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191.
基于2011年5月和9月航次获取的大型底栖动物和环境数据,采用建立在功能摄食群上的摄食均匀度指数(the feeding evenness index,jFD)并辅以建立在群落结构指标上的多元AZTI海洋生物指数(Multivariate AZTI Marine Biological Index,M-AMBI)评价渤海湾生态质量状况.本研究将所有大型底栖动物划分为5个摄食群,但2个航次均未发现植食者.从物种丰富度的角度看,碎屑食者和肉食者占比最高;从栖息密度的角度看则是浮游生物食者占比最高,而杂食者则在上述两个指标中均占比最低.摄食均匀度指数值大都低于0.60,说明研究区大部分海域的大型底栖动物群落受到不同程度的干扰,生态环境质量较差,这可能与该海域所受到的人为干扰如陆源排污、围海造陆有关.与M-AMBI相比,二者指示的渤海湾生态质量状况基本一致,且均能敏感地响应渤海湾近岸河口至离岸海域的环境压力梯度.总体上来讲,jFD适用于评价渤海湾的生态质量状况.  相似文献   
192.
赵茜  高欣  张远  赵瑞  丁森  刘思思 《环境科学研究》2014,27(10):1150-1156
为了解广西红水河流域大型底栖动物群落结构状况,于2013年春季(4月)、夏季(7月)、秋季(11月)对红水河流域13个采样点进行了调查. 采集并鉴定出大型底栖动物179个分类单元,隶属7纲20目66科. 其中水生昆虫种类数所占比例最高(79.3%),软体动物次之(15.1%). 各季节大型底栖动物个体数表现为夏季>春季>秋季. 依据大型底栖动物群落组成相似性,利用聚类分析将13个采样点分为2组. 组1采样点主要分布于岩滩水库和红水河干流,组2采样点主要分布于各个支流,2组采样点在无度量多维标定排序轴上分布差异明显. 指示种分析结果显示,组1指示种为马速达多足摇蚊(Polypedilum masudai),组2指示种以宜兴似动蜉(Cinygmina yixingensis)敏感物种为主. 功能摄食类群研究结果表明,红水河大型底栖动物以刮食者占绝对优势,其个体数占总个体数的比例为36.45%,撕食者(6.15%)和杂食者(3.25%)所占比例较小. 单因素方差分析结果显示,其他类(包括软甲纲、蛭纲以及蜱螨亚纲)和捕食者相对丰度存在季节性差异(P<0.05). T检验结果表明,收集者、捕食者和杂食者存在组间差异(P<0.05).   相似文献   
193.
广西贝江大型底栖动物群落结构时空分布特征   总被引:1,自引:0,他引:1  
为了解贝江大型底栖动物群落结构特征并对其水质进行生物学评价,于2015年1、8月对贝江流域17个采样点进行了调查,共采集大型底栖动物146个分类单元,隶属于8纲20目52科,其中昆虫纲所占比例最高(86.99%),软体动物次之(6.16%)。贝江底栖动物群落结构存在季节性差异,群落数量特征和结构复杂性均表现为冬季夏季。无度量多维标定排序和ANOSIM分析发现,贝江流域冬季和夏季底栖动物群落组成存在显著差异(r=0.26,P0.001)。群落相似性分析表明,贝江底栖动物存在显著的空间差异,整个流域可以分为2组,组1基本分布在自然河段,组2主要包括电站采样点和贝江下游采样点,各组间差异显著(P0.01)。底栖动物功能摄食类群以集食者(55%)和撕食者为主(16%),其次为滤食者(14%)和捕食者(11%),刮食者(4%)所占比例较小。水质评价结果显示,Shannon-Wiener生物多样性指数(H′)评价贝江水质为轻污-清洁。Hilsenhoff生物指数(BI)评价贝江流域水质属于清洁,与实际水质情况最接近。总体上,贝江流域自然河段底栖动物群落结构复杂多样,整体水质清洁。  相似文献   
194.
Choice of stakeholder groups and members in multicriteria decision models   总被引:4,自引:0,他引:4  
Simplistic economic objectives such as maximisation of producer profits are of little relevance in generating information to assist in the management of natural resources beyond the individual firm level. To provide data and information to support decision-making in natural resource management, it is necessary to take into account the views of various stakeholder groups and the multiple objectives of each group, through the use of some form of multicriteria analysis (MCA). Important decisions arise in the choice of stakeholder, since this will influence the management advice generated. Many groups and individuals can be affected by resource management decisions, but it would be impractical to attempt to identify the objectives and estimate their importance for each group. Also, questions arise concerning whether or not to include government agencies (which represent the broader community) and researchers as stakeholders. A further issue concerns choosing representative samples of stakeholder groups, from which to obtain preference data. Discussions with modellers and a reading of the literature would suggest that the choice of stakeholder groups and representatives is conducted haphazardly and is perhaps biased, and that a more systematic approach is needed. This article explores the above issues with reference to a number of multicriteria analyses, including local studies.  相似文献   
195.
活性炭表面酸性含氧官能团对吸附甲醛的影响   总被引:1,自引:0,他引:1  
利用Bothem滴定法测定了化学浸渍处理的活性炭表面酸性含氧官能团浓度,研究表面酸性含氧官能团对甲醛吸附的效应。结果表明,HNO3浸渍处理能有效增大活性炭表面的羧基、酚羟基和内酯基浓度;H2O2浸渍处理主要增大了活性炭表面的酚羟基浓度;随着NaOH浓度的增大,活性炭表面的酚羟基、内酯基和羰基浓度大致呈先增大后减小的趋势,这是由于NaOH的化学清洗作用和酸碱中和反应所致;HNO3浸渍处理的活性炭表面的酸性含氧官能团浓度显著超过NaOH、H2O2浸渍处理的活性炭,而30%(质量分数)NaOH浸渍处理的活性炭和30%(体积分数)H2O2浸渍处理的活性炭吸附甲醛的饱和时间比HNO3浸渍处理的活性炭吸附甲醛最大饱和时间分别多4.0、1.5 h,说明酚羟基能够显著影响活性炭吸附甲醛的效果。  相似文献   
196.
A new anaerobic reactor, Jet-loop anaerobic fluidized bed (JLAFB), was designed for treating high-sulfate wastewater. The treatment characteristics, including the effect of influent COD/SO42 ratio and alkalinity and sulfide inhibition in reactors, were discussed for a JLAFB and a general anaerobic fiuidized bed (AFB) reactor used as sulfate-reducing phase and methane-producing phase, respectively, in two-phase anaerobic digestion process. The formation of granules in the two reactors was also examined. The results indicated that COD and sulfate removal had different demand of influent COD/SO4^2- ratios. When total COD removal was up to 85%, the ratio was only required up to 1.2, whereas, total sulfate removal up to 95% required it exceeding 3.0. The alkalinity in the two reactors increased linearly with the growth of influent alkalinity. Moreover, the change of influent alkalinity had no significant effect on pH and volatile fatty acids (VFA) in the two reactors. Influent alkalinity kept at 400-500 mg/L could meet the requirement of the treating process. The JLAFB reactor had great advantage in avoiding sulfide and free-H2S accumulation and toxicity inhibition on microorganisms. When sulfate loading rate was up to 8. 1 kg/(m^3.d), the sulfide and free-H2S concentrations in JLAFB reactor were 58.6 and 49.7 mg/L, respectively. Furthermore, the granules, with offwhite color, ellipse shape and diameters of 1.0-3.0 mm, could be developed in JLAFB reactor. In granules, different groups of bacteria were distributed in different layers, and some inorganic metal compounds such as Fe, Ca, Mg etc. were found.  相似文献   
197.
This paper describes a four-year programme of “action research” (AR) undertaken with six communities in the UK, referred to as the Evaluating Low-Carbon Communities (EVALOC) project. The research combined a programme of research events with phased household-level monitoring of energy and carbon-reduction interventions. The carbon-reduction interventions were funded by the UK’s Department of Energy and Climate Change prior to the onset of the research. AR has recently been adopted within the context of environmental behaviour change programmes in the UK, with a number of methodological challenges. The EVALOC project’s challenges included developing a collaborative research design; building reciprocity between the researchers and research participants; dealing with biases and burdens in the research process; ensuring analytical rigour in the interpretation of the primarily qualitative evidence and dealing with the long-term and process-driven outcomes that arise from such interactions. This paper explores and discusses the challenges of AR in relation to selected research outcomes from EVALOC. We conclude by suggesting that the AR approach has helped to build capacity in the participating low-carbon communities (LCCs), through supporting the design, delivery and evaluation of their energy and carbon-reduction activities.  相似文献   
198.
Studies of advanced capitalist societies have shown that relatively wealthy localities with organized environmental groups are able to avoid unattractive facilities. The aim of this article is to ask whether the same logic applies in Hungary, a middle-income ‘transition’ society. The focus is not on the formal legal powers of local governments but on some of the influences on local government environmental policy. Drawing on a survey of mayors, notaries and environmental officials in 600 local government units in Hungary (from Budapest to villages), it explores the relation between environmental group mobilization, environmental group influence and environmental policy. It is shown that there are systematic differences in environmental group mobilization between settlements of different types, and that these differences, together with differences in local economic situation, explain the differing levels of perceived influence of environmental groups on policy. The localities where perceived environmental group influence is greatest are identified and shown to be places where there are higher education institutions and a tradition of ‘civic culture’, or where the local government is using the environment as an asset as part of an economic development strategy. It is concluded that similar processes to those found in advanced capitalist societies exist in Hungary. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
199.
The strength of networks: the local NGO response to the tsunami in India   总被引:1,自引:0,他引:1  
Kilby P 《Disasters》2008,32(1):120-130
This paper examines the role played by a network of 12 local non-governmental organisations (NGOs)--the East Coast Development Forum (ECDF)-in the response to the Indian Ocean tsunami ('Asian tsunami') of 26 December 2004, which devastated the east coast of India. It examines how the ECDF sought to meet the needs of affected people through a direct relief programme, a rehabilitation programme focused on the restoration of livelihoods, and through advocacy to press for changes to government programmes to make them inclusive and to ensure that they satisfy the priority needs of the people most affected. The paper concludes that it was the trust and capacity built up through past network activities of the fisher, dalit, and tribal communities that enabled the ECDF to launch an effective response to the tsunami. A lesson to emerge is that the use of similar existing networks could be employed in other disaster responses around the world.  相似文献   
200.
The adsorption kinetics for model pollutants on activated carbon fiber (ACF) by polarization was investigated in this work. Kinetics data obtained for the adsorption of these model pollutants at open-circuit, 400 mV, and −400 mV polarization were applied to the Lagergren equation, and adsorption rate constants (K a) were determined. With the anodic polarization of 400 mV, the capacity of sodium phenoxide was increased from 0.0083 mmol/g at open-circuit to 0.18 mmol/g, and a 17-fold enhancement was achieved; however, the capacity of p-nitrophenol was decreased from 2.93 mmol/g at open-circuit to 2.65 mmol/g. With the cathodal polarization of −400 mV, the capacity of aniline was improved from 3.60 mmol/g at open-circuit to 3.88 mmol/g; however, the capacity of sodium dodecylbenzene sulfonate was reduced from 2.20 mmol/g at open-circuit to 1.59 mmol/g. The enhancement for electrosorption changed with different groups substituting. Anodic polarization enhances the adsorption of benzene with the electron-donating group. But whether anodic or not, cathodal polarization had less effect on the adsorption of electron-accepting aromatic compounds, and decreased the adsorption capacity of benzene-bearing donor-conjugate bridge-acceptor, while increasing its adsorption rate. Electrostatic interaction played a very important role in the electrosorption of ion-pollutants. Translated from Environmental Science, 2006, 27(6): 1111–1116 [译自: 环境科学]  相似文献   
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