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421.
Indentifying common priorities in shared natural resource systems constitutes an important platform for implementing adaptation and a major step in sharing a common responsibility in addressing climate change. Predominated by discourses on REDD + (Reduced Emissions from Deforestation and Forest Degradation and conservation, sustainable management of forests and enhancement of forest carbon stocks in developing countries) with little emphasis on adaptation there is a risk of lack of policy measures in addressing climate change in the Congo Basin. Forest products and ecosystem services provide security portfolios for the predominantly rural communities, and play major roles in national development programmes in both revenue and employment opportunities. Thus, raising the profile of forests in the policy arena especially in the twin roles of addressing climate change in mitigation and adaptation and achieving resilient development is crucial. Within the framework of the Congo Basin Forests and Climate Change Adaptation project (COFCCA) project, science policy dialogue was conducted to identify and prioritize forest based sectors vulnerable to climate change but important to household livelihoods and national development. The goal of the prioritization process was for the development of intervention in forest as measures for climate change adaptation in Central Africa. Participants constituted a wide range of stakeholders (government, Non Governmental Organizations, research institutions, universities, community leaders, private sectors etc.) as representatives from three countries directly involved in the project: Cameroon, Central African Republic and Democratic Republic of Congo. Building on national priorities, four forest related sectors were identified as common priorities at the regional level for focus on climate change adaptation. These sectors included: (1) energy with emphasis on fuel wood and Charcoal; (2) Water principally quality, quantity, accessibility, etc.; (3) Food with emphasis on Non Timber Forest Products, and (4) Health linked to healthcare products (medicinal plants). Using these prioritized sectors, the project focused on addressing the impacts of climate change on local communities and the development of adaptation strategies in the three pilot countries of the Congo Basin region. The four sectors constitute the key for development in the region and equally considered as priority sectors in the poverty reduction papers. Focused research on these sectors can help to inject the role of forests in national and local development and their potentials contributions to climate change adaptation in national and public discourses. Mainstreaming forest for climate change adaptation into national development planning is the key to improve policy coherence and effectiveness in forest management in the region.  相似文献   
422.
浅谈环境应急监测质量管理体系的建设   总被引:1,自引:0,他引:1  
环境应急监测作为环境应急处置的基础环节,发挥着重要的决策支持和技术保障作用。本文主要论述了各级环境监测部门如何从组织体系、网络体系、信息体系、质量控制体系和评估及预测体系5个方面建立一套完善的环境应急监测质量管理体系,以确保环境应急监测的质量,为环境管理提供可靠的技术支持。  相似文献   
423.
京杭大运河苏州高新区段水质污染状况研究   总被引:3,自引:0,他引:3  
以2005—2010年京杭大运河苏州高新区段水质监测数据为基础,运用内梅罗综合污染指数法以及采取方差分析对京杭大运河苏州高新区段水质的主要污染因子及其变化趋势进行了研究,并对京杭大运河水质污染状况进行了综合评价。结果表明:京杭大运河苏州高新区段主要污染物为氨氮、总磷;氨氮浓度在2006—2010年间虽有明显下降,但仍超过《地表水环境质量标准》(GB3838—2002)IV类水质要求,为劣V类水,总磷亦有明显下降,但在2008—2010年3年间其浓度略有波动,在IV类和V类水质之间浮动;2005—2008年间其水质处于污染状态,2009—2010年水质较好,为轻污染。该研究结果可为苏州高新区河流水环境治理提供科学依据。  相似文献   
424.
动火作业中的安全现状分析   总被引:3,自引:0,他引:3  
常武  邢晶 《安全》2007,28(11):25-28
结合新疆八一钢铁集团实际,对动火作业现状进行分析,提出不足;并结合法规、标准要求以及工作实践,从管理、技术、培训等方面提出动火安全的几点对策.  相似文献   
425.
Myrmecophily provides various examples of how social structures can be overcome to exploit vast and well-protected resources. Ant nest beetles (Paussinae) are particularly well suited for ecological and evolutionary considerations in the context of association with ants because life habits within the subfamily range from free-living and predatory in basal taxa to obligatory myrmecophily in derived Paussini. Adult Paussini are accepted in the ant society, although parasitising the colony by preying on ant brood. Host species mainly belong to the ant families Myrmicinae and Formicinae, but at least several paussine genera are not host-specific. Morphological adaptations, such as special glands and associated tufts of hair (trichomes), characterise Paussini as typical myrmecophiles and lead to two different strategical types of body shape: while certain Paussini rely on the protective type with less exposed extremities, other genera access ant colonies using glandular secretions and trichomes (symphile type). We compare these adaptations with other taxonomic groups of insects by joining contemporary research and early sources and discuss the possibility of an attracting or appeasing effect of the secretion. Species that are ignored by their host ants might use chemical mimicry instead. Furthermore, vibrational signals may contribute to ant–beetle communication, and chemical signals have proven to play a role in host finding. The powerful defense chemistry of paussines as “bombardier beetles” is not used in contact with host ants. We attempt to trace the evolution of myrmecophily in paussines by reviewing important aspects of the association between paussine beetles and ants, i.e. morphological and potential chemical adaptations, life cycle, host specificity, alimentation, parasitism and sound production.
Stefanie F. GeiselhardtEmail:
  相似文献   
426.
(E)-6,10-dimethyl-5,9-undecadien-2-ol (geranyl acetol), termed here fuscol, was identified as a male-produced pheromone emitted by Tetropium fuscum (F.) and Tetropium cinnamopterum Kirby. In field experiments, traps baited with synthetic fuscol alone were not significantly attractive, but the combination of fuscol plus host volatiles (a synthetic blend of monoterpenes plus ethanol) attracted significantly more male and female T. fuscum and female T. cinnamopterum than did host volatiles alone. This is the first homoterpenoid alcohol to be described in the Cerambycidae, and the first pheromone reported from the sub-family Spondylidinae.  相似文献   
427.
Dispersers are expected to assess breeding habitat quality before settlement. Although cues reflecting habitat quality are well studied, social cues have not been as well evaluated. In this paper, we studied breeding habitat selection during 3 years in a natural population of blue tits, Cyanistes caeruleus, breeding in nest-boxes. Our aim was to investigate if this species used conspecific density and/or reproductive success of con- and heterospecifics (i.e., social cues) in settlement decisions. The patterns observed were consistent with the idea that juveniles, when dispersing from their natal patches, did not react to any of the cues that we tested. In contrast, breeders that dispersed seemed to respond to both conspecific mean patch reproductive success (PRS) and breeding density of the settlement patch in the year of dispersal, their response differing according to their own reproductive success. Indeed, failed breeders moved to areas with high PRS and low density relative to source patches, while successful breeders behaved the opposite. The comparison between juveniles and adults might be modulated by the limited time available to juveniles to gather information on PRS and density at the end of the dispersing year. Adults lacking these time constraints, however, seemed to rely on these conspecific cues although limited by their own quality. Additionally, breeders were more likely to be immigrants in patches with relatively low breeding success and density the previous year, suggesting that settlement is influenced by multiple cues, which may reveal information on different aspects of habitat and be available at different moments. Collectively, our results support the importance of social cues for blue tits’ settlement.  相似文献   
428.
Although Asia is thought to have played a critical role in the radiation of artiodactyls, the fossil record of stem selenodonts (“dichobunoids”) remains dramatically poor in tropical Asian regions. In this study, we report a new dichobunid genus and species Cadutherium kyaukmagyii and a new basal ruminant genus and species Irrawadymeryx pondaungi, from the late Middle Eocene Pondaung Formation, Central Myanmar. Although the scarcity of the present material prevents any attempts to investigate the phylogenetic relationships of Cadutherium with contemporaneous forms from other Holarctic landmasses, this new form shed new light on the diversity of these small rabbit-like ungulates during a key period of their evolutionary history. Reexamination of the small-bodied artiodactyls from Pondaung leads us to propose new identifications of certain published specimens and, in turn, to investigate the temporal and geographic distribution of taxa recognized in the Pondaung Formation. Although fragmentary, these potential new taxa reveal an unsuspected diversity of small forms among artiodactyls of Pondaung. This addition to the Eocene record of dichobunoids and early ruminants provides further insight in the diversity of dental patterns among small artiodactyls from the Pondaung Formation and attests to the antiquity of these groups in Southeast Asia.  相似文献   
429.
Power matters in closing the phenotyping gap   总被引:1,自引:0,他引:1  
Much of our understanding of physiology and metabolism is derived from investigating mouse mutants and transgenic mice, and open-access platforms for standardized mouse phenotyping such as the German Mouse Clinic (GMC) are currently viewed as one powerful tool for identifying novel gene-function relationships. Phenotyping or phenotypic screening involves the comparison of wild-type control mice with their mutant or transgenic littermates. In our study, we explored the extent to which standardized phenotyping will succeed in detecting biologically relevant phenotypic differences in mice generated and provided by different collaborators. We analyzed quantitative metabolic data (body mass, energy intake, and energy metabolized) collected at the GMC under the current workflow, and used them for statistical power considerations. Our results demonstrate that there is substantial variability in these parameters among lines of wild-type C57BL/6 (B6) mice from different sources. Given this variable background noise in mice that serve as controls, subtle phenotypes in mutant or transgenic littermates may be overlooked. Furthermore, a phenotype observed in one cohort of a mutant line may not be reproducible (to the same extent) in mice coming from a different environment or supplier. In the light of these constraints, we encourage researchers to incorporate information on intrastrain variability into future study planning, or to perform advanced hierarchical analyses. Both will ultimately improve the detectability of novel phenotypes by phenotypic screening. Carola W. Meyer and Ralf Elvert contributed equally to this work.  相似文献   
430.
The morphological characteristics of sperm and reproductive organs may offer clues as to how reproductive systems have evolved. In this paper, the morphologies of the sperm and male reproductive organs of carabid beetles in the tribe Pterostichini (Coleoptera: Carabidae) are described, and the morphological associations among characters are examined. All species form sperm bundles in which the head of the sperm was embedded in a rod-shaped structure, i.e., spermatodesm. The spermatodesm shape (left-handed spiral, right-handed spiral, or without conspicuous spiral structure) and the condition of the sperm on the spermatodesm surface (with the tail free-moving or forming a thin, sheetlike structure) vary among species. In all species, the spiral directions of the convoluted seminal vesicles and vasa deferentia are the same on both sides of the body; that is, they show an asymmetric structure. The species in which the sperm bundle and the seminal vesicles both have a spiral structure could be classified into two types, with significant differences in sperm-bundle length between the two types. The species with a sperm-bundle spiral and seminal-vesicle spiral of almost the same diameter have longer sperm bundles than the species with a sperm-bundle spiral and seminal-vesicle tube of almost the same diameter. In the former type, the spiral directions of the sperm bundles and seminal vesicles are inevitably the same, whereas they differ in some species with the later type. Therefore, increased sperm bundle length appears to have been facilitated by the concordance of the sperm bundle’s coiling direction with the coiling direction of the seminal vesicle.  相似文献   
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