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Species Protection (species + protection)
Selected AbstractsToxicity of brominated volatile organics to freshwater biotaENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2010Monique T. Binet Abstract As part of a larger study investigating the fate and effects of brominated volatile organic compounds (VOCs) in contaminated groundwaters discharging to surface waters, the toxicity of 1,2 dibromoethene (DBE) and 1,1,2-tribromoethene (TriBE) to freshwater aquatic biota was investigated. Their toxicity to bacteria (Microtox®), microalgae (Chlorella sp.), cladocerans (Ceriodaphnia dubia), duckweed (Lemna sp.) and midges (Chironomus tepperi) was determined after careful optimization of the test conditions to minimize chemical losses throughout the tests. In addition, concentrations of DBE and TriBE were carefully monitored throughout the bioassays to ensure accurate calculation of toxicity values. 1,2-Dibromoethene showed low toxicity to most species, with concentrations to cause 50% lethality or effect (LC/EC50 values) ranging from 28 to 420,mg/L, 10% lethality or effect (LC/EC10 values) ranging from 18 to 94,mg/L and no-observed-effect concentrations (NOECs) ranging from 22 to 82,mg/L. 1,1,2-Tribromoethene was more toxic than DBE, with LC/EC50 values of 2.4 to 18,mg/L, LC/EC10 values of 0.94 to 11,mg/L and NOECs of 0.29 to 13,mg/L. Using these limited data, together with data from the only other published study on TriBE, moderate-reliability water quality guidelines (WQGs) were estimated from species sensitivity distributions. The proposed guideline trigger values for 95% species protection with 50% confidence were 2,mg/L for DBE and 0.03,mg/L for TriBE. The maximum concentrations of DBE and TriBE in nearby surface waters (3 and 1,µg /L, respectively) were well below these WQGs, so the risk to the freshwater environment receiving contaminated groundwater inflows was considered to be low, with hazard quotients <1 for both VOCs. Environ. Toxicol. Chem. 2010;29:1984,1993. © 2010 SETAC [source] Recommendations for Integrating Restoration Ecology and Conservation Biology in Ponderosa Pine Forests of the Southwestern United StatesRESTORATION ECOLOGY, Issue 1 2006Reed F. Noss Abstract Over the past century, ponderosa pine,dominated landscapes of the southwestern United States have been altered by human activities such as grazing, timber harvest, road building, and fire exclusion. Most forested areas within these landscapes now show increased susceptibility to stand-replacing fires, insect outbreaks, and drought-related mortality. Recent large wildfires in the region have spurred public interest in large-scale fuel reduction and restoration programs, which create perceived and real conflicts with the conservation of biodiversity. Conservation concerns include the potential for larger road networks, soil and understory disturbance, exotic plant invasion, and the removal of large trees in treated areas. Pursuing prescribed burning, thinning, or other treatments on the broad scale that many scientists and managers envision requires the reconciliation of ecological restoration with biodiversity conservation. This study presents recommendations from a workshop for integrating the principles and practices of restoration ecology and conservation biology, toward the objective of restoring the composition, structure, and function of dry ponderosa pine forests. Planning on the scale of hundreds of thousands of hectares offers opportunities to achieve multiple objectives (e.g., rare species protection and restoration of ecological structures and processes) that cannot easily be addressed on a site-by-site basis. However, restoration must be coordinated with conservation planning to achieve mutual objectives and should include strict guidelines for protection of rare, declining, and sensitive habitats and species. [source] Notes on coastal lagoon typology in the light of the EU Water Framework Directive: Italy as a case studyAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 5 2006Davide Tagliapietra Abstract 1.The European Water Framework Directive (WFD) requires that Member States differentiate the transitional water bodies into types. 2.WFD assigns coastal lagoons to two different water categories, ,transitional waters' and ,coastal waters' on the basis of freshwater influence. 3.The main physical factors that contribute to the genesis and characterization of coastal lagoons are coastal typology, tidal range and climate. 4.Italian lagoons are presented as an example of how these physical factors can be used in coastal lagoon characterization and typology. On this basis, a clear distinction of Italian lagoons into two main groups is possible: Northern Adriatic and Mediterranean. 5.Large lagoons can be profitably subdivided into a hierarchical system of sub-basins facilitating both the comparison of parts of the same lagoon and the comparison between different lagoons. 6.The basins are consistent water bodies that can be used as managerial units for environmental conservation, species protection and wise use of resources. Copyright © 2006 John Wiley & Sons, Ltd. [source] Wildlife trade and endangered species protectionAUSTRALIAN JOURNAL OF AGRICULTURAL & RESOURCE ECONOMICS, Issue 4 2004Paul C. Missios Markets for endangered species potentially generate incentives for both legal supply and poaching. To deter poaching, governments can spend on enforcement or increase legal harvesting to reduce the return from poaching. A leader,follower commitment game is developed to examine these choices in the presence of illegal harvesting and the resulting impacts on species stocks. In addition, current trade restrictions imposed under the Convention on International Trade in Endangered Species of Wild Fauna and Flora are examined. With Cournot conjectures among poachers, the model details the subgame perfect equilibrium interactions between poaching levels, enforcement and legal harvesting. [source] | ||||||||||