首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
The aim of this study is to address the problem of balance between water scarcity and sustainability, which are the key components of water security of cities located in arid lands, particularly those under constant expansion and population growth. In this paper, we have highlighted the problem of water security for the sustainability of the La Serena-Coquimbo conurbation (LSCC). The coastal LSCC is located at the outlet of the Elqui River basin, in the southern edge of the Chilean Atacama Desert. We have analyzed the available information including drinking water production and consumption data, groundwater levels, precipitation data and population data. Between the years 2009 and 2013 the total water consumption for the area has significantly increased. On the other hand, there has been a significant decrease trend in the precipitations and the groundwater levels show a decrease of about 30 m between the years 1995 and 2014. In a few years, this urban area could face a general water scarcity problem if the drought conditions remain unchanged and if the water demand trend for the agricultural, mining and drinking water continues its increasing. The cities located in the arid lands are particularly vulnerable to water scarcity because their populations are highly concentrated and requires reliable supplies of water to make possible human and economic activities. We discuss how adaptation of the arid land urban areas to water scarcity requires a range of solutions, including economic incentives, regulatory measures, and technology.  相似文献   

2.
Supplying electricity to remote rural communities in lesser developed countries (LDCs) is key to improving livelihoods and reducing poverty. Decentralised renewable energy systems such as solar photovoltaic (PV) electricity have the potential to provide a viable and sustainable alternative to overcome the physical and economic barriers facing the expansion of low and medium tension grids. This paper critically assesses the impact of small-scale PV systems installed in homes, schools and public buildings over the last six years under the PERMER project—Renewable Energy Project for the Rural Electricity Market—co-funded by a range of public and private sources. The structure of financial subsidies has enabled these remote rural communities to receive an electricity supply that, in many cases, would otherwise not have been possible. Replacing traditional energy sources such as candles and kerosene lamps, the PV electricity systems are providing better quality light, reducing indoor air pollution levels, as well as a means to power communications technologies and extend hours for cultural and productive activities. There are, however, certain technical, organisational and intellectual barriers that remain to be overcome before the project can be considered to be operating optimally.  相似文献   

3.
Field voles (Microtus agrestis) were trapped in 14 field margins and their behavioural and demographic parameters measured. Strong support was found for thresholds in margin width below which vole abundance was extremely low. Narrow margins were male biased with individuals moving greater distances and a large proportion of males behaved as transient individuals. However, no effect was observed on the age structure or survival of the population. Individuals were able to compensate for the lack of habitat through alterations in their behaviour sufficiently to maintain their survival. Within intensive agro-ecosystems, narrow strips between crops are important links for voles between wider margins and, if available, other more suitable habitats. Maintenance of narrow margins, along with larger areas of suitable habitat, is therefore effective in farmed landscapes for sustaining populations of specialist species where they show sufficient flexibility.  相似文献   

4.
广州市花都区2004年生态足迹和生态承载力计算分析   总被引:3,自引:0,他引:3  
以广州市花都区国民统计资料(2004年)和相关统计资料为依据,对花都区生态足迹和生态承载力进行了计算和分析,结果表明广州市花都区人均生态足迹为2.43hm^2/人,人均生态承载力为0.31hm^2/人,人均生态赤字为2.12hm^2/人,属于人均水平亏缺较高的区域。  相似文献   

5.
Food and Environmental Virology - Berries have been implicated as the probable vehicle of infection in multiple outbreaks of norovirus and hepatitis A virus (HAV). These foods often receive minimal...  相似文献   

6.
Bamboo presents physical and mechanical characteristics, which turn it an alternative option for product development, replacing native or reforested wood. The sustainability assessment of a Dendrocalamus Giganteus species plantation in Brazil through the emergy methodology evidences a great weight of renewable (30% sej/sej) and human labour contributions (33% sej/sej). These contributions account for the great interface with environment and to the intensive work, respectively. The transformity value of bamboo production is 2.42E + 04 sej/J. The influence human labour has on the total emergy flow and on indicators is evaluated by taking into account different country locations (Brazil, Australia and China). Thus, a different transformity value for labour is assumed for each country. A ranking based on emergy sustainability index (ESI) values shows that bamboo production in China was the first placed, followed by Brazil and Australia (values of 1.18, 0.50 and 0.09, respectively). The insertion of indirect renewability embedded in labour results in the ranking modification, leading to plantation in Brazil in the first place, followed by the Australian and Chinese ones. The relative position of the bamboo systems is visualized in the ternary diagram expressed in terms of emergy. In an attempt to explore the relationship between sustainability and time, a graphic of ESI vs. global productivity is discussed in terms of a prospective evaluation. Indirect support areas of the bamboo production are calculated as a way to evaluate the sustainability-space relationship.  相似文献   

7.
The aim of the present study was to produce biodiesel from mixtures of cooking oil and provide a possible environmental solution for the region of Campinas (state of São Paulo, Brazil) based on the theory of environmental cost accounting (ECA). Cooking oil collected from homes in Campinas was mixed with ethanol at a ratio of 7:1 and transesterified at 60 °C for one hour for the obtainment of biodiesel using NaOH as a catalyst. The results of the physicochemical analyses demonstrated that the biodiesel possessed characteristics close to those required by Brazilian standards. A recent survey carried out in the city of Campinas revealed that residents are not concerned with the increased of environmental impact and ecological costs in the region caused by the disposal of used cooking oil, which is discarded in sewers and soil. Urgent action is recommended, beginning with raising awareness among the population and the implementation of a policy to determine the storage, periodic collection and use of cooking oil for the production of biodiesel. This fuel could be used for buses, trucks and machines or sold to fuel distributors, offering a savings of US$ 0.8 to 4.5 millions. Campinas could then gain environmental credits and become a sustainable city. Moreover, used cooking oil constitutes low-cost biodiesel with no consumption of raw materials and will reduce worldwide criticism directed at Brazil regarding the use of oleaginous plants for biodiesel production.  相似文献   

8.
Environmental surveillance is an effective approach to investigate the circulation of human enteroviruses in the population. Enteroviruses E14, CVA9, E-6, E16, E20, E25, E13, and CVA24 were detected in sewage and a watercourse in central Argentina. E14 was the most frequent serotype and was found for the first time in environmental samples in our region. Phylogenetic and coalescence analyses showed at least two recent introduction events.  相似文献   

9.
生态足迹方法:辽宁省2005—2007年生态足迹计算与分析   总被引:3,自引:0,他引:3  
张威  张恒庆 《环境科学与管理》2010,35(6):150-153,156
如何定量研究可持续发展是目前国际上研究的热点问题,生态足迹分析法即是一种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。文章应用生态足迹的方法,以辽宁省2006年-2008年统计年鏊资料为依据,对2005年-2007年的生态足迹进行了计算和研究,纵向比较分析了这3年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2005年-2007年3年的人均生态赤字分别为2.718hm^2,2.8942hm^2,3.1348hm^2,呈现逐年上升趋势,生态赤字表明辽宁省的人类负荷超过了其生态承载力,不利于可持续发展。其影响因素为化石能源消耗大、耕地面积减少、建筑用地逐渐增加等。最后提出了减少辽宁省生态赤字的对策。  相似文献   

10.
湖北省土地生态安全预警评价及调控   总被引:4,自引:0,他引:4  
让绿色主导发展方向,有利于湖北省建成生态省。以湖北省为例,运用PSR模型构建指标体系,采用熵权法、灰色预测模型等对2005-2014年湖北省土地生态安全进行了分析,并对2015-2020年湖北省土地生态安全值进行预测,利用障碍度模型识别湖北省土地生态安全主要障碍因子。研究结果表明:(1)从2005年0.459 6(中警)到2014年0.365 5(轻警),湖北省土地生态安全值呈下降趋势,生态环境朝良性方向发展。(2)用GM(1,1)模型预测湖北省2016年生态安全值为0.354 5(轻警)、2020年为0.295 0(轻警),土地生态安全状态良好,朝着"无警"发展。(3)从准则层障碍度来看,压力层从2005年到2014年呈现着快速下降趋势,而状态层和响应层障碍度逐年趋同;制约其向"无警"等级指标有:自然保护区比重、万元GDP能耗、水土流失面积比例、第三产业比重、森林覆盖率、人均耕地面积、粮食单产等,这是今后调控的重点。  相似文献   

11.
循环经济是一种新兴的经济发展模式,发展循环经济是实施可持续发展战略的重要途径和实现方式.本文提出在南充市顺庆区发展循环经济,可以全面提高资源利用效率、增加经济效益、改善环境质量,带动南充经济实现飞速发展.  相似文献   

12.
Recent studies on ecological networks have quantified the contribution of ecological, historical, and evolutionary factors on the structure of local communities of interacting species. However, the influence of species’ biogeographical traits, such as migratory habits or phylogeographical history, on ecological networks is poorly understood. Meta-networks, i.e., networks that cover large spatial extensions and include species not co-occurring locally, enable us to investigate mechanisms that operate at larger spatial scales such as migratory patterns or phylogeographical distributions, as well as indirect relationships among species through shared partners. Using a meta-network of hummingbird-plant interaction across Mexico, we illustrate the usefulness of this approach by investigating (1) how biogeographical and morphological factors associate with observed interactions and (2) how species-specific biogeographical characteristics associate with species’ network roles. Our results show that all studied hummingbird and plant species in the meta-network were interrelated, either directly or through shared partners. The meta-network was structured into modules, resulting from hummingbirds and plants interacting preferentially with subsets of species, which differed in biogeographical, and, to a lesser extent, morphological traits. Furthermore, migrants and hummingbirds from Nearctic, Transition, and widespread regions had a higher topological importance in the meta-network. Our study illustrates how meta-networks may contribute to our current knowledge on species’ biogeographical traits and biotic interactions, providing a perspective complementary to local-scale networks.  相似文献   

13.
Environmental aspects are basic elements in an Environmental Management System (EMS). The identification of environmental aspects is, however, recognized as one of the most complicated parts in establishing an EMS and has been subject to criticism concerning, e.g., lack of transparency and reproducibility. This paper evaluates the Swedish National Rail Administration's (Banverket) current practice for the identification of environmental aspects. A better link between activity, aspect and impact is needed. A more stringent identification procedure would improve Banverket's environmental management. The paper proposes a structured framework for the identification of environmental aspects at Banverket.  相似文献   

14.
15.
采用固相萃取-衍生化-气相色谱质谱方法,研究了江苏省某城市河流中雌激素活性物质的浓度分布特征。研究发现,河水中的雌激素活性物质浓度处于ng/L水平,其中双酚A浓度为100~900 ng/L,雌酮和雌三醇浓度为ND~200 ng/L,辛基酚、17α-雌二醇和17β-雌二醇浓度为ND~20 ng/L。受纳未处理污水的河流中雌激素活性物质浓度高于其他河流的。生态风险评价结果表明,各种雌激素活性物质的生态风险顺序为雌酮>17α-雌二醇≈17β-雌二醇>雌三醇>双酚A、辛基酚和壬基酚。其中,雌酮的风险商约为1~64,约有20%~30%的样品17α-雌二醇和17β-雌二醇的风险商为1~20。因此,该城区河流中应优先控制雌酮、雌二醇等类固醇雌激素。  相似文献   

16.
西南生态脆弱区域农村城镇化水平较低,农村城镇化对区域经济社会发展和生态环境保护具有重要的意义,但农村城镇化也存在对生态环境的影响和破坏。通过分析云南昭通农村城镇化发展的生态增殖效应和胁迫效应,提出相应的生态调控对策,为生态脆弱区城镇的可持续发展探寻更为切实的规划思路。  相似文献   

17.
18.
多元共治视角下湾区城市生态文明建设路径探究   总被引:2,自引:0,他引:2  
我国湾区城市生态文明建设进入了一个新的历史高度,湾区城市建设面临着多种发展机遇,与此同时,生态环境、治理机制、环境利益保障等既有问题也为湾区城市生态文明建设提出了挑战。在此背景下,可以结合《中国国民经济和社会发展第十三个五年规划纲要》提出的"构建政府、企业、公众共治的环境治理体系"要求,从多元共治的角度寻求湾区城市生态文明建设的可行路径。  相似文献   

19.
采用原子吸收光谱法测定了中国南亚热带典型河网湿地(海珠湿地)水域环境表层沉积物中重金属Cu、Zn、Pb、Cd、Ni、Cr、Fe、Mn的含量,通过聚类分析和相关分析方法探讨其重金属的空间分布及来源特征,利用Hakanson生态风险评价法和基于一致性的沉积物质量基准法比较评价该区域重金属污染生态风险。结果显示,海珠湿地水域表层沉积物各重金属含量范围分别为:Cd(0.11~4.37 mg/kg)、Pb(54.9~156.0 mg/kg)、Cr(40.7~225.5 mg/kg)、Cu(34.2~244.9 mg/kg)、Ni(30.9~133.2 mg/kg)、Zn(134.8~669.7 mg/kg)、Fe(2.5%~4.2%)及Mn(0.04%~0.06%),均不同程度地超过区域背景值,且呈狭窄水面向宽阔水面区域递减的空间变化趋势。除Cd在丰水期显著高于枯水期外,其他金属的含量季节差异不显著。各重金属来源及变化趋势表现为两大类群:Cu、Zn、Pb、Cd、Ni和Cr之间具有显著的相关性,可能以人类活动污染为主;而Fe和Mn之间具有显著的相关性,以地壳自然来源为主。海珠湿地总体重金属生态风险较高,应对该区域重金属含量及水生生物状况进行跟踪监测,以维护水域生态系统的健康与平衡。  相似文献   

20.
黄河流域是我国重要的生态功能区,在全国经济社会发展格局中具有重要作用。生态补偿作为保护流域生态环境、促进人与自然和谐的重要手段,在推动黄河流域高质量发展过程中具有重要作用。本文从流域区段、评价方法、影响效应、优化思路、保障机制等方面对黄河流域生态补偿的理论和实践成果进行了综述,同时提出加强多学科协同攻关、构建具有区域特征的生态补偿模式、加快建立以海定陆的生态补偿机制、注重生态损害形成机制和程度评估、加强构建多元化生态补偿保障体系等未来研究中需要深化和完善的几点建议,以期为中国经济高质量发展阶段黄河流域生态补偿的理论与实践研究提供启示和借鉴。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号