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181.
Foundations of Resilience Thinking   总被引:1,自引:0,他引:1  
Through 3 broad and interconnected streams of thought, resilience thinking has influenced the science of ecology and natural resource management by generating new multidisciplinary approaches to environmental problem solving. Resilience science, adaptive management (AM), and ecological policy design (EPD) contributed to an internationally unified paradigm built around the realization that change is inevitable and that science and management must approach the world with this assumption, rather than one of stability. Resilience thinking treats actions as experiments to be learned from, rather than intellectual propositions to be defended or mistakes to be ignored. It asks what is novel and innovative and strives to capture the overall behavior of a system, rather than seeking static, precise outcomes from discrete action steps. Understanding the foundations of resilience thinking is an important building block for developing more holistic and adaptive approaches to conservation. We conducted a comprehensive review of the history of resilience thinking because resilience thinking provides a working context upon which more effective, synergistic, and systems‐based conservation action can be taken in light of rapid and unpredictable change. Together, resilience science, AM, and EPD bridge the gaps between systems analysis, ecology, and resource management to provide an interdisciplinary approach to solving wicked problems. Fundamentos del Pensamiento sobre Resiliencia  相似文献   
182.
Efforts to tackle the current biodiversity crisis need to be as efficient and effective as possible given chronic underfunding. To inform decision-makers of the most effective conservation actions, it is important to identify biases and gaps in the conservation literature to prioritize future evidence generation. We used the Conservation Evidence database to assess the state of the global literature that tests conservation actions for amphibians and birds. For the studies in the database, we investigated their spatial and taxonomic extent and distribution across biomes, effectiveness metrics, and study designs. Studies were heavily concentrated in Western Europe and North America for birds and particularly for amphibians, and temperate forest and grassland biomes were highly represented relative to their percentage of land coverage. Studies that used the most reliable study designs—before-after control-impact and randomized controlled trials—were the most geographically restricted and scarce in the evidence base. There were negative spatial relationships between the numbers of studies and the numbers of threatened and data-deficient species worldwide. Taxonomic biases and gaps were apparent for amphibians and birds—some entire orders were absent from the evidence base—whereas others were poorly represented relative to the proportion of threatened species they contained. Metrics used to evaluate effectiveness of conservation actions were often inconsistent between studies, potentially making them less directly comparable and evidence synthesis more difficult. Testing conservation actions on threatened species outside Western Europe, North America, and Australasia should be prioritized. Standardizing metrics and improving the rigor of study designs used to test conservation actions would also improve the quality of the evidence base for synthesis and decision-making.  相似文献   
183.
氯贝酸(Clofibric acid, CA)是一种常见药品和个人护理品(PPCPs)类物质,在环境中具有持久性和稳定性.常规的水处理技术难以去除微量的CA,采用电催化氢化脱氯的方法可有效实现脱氯.本研究考察了CA初始浓度、工作电位、阴极液初始pH、反应温度、钯载量和电解质Na2SO4的浓度等多种因素对氯贝酸降解的影响.结果表明,CA的脱氯降解符合一级动力学方程,在工作电位为-0.85 V vs Ag/AgCl,钯负载量为0.20 mg·cm-2,Na2SO4浓度为10 mmol·L-1,初始阴极液pH为4.6,反应温度控制在303 K时,经过120 min的反应后,初始浓度为5 mg·L-1的CA降解率达98%.因此利用钯/泡沫镍电极电催化还原降解废水中的CA具有很大的应用潜力.  相似文献   
184.
陕西关中近40年春季旱涝分析   总被引:1,自引:0,他引:1  
朱爱荣  李兆元 《灾害学》1996,11(4):74-78
对关中近40a6站3~4月降水量进行了标准旱涝等级分析和谐波分析,得出风调雨顺年份少,旱涝年份多,有2~3a及20a的显著周期。研究发现埃尔尼诺、太阳黑子相对数、西太平洋副高综合指数与旱涝变化规律有很好的对应关系,并有很高的相关系数。  相似文献   
185.
ABSTRACT: Using a case study of the Yakima River Valley in Washington State, this paper shows that relatively simple tools can be used to forecast the impact of the El Niño phenomenon on water supplies to irrigated agriculture, that this information could be used to estimate the significantly shifted probability distribution of water shortages in irrigated agriculture during El Niño episodes, and that these shifted probabilities can be used to estimate the value of exchanges of water between crops to relieve some of the adverse consequences of such shortages under western water law. Further, recently devised water‐trading tools, while not completely free under western water law to respond to forecasted El Niño episodes (ocean circulation patterns), are currently being employed during declared drought to reduce the devastating effects of water shortages in junior water districts on high valued perennial crops. Additional institutional flexibility is needed to take full advantage of climate forecasting, but even current tools clearly could prove useful in controlling the effects of climate variability in irrigated agriculture. Analysis shows the significant benefit of temporarily transferring or renting water rights from low‐value to high‐value crops, based on El Niño forecasts.  相似文献   
186.
促进植物提取技术高效修复镍污染土壤的方法   总被引:2,自引:1,他引:1  
随着对重金属超富集植物研究的加深,用植物提取技术来改良镍污染土壤已逐步进入实用阶段。在此所探讨的提高此技术功效的方法基于2个方面:提高土壤溶液中镍的浓度,促进植物对镍的吸收;根据已了解的超富集的生理机制可能采取的一些措施。  相似文献   
187.
水厂抽水对乌什地震台体应变观测数据的干扰分析   总被引:1,自引:0,他引:1  
根据体应变的观测原理,从理论和实际观测中分析了水厂抽水对体应变观测分钟值曲线的影响及两者间的相关性.分析表明,应变观测值波动时间与抽水时间基本吻合,因此认为水厂抽水对体应变观测会造成一定程度的干扰.  相似文献   
188.
从某油污样品中分离、筛选出一株破乳菌株10#,经鉴定属芽孢杆菌属。该菌株对油田稳定O/W乳化液具明显的破乳效果。该菌株最佳培养条件为:温度30~35℃,pH7.0~7.5,生长时间48~72h,碳源为液体石蜡。该菌株在培养48h后具有明显而稳定的破乳效果,破乳活性部位为菌体。  相似文献   
189.
Raney Ni催化4-溴联苯加氢降解研究   总被引:3,自引:1,他引:2  
以4-溴联苯为模型化合物,研究在H2作氢源、RaneyNi作催化剂条件下4-溴联苯的加氢脱溴反应,并调查了溶剂、碱及温度对加氢脱溴的影响,以及不同催化剂的催化效果.结果表明:相比贵金属催化剂(Ru/C、Pt/C、Pd/C),RaneyNi价廉且有较高的催化活性,具有实际应用价值;有机溶剂中添加适量的水可显著促进加氢脱溴反应,在乙醇/水(V/V)=85/15的溶液中,仅30min4-溴联苯就可100%脱溴;而在纯乙醇中,反应60min,尚有10%的4-溴联苯没有降解.另外,碱(NaOH)的加入可明显提高催化剂的活性,n(NaOH)∶n(HBr)=1.1∶1时,仅需30min4-溴联苯就完全被RaneyNi催化加氢降解;而n(NaOH)∶n(HBr)=2∶1时,反应60min,只有约93%的4-溴联苯发生了加氢降解,因此,碱的加入量以超过其化学反应剂量10%为宜.在温和条件(30~45℃、常压约101kPa)下,RaneyNi可催化4-溴联苯完全脱溴产生联苯,同时,联苯作为重要的化工产品可回收再利用.由此可见,多相催化加氢脱溴有望发展成为控制和消减多溴二苯醚等持久性卤代有机污染物的绿色降解技术.  相似文献   
190.
B10铜镍合金与H62黄铜的电偶腐蚀及电绝缘研究   总被引:2,自引:0,他引:2  
主要研究了船舶海水系统中B10铜镍合金与H62黄铜间的电偶腐蚀性能及电绝缘控制方法。通过电位监测、极化曲线测试考察了两种材料的电偶腐蚀倾向;通过电偶腐蚀试验、SEM观察和EDS分析考察了试样的电偶腐蚀程度、微观腐蚀形貌和成分变化;通过串联不同阻值电阻的模拟电绝缘试验,测定了两材料偶合的电绝缘判据。结果表明,B10与H62黄铜间存在明显的电偶腐蚀倾向,直接偶连时H62黄铜发生严重的脱锌腐蚀。电绝缘技术是控制电偶腐蚀的有效措施之一,串联电阻大于等于20kΩ时,可基本消除B10与H62黄铜间的电偶腐蚀。  相似文献   
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