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581.
方言  曹芳  范美益  章炎麟 《环境科学》2020,41(3):1025-1035
本研究于2017年12月至2018年2月以及2018年6~8月在嵊泗岛屿共采集70个大气总悬浮颗粒(TSP)样品,利用离子色谱法分析TSP样品中水溶性离子(主要包括:Na+、 K+、 NH+4、 Mg2+、 Ca2+、 Cl-、 SO42-、 NO-3和MSA)的质量浓度,结合HYSPLIT后向轨迹模型,离子相关性分析和主成分分析等方法,探讨东海背景站水溶性离子组分的化学特征、季节差异以及主要来源.结果显示,观测期间TSP和主要水溶性无机离子(WSIIs)质量浓度均表现为冬季高、夏季低,冬季和夏季的总水溶性离子(TWSIIs)平均质量浓度分别为(26.5±16.3)μg·m-3和(8.8±3.8)μg·m-3.二次离子(NO-3、 SO4<...  相似文献   
582.
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   
583.
中国台湾地区土壤及地下水污染整治基金管理会自2001年成立以来,不断完善管理架构和管理体系,发布相关领域的法律法规、行政规则和公告,有效运行污染整治基金的财务筹措和使用等经济管理机制。开展了一系列行之有效的预防、监测、调查、评估等管理工作,为污染场地的识别和筛选奠定了坚实的基础。对于污染场地的整治工作,采用标准和风险评估相结合的验收方式,推行场地可持续利用的绿色修复技术。重点研究台湾地区土壤及地下水污染整治工作的管理政策、模式和措施,总结相关经验,为中国土壤及地下水污染防治工作提供借鉴和参考。  相似文献   
584.
Data on the mass density and carbon content of tree organs, and in particular stem wood, are essential for accurate assessments of forest carbon sequestration. However most available data, including that for East Asia, has neglected the volatile C fraction. Wood samples were collected and assayed for C content from 14 native tree species in Jilin Province, NE China. C content showed statistically significant variation among species, ranging from 48.4% to 51.0%. The volatile C fraction was non-negligible, averaging 2.2%, and showed high variation among species. As found in prior studies, wood C content was appreciably higher in conifer than hardwood (angiosperm) species (50.8+/-0.1% vs. 49.5+/-0.2%, respectively). Wood carbon density (gC/cm(3)) showed very high inter-specific variation, due mainly to differences in wood specific gravity. Our analyses, in conjunction with recently published data from North America, indicate a global mean value of 47.5+/-0.5% wood C content exclusive of volatile C; the widely used 50% figure corresponds more closely to total wood C inclusive of the volatile fraction. Failure to include volatile C or to use species- or higher-taxon-specific C content values in forest C assessments is likely to introduce biases on the order approximately 4-6%. In addition, the stocks and flows of the volatile C fraction in wood are in themselves an important and sorely neglected aspect of forest C processes likely to be strongly impacted by harvests and other management practices.  相似文献   
585.
针对目前我国农业生产中的资源环境问题,指出粮食生产成本核算的不完整性,粮食生产造成的资源耗减和环境降级得不到补偿。运用环境经济学原理和可持续发展理论对粮食生产的完全成本进行分析,提出粮食生产的完全成本除包括直接生产成本外,还应包括粮食生产的资源环境成本。论文以南方红壤丘陵区的湖南省祁阳县为研究对象进行案例分析,研究表明,2008年该区域粮食生产的资源环境成本相当于当年农业总产值的36.55%;早、中、晚稻的完全成本分别达到4.27、3.84和4.40元·kg-1,其中资源环境成本分别为1.38、 1.65和1.64元·kg-1,直接生产成本分别为2.89、 2.19和2.76元·kg-1,而实际市场价格分别仅有1.76、 1.90和1.84元·kg-1。研究结果对有关部门制定相关农业政策、调整粮食生产布局、促进区域粮食生产和可持续发展具有一定的参考价值。  相似文献   
586.
China's circular economy is still at the initial stage, whose development has many difficulties and problems requir- ing immediate resolution theoretically and practically. Due to the differences of re...  相似文献   
587.
The current status of ecotourism in rural China was analyzed in this paper.Empirical surveys covering the whole country indicate that ecotourism in rural China has attracted a large number of tourists who,however,didn’t generate revenues that can match the number.Although the environmental quality of those rural ecotourism destinations is high with little negative impacts,several problems have already appeared,suggesting a need to monitor those areas.The current practice of interpretation in most rural ecotourism destinations did not provide environmental education opportunities to the tourists.And local communities need more effective ways to decide on the prospects of local ecotourism development by themselves.Finally,a few recommendations for improving the sustainability of ecotourism destinations were provided.  相似文献   
588.
Environmental planning at different levels has been called for by environmental departments in China during last years to integrate environment consideration to economic development. Based on the accomplished environmental planning practice in Xiamen China, the paper suggests a general environmental planning process with ecological function zoning as its key steps, at the same time an effective method for ecological function zoning was formulated. The case studies of Dongfu suburban town environmental planning and Xiamen eco-city conceptual planning indicate that scientifically sound results of ecological function zoning can contribute to improving not only the adaptability and acceptability of environmental planning, also the environmental management and the decision-making. The experience shows that the ecological function zoning methods should be applied according to the principles of adaptive management, resource-based and community-based, so that it can integrate science into decision-making process, avoiding both narrow-minded viewpoints of planners and natural resource use conflicts among variety of stakeholders. Problems to be resolved in the future are also pointed out in the ending part.  相似文献   
589.
我国环境中有机污染物分析方法及痕量富集技术的进展   总被引:10,自引:8,他引:10  
综述了我国环境中有机污染物的分析方法和痕量富集技术,介绍了吹扫-捕集法、固相微萃取技术、固相萃取技术、半渗透膜采样技术与分析仪器联用在有机污染物测定中的应用情况。  相似文献   
590.
The lack of high-resolution distribution maps for freshwater species across large extents fundamentally challenges biodiversity conservation worldwide. We devised a simple framework to delineate the distributions of freshwater fishes in a high-resolution drainage map based on stacked species distribution models and expert information. We applied this framework to the entire Chinese freshwater fish fauna (>1600 species) to examine high-resolution biodiversity patterns and reveal potential conflicts between freshwater biodiversity and anthropogenic disturbances. The correlations between spatial patterns of biodiversity facets (species richness, endemicity, and phylogenetic diversity) were all significant (r = 0.43–0.98, p < 0.001). Areas with high values of different biodiversity facets overlapped with anthropogenic disturbances. Existing protected areas (PAs), covering 22% of China's territory, protected 25–29% of fish habitats, 16–23% of species, and 30–31% of priority conservation areas. Moreover, 6–21% of the species were completely unprotected. These results suggest the need for extending the network of PAs to ensure the conservation of China's freshwater fishes and the goods and services they provide. Specifically, middle to low reaches of large rivers and their associated lakes from northeast to southwest China hosted the most diverse species assemblages and thus should be the target of future expansions of the network of PAs. More generally, our framework, which can be used to draw high-resolution freshwater biodiversity maps combining species occurrence data and expert knowledge on species distribution, provides an efficient way to design PAs regardless of the ecosystem, taxonomic group, or region considered.  相似文献   
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