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321.
Adapting to Climate Change on Western Public Lands: Addressing the Ecological Effects of Domestic, Wild, and Feral Ungulates 总被引:2,自引:2,他引:0
Robert L. Beschta Debra L. Donahue Dominick A. DellaSala Jonathan J. Rhodes James R. Karr Mary H. O’Brien Thomas L. Fleischner Cindy Deacon Williams 《Environmental management》2013,51(2):474-491
Climate change affects public land ecosystems and services throughout the American West and these effects are projected to intensify. Even if greenhouse gas emissions are reduced, adaptation strategies for public lands are needed to reduce anthropogenic stressors of terrestrial and aquatic ecosystems and to help native species and ecosystems survive in an altered environment. Historical and contemporary livestock production—the most widespread and long-running commercial use of public lands—can alter vegetation, soils, hydrology, and wildlife species composition and abundances in ways that exacerbate the effects of climate change on these resources. Excess abundance of native ungulates (e.g., deer or elk) and feral horses and burros add to these impacts. Although many of these consequences have been studied for decades, the ongoing and impending effects of ungulates in a changing climate require new management strategies for limiting their threats to the long-term supply of ecosystem services on public lands. Removing or reducing livestock across large areas of public land would alleviate a widely recognized and long-term stressor and make these lands less susceptible to the effects of climate change. Where livestock use continues, or where significant densities of wild or feral ungulates occur, management should carefully document the ecological, social, and economic consequences (both costs and benefits) to better ensure management that minimizes ungulate impacts to plant and animal communities, soils, and water resources. Reestablishing apex predators in large, contiguous areas of public land may help mitigate any adverse ecological effects of wild ungulates. 相似文献
322.
Dimitrios Zekkos George A. Athanasopoulos Jonathan D. Bray Athena Grizi Andreas Theodoratos 《Waste management (New York, N.Y.)》2010,30(8-9):1544-1555
Large direct shear testing (300 mm × 300 mm box) of municipal solid waste (MSW) collected from a landfill located in the San Francisco Bay area was performed to gain insight on the shear response of MSW. The study investigated the effects of waste composition, confining stress, unit weight, and loading rate on the stress–displacement response and shear strength of MSW. The amount and orientation of the fibrous waste materials in the MSW were found to play a critical role. The fibrous material had little effect on the MSW’s strength when it was oriented parallel to the shear surface, as is typically the case when waste material is compressed vertically and then tested in a direct shear apparatus. Tests in which the fibrous material was oriented perpendicular to the horizontal shear surface produced significantly stronger MSW specimens. The test results indicate that confining stress and loading rate are also important factors. Based on 109 large-scale direct shear tests, the shear strength of MSW at low moisture contents is best characterized by cohesion = 15 kPa, friction angle = 36° at a normal stress of 1 atmosphere, and a decrease in the friction angle of 5° for every log-cycle increase in normal stress. 相似文献
323.
Sebastian Theis Jonathan L.W. Ruppert Karling N. Roberts Charles K. Minns Marten Koops Mark S. Poesch 《Conservation biology》2020,34(1):41-53
Land-use change via human development is a major driver of biodiversity loss. To reduce these impacts, billions of dollars are spent on biodiversity offsets. However, studies evaluating offset project effectiveness that examine components such as the overall compliance and function of projects remain rare. We reviewed 577 offsetting projects in freshwater ecosystems that included the metrics project size, type of aquatic system (e.g., wetland and creek), offsetting measure (e.g., enhancement, restoration, and creation), and an assessment of the projects’ compliance and functional success. Project information was obtained from scientific and government databases and gray literature. Despite considerable investment in offsetting projects, crucial problems persisted. Although compliance and function were related to each other, a high level of compliance did not guarantee a high degree of function. However, large projects relative to area had better function than small projects. Function improved when projects targeted productivity or specific ecosystem features and when multiple complementary management targets were in place. Restorative measures were more likely to achieve targets than creating entirely new ecosystems. Altogether the relationships we found highlight specific ecological processes that may help improve offsetting outcomes. 相似文献
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Behavioral Ecology and Sociobiology - Animals are often confronted with more sensory stimuli than they can attend to, and so should pay attention to stimuli that are relevant to them and habituate... 相似文献
326.
Peter J. Peterson Mazlin bin Mokhtar Cheryl Chang Jonathan Krueger 《Journal of environmental management》2010,91(5):1202-1208
This paper briefly outlines the United Nations Globally Harmonized System of Classification and Labelling of Chemicals (GHS) and what is meant by GHS implementation in terms of policy-related information for decision-makers plus a framework of actions to enable such policies to be effectively undertaken. The paper discusses the need for simple indicators to measure progress with GHS implementation. Two groups of indicators have been described that comprehensively reflect basic components of GHS implementation. The first group was presented as aggregated indicators or indices, for national capability evaluation. Indicators to evaluate management performance linked to stated objectives were presented as the second group. Information from an Organisation for Economic Co-operation and Development (OECD) published questionnaire on GHS implementation and a questionnaire by the Intergovernmental Forum on Chemical Safety (IFCS) on chemical safety that included GHS have provided the basic information for applying the management capability indicators approach. Through the use of information in these two questionnaires, country-relevant and regional progress with GHS implementation was illustrated. Despite the GHS implementation target of 2008 set by the Johannesburg Plan of Implementation, very few countries have reported they have achieved this target. The simple management indicators proposed in this paper are based on adoption of a questionnaire and a numerical scoring system that could be used to chart progress towards GHS implementation. It was concluded, therefore, that the use of indicators as described in this paper does provide a quick survey of the overall situation in a country and facilitates comparison between countries across regions in terms of GHS implementation. Furthermore such results may indicate which countries require additional assistance with GHS implementation thus strengthening policies and actions across all sectors and involving governments, business, trade, and civil society. 相似文献
327.
Tina Heger Anna T. Pahl Zoltan Botta-Dukát Francesca Gherardi Christina Hoppe Ivan Hoste Kurt Jax Leena Lindström Pieter Boets Sylvia Haider Johannes Kollmann Meike J. Wittmann Jonathan M. Jeschke 《Ambio》2013,42(5):527-540
Invasion ecology has much advanced since its early beginnings. Nevertheless, explanation, prediction, and management of biological invasions remain difficult. We argue that progress in invasion research can be accelerated by, first, pointing out difficulties this field is currently facing and, second, looking for measures to overcome them. We see basic and applied research in invasion ecology confronted with difficulties arising from (A) societal issues, e.g., disparate perceptions of invasive species; (B) the peculiarity of the invasion process, e.g., its complexity and context dependency; and (C) the scientific methodology, e.g., imprecise hypotheses. To overcome these difficulties, we propose three key measures: (1) a checklist for definitions to encourage explicit definitions; (2) implementation of a hierarchy of hypotheses (HoH), where general hypotheses branch into specific and precisely testable hypotheses; and (3) platforms for improved communication. These measures may significantly increase conceptual clarity and enhance communication, thus advancing invasion ecology. 相似文献
328.
329.
Hengrui Tao Jia Xing Gaofeng Pan Jonathan Pleim Limei Ran Shuxiao Wang Xing Chang Guojing Li Fei Chen Junhua Li 《Frontiers of Environmental Science & Engineering》2022,16(4):44
330.
Pitchamani Godwyn-Paulson Ponniah Jonathan Muthuswamy Rodríguez-Espinosa Pedro Francisco Roy Priyadarsi Debajyoti Sánchez-Núñez Juan Manuel Villegas Lorena Elizabeth Campos Rodríguez-González Francisco Márquez-Herrera Ciro Eliseo 《Environmental science and pollution research international》2022,29(41):61698-61710
Environmental Science and Pollution Research - The vertical distribution pattern and concentrations of elements (Fe, Al, Ca, Mg, Mn, Cr, Cu, Ni, Co, Pb, Zn, and As) in the estuarine and lagoon... 相似文献