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141.
Neil Glasson 《Journal of Environmental Planning and Management》1987,30(2):84-90
This paper looks at the use and effectiveness of the Site of Special Scientific Interest designation in three counties in the East Midlands region of the Nature Conservancy Council, namely Nottinghamshire, Northamptonshire and Cambridgeshire. Using unpublished sources within the NCC an analysis is made of the SSSI system in practice since its inception in 1949. A number of findings relating to weaknesses in the designation and the operation of the designation system emerge. Each of these findings is discussed in turn with the presentation of the appropriate evidence from the county case studies. 相似文献
142.
Marine reserves have become widely used in biodiversity conservation and are increasingly proposed as fisheries management tools. Previous modeling studies have found that reserves may increase or decrease yields, depending on local environmental conditions and on the specific life-history traits of the fishery species. Sex-changing (female-to-male) fish are targets of some of the most important commercial and recreational fisheries in the world. The potential for disproportionate removal of the larger, older sex of such species requires new theory to facilitate our understanding of how reserves will affect the yields of surrounding fisheries, relative to fishes with separate sexes. We investigated this question by modeling the effects of marine reserves on a non-sex-changing and a sex-changing population. We used demographic parameter estimates for the common coral trout as a baseline, and we conducted extensive sensitivity analyses to determine how sustainable yields of sex-changing species are likely to be affected by reserves across a broad range of life-history parameters. Our findings indicate that fisheries for sex-changing species are unlikely to receive the same yield-enhancing benefit that non-sex-changing fisheries enjoy from marine reserves, and that often reserves tend to reduce sustainable yields for a given overall population size. Specifically, the increased egg production and high fertilization success within reserves is more than offset by the reduced egg production and fertilization success in the fished areas, relative to a system in which fishing mortality is distributed more evenly over the entire system. A key reason for this appears to be that fertilization success is reduced, on average, when males are unevenly distributed among subpopulations, as is the case when reserves are present. These findings suggests that, for sex-changing populations, reserves are more suited to rebuilding overfished populations and sustaining fishery viability, rather than enhancing fishery yields. These results are robust over a range of sex-change regimes, stock-recruitment relationships, adult mortality rates, individual growth strategies, and fertilization-success functions. Our findings highlight the importance of considering the different contributions of males and females to population growth and fishery yields when evaluating the efficacy of marine reserves for enhancement of fished species. 相似文献
143.
Elizabeth J. Green Graeme M. Buchanan Stuart H. M. Butchart Georgina M. Chandler Neil D. Burgess Samantha L. L. Hill Richard D. Gregory 《Conservation biology》2019,33(6):1360-1369
To inform governmental discussions on the nature of a revised Strategic Plan for Biodiversity of the Convention on Biological Diversity (CBD), we reviewed the relevant literature and assessed the framing of the 20 Aichi Biodiversity Targets in the current strategic plan. We asked international experts from nongovernmental organizations, academia, government agencies, international organizations, research institutes, and the CBD to score the Aichi Targets and their constituent elements against a set of specific, measurable, ambitious, realistic, unambiguous, scalable, and comprehensive criteria (SMART based, excluding time bound because all targets are bound to 2015 or 2020). We then investigated the relationship between these expert scores and reported progress toward the target elements by using the findings from 2 global progress assessments (Global Biodiversity Outlook and the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services). We analyzed the data with ordinal logistic regressions. We found significant positive relationships (p < 0.05) between progress and the extent to which the target elements were perceived to be measurable, realistic, unambiguous, and scalable. There was some evidence of a relationship between progress and specificity of the target elements, but no relationship between progress and ambition. We are the first to show associations between progress and the extent to which the Aichi Targets meet certain SMART criteria. As negotiations around the post-2020 biodiversity framework proceed, decision makers should strive to ensure that new or revised targets are effectively structured and clearly worded to allow the translation of targets into actionable policies that can be successfully implemented nationally, regionally, and globally. 相似文献
144.
145.
Neil S. Grigg 《Journal of the American Water Resources Association》1999,35(3):527-534
ABSTRACT: Improving water management to meet future global needs will certainly require technical advances, but the main challenge is to integrate the viewpoints of diverse societal interests into decisions about allocation of water resources. The integration cannot be done solely by the market because it requires a balancing among interests which do not respond well to market forces, nor by the state alone because of institutional problems. The concept of “integrated water resources management” has been developed to provide the framework for the required balancing of interests, and, like similar concepts in industries other than water, it has a dual purpose - to link stakeholders and apply best practices to management actions. To clarify the process of integrated water management, the paper focuses on two questions: who should lead integrated water resources management and who should pay for it? Several examples are given to illustrate a range of situations. The paper concludes with a call to improve paradigms of integrated water management, a proposition that water organizations should accept and budget for their external responsibilities as well as their direct missions, affirmation of the need for state and federal agencies to be involved with local interests, a call for better scientific and public information, and identification of the need for continued work to improve the process of integrated water management. 相似文献
146.
Neil Aldrin D. Mallari Nigel J. Collar Philip J. K. McGowan Stuart J. Marsden 《Ambio》2016,45(3):313-322
Aichi Target 11 of the Convention on Biological Diversity urges, inter alia, that nations protect at least 17 % of their land, and that protection is effective and targets areas of importance for biodiversity. Five years before reporting on Aichi targets is due, we assessed the Philippines’ current protected area system for biodiversity coverage, appropriateness of management regimes and capacity to deliver protection. Although protected estate already covers 11 % of the Philippines’ land area, 64 % of its key biodiversity areas (KBAs) remain unprotected. Few protected areas have appropriate management and governance infrastructures, funding streams, management plans and capacity, and a serious mismatch exists between protected area land zonation regimes and conservation needs of key species. For the Philippines to meet the biodiversity coverage and management effectiveness elements of Aichi Target 11, protected area and KBA boundaries should be aligned, management systems reformed to pursue biodiversity-led targets and effective management capacity created. 相似文献
147.
Neil H. Carter José Vicente López-Bao Jeremy T. Bruskotter Meredith Gore Guillaume Chapron Arlyne Johnson Yaffa Epstein Mahendra Shrestha Jens Frank Omar Ohrens Adrian Treves 《Ambio》2017,46(3):251-264
The growing complexity and global nature of wildlife poaching threaten the survival of many species worldwide and are outpacing conservation efforts. Here, we reviewed proximal and distal factors, both social and ecological, driving illegal killing or poaching of large carnivores at sites where it can potentially occur. Through this review, we developed a conceptual social–ecological system framework that ties together many of the factors influencing large carnivore poaching. Unlike most conservation action models, an important attribute of our framework is the integration of multiple factors related to both human motivations and animal vulnerability into feedbacks. We apply our framework to two case studies, tigers in Laos and wolverines in northern Sweden, to demonstrate its utility in disentangling some of the complex features of carnivore poaching that may have hindered effective responses to the current poaching crisis. Our framework offers a common platform to help guide future research on wildlife poaching feedbacks, which has hitherto been lacking, in order to effectively inform policy making and enforcement. 相似文献
148.
Harris KA Yunker MB Dangerfield N Ross PS 《Environmental pollution (Barking, Essex : 1987)》2011,159(10):2665-2674
Sediment-associated hydrocarbons can pose a risk to wildlife that rely on benthic marine food webs. We measured hydrocarbons in sediments from the habitat of protected sea otters in coastal British Columbia, Canada. Alkane concentrations were dominated by higher odd-chain n-alkanes at all sites, indicating terrestrial plant inputs. While remote sites were dominated by petrogenic polycyclic aromatic hydrocarbons (PAHs), small harbour sites within sea otter habitat and sites from an urban reference area reflected weathered petroleum and biomass and fossil fuel combustion. The partitioning of hydrocarbons between sediments and adjacent food webs provides an important exposure route for sea otters, as they consume ∼25% of their body weight per day in benthic invertebrates. Thus, exceedences of PAH sediment quality guidelines designed to protect aquatic biota at 20% of the sites in sea otter habitat suggest that sea otters are vulnerable to hydrocarbon contamination even in the absence of catastrophic oil spills. 相似文献
149.
Monitoring of heavy metal levels in roadside dusts of Thessaloniki, Greece in relation to motor vehicle traffic density and flow 总被引:5,自引:0,他引:5
In recent years, the level of heavy metal pollution in urban areas has been of considerable concern. The principal source has been attributed to the motor vehicle and increasing inner city congestion, which has lead to a change and enlargement of transport stop-start zones. These areas of high traffic density are associated with an increased release of heavy metals into the adjacent residential or commercial areas. Seventy-five roadside dust samples were collected throughout the inner city and by-pass motorway areas of Thessaloniki, Northern Greece. Samples were taken from arterial, major and minor roads, as well as the ring road, to compare and contrast the levels of heavy metals, namely Cu, Zn, Cd, Mn and Pb. Flame Atomic Absorption Spectroscopy (FAAS) was developed to quantitatively determine concentrations of both total element and geochemical fractionation, within the two dust particulate fraction sizes <75 microm and 75-125 microm. Acid digestion using Aqua Regia (3:1 conc. HCl:HNO(3)) was employed for the total elemental analysis, a method that was validated through the use of certified reference materials (CRM). Fractionation studies involved a three-step sequential extraction method performed on five selected samples (representatives of high, mid and low total elemental concentrations). The resultant solutions were analysed for lead and zinc levels to ascertain fractionation throughout the different geochemical fractions, thus assessing bioavailability.It was found that congestion/stop-start traffic patterns did influence and have led to increased levels of heavy metal deposition along inner city roads compared to levels observed on the new relief ring road. Dust particulate fraction sizes were only found to show statistically significant differences in cadmium and manganese, at the probability P < 0.001 or 99.9% confidence limit. Both Cd and Mn showed higher total levels in the smaller fraction sizes (<75 microm), implying that their major release source is exhaust emissions. There were no significant differences in the other elements, at the P > 0.05 or 95% confidence limit. Road type was seen to have little affect on cadmium and manganese, though lead, copper and zinc were all found to show higher levels on the inner city routes. This can be related back to the wear-and-tear of vehicle components as a result of the stop-start traffic patterns (brake pads etc). Both Pb and Zn have shown to be in chemical forms that are bio available to ecosystems. 相似文献
150.