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841.
Species shift their distribution in response to climate and land-cover change, which may result in a spatial mismatch between currently protected areas (PAs) and priority conservation areas (PCAs). We examined the effects of climate and land-cover change on potential range of gibbons and sought to identify PCAs that would conserve them effectively. We collected global gibbon occurrence points and modeled (ecological niche model) their current and potential 2050s ranges under climate-change and different land-cover-change scenarios. We examined change in range and PA coverage between the current and future ranges of each gibbon species. We applied spatial conservation prioritization to identify the top 30% PCAs for each species. We then determined how much of the PCAs are conserved in each country within the global range of gibbons. On average, 31% (SD 22) of each species’ current range was covered in PAs. PA coverage of the current range of 9 species was <30%. Nine species lost on average 46% (SD 29) of their potential range due to climate change. Under climate-change with an optimistic land-cover-change scenario (B1), 12 species lost 39% (SD 28) of their range. In a pessimistic land-cover-change scenario (A2), 15 species lost 36% (SD 28) of their range. Five species lost significantly more range under the A2 scenario than the B1 scenario (p = 0.01, SD 0.01), suggesting that gibbons will benefit from effective management of land cover. PA coverage of future range was <30% for 11 species. On average, 32% (SD 25) of PCAs were covered by PAs. Indonesia contained more species and PCAs and thus has the greatest responsibility for gibbon conservation. Indonesia, India, and Myanmar need to expand their PAs to fulfill their responsibility to gibbon conservation. Our results provide a baseline for global gibbon conservation, particularly for countries lacking gibbon research capacity.  相似文献   
842.
● Methods for estimating the aging of environmental micro-plastics were highlighted. ● Aging pathways & characterization methods of microplastics were related and reviewed. ● Possible approaches to reduce the contamination of microplastics were proposed. ● The prospect and deficiency of degradable plastics were analyzed. With the increasing production of petroleum-based plastics, the problem of environmental pollution caused by plastics has aroused widespread concern. Microplastics, which are formed by the fragmentation of macro plastics, are bio-accumulate easily due to their small size and slow degradation under natural conditions. The aging of plastics is an inevitable process for their degradation and enhancement of adsorption performance toward pollutants due to a series of changes in their physiochemical properties, which significantly increase the toxicity and harm of plastics. Therefore, studies should focus on the aging process of microplastics through reasonable characterization methods to promote the aging process and prevent white pollution. This review summarizes the latest progress in natural aging process and characterization methods to determine the natural aging mechanism of microplastics. In addition, recent advances in the artificial aging of microplastic pollutants are reviewed. The degradation status and by-products of biodegradable plastics in the natural environment and whether they can truly solve the plastic pollution problem have been discussed. Findings from the literature pointed out that the aging process of microplastics lacks professional and exclusive characterization methods, which include qualitative and quantitative analyses. To lessen the toxicity of microplastics in the environment, future research directions have been suggested based on existing problems in the current research. This review could provide a systematic reference for in-depth exploration of the aging mechanism and behavior of microplastics in natural and artificial systems.  相似文献   
843.
● China has pledged ambitious carbon peak and neutrality goals for mitigating global climate change. ● Major challenges to achieve carbon neutrality in China are summarized. ● The new opportunities along the pathway of China’s carbon neutrality are discussed from four aspects. ● Five policy suggestions for China are provided. China is the largest developing economy and carbon dioxide emitter in the world, the carbon neutrality goal of which will have a profound influence on the mitigation pathway of global climate change. The transition towards a carbon-neutral society is integrated into the construction of ecological civilization in China, and brings profound implications for China’s socioeconomic development. Here, we not only summarize the major challenges in achieving carbon neutrality in China, but also identify the four potential new opportunities: namely, the acceleration of technology innovations, narrowing regional disparity by reshaping the value of resources, transforming the industrial structure, and co-benefits of pollution and carbon mitigation. Finally, we provide five policy suggestions and highlight the importance of balancing economic growth and carbon mitigation, and the joint efforts among the government, the enterprises, and the residents.  相似文献   
844.
● A novel framework integrating quantile regression with machine learning is proposed. ● It aims to identify factors driving observations to upper boundary of relationship. ● Increasing N:P and TN concentration help fulfill the effect of TP on CHL. ● Wetter and warmer decrease potential and increase eutrophication control difficulty. ● The framework advances applications of quantile regression and machine learning. The identification of factors that may be forcing ecological observations to approach the upper boundary provides insight into potential mechanisms affecting driver-response relationships, and can help inform ecosystem management, but has rarely been explored. In this study, we propose a novel framework integrating quantile regression with interpretable machine learning. In the first stage of the framework, we estimate the upper boundary of a driver-response relationship using quantile regression. Next, we calculate “potentials” of the response variable depending on the driver, which are defined as vertical distances from the estimated upper boundary of the relationship to observations in the driver-response variable scatter plot. Finally, we identify key factors impacting the potential using a machine learning model. We illustrate the necessary steps to implement the framework using the total phosphorus (TP)-Chlorophyll a (CHL) relationship in lakes across the continental US. We found that the nitrogen to phosphorus ratio (N׃P), annual average precipitation, total nitrogen (TN), and summer average air temperature were key factors impacting the potential of CHL depending on TP. We further revealed important implications of our findings for lake eutrophication management. The important role of N׃P and TN on the potential highlights the co-limitation of phosphorus and nitrogen and indicates the need for dual nutrient criteria. Future wetter and/or warmer climate scenarios can decrease the potential which may reduce the efficacy of lake eutrophication management. The novel framework advances the application of quantile regression to identify factors driving observations to approach the upper boundary of driver-response relationships.  相似文献   
845.
针对目前电子废弃物中持久性有机污染物(POPs)尚未形成有效快速分析检测方法的问题,介绍了溶剂萃取、固相萃取、微波萃取和超临界流体萃取等POPs前处理技术的研究进展,总结了POPs的分析方法,如:气相色谱、液相色谱、气相色谱-质谱法、高分辨率气相色谱-高分辨质谱法等化学分析方法,以及生物传感器测定法、表面胞质团共振检测法、酶联免疫检测法等生物分析方法。分析了各方法的优劣,并提出了展望。  相似文献   
846.
南海东北部考洲洋海洋渔业环境质量评价   总被引:4,自引:2,他引:2  
根据1999年考洲洋12个调查站的观测资料,按我国有关的环境质量标准,用质量指数法分级评价考洲洋的环境质量。结果表明:考洲洋的环境质量总体较好,但轻微污染偶有发生,石油类是主要污染物,其次为PO4-P。2月(枯水期)在5测站的表层沉积物中有机质含量略有超标,3测站海水和2测站表层沉积物受石油类轻污染,1测站的海水受Cu轻污染。8月(丰水期),5测站的海水受PO4-P轻污染。  相似文献   
847.
开展水生昆虫生长过程研究对掌握研究区域水生生物的生物学特征和研究区域生态环境状况等均具有重要作用,可为构建和完善研究区域河流生态环境保护体系提供科学参考。于2017年逐月对香溪河库湾入库支流(螃蟹溪)中的一种水生昆虫——麦氏花翅蜉(Baetiella macani)的种群进行了研究,基于大小频率法、幼虫期有效积温条件进行了生活史性状分析和验证。结果显示:麦氏花翅蜉为三化性昆虫,包含一个冬季世代和两个夏季世代。冬季世代幼虫的发育历期为3~4个月,所需有效积温为1 286 ℃;夏季世代幼虫的发育历期为1~2个月,所需有效积温为757 ℃。研究结果丰富了中国地区水生昆虫的生活史性状信息,并首次呈现了花翅蜉属的生活史特征。  相似文献   
848.
城市路面积尘微塑料污染特征   总被引:4,自引:3,他引:1  
微塑料作为一种新兴污染物,由于其对生态系统具有潜在的负面影响,受到了广泛的关注.但是目前关于其在陆地环境中,尤其是路面积尘中的相关信息相对有限.本文对马鞍山市雨山区路面积尘的微塑料污染特征进行了研究.研究区域内单位面积路面所积累的微塑料丰度为(18.11±32.36)n·m-2,含量为(27.29±72.64)mg·m...  相似文献   
849.
青海玉树7.1级地震震害特点分析及启示   总被引:7,自引:1,他引:6  
根据2010年4月14日玉树7.1级地震震害现场调查资料,对其震害特点进行了全面的分析总结,阐述了震区环境及其地质构造背景,对断层效应及场地效应等也进行了分析,并归纳总结了防震减灾的经验与启示。  相似文献   
850.
张勤  高亦飞  高娜  蒋春花  王宝坤  郭建素  贾军鹏 《灾害学》2010,25(3):130-134,144
社区地震应急工作是我国地震应急管理工作的重要内容之一,是减轻地震灾害的有效途径。如何依托社区开展地震应急工作是近年来,特别是汶川地震后全社会关注的问题。从地震应急组织管理、应急预案、志愿者队伍建设、宣传培训、应急演练、物资储备、避难场地和疏散通道设置以及地震应急处置等几个方面讨论了社区地震应急工作模式。  相似文献   
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