consumption per unit of GDP, however, experienced continuous decrease. Theoretically, the change of energy efficiency can be attributed to industry structural change and technological change. In order to explain the transformation of Chinese energy efficiency, we adopt logarithmic mean Divisia index techniques to decompose changes in energy intensity in the period of 1994-2005. We find that technological change is the dominant contributor in the decline of energy intensity, but the contribution has declined since 2001. The change in industry structure has decreased the energy intensity before 1998, but raised the intensity after 1998. Decomposed technological effects for all sectors indicate that technological progresses in high energy consuming industries such as raw chemical materials and chemical products, smelting and pressing of ferrous metals, manufacture of non-metallic mineral products and household contribute are the principal drivers of China's declining energy intensity.  相似文献   
333.
Household consumption is one of the important factors that induce COL emission. Based on input-output model, this article calculated the intensity of CO2 emission of different income groups and seven provinces in China, and then estimated total CO2 emission induced by urban household consumption from 1995 to 2004 in China based on statistic data of household living expenditure. The results show that CO2 emission per capita induced by household consumption had increased from 1583 to 2498 kg CO2 during 1995-2004. The ratio of consumption-induced CO2 emission to total CO2 emission had risen from 19% to 30% in the past decade. Indirect CO2 emission accounted for an important part of the consumption-induced emission, the ratio of indirect emission to consumption-induced emission had risen from 69% to 79% during the same period. A significant difference in consumption-induced CO2 emission across different income groups and different regions has been observed. COs emission per capita of higher income groups and developed regions increased faster than that of lower income groups and developing regions. Changing lifestyle has driven significant increase in CO2 emission. Especially, increases in private transport expenditure (for example, vehicle expenditure) and house building expenditure are key driving factors of growth in consumption-induced COL emission. There are big differences in the amount of CO2 emission induced by change in lifestyle across different income groups and provinces. It can be expected that lower income households and developing regions will increase consumption to improve their livings with income growth in the future, which may induce much more CO2 emission. A reasonable level of CO2 emission is necessary to satisfy human needs and to improve living standard, but a noticeable fact is that CO2 emission per capita induced by household consumption in developed areas of China had reached a quite high level. Adjustment in lifestyle towards a low-carbon society is in urgent need.  相似文献   
334.
The establishment and development of the industrial symbiosis of eco-industrial park are affected by several factors. Based on the formed industrial symbiosis supporting system chart, this article analyzes the microcosmic supporting system and macroscopic supporting system. In the microcosmic supporting system, it elaborates five aspects including key enterprises, service intermediaries in the park, symbiotic enterprises, competitors and the public in detail. Then it describes the macroscopic supporting system from four aspects of governmental participation, technological innovation, educational promotion and cultural support. Finally, combining with the current construction status of the ecoindustrial park in China, it proposes the countermeasures and suggestions to build the supporting system for the eco-industrial park and provides theoretical support for the faster and better construction of the eco-industrial park in China.  相似文献   
335.
在WRF模式中选取不同的陆面过程、边界层以及近地面层参数化方案,设计了6种不同的参数化方案组合,模拟江西省某高山风电场测风塔2016年1月和2017年1月逐时风速、风向,并与同期实测数据进行比较,选出MRF边界层参数、WSM3微物理过程参数和Noah陆面过程参数作为最优参数化组合方案。对最优参数化组合方案的模拟结果进行整一年的逐时模拟效果检验,结果表明:最优参数化组合方案对全年风速模拟效果较好,模拟结果风速日变化趋势及风速段(0~24时)分布与实测基本一致,模拟的风速峰值及概率偏大,主要是由于模式的精度不足以准确描述山地风场复杂下垫面造成的。模式最优参数化方案对风向模拟与实测主导风向分布一致且风向频率相似  相似文献   
336.
Species turnover patterns can be inconsistent due to differences in the dispersal ability of different growth forms. Here, species of trees, shrubs, herbs, and bryophytes in the Xiaoqinling National Nature Reserve in China were analyzed to determine patterns of species turnover along an elevation and spatial gradient. Variance partitioning was used to assess the relative contribution of topographic heterogeneity and dispersal limitation to species turnover. Our results suggest that the effect of dispersal limitation is more important than topographic heterogeneity on species turnover in temperate mountane ecosystems in the study area. Dispersal limitation has a greater effect on trees species turnover than on shrubs, herbs or bryophytes species turnover.  相似文献   
337.
Under the current situation of environmental pollution and resources shortage, the research of corporate environmental responsibility (CER) is of great importance to promote the sustainable development of society. The article adopts the perspective of the Stakeholder Theory and environmental management to make the empirical analysis of CER. Consequently designed questionnaire investigation is carried out among 30 Shanghai enterprises during 2007 and 2008. Through the correlation analysis, principal component analysis, factor ordering, and variables reappearance of key factors, seven key indexes are identified in the original 35 variables. This article aims to provide reference for enterprise environmental management and forwards the study of Corporate Social Responsibility.  相似文献   
338.
Several natural and anthropogenic radionuclides (210Pb, 226Ra and 137Cs) in guano-phosphatic coral sediments and pure guano particles collected from Ganquan, Guangjin, Jinqing and Jinyin Islands of the Xisha archipelago, South China Sea, were analyzed. The Constant Initial Concentration (CIC) model and the Constant Rate of Supply (CRS) model were applied for age calculation. The average supply rate of 210Pb was 126 Bq m−2 a−1, very close to the flux of northern hemisphere average (125 Bq m−2 a−1). The activities of anthropogenic radionuclides in the sediments were very low, indicating that human nuclear tests did not notably impact this region. The main source of radionuclides in the sediments was from atmospheric precipitation, and the organic matter derived from plant and produced by nutrient-rich guano could further enhance them.  相似文献   
339.
This paper discusses the basic concept and connotation of population modernization. The author briefly analyzes the actuality of population modernization in China, gives some advice and puts forward some measures.  相似文献   
340.
A pot experiment was conducted to investigate the influence of citric and oxalic acids effect on Pb and Zn uptake by corn and winter wheat. The experiment was employed with citric acid (CA) applied at 3 rates (0, 1.5 and 3.0 mmol kg-1 soil), oxalic acid (OA) at 3 rates (0, 1.5 and 3.0mmol kg-1 soil) and citric acid combined with oxalic acid (1.5 mmol citric acid combined with 1.5 mmol oxalic acid kg-1). Two types of soil were chose in the experiment. One was collected from the agricultural soil near a battery-recycling factory in Anhui province, China (site A) and the other was collected from a Pb-Zn mine residues in Hunan province, China (site B). The results showed that soil pH varied with the different treatment of citric and oxalic acids. However, there were no differences in all the treatments. 3.0mmol CA kg-1 soil addition significantly increased the concentrations of the CaCI2-extractable Pb and Zn and other treatments have no significantly increased. The highest shoot concentrations of Pb and Zn  相似文献   
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