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151.
聂文东  刘学敏  张杰平  汪明  王若嘉 《灾害学》2011,26(1):133-137,143
通过对2009年11月12日在四川省广元市三堆镇马口村举行的自然灾害应急演练进行初步的分析研究,总结出了从前期准备、正式实施到演练评估的农村社区自然灾害应急演练基本流程和方法。在马口村自然灾害应急演练的前期准备阶段,根据当地实际情况选择了滑坡、泥石流为演练的自然灾害背景,制定了3级响应演练模式,并细化了各级响应的启动标准。在演练的正式实施阶段,采用了参与式的演练方案设计方法,充分调动了当地群众的积极性。演练结束后在现场发放调查问卷,对演练进行了多方面、多角度的评估,演练基本达到了预定目标。  相似文献   
152.
Land-use change due to socioeconomic factors leads to the abandonment of traditional intensive coppice management in large areas of the mountainous landscapes of the Apennines (Italy). In this study we explored the multivariate relationship between plant species traits, stage of forest succession and environmental gradients. We focused on community-level patterns in plant traits of the vegetation of beech forest understory along the regeneration chronosequence initiated after cessation of coppicing. We hypothesized that the correlations between the traits and environmental factors should increase with succession age due to the decreasing role of chance.Landscape-level heterogeneity, i.e. changing elevation, slope, exposition, bedrock and forest stand age was assessed using a stratified random sampling design. Sixty sites were sampled for stand structure and species composition. We focused on 14 plant traits related to persistence, growth and dispersal. The recently developed data-analytical method, Model-Based Recursive Partitioning, was used to disentangle the relationships between patterns of plant traits and environmental gradients.About half (seven) of the studied plant traits showed significant correlations with succession stand age, elevation, inclination, heat index and bedrock. Contrary to the low number of trait-environment correlations in early succession, eight traits showed significant relationships with one or more abiotic factors in older stages of the post-coppice development. Stand age had the highest independent explanatory power, explaining 40% of variance of SLA, more than 17% of variance of short-distance seed dispersal and more than 15% of variance of both long-term connection and extensive perennial root. Among the other abiotic factors, elevation explained 27% of variance of SLA, inclination explained 6-8% of variance of long-term connection, extensive perennial root, thickening and large bud bank.The observed trait-environmental relationship is assumed to be driven by various environmental factors operating at various levels of complexity. While forest succession in relatively homogeneous landscapes might be driven mainly by environmental factors related to forest succession itself and associated abiotic changes (such as changes in light and soil moisture patterns), in heterogeneous landscapes the succession pathways may be structured by landscape-level environmental factors such as inclination. However, in the present study, forest stand age had the highest explanatory power for most of the investigated traits, supporting the assumption of the overall strong impact of succession-driven environmental factors in trait-environment relationships.  相似文献   
153.
为控制污水管道产生的有害气体对管道设施和周围环境造成的不利影响,通过搭建带有搅拌的反应器系统,来模拟实际污水管道,探究脉冲通气对污水管道内有害气体的控制效果及生物群落变化的影响。研究表明:脉冲通气能有效控制有害气体的产生,在水流速度为0.2 m·s−1时,硫化氢(H2S)、甲烷(CH4)、一氧化碳(CO)的抑效果最好,其抑制率分别为98.7%,44.4%,92.5%;在脉冲通气作用下,古菌群落的生物多样性不断减少,细菌群落的生物多样性不断增加;同时,脉冲通气也改变了生物群落结构,其群落结构变化与气相参数的变化是相一致的。  相似文献   
154.
基于短程硝化处理后的老龄垃圾渗滤液,含有大量难降解有机污染物,且氨氮和化学需氧量浓度高,C/N比低等特点。本研究以厌氧硝化污泥作为接种污泥,采用升流式厌氧污泥床反应器(UASB),快速启动厌氧氨氧化反应,对其进行深度脱氮。探究启动厌氧氨氧化反应的最佳条件和脱氮性能,根据污泥形貌特征和微生物群落结构的变化,阐明厌氧氨氧化的作用机理。结果表明,厌氧氨氧化快速启动最佳条件:温度为(30±1) ℃、初始pH为7.5、NO2/NH4+为1.25~1.50、无外加碳源和MLSS为4 200 mg·L−1。历经60 d后,厌氧氨氧化成功启动,进水TN容积负荷最高为0.45 kg·(m3·d)−1,TN容积负荷去除速率最高为0.36 kg·(m3·d)-1,NH4+-N、NO2-N和TN去除率超过80%。同时,UASB运行至第60天时,接种污泥形貌呈现花椰菜结构,微生物群落多样性减少,Planctomycetes门为优势菌群,其丰度为44.4%。Candidatus Brocdia属为第一优势菌属,其丰度为42.8%,证实厌氧氨氧化快速启动成功,AnAOB利用NO2-N为电子受体,以NH4+-N为电子供体实现深度脱氮。综上所述,厌氧氨氧化的快速启动可为短程硝化处理后的老龄垃圾渗滤液深度脱氮提供参考。  相似文献   
155.
Abstract: The developing field of community genetics has the potential to broaden the contribution of genetics to conservation biology by demonstrating that genetic variation within foundation plant species can act to structure associated communities of microorganisms, invertebrates, and vertebrates. We assessed the biodiversity consequences of natural patterns of intraspecific genetic variation within the widely distributed Australian forest tree, Eucalyptus globulus. We assessed genetic variation among geographic races of E. globulus (i.e., provenances, seed zones) in the characteristics of tree‐trunk bark in a 17‐year‐old common garden and the associated response of a dependent macroarthropod community. In total, 180 macroarthropod taxa were identified following a collection from 100 trees of five races. We found substantial genetically based variation within E. globulus in the quantity and type of decorticating bark. In the community of organisms associated with this bark, significant variation existed among trees of different races in composition, and there was a two‐fold difference in species richness (7–14 species) and abundance (22–55 individuals) among races. This community variation was tightly linked with genetically based variation in bark, with 60% of variation in community composition driven by bark characteristics. No detectable correlation was found, however, with neutral molecular markers. These community‐level effects of tree genetics are expected to extend to higher trophic levels because of the extensive use of tree trunks as foraging zones by birds and marsupials. Our results demonstrate the potential biodiversity benefits that may be gained through conservation of intraspecific genetic variation within broadly distributed foundation species. The opportunities for enhancing biodiversity values of forestry and restoration plantings are also highlighted because such planted forests are increasingly becoming the dominant forest type in many areas of the world.  相似文献   
156.
This paper addresses the treatment of purified terephthalic acid (PTA) effluent using anaerobic and aerobic processes. Laboratory studies were carried out on flow proportionate composite wastewater generated from the manufacturing of PTA. An activated sludge process (ASP-two stage and single stage) and an upflow anaerobic fixed film fixed bed reactor (AFFFBR) were used, individually and in combination. The performance of a full-scale ETP under existing operating conditions was also studied. Full scale ETP studies revealed that the treatment of PTA effluent using a two-stage ASP alone does not meet treated effluent quality within the prescribed Indian Standards. The biomass produced in the two stage ASP was very viscous and fluffy and the sludge volume index (SVI) was very high (200-450 ml/g). However, pretreatment of PTA effluent using an upflow AFFFBR ensured substantial reduction in BOD (63%) and COD (62%) with recovery of biogas at 1.8-1.96 l/l effluent treated at a volumetric loading rate (VLR) 4-5 kg COD/m(3) d. The methane content in the biogas varied between 55% and 60%. The pretreated effluent from the upflow AFFFBR was then treated through a single stage ASP. The biomass produced in the ASP after anaerobic treatment had very good settlability (SVI: 75-90 ml/g) as compared to the two stage ASP and the treated effluent quality with respect to BOD, COD and SS was within the prescribed Indian Standards. The alternative treatment process comprising an upflow AFFFBR and a single stage ASP ensured net power saving of 257 kW and in addition generated 442 kW of power through the AFFFBR.  相似文献   
157.
- DOI: http://dx.doi.org/10.1065/espr2006.02.294 Background, Aim and Scope. To better address the requirements of the changing multilateral order, the United Nations Industrial Development Organization (UNIDO) Cleaner Production Programme, in 2004, developed the new Sustainable Industrial Resource Management (SIRM) approach. This approach is in accordance with the principles decided at the United Nations Conference on Environment and Development (UNCED) in Rio de Janeiro, Brazil in 1992. Unlike the traditional approaches to environmental management, the SIRM concept captures the idea of achieving sustainable industrial development through the implementation of circular material and energy flows in the entire production chain and reduction of the amount of material and energy used with greater efficiency solutions. The SIRM approach seeks to develop new models to encourage a shift from selling products to supplying services, modifying, in this manner, the supplier/user relationship and resulting in a win-win situation for the economy and the environment. Chemical Leasing represents such a new service-oriented business model and is currently being promoted by UNIDO′s Cleaner Production Programme. Main Features. One of the potential approaches to address the problems related to ineffective use and over-consumption of chemicals is the development and implementation of Chemical Leasing business models. These provide concrete solutions to the effective management of chemicals and on the ways negative releases to the environment can be reduced. The Chemical Leasing approach is a strategy that addresses the obligations of the changing international chemicals policy by focusing on a more service-oriented strategy. Mexico is one of the countries that were selected for the implementation of UNIDO's demonstration project to promote Chemical Leasing models in the country. The target sector of this project is the chemical industry, which is expected to shift their traditional business concept towards a more service and value-added approach. This is being achieved through the development of company specific business models that implement the above-indicated Chemical Leasing concept with the support from the Mexican National Cleaner Production Centre (NCPC). Results and Conclusions. The implementation of Chemical Leasing in Mexico has proven to be an efficient instrument in enhancing sustainable chemical management and significantly reducing emissions in Mexico. Several companies from the chemical industrial sector implement or agreed to implement chemical leasing business models. Based on the positive findings of the project, several Mexican companies started to negotiate contents of possible Chemical Leasing contracts with suitable business partners. The project further aimed at disseminating information on Chemical Leasing. It successfully attracted globally operating companies in the chemicals sector to explore possibilities to implement Chemical Leasing business models in Mexico. At the international level, the results of the UNIDO project were presented on 20TH September 2005 during a side event of the Strategic Approach to International Chemicals Management (SAICM) Preparation Conference in Vienna. Recommendations and Outlook. To facilitate the promotion and application of Chemical Leasing project at international level, UNIDO is currently developing a number of tools to standardize Chemical Leasing projects. These include, among others, Chemical leasing contract models; Chemical Leasing data base to find partners for chemical leasing; and guidelines to implement Chemical Leasing projects and work programmes.  相似文献   
158.
159.
A focus on communication can provide in-depth understanding of public participation in natural resource management. Analysis of empirical material from a participatory process using the theoretical concepts of discursive closure and discursive opening revealed that openings were achieved, but the perspectives represented in the process were also closed down. The reasons for closures are discussed in terms of structural constraints, with participants shown to have many different constraints and different reasons for making closures. The conclusion is that the type of theoretical analysis presented in this paper could be used by a facilitator in meetings as a participatory tool to investigate closures and open them up to achieve a more deliberative process.  相似文献   
160.
Knowledge and understanding about how the ecological systems of the Earth support life form the foundation for ecological literacy, which, in turn, is of critical importance for sustainability. There is widespread concern that levels of ecological literacy within many contemporary human societies are too low to enable effective decision-making about how to live sustainably. This paper presents and discusses the findings of an ecological literacy assessment of South Australian adults. The assessment tested for knowledge and understanding of ecological systems and interconnections with human society. Analyses revealed significant relationships between assessment scores and a range of value-based and behavioural characteristics. Such characteristics included the value placed on nature, time spent outdoors and in nature, involvement in nature-based activities, and perceived sources of ecological knowledge and understanding. Higher average scores were correlated with higher values accorded to involvement in outdoor activities, importance of the outdoors to enjoyment of life, importance of nature in the household, volunteer environmental activity and growing food. Higher scores were also correlated with higher education, research activities, outdoor lifestyles, place-based experiences, volunteer activities, mentors and colleagues, and books and magazines. Lower scores were achieved by those who considered media, natural disasters and environmental marketing to be major contributors to their ecological knowledge. These findings contribute to a broader study of the relationships between ecological literacy and a range of both socio-demographic and psychographic characteristics. They invite serious consideration from any society that values the participation of an informed population with the capacity to make sustainable environmental decisions.  相似文献   
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