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191.
Emily A. Botts Genevieve Pence Stephen Holness Kerry Sink Andrew Skowno Amanda Driver Linda R. Harris Philip Desmet Boyd Escott Mervyn Lötter Jeanne Nel Tammy Smith Fahiema Daniels Samuel Sinclair Warrick Stewart Jeffrey Manuel 《Conservation biology》2019,33(6):1235-1246
Systematic conservation planning is intended to inform spatially explicit decision making. Doing so requires that it be integrated into complex regulatory and governance processes, and there are limited instances where this has been achieved effectively. South Africa is a global leader in the application of conservation plans, the outputs of which are widely used for spatial planning and decision making in many spheres of government. We aimed to determine how conservation planning in the country progressed from theory to implementation, and to identify practical actions that enabled this transition, by assessing temporal trends in the characteristics of conservation plans (1990–2017, n = 94). Since 2010 conservation planning has entered an operational period characterized by government leadership of plans, administrative rather than ecological planning domains, decreasing size of planning units, increasing emphasis on end-user products, and scheduled revision of plans. Key actions that enabled this progression include transitioning leadership of plans from scientists to practitioners, building capacity within implementing agencies, creating opportunities to integrate plans in legislative processes, establishing a strong community of practice, adopting implementation-focused methods, and balancing standardization with innovation. Learning from this model will allow other countries, particularly those with a similar megadiverse, developing context, to operationalize conservation planning into spatial planning and decision making. 相似文献
192.
Academic understandings of environmental discourses are primarily based on global and national accounts, despite widespread acceptance of the local as an essential site of environmental action. Local water issues have been studied in a number of ways, including interviews and ethnographies that show the impacts of water scarcity, examine the role of mediating technologies, and provide diverse perspectives on governance. An overarching impression of key narratives and concerns at local scales, however, is lacking. In this paper, we examine water coverage in The Sowetan, a South African newspaper known for its distinctive voice, as a (albeit imperfect) proxy for local discourse. We identify key themes, location and scale, trigger events, actors, authors, and provide initial insights into the problem frames used in these texts. Our findings show distinct differences from the results of environmental media analyses at other scales, including strong individual citizen voices, emphasis on the politics of water, and rare use of language that accords with global environmental discourses; this also differs from results based on interviews and ethnographies at the local scale. Our findings raise important questions about the resonance of global discourse with local views and practices and how local discourses are produced, and suggest a need to more carefully examine the myriad ways of talking about justice and the environment at different scales and through different methodologies. 相似文献
193.
194.
Technological advances in exploration and production mean that production platforms in Chinese Bohai Bay have many developments that are now operating beyond their original design life. As equipment ages, there are increasing challenges to maintain its integrity. Issues related to LE management of offshore facilities in government regulations, industrial associations and international oil companies were investigated. The results showed that emphasizing the requirements of labor union and industrial associations was a great feature in Norway, which was practical in Chinese Bohai Bay. Therefore, with the combination of the LE management system in Norway with the current situation in Chinese Bohai Bay, LE management model which integrates RBI, RCM, FMECA, and SIL risk assessment methods together was designed in order to improve understanding and ensure that LE issues were addressed across all aspects of asset management during the entire LE period. Finally, an example of three production offshore platforms on a gas field in the Bohai Bay was used to go through the LE management process and address the issues in each phase. The suggestions for improving LE management and technologies were given. 相似文献
195.
Maintaining an adequate air flow with a desired air quality that is free from hazardous gases is among the most important actions taken toward the improvement of safety in any process plant. Due to the increased focus on the consequences of existing hazardous material on safety, health, and the environment, air quality and sufficient ventilation within a plant has been increasingly considered in the design stage. This paper investigates and analyzes methane and hydrogen sulfite dispersion and the effect of air ventilation within a CAD model of an offshore platform using computation fluids dynamics (CFD). In addition, this method and its principals could be utilized in any other hazardous environment. Simulations of possible hazardous events along with solutions for preventing or reducing their probability are presented to better assess the data. These investigations are performed by considering hypothetical hazardous scenarios which consist of gas leakages from pipes and process equipment under different conditions. After drafting a precise and highly detailed CAD model of the plant and performing CFD simulations on this model, the results of gas behaviors, dispersion, distribution, accumulation, and its possible hazards are investigated and analyzed. The larger amount of details of the actual plant model in CFD simulation are obtained by using a combination of different methods and software. These include PDMS for 3-D drawing of the plan, Rinoceros for geometrical integration of the process equipment and facilities, and Sharc Harpoon which meshes the model. Moreover, the probability of inducing ignitable or toxic concentration of gases within the atmosphere and air ventilation of the unit is considered by these investigations. 相似文献
196.
The secondary tropical forests in southern China have suffered from frequent human disturbance and increasing high N deposition. In order to explore the nutrient limitation status in secondary tropical forests of South China, this 3-year field experiment of nitrogen (+N) and phosphorus (+P) addition investigated nitrogen (N) and phosphorus (P) concentrations of the aboveground tissue (leaf and branch) of two widely distributed understory native species Clerodendrum cyrtophyllum and Uvaria microcarpa in a secondary tropical forest of South China. The results showed that: 1) the N and P concentrations of the two species were significantly different (P < 0.001); N and P concentrations of different tissues in the same species were different; N&P addition greatly affected N and P concentrations in branch rather than new leaf and older leaf. 2) +N treatment had no significant effect on N or P concentrations of either species, but significantly decreased N:P ratios (P = 0.001), at the level of 9% for C. cyrtophyllum and 50% for U. microcarpa, respectively. 3) +P treatment had no significant effect on tissue N concentrations, but significantly increased plant P concentrations (P < 0.001), at 54% for C. cyrtophyllum and 88% for U. microcarpa, respectively; +P treatment significantly decreased plant N:P ratios (P < 0.001), at 28% and 60%, respectively. 4) The alterations of P concentrations of two species had significantly negative correlations with N:P alterations under +N/+P treatment (P < 0.001), suggesting that the alteration of P concentrations in plant tissue was the major driver for N:P alteration. Our results show that N and P addition would affect tissue N and P concentrations of the two species, with +P treatment having relatively greater effect on nutrient concentrations than +N treatment; the branch is more sensitive than new or older leaf in response to nutrient addition. Therefore, P availability may be the limiting factor for plant growth in the tropical forests. 相似文献
197.
在分析南湖水质的基础上,对重金属进行Pearson相关性分析,并进行了健康风险评价。结果表明Cr、Cu、Zn未超过生活饮用水卫生标准,Cd 和Pb严重超标。 Cu、Zn、Cd、Cr污染存在一定的同源性,而Mn、Fe、Ni、Pb污染具有多源性。污染物通过皮肤接触途径造成的危害要远小于饮水途径,致癌物风险比非致癌物高1~8个数量级,其中Cd对总风险贡献率为62.16%,成为主要的风险污染物。8个监测点都检测到致癌物,且风险度高于可接受水平,应引起环境治理部门的关注。 相似文献
198.
分别于2013年4月、8月、10月和2014年1月对南水北调东线水源核心区河流浮游植物群落结构、浮游植物密度进行调查,并利用多样性指数进行水质评价.区域共检出浮游植物5门34科67属118种,春秋两季物种数较多,夏冬两季物种数较少.优势种为蓝藻门小席藻( Phormidium.tenue)、绿藻门小球藻( Chlorella.pyrenoidosa)、硅藻门变异直链藻( Melosira.varians).区域浮游植物密度为3.5 ×105 cells/L,Shannon-wiener指数为2.32,Margalef指数为1.06,Pielou均匀度指数为0.54,水质为寡污-中污水平. 相似文献
199.
以前三批29个国家"城市矿产"示范基地为研究对象,对示范基地的回收利用规模、重点项目覆盖范围、示范基地类型做了概括性梳理,总结了示范基地建设的成功经验,分析了妨碍示范基地健康发展的问题,并提出一些预测性意见,供行业同仁参考。 相似文献
200.
介绍了北斗卫星实时监控系统的概况、功能特点及应用分析,根据石油危化品运输增长的现状及企业安全生产的需要,阐明系统的实现对石油危化品运输过程中的生产安全监控和应急调度指挥有重大的实际意义。 相似文献