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261.
Castello L Viana JP Watkins G Pinedo-Vasquez M Luzadis VA 《Environmental management》2009,43(2):197-209
Fishers and small-scale fisheries worldwide have been marginalized historically. Now it is clear that integrating fishers
in management processes is key to resource conservation, but it is less clear how to do it. Here, based on a literature review and new information, we present and analyze a case in which the participation
of fishers in the management process was crucial in recovering an overexploited small-scale fishery for the pirarucu (Arapaima spp.) in the Amazon Basin, Brazil. In 8 years of experimental management, from 1999 to 2006, the population of pirarucu increased
9-fold (from about 2200 to 20,650 individuals), harvest quotas increased 10-fold (from 120 to 1249 individuals), and fishers’
participation in the management process increased and they benefited from increased monetary returns. Additionally, the number
of communities conducting the management scheme increased from 4 in 1999 to 108 in 2006, following the demands of fishers
and regional government agencies. Based on our analysis, we suggest that the participation of fishers in the management of
other small-scale fisheries in the world can be improved by focusing on (1) applying the knowledge and skills of fishers in
resource monitoring and management, (2) bridging knowledge systems among all involved stakeholders, (3) collaborating with
fishers that are interested in, and capable of conducting, resource conservation schemes, and (4) conducting management under
conditions of uncertainty. 相似文献
262.
Hydrogeomorphic (HGM) functional assessment models were used to assess whether function in created wetlands of two ages (1 year
old and >12 years old) was equivalent to that of natural (reference) mainstem floodplain wetlands. Reference wetlands scored
higher than both created age classes for providing energy dissipation and short-term surface water storage. Reference wetlands scored higher in maintaining native plant community and structure than 1-year-old sites, and 12-year-old wetlands scored higher than reference sites for providing vertebrate habitat structure. Analysis of individual model variables showed that reference wetlands had greater vegetative biomass and higher soil organic
matter content than both created wetland age classes. Created wetlands were farther from natural wetlands and had smaller
mean forest patch sizes within a 1-km-radius circle around the site than did the reference sites, indicating less hydrologic
connectivity. Created wetlands also had less microtopographic variation than reference wetlands. The 1-year-old created sites
were placed in landscape settings with greater land use diversity and road density than reference sites. The 12-year-old sites
had a higher gradient and a higher percentage of their surrounding area in urban land use. These results show that the created
wetlands were significantly structurally different (if not functionally so) from reference wetlands even after 12 years. The
most profound differences were in hydrology and the characteristics of the surrounding landscape. More attention needs to
be focused on placing created wetlands in appropriate settings to encourage proper hydrodynamics, eliminate habitat fragmentation,
and minimize the effects of stressors to the site. 相似文献
263.
Zhao Ma Dennis R. Becker Michael A. Kilgore 《Journal of Environmental Planning and Management》2009,52(8):1035-1051
Following the intent of the National Environmental Policy Act of 1969, many states have adopted policies and procedures directing state agencies and local government units to evaluate the potential environmental impacts of development projects prior to their undertaking. In contrast to a rich literature on federal requirements, current understanding of state environmental review is narrowly focused and outdated. This paper seeks to provide information on the landscape of state environmental review policy frameworks. The paper identifies 37 states with formal environmental review requirements through a document review of state statutes, administrative rules and agency-prepared materials, and confirms this finding through a survey of state administrators. A two-tier classification is used to distinguish states based on the approach taken to address environmental review needs and the scope and depth of relevant policies and procedures implemented. This paper also provides a discussion of policy and programme attributes that may contribute to effective practice, and of the potential for adopting relevant legislation in states where environmental review is currently lacking. 相似文献
264.
A compilation has been undertaken of data which can be used to derive animal product transfer coefficients for radionuclides, including an extensive review of Russian language information. The resultant database has been used to provide recommended transfer coefficient values for a range of radionuclides to (i) cow, sheep and goat milk, (ii) meat (muscle) of cattle, sheep, goats, pigs and poultry and (iii) eggs. The values are used in a new IAEA handbook on transfer parameters which replaces that referred to as ‘TRS 364’. The paper outlines the approaches and procedures used to identify and collate data, and assumptions used. There are notable differences between the TRS 364 ‘expected’ values and the recommended values in the revised Handbook from the new database. Of the recommended values, three milk values are at least an order of magnitude higher than the TRS 364 values (Cr, Pu (cow) Pu (sheep)) and one milk value is lower (Ni (cow)). For meat, four values (Am, Cd, Sb (beef) I (pork)) are at least an order of magnitude higher than the TRS 364 values and eight values are at least an order of magnitude lower (Ru, Pu (beef), Ru, Sr, Zn (sheep), Ru, Sr (pork), Mn (poultry)). Many data gaps remain. 相似文献
265.
W.J.F. Standring J.E. Brown M. Dowdall E.M. Korobova V.G. Linnik A.G. Volosov 《Journal of environmental radioactivity》2009,100(12):1109
The Mining and Chemical Industrial Combine, Zheleznogorsk (MCIC, previously known as Krasnoyarsk-26) on the River Yenisey has contaminated the surrounding environment with anthropogenic radionuclides as a result of discharges of radioactive wastes. The purpose of this study was to investigate the vertical distribution of anthropogenic contamination (137Cs and plutonium) within floodplain areas at different distances from the discharge point. Sites were chosen that display different characteristics with respect to periodic inundation with river water. Cs-137 activity concentrations were in the range 23–3770 Bq/kg (dry weight, d.w.); Pu-239,240 activity concentrations were in the range <0.01–14.2 Bq/kg (d.w.). Numerous sample cores exhibited sub-surface maxima which may be related to the historical discharges from the MCIC. Possible evidence indicating the deposition of earlier discharges at MCIC in deeper core layers was observed in the 238Pu:239,240Pu activity ratio data: a Pu signal discernible from global fallout could be observed in numerous samples. Cs-137 and Pu-239,240 activity concentrations were correlated with the silt fraction (% by mass <63 μm) though no significant correlation was observed between (grain-size) normalised 137Cs activity concentrations and distance downstream from the MCIC. 相似文献
266.
267.
S. Fesenko N. Isamov B.J. Howard N.A. Beresford C.L. Barnett N. Sanzharova G. Voigt 《Journal of environmental radioactivity》2009
Over 150 publications reporting studies conducted in the former USSR were reviewed to provide transfer coefficients (Ff) to the muscle of domestic animals from experiments using chronic administration, often for long timescales in large scale experiments. Only a few of these studies were made available in the English language literature or taken into account in international reviews. The values derived have been compared with expected values reported by the IAEA's Handbook of parameter values for the prediction of radionuclide transfer in temperate environments (TRS 364) where possible. The information presented here has been used in the current updating of parameters recommended for environmental assessments by the IAEA. Many of the reported values are for Sr due to the Mayak accident and Cs due to the Chernobyl accident. Nevertheless, the reported data for a wide range of radionuclides, in particular for Ru, Sb, and Zn markedly improve the extent of available data. 相似文献
268.
269.
The composition of pied flycatcher (Ficedula hypoleuca Pall.) nestling diet was studied in the zone of strong pollution with emissions from the Middle Ural Copper Smelter (Revda,
Sverdlovsk oblast) and in the background area from 2005 to 2007. The results show that diversity of the diet decreases and
prevalence in it of one insect taxon (Lepidoptera) increases near the source of emissions. The proportion of uncharacteristic
food objects (orthopterans, herpetobiont invertebrates) and variation in the size of invertebrates brought by parents to their
nestlings increase, which is explained by degradation of forest habitats in the polluted area. Pied flycatchers provide nestlings
with sufficient quantities of food, but its quality in the polluted zone is lower than in the background area. 相似文献
270.
A. P. Gusev 《Russian Journal of Ecology》2009,40(3):160-165
Specific features of progressive succession in the vegetation of anthropogenically transformed landscapes in southeastern Belarus have been studied in permanent test plots. Using phytoindication scales proposed by Ellenberg (1974) and Tsyganov (1983), trends of changes in ecological conditions in the first years of succession have been revealed. 相似文献