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351.
挺水植物生物炭对硫丹的吸附及催化水解作用 总被引:2,自引:0,他引:2
以美人蕉、菖蒲、芦苇、茭白、再力花、芦竹等挺水植物为原料,在限氧升温(550℃)条件下制备6种不同性质的生物炭,研究其组成及结构对硫丹吸附和催化水解作用.结果表明:550℃下热解,湿地植物生物炭所含灰分高于一般农产品废弃物,介于10.88%~31.11%间.生物炭表面芳香类官能团较多,孔隙部分呈碎片化,以介孔为主.6种生物炭对硫丹都具良好吸附性能.吸附行为主要发生在含致密有机质的生物炭表面,包括疏水、扩散及分配作用等.中/碱性条件下,美人蕉生物炭、菖蒲生物炭及再力花生物炭能有效去除水溶液中的硫丹,去除率为96.77%~98.57%.中性条件下,因生物炭对硫丹的催化,对硫丹的去除率提高约16.57%~72.57%. 相似文献
352.
In order to study the differences in algae species and their biomass in water bodies in a region, three reservoirs and two lakes at the center of Guanzhong Plain were chosen to identify algae functional groups, measure biomass, and assess water quality, from January2013 to December 2014. The water bodies represented different trophic levels: one oligotrophic, three mesotrophic, and one eutrophic. Based on the Reynolds' functional groups, they had 10 groups in common—B, P, D, X1, M, MP, F, S1, J, and G, but the algae biomasses and proportions were different. In the oligotrophic reservoir, functional group B reached a peak biomass of 576 × 10~4 L~(-1), which accounted for 31.27%. In the eutrophic lake,functional group D reached a peak biomass of 3227 × 10~4 L~(-1), which accounted for only13.38%. When samples collected from other water bodies with similar trophic levels were compared, we found differences in the algae species functional groups. The potential reasons for the differences in algae functional group characteristics in the different water bodies in the region were water temperature and nutritional states. 相似文献
353.
论述了建立环境集团诉讼制度的必要性、基本慨念、特征和诉讼程序中的几个问题,并对我国建立该项制度提出了一些探讨性建议。 相似文献
354.
资源科学的学科体系——关于资源科学学科建设的研讨 总被引:5,自引:3,他引:5
作者认为当代全球日趋严重的资源问题,尤其自然资源方面的问题,重要原因之一是缺乏具有整体理念的现代资源科学理论的引导。因此,发展与建设综合性的现代资源科学的学科群,具有理论与实践的双重意义。为此,作者在阐明什么是资源科学的基础上,对资源科学及其三维网络结构的学科体系进行了探讨,即资源科学包括总论、各论及区域分论三大部分,它们组成资源科学完整的学科体系,并派生出众多的分支学科,构成综合的现代资源科学的学科群。从而为发展资源科学,改进资源管理及改革资源科学教育提供依据。 相似文献
355.
论江汉湖群湿地的环境保护 总被引:4,自引:0,他引:4
湖泊水质恶化警示着湖泊生态系统受到损害 ,影响湖泊湿地功能的发挥 ,利用 1999年~ 2 0 0 0年江汉湖群监测结果 ,对其水质现状进行评价 ;分析江汉湖群湿地的环境污染问题 ,提出对江汉湖群湿地水体功能恢复的对策 相似文献
356.
357.
沈雪梅 《防灾技术高等专科学校学报》2005,7(3):108-110,32
加强干部队伍监督管理是高校组织工作的一个重要方面,群众监督将发挥其无法替代的作用。本文对高校干部队伍监督管理的目标、内容、重点,以及在高校干部管理中的特点及难点作了分析,对完善领导干部监督机制,特别是对其中的群众监督的实践进行了深入思考和探索。 相似文献
358.
359.
Evaluating and Ranking the Vulnerability of Global Marine Ecosystems to Anthropogenic Threats 总被引:3,自引:0,他引:3
BENJAMIN S. HALPERN§ KIMBERLY A. SELKOE† FIORENZA MICHELI‡ CARRIE V. KAPPEL‡ 《Conservation biology》2007,21(5):1301-1315
Abstract: Marine ecosystems are threatened by a suite of anthropogenic stressors. Mitigating multiple threats is a daunting task, particularly when funding constraints limit the number of threats that can be addressed. Threats are typically assessed and prioritized via expert opinion workshops that often leave no record of the rationale for decisions, making it difficult to update recommendations with new information. We devised a transparent, repeatable, and modifiable method for collecting expert opinion that describes and documents how threats affect marine ecosystems. Experts were asked to assess the functional impact, scale, and frequency of a threat to an ecosystem; the resistance and recovery time of an ecosystem to a threat; and the certainty of these estimates. To quantify impacts of 38 distinct anthropogenic threats on 23 marine ecosystems, we surveyed 135 experts from 19 different countries. Survey results showed that all ecosystems are threatened by at least nine threats and that nine ecosystems are threatened by > 90% of existing threats. The greatest threats (highest impact scores) were increasing sea temperature, demersal destructive fishing, and point-source organic pollution. Rocky reef, coral reef, hard-shelf, mangrove, and offshore epipelagic ecosystems were identified as the most threatened. These general results, however, may be partly influenced by the specific expertise and geography of respondents, and should be interpreted with caution. This approach to threat analysis can identify the greatest threats (globally or locally), most widespread threats, most (or least) sensitive ecosystems, most (or least) threatened ecosystems, and other metrics of conservation value. Additionally, it can be easily modified, updated as new data become available, and scaled to local or regional settings, which would facilitate informed and transparent conservation priority setting. 相似文献
360.
Dirk Semmann Hans-Jürgen Krambeck Manfred Milinski 《Behavioral ecology and sociobiology》2005,57(6):611-616
To find conditions under which humans cooperate within groups of unrelated individuals has been of major interest in the behavioral sciences. The experimental paradigm for studying potential cooperation in social dilemmas is the public goods game. Here humans regularly fail to sustain a public resource cooperatively. However, the need to maintain good reputation for other social interactions, such as indirect reciprocity, has been identified as an effective mechanism to sustain cooperation in public goods situations. As a side effect of building a good reputation through cooperative actions, an individual provides direct benefits to members of his/her own social group. These benefits could be an incentive to reward a good reputation of group members. Here we show experimentally that building a good reputation through cooperative behavior in a public goods situation is rewarded in future social interactions, not only within ones own social group but also, at a similar level, in other social groups: humans regard cooperative behavior of others as an honest signal irrespective of past direct personal benefits. Reputation gained within as well as outside ones own social group can be a driving force for selfish individuals to cooperate in public goods situations, and thereby sustain any public resource.Communicated by T. Czeschlik 相似文献