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151.
新汶矿区循环经济发展模式浅析 总被引:2,自引:0,他引:2
对于资源趋于枯竭、生产成本渐高、生态环境恶化的矿区来讲,发展循环经济、打造资源节约型矿区是解决这些问题的有效手段。通过对新矿集团发展循环经济的理念、实践、总结和展望的分析研究,总结了新矿集团循环经济发展模式,对于煤炭企业发展循环经济提供借鉴,为全力打造资源节约型矿区提供参考。 相似文献
152.
Selecting reserves for forest biodiversity maintenance is often done by setting criteria for components of structural elements of biodiversity, such as a volume of decaying wood. We tested how the different threshold values for the components of structural elements affect the cost-effective site selection. Using Finnish National Forest Inventory information and remote sensing data, we determined a habitat quality index and economic value for each site in Satakunta region in Finland. Moreover, we defined several sets of potential conservation targets using alternative criteria for the habitat quality index developed for the Finnish case study. These figures were used in the site selection model in order to maximize the sum of habitat index of selected areas under a given budget constraint. We found that the production possibility frontier for the outputs of timber and biodiversity is only slightly concave when using the given threshold values. Thus, the optimal combination of the outputs is sensitive to the relative values of these goods. Our results suggest that an integrated approach in forest conservation could provide to environmental managers considerable cost savings compared with current management practices. Environmental managers could also reduce conservation costs by loosening the criteria for potential conservation targets. This would not lower considerably the quality of conserved forests. 相似文献
153.
Succession occurs on a large part of German salt marshes following abandonment or reduction of grazing. Its speed and effect
on the biodiversity of salt marshes has been discussed in the literature. Permanent plot studies show site-dependent differences
in successional outcome. If grazing is to be continued, there is uncertainty about the stocking rates that are optimal for
the conservation of plant diversity. We present an eight year permanent plot study with different grazing treatments on a
high salt marsh at the marsh island of Hallig Langeness, Germany, which is enclosed by a summer dike. The study site is owned
by WWF. Successional outcomes on the permanent plots depend on grazing intensity and depth of the groundwater table which
is correlated with soil salinity. Intermediate stocking rates support a mixture of halophytes and glycophytes, the relative
proportion of which depends on the depth of the groundwater table. Cattle grazing at stocking rates of 0.6 livestock units
per ha were found to be optimal for plant diversity conservation. At sites with deeper groundwater tables and no grazing,
dominantElymus spp. stands develop and diversity is strongly reduced. If the groundwater table is high, succession following grazing abandonment
is retarded and small halophytes prevail. 相似文献
154.
M. R. Phillips E. J. Abraham A. T. Williams C. House 《Journal of Coastal Conservation》2007,11(3):159-170
Fifteen beaches from the Swansea Bay coastal sediment cell, South Wales, UK, were analysed via function analysis, involving
assessment of specific environmental and socio-economic indicators. These were allocated scores from field surveys and extensive
desktop studies, which included beach awards, relevant shoreline management plans, planning and conservation designations
and current legislation. Normalised scores allowed production of a conservation/development matrix, enabling beach location
in conservation, development or conflict fields, which results appropriately identified. Conservation field beaches tended
to have a low density residential hinterland with little or no commercialisation. Conversely, beaches that leant towards the
development field had a high density residential hinterland and were highly commercialised. Evaluation showed the importance
of planning legislation in conflict areas and identified locations of development potential, where significant environmental
consequences would be unlikely. This representation could be used for evolution of conservation/development status within
coastal areas, enabling policy adjustment as necessary. It will also enable future sustainability assessment and it is suggested
that indicators could be modified to reduce environmental emphasis and provide a more uniform socio-economic consideration. 相似文献
155.
Coral reefs are highly dynamic and productive marine ecosystems, providing habitat and refuge for an enormous number of species
including fish, invertebrates and algae. With increased anthropogenic pressures and global climate change, many coral reefs
are rapidly declining. Currently, there is limited knowledge on condition and community assemblage composition of shallow
fringing coral reefs along the south-eastern coast of Queensland, Australia. With increased demand to determine existence
of coastal fringing reefs by National Regional Management groups, a rapid cost effective method to determine reef composition
and condition was required. The aim of this study was to determine the benthic structure and extent of two small coastal fringing
reefs (Hummock Hill Reef and Stringers Reef) along the Southern Great Barrier Reef. Reef substrate assessments were carried
out using a rapid assessment technique and a Point Intercept Method (PIM). The data were analysed and classified using a Geographic
Information System (GIS). Percent substrate cover was calculated using a visual basic image analysis program. The Point intercept
method showed higher accuracy over the rapid assessment technique (up to 15–40% difference) and was thus deemed a more suitable
classification tool for reefs with high structural complexity and heterogeneity. This study focused on piloting a rapid, cost
effective Point Intercept Technique using random point count methodology to document coral benthic habitat and extent over
a commonly used rapid assessment method as a tool for reef coastal management and conservation. The two techniques were compared
and substrate classification success, limitations and errors were discussed. 相似文献
156.
Soil microarthropods (Acari, Collembola) were analyzed along transects from shore to brown dune in two sandy coastal sites
of the North Sea (Jutland, Denmark, and Spiekeroog, East Frisian island, Germany). Predatory mites (Acari: Gamasina) and Collembola
were determined to species. The Jutland and the Spiekeroog sites each yielded 22 Gamasina species, 10 of which are common
to both areas. Collembola were identified from the Spiekeroog samples only (also 22 species).
Largest mite abundances were found in Jutland in primary dunes (419 tsd. ind./m2) and on Spiekeroog in old brown dunes (314 tsd.ind./m2). Compared to the mites, Collembola abundances are low, with maxima of 77 tsd.ind./m2 in Jutland (yellow dune) and only 18 tsd. ind./m2 on Spiekeroog (old vellow dune).
The communities of predatory mites (Gamasina) and Collembola along transects from shore inland to brown dune are quite specific.
High similarities are found for the predatory mites between the specific dune sites of the two North Sea areas, particularly
for yellow dune.
Additionally, preliminary data are presented for the southern Baltic Coast. The findigns are discussed in a broader context.
Arguments focus on conservation and biogenic dune stabilization. 相似文献
157.
Assessing the effectiveness of specially protected areas for conservation of Antarctica's botanical diversity
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Vegetation is sparsely distributed over Antarctica's ice‐free ground, and distinct plant communities are present in each of the continent's 15 recently identified Antarctic Conservation Biogeographic Regions (ACBRs). With rapidly increasing human activity in Antarctica, terrestrial plant communities are at risk of damage or destruction by trampling, overland transport, and infrastructure construction and from the impacts of anthropogenically introduced species, as well as uncontrollable pressures such as fur seal (Arctocephalus gazella) activity and climate change. Under the Protocol on Environmental Protection to the Antarctic Treaty, the conservation of plant communities can be enacted and facilitated through the designation of Antarctic Specially Protected Areas (ASPAs). We examined the distribution within the 15 ACBRs of the 33 ASPAs whose explicit purpose includes protecting macroscopic terrestrial flora. We completed the first survey using normalized difference vegetation index (NDVI) satellite remote sensing to provide baseline data on the extent of vegetation cover in all ASPAs designated for plant protection in Antarctica. Large omissions in the protection of Antarctic botanical diversity were found. There was no protection of plant communities in 6 ACBRs, and in another 6, <0.4% of the ACBR area was included in an ASPA that protected vegetation. Protected vegetation cover within the 33 ASPAs totaled 16.1 km2 for the entire Antarctic continent; over half was within a single protected area. Over 96% of the protected vegetation was contained in 2 ACBRs, which together contributed only 7.8% of the continent's ice‐free ground. We conclude that Antarctic botanical diversity is clearly inadequately protected and call for systematic designation of ASPAs protecting plant communities by the Antarctic Treaty Consultative Parties, the members of the governing body of the continent. 相似文献
158.
A Standard Lexicon for Biodiversity Conservation: Unified Classifications of Threats and Actions 总被引:3,自引:0,他引:3
NICK SALAFSKY††† DANIEL SALZER† ALISON J. STATTERSFIELD‡ CRAIG HILTON-TAYLOR§ RACHEL NEUGARTEN† STUART H. M. BUTCHART‡ BEN COLLEN NEIL COX†† LAWRENCE L. MASTER‡‡ SHEILA O'CONNOR§§ DAVID WILKIE 《Conservation biology》2008,22(4):897-911
Abstract: An essential foundation of any science is a standard lexicon. Any given conservation project can be described in terms of the biodiversity targets, direct threats, contributing factors at the project site, and the conservation actions that the project team is employing to change the situation. These common elements can be linked in a causal chain, which represents a theory of change about how the conservation actions are intended to bring about desired project outcomes. If project teams want to describe and share their work and learn from one another, they need a standard and precise lexicon to specifically describe each node along this chain. To date, there have been several independent efforts to develop standard classifications for the direct threats that affect biodiversity and the conservation actions required to counteract these threats. Recognizing that it is far more effective to have only one accepted global scheme, we merged these separate efforts into unified classifications of threats and actions, which we present here. Each classification is a hierarchical listing of terms and associated definitions. The classifications are comprehensive and exclusive at the upper levels of the hierarchy, expandable at the lower levels, and simple, consistent, and scalable at all levels. We tested these classifications by applying them post hoc to 1191 threatened bird species and 737 conservation projects. Almost all threats and actions could be assigned to the new classification systems, save for some cases lacking detailed information. Furthermore, the new classification systems provided an improved way of analyzing and comparing information across projects when compared with earlier systems. We believe that widespread adoption of these classifications will help practitioners more systematically identify threats and appropriate actions, managers to more efficiently set priorities and allocate resources, and most important, facilitate cross‐project learning and the development of a systematic science of conservation. 相似文献
159.
The present research examines whether collective guilt for an ingroup's collective greenhouse gas emissions mediates the effects of beliefs about the causes and effects of global warming on willingness to engage in mitigation behavior. In Study 1, we manipulate the causes and effects of global warming and then measure collective guilt. Results demonstrate that collective guilt for Americans' greenhouse gas emissions is stronger when participants believe that global warming is caused by humans and will have minor effects. Study 2 employs the same manipulations and then measures collective guilt and collective anxiety, as well as willingness to conserve energy and pay green taxes. This study replicates the effect from Study 1 and rules out collective anxiety as a plausible alternative mediator. Collective guilt for Americans' greenhouse emissions was the only reliable mediator of the effect of beliefs about global warming on willingness to engage in mitigation behaviors. The importance of collective guilt as a tool for promoting global warming mitigation is discussed. 相似文献
160.
The Strategic Plan for Biodiversity 2011–2020 recognizes the increasing importance of scientific knowledge to support conservation policies and decision making. In this study, we assessed the tendency of such knowledge in the first decade of the 21st century. We carried out a systematic review of publications in biodiversity conservation, considering the following aspects: type of research, main topic of study, object of study (i.e. biodiversity organizational level, taxonomic groups and ecosystems), pressures and drivers of change, as well as geographical distribution. In total, 966 publications were analyzed within the three journals with higher academic reach in the field under study: Biodiversity & Conservation, Biological Conservation, and Conservation Biology. Our results show that there are several biases in scientific knowledge associated with the object of study, and analyzed drivers of changes, as well as geographical distribution. However, research trends are not uniform along the first decade of 21st century, as there are some differences between 2000 and 2011 regarding the main topic of the study, the spatial scale and geographical region, and the analyzed ecosystems. We finally discuss the implications of current knowledge trends in biodiversity conservation for achieving the targets delineated by the Strategic Plan for Biodiversity 2011–2020. 相似文献