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173.
东北自然保护区压力威胁影响因子及趋势 总被引:4,自引:0,他引:4
论文运用世界自然保护区委员会(WCPA)和世界自然基金会(WWF)推荐的自然保护区管理快速评估和优先性确定方法(RAPPAM),对东北地区部分自然保护区面临的压力和威胁及其发展趋势进行了调查分析。结果显示,在保护区所面临的14种威胁因子中,火灾、林木砍伐、偷猎、非林木产品采集(NTFP)、旅游、放牧6个因子的影响范围较广、影响程度较高、影响时间较长,是保护区应重点控制的威胁因子。因此,今后的保护区管理应加强对火灾、林木砍伐和非木质林产品采集等因素的监控,同时通过制定相关政策、采取适当措施有效控制并减少保护区生态旅游对保护对象产生的负面影响,提高保护区管理的有效性。 相似文献
174.
Testing the limits of social resilience in ant colonies 总被引:4,自引:0,他引:4
Sarah J. Backen A. B. Sendova-Franks Nigel R. Franks 《Behavioral ecology and sociobiology》2000,48(2):125-131
Social resilience is the ability of Leptothorax ant colonies to re-assemble after dissociation, as caused, for example, by an emigration to a new nest site. Through social
resilience individual workers re-adopt their spatial positions relative to one another and resume their tasks without any
time being wasted in worker respecialisation. Social resilience can explain how an efficient division of labour can be maintained
throughout the trials and tribulations of colony ontogeny including the, often substantial, period after the queen dies when
the ability to conserve worker social relationships may be essential for efficiency to be maintained. The mechanism underlying
social resilience is, therefore, expected to be robust even in the absence of many of the colony’s components, such as the
queen, the brood and even a large proportion of the workers. Such losses are likely, given the ecology of this genus. Using
sociotomy experiments, we found that social resilience can occur in the absence of the queen. Furthermore, the spatial component
of social resilience can occur even when the queen, the brood, as well as a large proportion of the workers, are all absent
simultaneously and hence many of the tasks are missing. We conclude, therefore, that social resilience is indeed robust. This
does not, however, preclude worker flexibility in response to changes in task supply and demand. We propose a possible sorting
mechanism based on worker mobility levels which might explain the robustness underlying this phenomenon.
Received: 25 October 1999 / Accepted: 1 April 2000 相似文献
175.
The use of an Integrated Landscape Ecological Approach on the evaluation of the impact of a proposed highway over a high sensitive habitat of the highly endangered Iberian Lynx (Lynx pardina L) is described. This method prevents the occurrence of common errors in the decision making process by allowing an increased knowledge of the ecological constraints of the project. It builds, consequently, a very powerful tool for nature conservation assessment and for the ecological evaluation and the decision process in situations of low ecological data availability. The conflict of arguments on the consistency of the conclusions of the method is also described. 相似文献
176.
We developed an approach for inventorying wetland resources, assessing their condition, and determining restoration potential
in a watershed context. This article outlines how this approach can be developed into a Wetland Monitoring Matrix (WMM) that
can help resource management agencies make regulatory and nonregulatory decisions. The WMM can be embedded in a standard planning
process (Wetlands, Wildlife, and Watershed Assessment Techniques for Evaluation and Restoration, or W3ATER) involving the setting of objectives, assessing the condition of the resource, prioritizing watersheds or sites, implementing
projects, and evaluating progress. To that process we have added the concepts of reference, hydrogeomorphic (HGM) classification,
and prioritization for protection and restoration by triage or adaptive management. Three levels of effort are possible, increasing
in detail and diagnostic reliability as data collection shifts from remote sensing to intensive sampling on the ground. Of
key importance is the use of a consistent set of monitoring protocols for conducting condition assessments, designing restoration
and creation projects, and evaluating the performance of mitigation projects; the same variables are measured regardless of
the intended use of the data. This approach can be tailored to any region by establishing a reference set of wetlands organized
by HGM subclasses, prioritizing watersheds and individual wetlands, and implementing consistent monitoring protocols. Application
of the approach is illustrated with examples from wetlands and streams of the Spring Creek Watershed in central Pennsylvania,
USA. 相似文献
177.
Cornelis A.M. van Gestel Josée E. Koolhaas Maarten van Hoppe Cora Korsman 《Environmental pollution (Barking, Essex : 1987)》2009,157(3):895-903
Effects on earthworms in the contaminated floodplain area the Biesbosch, the Netherlands, were determined at different levels of organization using a combination of field and laboratory tests. The species Lumbricus rubellus, collected from different polluted sites in the Biesbosch, showed reduced values for the biomarker neutral red retention time (NRRT), mainly explained by high metal concentrations in the soil and the resulting high internal copper concentrations in the earthworms. Organic pollutant levels in earthworms were low and did not explain reduced NRRTs. Earthworm abundance and biomass were not correlated with pollutant levels in the soil. Litterbag decomposition and bait-lamina feeding activity, measures of the functional role of earthworms, were not affected by metal pollution and did not show any correlation with metal concentrations in soil or earthworms nor with NRRT. Effects at the biochemical level therefore did not result in a reduced functioning of earthworm communities. 相似文献
178.
岩溶地区作为一个特殊的地理环境单元,具有环境承载量低、地表崎岖破碎、植被生长困难、生态环境脆弱的特点。该文以岩溶地貌发育典型、碳酸盐岩出露面积广的贵州省为例,论述了岩溶区生态环境脆弱性类型划分的主要原则,探讨了脆弱性类型划分的指标并进行了量化。在此基础上,用灰色关联度分析确定了各影响因子(指标)的权重,经过综合评判,笔者把贵州岩溶区生态环境脆弱性类型划分为5类:剧烈脆弱区、强度脆弱区、中度脆弱区、轻度脆弱区和潜在脆弱区,并针对各脆弱性类型区的特点,提出了相应的防治对策。 相似文献
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180.
The pollution caused by agricultural production poses a threat to the ecological integrity of river ecosystems, altering the structure and function of river ecosystems. Differences in microbial community structure provide useful information about the impact of agricultural pollution on the biological integrity of ecosystems, but generally convey little information regarding ecosystem functions. In this study, using Illumina MiSeq sequencing technology based on the 16S rRNA gene, river sediment samples associated with four different types of agricultural pollution were comprehensively analyzed. The results show that the total organic carbon (TOC) content was highest at the YZS site (animal husbandry sewage) among the assayed sites, but the species richness and uniformity were lowest at this site, which may have been caused by the high nutrient source of the sewage. Furthermore, in the three YZS samples affected by the long-term discharge of aquaculture tail-water, the unique genus Dechloromonas and the genus Candidatus-Competitor were observed, which are strongly correlated with phosphorus conversion. The formation of network modules may correspond to the coexistence of functional bacteria accustomed to multiple niche combinations under different agricultural pollution conditions in river sediments. According to the PICRUSt functional prediction, the bacterial community in the agricultural polluted river sediment primarily harbored 46 subfunctions, exhibiting richness of functions. Overall, our results provide a more comprehensive understanding of the structure and ecological processes associated with the aggregation of bacterial communities, which is beneficial for the management of river environments. 相似文献