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421.
Octanol‐water partition coefficients (Kow) and soil organic carbon sorption coefficients (Koc) were determined for 14 fluorinated benzene derivatives. Quantitative structure‐property relationships were developed using molecular connectivity indices and quantum chemical parameters to analyze the most significant factors influencing these physico‐chemical properties of the compounds. The substitution by F in benzene derivatives has greater influence on Koc than on Kow. 相似文献
422.
The ecological footprint (EF) is a method for measuring sustainable development through ecological impact. A methodology is presented for predicting urban ecological footprints. Urban energy use and natural resource consumption were analyzed to calculate an EF based on land type (arable, pasture, forest, fossil energy land, built-up area and water area) and consumption (food, housing, transportation, goods, services and waste). The result was then compared with the local ecological carrying capacity to develop criteria for sustainable ecological footprints. Case studies of four cities in China (Guangzhou, Ningbo, Suzhou and Yangzhou) illustrate the urban EF approach. The time series of EF in a case study of Guangzhou for 1991–2001 was analyzed and the consumption–land-use matrix of urban EF was established. The results show that the cities are ecologically unsustainable, with average ecological conflicts per capita of more than 2 ha. The urban EF method is useful to measure urban sustainable development and provides policy proposals for decision-making. However, the EF method still has limitations and weaknesses. 相似文献
423.
China has about 20% of the world's population. With rapid economic development and substantial population increase, China is now faced with severe conflicts between limited natural resources and increasing resource requirements. In this study, we used the ecological footprint method to assess the resource demand and supply conditions of each land use in China between 1978 and 2003. In order to provide insight into the spatial heterogeneity of resource demand and supply conditions, we also assessed the ecological footprint at provincial level in 2002. An ecological footprint curve method was introduced to compare differences in natural resource use, economic development and technological progress among different countries and provinces. The results showed that the ecological footprint, biocapacity and ecological deficit per capita for China have all been increasing during 1978–2003. The ecological footprints per person in northern and eastern China were larger than those in southern and western China. The ecological deficits per person in southern and eastern China were more severe than those in northern and western China. Though the resource use efficiency has increased considerably during 1978–2003, it was still much lower than those of the Netherlands, France, South Korea, Mexico, the Philippines and India. 相似文献
424.
Zhaoyu Zhu Jiubing Xie Jianguo Zhang Huaxian Liang Yan Qiu Zhen Xia 《国际发展与全球生态学杂志》2013,20(4):421-427
Prevention and treatment of geological hazards is important for the sustainable development of human society. Surface geological hazards alone caused direct economic losses of ¥3.47 billion, with 768 deaths and 785 injuries in Guangdong Province, South China, from 1994 to 2005. The major factors causing geological hazards can be categorised into three types: geo-environmental, climatic-meteorological and human activity. Accompanied by rapid economic development and population growth, human activities can cause geological hazards that are as serious as those caused by natural factors. The authors propose some suggestions for prevention and treatment of geological hazards to achieve sustainable development on the Chinese coast. 相似文献
425.
Lugu lake is an alpine lake in Yunnan Province in western China. It is famous for its beautiful scenery and the special culture of Mosuo people in this area. The lake is becoming contaminated and eutrophicated because of the huge number of visitors and improvements in agriculture during the last decade. This paper uses the water quality index (WQI) as an indicator to describe trends in contamination of Lugu Lake from 1995 to 2004 and analyses several parameters to determine the causes and consequences of contamination. We found that the dominant cause was pollution from tourism and suggest some feasible measures to prevent further deterioration of the lake water quality. 相似文献
426.
Jianfeng Zhang Guang-Cai Chen Shangjun Xing Qixiang Sun Qihua Shan Jinxing Zhou 《国际发展与全球生态学杂志》2013,20(6):475-480
The Yellow River Delta region in China is a land area of 1,200,000 ha with rich natural resources. Adverse environmental conditions, such as low rainfall and high salinity, promote the dominance of black locust trees for afforestation. With the increase of CO2 in the atmosphere, this forest and others throughout the world have become valued for their ability to sequester and store carbon. Forests store carbon in aboveground biomass (i.e. trees), belowground biomass (i.e. roots), soils and standing litter crop (i.e. forest floor and coarse woody debris). There are well-developed methods to sample forest ecosystems, including tree inventories that are used to quantify carbon in aboveground tree biomass. Such inventories are used to estimate the types of roundwood products removed from the forest during harvesting. Based on standard plot inventories and stem analyses, carbon sequestration estimates of trees were 222.41 t ha?1 for the Yellow River Delta region accounted for 67.12% of the whole forest. Similarly, carbon storage by herbaceous matter and soil was 0.50 and 50.34 t ha?1, respectively. The results suggest that carbon sequestration in the forest ecosystem was performed by most of the forest, which plays an increasingly important role in sequestering carbon as the stand grows. 相似文献
427.
Water quality is one of the most serious problems of environment and national sustainable development strategy now facing China. After hard work over the last several decades, urban-sewage treatment in China is now relatively well developed. It now affords mainly higher levels of sewage collection and treatment, as well as pollution-load control. The characteristic rapid urbanization now occurring in China is still increasing and developing dramatically, and involves large numbers of people. However, in towns, sewage treatment infrastructure is inadequate, and a high percentage of the sewage generated there is not effectively collected and treated. The sewage and pollution load of such towns have become the most important reason for environmental water problems in China. To understand the priorities of sewage treatment in such towns, and their spatial distribution in China, we conducted two nationwide investigations of water use and sewage discharge in towns. Based on the integrated analytic hierarchy process (AHP), assessment indices and a framework of town-sewage treatment priorities in China were constructed. Then, we assessed and analyzed the priorities of towns regarding three aspects of sewage treatment: environmental stress, economic capability, and infrastructure. The results showed that the southeast coastal areas and north China had higher demand for sewage treatment than other areas. The demand in eastern and western areas had obvious differences in spatial distribution, but had nearly no differences within those areas. The towns having the greatest demand for high-priority sewage treatment were concentrated in regions with high economic capability and intense water resource utilization. 相似文献
428.
Study of the ecology of mesopelagic fishes is central for assessing the active biological pump in the ocean, especially in the mesopelagic layers. The use of δ13C and fatty acid analysis can help to analysis the ecology of mesopelagic fishes. Here, we analysed the fatty acid composition of mesopelagic fishes from the continental northern slope of the South China Sea (NSSCS) and compared with nearshore SCS fishes and mesopelagic fishes collected from the Southern Ocean. The mesopelagic fishes had unusually high lipids, which resulted in Δδ13C values exceeding 1‰, more than the enrichment factor in the food web. The mesopelagic fishes had higher C18:1n-9/C18:1n-7 and C20:1n-9/ C18:1n-7 ratios compared with other fishes in the SCS, which confirmed that plankton were their main dietary source. The mesopelagic fishes from SCS and Southern Ocean had different ratios of C20:5n-3/C22:6n-3 (EPA/DHA), suggesting geographical locations and diet sources had obvious influence on their fatty acid composition. The SCS mesopelagic fishes had higher C20:4n-6/C22:6n-3 (ARA/DHA) and C20:4n-6/C20:5n-3 (ARA/EPA) ratios than mesopelagic fishes in the Southern Ocean, indicating the influence of physical factors on fatty acid composition. Thus, future studies of the fatty acids in mesopelagic fishes should consider both dietary sources and physical environments. 相似文献
429.
Large quantities of herbicides are used on agricultural soils, but the effects of herbicides on the structure of the soil microbial community have not been well investigated. In this study, soil from three soybean fields was investigated. The herbicide imazethapyr was applied in one year to soil 1 and in two sequential years to soil 2. Control soil received no imazethapyr. Microbial biomass and community structure were characterised using chloroform fumigation–extraction and phospholipid fatty acid (PLFA) determination. The imazethapyr residue was 1.62 μ g·kg?1 in soil 1 and 1.79 μ g·kg?1 in soil 2. The microbial biomass carbon and total PLFAs for soil 2 were much higher than for the other soils. PLFA profiles showed that fatty acids for Gram-negative and Gram-positive bacteria, as well as total bacteria and total fungi in soil 2 were higher than in other samples. Principal component analysis of the PLFAs showed that the structure of the microbial community differed substantially among the three different soybean field soils. Application of the herbicide imazethapyr to soybean fields clearly changed the soil microbial biomass and shifted the structure of the microbial community. 相似文献
430.
太湖水体中5种有机磷农药混合物生态风险评价 总被引:2,自引:0,他引:2
有机磷农药是一类广泛分布于我国水环境中的污染物,即使在水体中的污染水平处于规定“安全标准”之下,其联合暴露产生的风险仍有可能威胁水生生态安全。采用基于浓度加和模型与生物敏感度分布曲线的混合物风险商法,评价了太湖水体中敌敌畏、对硫磷、甲基对硫磷、马拉硫磷和乐果5种有机磷农药混合物产生的生态风险。结果表明:2003~2004年期间3个不同时期太湖水体中5种有机磷农药的混合物生态风险商(RQm )均大于1,有机磷农药混合物在2003~2004年期间对太湖水生生物构成了一定威胁。 相似文献