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201.
贵州高原三板溪水库浮游植物功能群时空分布特征   总被引:9,自引:0,他引:9  
为探究贵州高原三板溪水库的浮游植物功能群时空分布特征,于2012—2013年枯水期(11月)、平水期(4月)、丰水期(7月)对三板溪水库浮游植物与水样进行分层采样分析.研究结果表明,水库浮游植物可分为21个功能群,其优势功能群具有明显的水期分布特征:枯水期P+X1+D+J→平水期P+B+C+G→丰水期M+H1+S1+J,垂直分布中平水期和丰水期优势功能群在10 m左右发生变化,枯水期在70 m处变化;各时期水体热分层及营养物质分布差异是产生该特征的主要原因;浮游植物功能群时空分布特征受环境变化影响,水温、p H和N/P变化是浮游植物功能群结构变化的最主要因素;浮游植物功能群生长策略变化规律为:枯水期CR/C/S策略藻种→平水期R/CR/CS策略藻种→丰水期S/CS/CR/R策略藻种;通过浮游植物功能群与生境之间的相互关系可以得出:三板溪水库水体处于富营养状态.  相似文献   
202.
小球藻对多种重金属吸附性能的研究   总被引:1,自引:0,他引:1  
微藻是一种广泛存在、生长速度快、适宜大规模养殖的结构简单的植物.近年来,基于微藻的水污染控制技术被广泛研究并得到认可,其中,利用藻类吸附污染水体中的重金属类物质更被看作是一种极具前景的水处理手段.然而,当前的研究始终对藻类吸附重金属性能的决定性影响因素缺乏相对全面的探究,同时对藻类表面官能团在吸附过程中所起的作用也不明确.对此,本研究采取静态实验的方法,选取常见的淡水藻类小球藻Chlorella sp.和典型重金属Ni (Ⅱ)、Cr (VI)、Cd (Ⅱ),以藻细胞密度、重金属离子浓度、温度、pH作为影响因素,探究其对小球藻细胞吸附性能的影响.结果表明,小球藻对Ni (Ⅱ)、Cr (VI)、Cd (Ⅱ)均显示出了很好的吸附能力.在所选的几种藻细胞密度下,小球藻吸附性能差异不大.当溶液处于中性偏酸性、重金属浓度低于5 mg·L-1的情况下,小球藻吸附效果最好.在20~30℃范围内升高温度对吸附会产生有利影响.对小球藻进行红外光谱检测发现,官能团C—O、C=O、—COOH、—NH—在对重金属离子的吸附过程中起主要作用.  相似文献   
203.
文建龙  黄立平 《四川环境》2007,26(1):118-121
从自然和社会两个角度来划分,可以把生态灾害划分为自然性生态灾害和社会性生态灾害。生态灾害与弱势群体有一定的关联:生态灾害会催生灾害性弱势群体;由于弱势群体在社会系统中总是处在相对恶劣的环境之中,也缺乏必要的资源保护自己,在发生生态灾害时,弱势群体往往最受损害。需要用科学发展观指导环境生态建设,也要在建设生态文明的视角下加大保护弱势群体的力度。  相似文献   
204.
Integrated assessment (IA) can be defined as a structured process of dealing with complex issues, using knowledge from various scientific disciplines and/or stakeholders, such that integrated insights are made available to decision makers (J. Rotmans, Enviromental Modelling and Assessment 3 (1998) 155). There is a growing recognition that the participation of stakeholders is a vital element of IA. However, only little is known about methodological requirements for such participatory IA and possible insights to be gained from these approaches. This paper summarizes some of the experiences gathered in the ULYSSES project, which aims at developing procedures that are able to bridge the gap between environmental science and democratic policy making for the issue of climate change. The discussion is based on a total of 52 IA focus groups with citizens, run in six European and one US city. In these groups, different computer models were used, ranging from complex and dynamic global models to simple accounting tools. The analysis in this paper focuses on the role of the computer models. The findings suggest that the computer models were successful at conveying to participants the temporal and spatial scale of climate change, the complexity of the system and the uncertainties in our understanding of it. However, most participants felt that the computer models were less instrumental for the exploration of policy options. Furthermore, both research teams and participants agreed that despite considerable efforts, most models were not sufficiently user-friendly and transparent for being accessed in an IA focus group. With that background, some methodological conclusions are drawn about the inclusion of the computer models in the deliberation process. Furthermore, some suggestions are made about how given models should be adapted and new ones developed in order to be helpful for participatory IA. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
205.
Winter tourism and mountain agriculture are the most important economic sectors in a major part of the Swiss Alps. Both are highly sensitive to changing climatic conditions. In the framework of the CLEAR project, results from climate impact research in the field of tourism and agricultural production were used to investigate the perception of climatic change by stakeholders and to assess possible adaptations. We used a participatory integrated assessment (PIA) to involve the knowledge, values and experiences of the various social actors in tourism and agriculture (e.g., skiers, tourism managers, farmers) in the research process. Whereas climate change may have various severe direct impacts on the tourism industry, depending on the region, agricultural production may generally benefit from changed climatic conditions. But because of the dependence of farmers on “off-farm” income, the loss due to declining winter tourism in specific areas may cause more important indirect effects. However, the two sectors may adapt actively by choosing from a variety of strategies, and the loss of income from the tourism industry may support the re-evaluation of the various functions agriculture plays in mountain regions, beyond the production of food. The study demonstrates the suitability of the PIA approach to elucidate the interactions between different stakeholders and their perception of the climate change phenomena. A similar participatory approach could be a useful tool to transfer research results and expert knowledge to the political process addressing adaptations to climate change. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
206.
深圳水库群表层水中全氟化合物的分布特征   总被引:2,自引:4,他引:2  
为探究深圳市水库群表层水中全氟化合物(perfluorinated compounds,PFCs)的含量水平,应用WAX固相萃取分离富集与高效液相色谱-质谱联用相结合的方法,分析了2012年11月及2013年1月采自深圳12个水库库区中心与取水口共25个位点表层水中14种PFCs的含量及变化规律.结果表明全氟己烷磺酸(perfluorohexane sulfonate,PFHxS)及碳链≥11的长链PFCs均未检出,全氟辛酸(perfluorooctane acid,PFOA)为主要单体,库区中心和取水口ΣPFCs未见显著性差异;强降水对水库表层水PFCs有稀释作用,同时也可输入PFOA;水库群表层水PFCs含量主要受其进水口位置、水源环境及水库地理位置等因素的影响.虽水温与ΣPFCs含量间也有正相关关系,但影响作用弱于强降水.  相似文献   
207.
Two novel polymers (NJ-1 and N J-2) were synthesized by chemically modified a hypercrosslinked polymer NJ-0 with dimethylamine and trimethylamine, respectively. The comparison of the adsorption properties of the three polymers toward phenol, resorcin and phloroglucin was made. The study focused on the static equilibrium adsorption behaviors and the adsorption thermodynamics. Freundlich equation was found to fit the adsorption results well. The effect of amino groups introduced onto the surface of the resin and the structure of phenolic compounds on the adsorption were also studied. The hydrogen-bonding interaction and electrostatic interaction could happen between the amino groups and the adsorbates. The adsorption impetus increased as quantity of hydroxyl groups increased, but the adsorption capacity decreased due to the drop of the matching degree of the aperture of resins and the diameter of adsorbate molecules.  相似文献   
208.
三座不同营养类型水库春季细菌生理群分布特征   总被引:2,自引:0,他引:2  
运用实验室培养的方法,于2005年4月调查了热带亚热带过渡区的三座不同营养类型的水库:大镜山(富营养型),梅溪(贫中营养型),流溪河(贫中营养型),并对3座水库水体和底泥异养细菌及N、P细菌生理群的分布特点进行了初步分析。3座水库水体和底泥细菌生理群的分布差异明显,这些差异主要取决于水库水体和底泥的营养状况。大镜山水库和流溪河水库底泥中有机营养物质丰富,2座水库底泥中主要细菌生理群的分布相似。流溪河水库与梅溪水库为贫中营养型水库,两座水库水体中主要细菌生理群的密度分布相近。在流溪河水库和大镜山水库中不同采样点之间细菌生理群的分布存在一定的空间差异,梅溪水库大坝和出水口之间差异不显著,这种差异取决与水库的水动力学特征。3座水库水体硝酸还原菌与TP(R2=0.6668,P<0.05)和Chl.a(R2=0.6734,P<0.05)以及有机磷分解菌与TP(R2=0.5977,P<0.05)和Chl.a(R2=0.5968,P<0.05)之间存在着显著的相关关系。  相似文献   
209.
张怡  胡韧  肖利娟  韩博平 《生态环境》2012,21(1):107-117
南屏、竹仙洞水库是珠海市拱北水厂的水源地,也是对澳门供水的主要水库。于2010年4月-2011年3月对这两座水库逐月采样,依据Padisák等(2009)功能类群方法对水样中浮游植物进行分类,不同的功能类群以不同的字母或字母与数字组合来命名。并结合水库的水文、水质及浮游植物生境特征,分析优势功能类群的演替动态及其主要环境影响因子。结果表明:南屏水库浮游植物功能类群演替具有明显的时间异质性。泽丝藻(Limnothrix sp.)、假鱼腥藻(Pseudanabaena sp.)等丝状蓝藻代表的S1功能类群与薄甲藻(Glenodinium sp.)代表的Y功能类群在6、7月份相对稳定水体中共同占优势,是南屏水库丰水期浮游植物演替的一个重要特征;而枯水期则主要以小环藻(Cyclotella sp.)、针杆藻(Synedra sp.)、颗粒直链藻(Aulacoseira granulata)等适应混合水体的C+D+P功能类群为优势群落。竹仙洞水库中几乎全年以C+D+P功能类群占优势,推测是因为竹仙洞水库水力滞留时间较短,利于耐冲刷的功能类群的生长。通过PCA(主成分分析)和RDA(冗余分析)探讨浮游植物功能类群演替与环境因子之间的关系,结果显示水力滞留时间、降雨量和正磷是影响南屏水库浮游植物功能类群演替的重要因子,而竹仙洞水库则是水力滞留时间和降雨量。两座水库的水力滞留时间差异明显,从而造成两座水库浮游植物功能类群组成及演替趋势的不同。  相似文献   
210.
Although international trade in energy may offer a flexible and cost effective means by which European countries could meet their renewable energy targets, developers in the exporting nation can face local opposition for reasons which are not always clear. Using focus groups and a public survey, we contrast perspectives between local stakeholders and wind farm operators and investigate the community impacts associated with large-scale wind energy for domestic use and export from Ireland to the UK. Although the export of renewable energy from Ireland to the UK is currently on hold, our findings suggest that significant investment is required by the state and wind farm operators in better information provision, trust building, effective instruments to internalise wind farm externalities and co-management arrangements before Ireland can fully capture the benefits of wind exports to the UK.  相似文献   
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