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911.
This article argues that climate change, seen as a socially constructed anticipation of natural disasters and a future-risk that plays out in present politics, is enabling the emergence of new modes of governance in cities of the global south. The article focuses on the process by which the city of Esmeraldas, Ecuador, developed a Climate Change Adaptation and Mitigation Strategy. Within the context of climate change adaptation, Esmeraldas mobilised new discourses, stakeholders, and planning mechanisms to address pre-existing urban planning and development limitations. This discursively enabled the municipality's ongoing governance project by leveraging resources, creating consensus, and informing practice. Climate change adaptation thus became an important mechanism for engaging with local priorities, particularly those of the most vulnerable populations, and for bridging the gap between the formal world of policymaking and the reality of life in the city, which is more often structured by informality.  相似文献   
912.
This paper makes a proposition that Epworth's current housing management policies, regulations and practices do not promote easy access to formal standard housing and secure tenure in peri-urban and urban areas for low-income groups. In constructing this paper, both qualitative and quantitative methodologies were used. The qualitative methods adopted include key informant interviews, observations of the environmental aspects of the study area and documentary analysis of secondary data housed in the local board (Epworth Local Board) offices. The major findings demonstrate the reasons for high levels of squatting in Epworth, the local board's housing and development control policy, the relationship between poverty and informal settlements, the informal settlers' capacity to meet the costs of planned and serviced stands and policy options for both the central government and the local board which can be adopted to alleviate poverty in informal settlements. Evidence on the ground points to the fact that perpetuated animosity among groups in a settlement hinders the growth and development of that place. Epworth is a victim of disharmony of the groups residing there. It is the group dynamics that are very influential in making or breaking development in a place. The government official position on Epworth in this study stands unconvincing regarding the jeopardy of bad stewardship by the so-called responsible authority.  相似文献   
913.
烟台门楼水库水环境容量研究   总被引:3,自引:1,他引:3  
根据烟台市1998年~2003年地表水环境质量监测数据,评价了门楼水库的水环境质量现状,从其水质变化趋势可知,近年来,门楼水库水质趋于好转。根据烟台市确定的水质保护目标,选用适合于门楼水库水环境特征的水质模型,分别计算COD、BOD、TN、TP的水环境容量。根据2003年门楼水库的水质监测数据,又分别计算了这四个指标的已利用环境容量和剩余环境容量。结合作者对门楼水库的相关研究,提出加强面源污染控制的建议。  相似文献   
914.
Abstract:  The consequences of climate change will affect aquatic ecosystems, including aquatic invasive species (AIS) that are already affecting these ecosystems. Effects on AIS include range shifts and more frequent overwintering of species. These effects may create new challenges for AIS management. We examined available U.S. state AIS management plans to assess each program's capacity to adapt to climate-change effects. We scored the adaptive capacity of AIS management plans on the basis of whether they addressed potential impacts resulting from climate change; demonstrated a capacity to adapt to changing conditions; provided for monitoring strategies; provided for plan revisions; and described funding for implementation. Most plans did not mention climate change specifically, but some did acknowledge climatic boundaries of species and ecosystem sensitivities to changing conditions. Just under half the plans mentioned changing environmental conditions as a factor, most frequently as part of research activities. Activities associated with monitoring showed the highest capacity to include information on changing conditions, and future revisions to management plans are likely to be the easiest avenue through which to address climate-change effects on AIS management activities. Our results show that programs have the capacity to incorporate information about climate-change effects and that the adaptive-management framework may be an appropriate approach.  相似文献   
915.
我国自然资源的承载力分析   总被引:21,自引:1,他引:20  
发展与资源环境有着非常密切的依赖关系,这种实际存在的关系并不像目前流行的知识经济所设想的那样,可以通过开发技术从根本上加以改变。可持续发展不是不消耗资源。不是使发展完全摆脱对资源环境的影响和依赖,而是要将发展保持在资源环境可承载能力的限度以内。又不能使发展处于停滞状态。总体分析我国资源环境的承载力。表明:①生态空间严重不足,全国大范围出现生态赤字,但把不可再生资源计算在内的生态承载力还有巨大空间;②从全国范围来看,目前人口数量规模在水资源人口承载能力范围之内。但一些地区表现出水资源人口严重超载:③我国土地的人口承载力略有剩余,保持长期稳定的温饱具有自然资源保障基础:④我国能源矿产结构性矛盾十分突出,石油矿产长期短缺已成定局。石油能源承载能力明显不足;⑤总体上我国人口和经济发展还没有超出自然资源的承载力限度,但部分地区和部分自然资源严重超载。因此。对于目前我国资源环境的总体状况,我们既不能过分乐观也不能过分悲观的估计。总体上我国人口和经济规模还没有超越自然资源所能承载的限度。  相似文献   
916.
Abstract:  Funding of ecological research and monitoring of Neotropical migratory birds on their overwintering grounds has benefited both migratory and permanent-resident species. Using examples from our work in Puerto Rico and the Dominican Republic, we demonstrate that ecological research of overwintering migrants often provides information about the ecology and demography of little-known tropical resident birds. Critically important long-term monitoring in Puerto Rico with a focus on winter residents has provided information on the relationships between annual rainfall and fluctuations in resident bird populations and survival rates. It also has alerted local biologists to declines in resident bird populations, including a decline apparently driven by the entry of a brood parasite. But migrant-focused research may also have had an underappreciated effect on the development of conservation capacity and conservation efforts in host countries. Investments in research on Neotropical migrants overwintering on Hispaniola have resulted in a huge increase in field training of students and wildlife professionals, promoted conservation awareness at local and national levels, played an important role in the growth and professionalization of key environmental organizations, spawned a growing ecotourism industry for bird-watching, and driven national park management planning and conservation efforts for all bird species. We encourage funding organizations and agencies to consider the broader impacts of funding migratory-bird research and monitoring efforts, and we encourage researchers in the tropics to use protocols that provide the most information about all the birds that use the study areas involved and to be aware of important opportunities that they may have to build capacity in host countries.  相似文献   
917.
In this paper we develop a novel, comprehensive method for estimating the global human carrying capacity in reference to food production factors and levels of food consumption. Other important interrelated dimensions of carrying capacity such as energy, non-renewable resources, and ecology are not considered here and offer opportunities for future work. Use of grain production (rain-fed/irrigated), animal product production (grazing/factory farm), diet pattern (grain/animal products), and a novel water accounting method (demand/supply) based on actual water consumption and not on withdrawal, help resolve uncertainties to find better estimates. Current Western European food consumption is used as a goal for the entire world. Then the carrying capacity lies in the range of 4.5–4.7 billion but requiring agricultural water use increase by 450–530% to 4725–5480 km3, the range based on different estimates of available water. The cost of trapping and conveying such water, will run 4.5–13.5 trillion over 50 years requiring an annual spending increase of 150–400%, straining the developing world where most of the population increase is expected. We reconfirm estimates in the literature using a dynamic model. ‘Corner scenarios’ with extreme optimistic assumptions were analyzed using the reasoning support software system GLOBESIGHT. With a hypothetical scenario with a mainly vegetarian diet (grazing only with 5% animal product), the carrying capacity can be as high as 14 billion. Ecological deterioration that surely accompanies such a population increase would negatively impact sustainable population. Using our approach the impact of ecological damage could be studied. Inter- and intra-regional inequities are other considerations that need to be studied.  相似文献   
918.
刘晓烨  张洪  李永峰 《环境科学》2014,35(6):2433-2438
水力停留时间(HRT)是厌氧生物制氢工艺的重要工程参数.以红糖废水为底物,研究了HRT对复合式厌氧折流板反应器(HABR)作为乙醇型发酵制氢系统产氢效能的影响.结果表明,在设定的8~36 h范围内的5个HRT中,当HRT为12 h时,HABR制氢系统的效果最佳,产氢速率为13.86 mmol·(h·L)-1,COD去除率为51.51%,五格室的pH值在4.22~4.47之间,液相主要产物为乙醇和乙酸,第1~5格室乙醇和乙酸的比值分别为1.90、1.94、1.80、1.77、1.91,最佳能量生产为11.11 kJ·(h·L)-1.  相似文献   
919.
北京常见绿化树种叶片富集重金属能力研究   总被引:3,自引:0,他引:3  
李少宁  孔令伟  鲁绍伟  陈波  高琛  石媛 《环境科学》2014,35(5):1891-1900
以北京地区常见绿化树种为研究对象,测定叶片和土壤重金属含量,对其季节变化规律和污染程度的相关性进行分析,探究植物叶片对土壤中重金属的富集能力.结果表明:①植物叶片中重金属Cu、Pb、Zn含量随季节变化(由春到冬)呈先下降后升高再下降的变化趋势;Cr含量变化呈先升高后下降的趋势,秋季达最高值;春、夏、秋这3季对Cu富集能力较强的为柳树和国槐,冬季为油松;对Cr、Pb富集能力较强的是国槐和侧柏,冬季为侧柏和白皮松;对Zn富集能力较强的为柳树和白皮松,冬季为侧柏;②由市中心至远郊,4种重金属(Cu、Cr、Pb、Zn)污染程度为:景山(C=2.48,C为污染系数)>奥林(C=1.27)>松山(C=1.20)>水关(C=1.18);③水关长城景区植物叶片中重金属含量变化较大,其它3个研究区域重金属含量排序为:景山>奥林>松山;同一树种叶片对不同重金属富集能力排序均为:Zn>Cu>Pb>Cr,且Zn含量与Cr含量差异极显著(P<0.01);④植物叶片中重金属含量与土壤中相应重金属元素污染程度呈二次多项式关系,除Cu元素外,其余3种重金属元素含量与土壤中重金属污染程度相关性较强,且相关系数均达0.9以上.  相似文献   
920.
The strategy of choosing suitable plants should receive great performance in phytoremediation of surface water polluted by triazophos(O,O-diethyl-O-(1-phenyl-1,2,4-triazol-3-base) sulfur phosphate, TAP), which is an organophosphorus pesticide widespread applied for agriculture in China and moderately toxic to higher animal and fish. The tolerance, uptake, transformation and removal of TAP by twelve species of macrophytes were examined in a hydroponic system and a comprehensive score(CS) of five parameters(relative growth rate(RGR), biomass, root/shoot ratio, removal capacity(RC), and bio-concentration factor(BCF)) by factor analysis was employed to screen the potential macrophyte species for TAP phytoremediation. The results showed that Thalia dealbata, Cyperus alternifolius, Canna indica and Acorus calamus had higher RGR values, indicating these four species having stronger growth capacity under TAP stress. The higher RC loading in Iris pseudacorus and Cyperus rotundus were 42.11 and 24.63 μg/(g fw·day), respectively. The highest values of BCF occurred in A. calamus(1.17), and TF occurred in Eichhornia crassipes(2.14). Biomass and root/shoot ratio of plant showed significant positive correlation with first-order kinetic constant of TAP removal in the hydroponic system, indicating that plant biomass and root system play important roles in remediation of TAP. Five plant species including C. alternifolius, A. calamus, T. dealbata, C. indica and Typha orientalis, which owned higher CS, would be potential species for TAP phytoremediation of contaminated water bodies.  相似文献   
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