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1.
辽宁省及其沿海区域生态足迹的动态变化   总被引:3,自引:0,他引:3  
利用生态足迹分析法方法计算了辽宁省及其沿海6市(葫芦岛、锦州、盘锦、营口、大连和丹东)2003-2005年的生态足迹,分析了生态足迹的变化规律及变化原因,并评价了该区域可持续发展状况.结果表明:2003-2005年辽宁省及其沿海6市的生态足迹均超过了其生态承载力,全省人均生态赤字有逐年增加的趋势;沿海6市中人均生态赤字最高的城市为盘锦市,然后依次为锦州市、葫芦岛市、营口市、丹东市和大连市.生态足迹供需结构表明,辽宁省及沿海生6市生态足迹需求主要以化石能源地为主,但均有较高的水域类生态盈余.3年间万元GDP生态足迹总体呈下降趋势,表明辽宁省及其沿海6市的资源利用率不断提高.最后提出了减少区域生态赤字的对策.  相似文献   

2.
Ecological restoration studies have been widely conducted for many years to solve eco‐environmental problems. However, no publications offer a systematic and quantitative analysis of the evolution of the field of ecological restoration. To address this knowledge gap, for the first time, we applied a bibliometric analysis approach to analyze ecological restoration studies. We analyzed 3,929 articles published between 1988 and 2017 catalogued in the Science Citation Index Expanded database and the Social Sciences Citation Index database. The results show that annual article output stably increased after 2004, and the number of annual articles of each country has also increased notably since then. The United States occupies the leading position in ecological restoration studies, with China attaining a close second position in recent years. Four institutions and seven journals are outstanding in the field of ecological restoration. Academic collaborations of authors or institutions exhibit an increasing trend, but international collaboration needs to be strengthened because eco‐environmental problems are a global challenge. Forest, grassland, and wetland ecosystems have received the most attention. Biodiversity, ecosystem services, and climate change are core issues of ecological restoration studies and are predicted to remain the research hotspots in the future. Novel ecosystems are likely to become one of the most important research areas in the near future. More importantly, it is crucial for researchers to places more emphasis on social issues of ecological restoration in the future.  相似文献   

3.
Bacterial resistance to antibiotics is often plasmid-mediated and the associated genes encoded by transposable elements. These elements play a central role in evolution by providing mechanisms for the generation of diversity and, in conjunction with DNA transfer systems, for the dissemination of resistances to other bacteria. At the University Hospital of Zaragoza, extensive efforts have been made to define both the dissemination and evolution of antibiotic resistance by studying the transferable R plasmids and transposable elements. Here we describe the research on bacterial resistance to antibiotics in which many authors listed in the references have participated. The aspects of bacterial resistance dealt with are: (i) transferable resistance mediated by R plasmids in Gram-negative bacteria, (ii) R plasmid-mediated resistance to apramycin and hygromycin in clinical strains, (iii) the transposon Tn1696 and the integron In4, (iv) expression of Escherichia coli resistance genes in Haemophilus influenzae, (v) aminoglycoside-modifying-enzymes in the genus Mycobacterium with no relation to resistance, and (vi) macrolide-resistance and new mechanisms developed by Gram-positive bacteria.  相似文献   

4.
Estimates of regional and national topsoil soil organic carbon (SOC) stock change may help evaluating the soil role in mitigation of greenhouse gas (GHG) emissions through carbon (C) sequestration in soils. However, understanding of the exact mitigation role is often constrained by the uncertainty of the stock estimation associated with different methodologies. In this paper, a soil database of topsoil (0–20 cm) SOC measurements of Jiangsu Province, China, obtained from a soil survey in 1982, and from a geological survey in 2004, was used to analyze the variability of topsoil SOC among soil groups and among soil regions, and to estimate the change in SOC stocks that have occurred in the province over the last two decades. The soil survey data was obtained from measurements of 662 690 randomly collected samples, while the geological survey data was from 24 167 samples taken using a 2 km × 2 km grid. Statistical analysis was conducted on SOC values for 1982 and 2004 for different categories of soil groups, soil regions, and administrative municipalities, respectively. Topsoil SOC storage was then calculated and the provincial topsoil SOC stock was estimated for each sampling time. There were remarkable differences in SOC levels between soil groups and soil regions and different municipalities. The grid sampling with the geological survey in 2004 yielded smaller variability of topsoil SOC averages, both with soil groups and with soil spatial distribution than the random sampling method used in 1982. Variation of SOC was greater with soil groups than with soil regions in both sampling times, although it was less variable across soil taxonomic categories than within a spatial category. Little variance of the SOC level with soil groups could be explained by clay content. However, the prevalence of paddy fields in the total cropland area governed the regional and municipal average SOC levels. The average provincial topsoil SOC content increased from 9.45 g kg−1 in 1982 to 10.9 g kg−1 in 2004, and the total provincial topsoil SOC stock was enhanced from 149.0±58.1 Tg C in 1982 to 173.2±51.4 Tg C in 2004, corresponding to a provincial average SOC sequestration rate of 0.16±0.09 t C ha−1 yr−1. The SOC sequestration trend for the last two decades could be, in part, attributed to the enhanced agricultural production, symbolized by the grain yield per hectare. The results of SOC stock changes suggest a significant C sequestration in soils of Jiangsu, China, during 1980–2000, with paddy management playing an important role in regional SOC storage and sequestration capacity.  相似文献   

5.
Leptospirosis is a common zoonotic disease in China. From 1991 to 2010, its average annual incidence was 0.70 cases per 100,000 population. During these two decades, three major outbreaks of leptospirosis occurred due to flooding and heavy rainfall. Leptospira interrogans serogroup Icterohaemorrhagiae serovar Lai is the predominant leptospire responsible for at least 60% of Chinese cases, and Apodemus agrarius serves as the major animal host. Based on the differences in predominant leptospiral serovars, epidemic features and incidence, there are three leptospirosis-prevalent regions in China. However, the incidence has significantly decreased in the last ten years.  相似文献   

6.
生态足迹研究——辽宁省生态足迹计算与分析   总被引:38,自引:5,他引:38  
董泽琴  孙铁珩 《生态学报》2004,24(12):2735-2739
可持续发展的定量测度研究是当前国际上关于生态经济研究的前沿问题之一。生态足迹分析法是近年来发展的用于定量研究和判断一个国家或地区的可持续发展状况的新方法。应用生态足迹的方法 ,以辽宁省 2 0 0 0年 ,2 0 0 1年 ,2 0 0 2年统计资料为依据 ,对其 1999~ 2 0 0 1年 3a的生态足迹进行了实证计算和研究 ,从纵向比较并分析了辽宁省生态足迹的变化规律及其原因。研究结果表明 :辽宁省生态赤字呈逐年增加的趋势 ,1999年人均生态赤字为 2 .2 90 hm2 ,2 0 0 0年为 2 .36 8hm2 ,2 0 0 1年为 2 .4 74hm2 ,其主要影响因素是由于资源过度消耗 ,人口增长以及耕地减少等。通过生态足迹的研究 ,提出了辽宁省在振兴东北老工业基地 ,进行可持续发展过程中应采取的对策措施  相似文献   

7.
随着城市化进程的不断加速,城市遥感研究已成为地理学、生态学、城市规划学等学科领域主要发展方向之一。城市化使人口与经济增长的同时,也使得城市原有的生态环境状况发生改变,从而引起了一系列城市生态环境问题。城市遥感是一门多学科交叉研究领域,近年来已经取得了一系列显著的研究成果。对近年来城市遥感研究涉及的城市地表温度、边界扩张、不透水表面、景观格局以及生态安全5个方面的理论、研究方法、应用动态以及发展方向进行了较为详细的总结与探讨。主要得出如下结论:(1)数据源从单个遥感数据研究走向多源遥感数据融合发展,多源遥感数据尤其是结合高分辨率数据越来越多的被应用到城市研究的各个领域中;(2)城市遥感的研究目标不断扩展、深化和聚焦;(3)城市遥感研究已开始从二维空间向三维空间拓展;(4)城市遥感涉及的研究对象之间相互作用,相互影响在深入解读城市遥感研究理论意义和潜在挑战的基础上,结合最新研究对本文所涉及的主题进行了补充和完善,为城市典型生态环境问题的解决提供新的思路;今后应按照城市形态与构成、城市关键要素、生态环境响应、生态环境评价以及城市扩展与环境预测的体系结构进行综合分析。  相似文献   

8.
Africa’s rate of urbanization is the highest in the world. This is relevant to ecologists working in Africa because urban growth is strongly associated with habitat destruction, and also creates new fields of study. The ecological footprint concept is used to illustrate how urban settlements in Africa impact on rural ecosystems. At an aggregate level, African countries have the lowest ecological footprints in the world. However, there is little available data for individual cities, so evidence is fragmented making concerted policy initiatives difficult. Wood fuel continues to be a major source of energy for urban households and there is a long running debate as to what extent providing wood fuel for urban use damages forest ecosystems. Growing evidence contests the assertion that urban wood fuel markets are responsible for forest degradation. Although there are other options available, the social consequences of switching energy sources need to be taken into account. Outright bans, for example on charcoal, would lead to a loss of livelihoods in rural and urban households, and may not solve deforestation as well as increasing fossil fuel use would increase the ecological footprint.  相似文献   

9.
This article, written by two entrepreneurs in luminescence, traces their involvement in the major part of the interconnected innovation and development of luminometers, adenosine triphosphate (ATP) bioluminescence and other technologies from the mid‐1970s to 2011 that ushered in much of the field of luminometry as we know it today. Key developments leading to current commercial applications of ATP bioluminescence, luminescence immunoassay, cellular luminescence, reporter gene and other applications are described from the first tube luminometers derived from early luminescence studies using liquid scintillation counting technology to measuring bioluminescence from crude ATP and firefly tail extracts. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

10.
甘肃省河西绿洲农业区生态足迹动态研究   总被引:22,自引:3,他引:22  
研究了甘肃省河西绿洲农业区1949~2000年生态足迹的动态变化、区域可持续发展程度及未来可持续发展的趋势.结果表明,河西全区的人均生态足迹在1949~2000年呈递增趋势,从0.426hm^2增加到2.158hm^2。1949~1970年平均为0.693hm^2,1975~1980年平均为1.029hm^2,1985~2000年平均为2.288hm^2:人均生态承载力由1949年的0.550hm^2增加到2000年的1.762hm^2,与人均生态足迹相比,增幅较小,增速亦慢.1949~1970年平均为0.782hm^2,1975~2000年平均为1.715hm^2;1949—1975年为生态盈余阶段,平均盈余为0.088hm^2,1980年首次出现赤字,1985年又恢复为盈余,到1991年后持续出现生态赤字。且赤字程度为加速度负增长,1991~2000年平均赤字为0.258hm^2.河西全区的区域经济正朝远离可持续的方向发展,且已处于不可持续状态.  相似文献   

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