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161.
Cumulative ecological and socioeconomic effects of forest policies in coastal Oregon. 总被引:1,自引:0,他引:1
Thomas A Spies K Norman Johnson Kelly M Burnett Janet L Ohmann Brenda C McComb Gordon H Reeves Pete Bettinger Jeffrey D Kline Brian Garber-Yonts 《Ecological applications》2007,17(1):5-17
Forest biodiversity policies in multi-ownership landscapes are typically developed in an uncoordinated fashion with little consideration of their interactions or possible unintended cumulative effects. We conducted an assessment of some of the ecological and socioeconomic effects of recently enacted forest management policies in the 2.3-million-ha Coast Range Physiographic Province of Oregon. This mountainous area of conifer and hardwood forests includes a mosaic of landowners with a wide range of goals, from wilderness protection to high-yield timber production. We projected forest changes over 100 years in response to logging and development using models that integrate land use change and forest stand and landscape processes. We then assessed responses to those management activities using GIS models of stand structure and composition, landscape structure, habitat models for focal terrestrial and aquatic species, timber production, employment, and willingness to pay for biodiversity protection. Many of the potential outcomes of recently enacted policies are consistent with intended goals. For example, we project the area of structurally diverse older conifer forest and habitat for late successional wildlife species to strongly increase. 'Other outcomes might not be consistent with current policies: for example, hardwoods and vegetation diversity strongly decline within and across owners. Some elements of biodiversity, including streams with high potential habitat for coho salmon (Oncorhynchus kisutch) and sites of potential oak woodland, occur predominately outside federal lands and thus were not affected by the strongest biodiversity policies. Except for federal lands, biodiversity policies were not generally characterized in sufficient detail to provide clear benchmarks against which to measure the progress or success. We conclude that land management institutions and policies are not well configured to deal effectively with ecological issues that span broad spatial and temporal scales and that alternative policies could be constructed that more effectively provide for a mix of forest values from this region. 相似文献
162.
Comparison of fine-scale acoustic monitoring systems using home range size of a demersal fish 总被引:1,自引:0,他引:1
Kelly S. Andrews Nick Tolimieri Greg D. Williams Jameal F. Samhouri Chris J. Harvey Phillip S. Levin 《Marine Biology》2011,158(10):2377-2387
We compared the results from fixed acoustic transmitters and transmitters implanted in lingcod Ophiodon elongatus provided by two fine-scale passive acoustic monitoring systems: the older Vemco? Radio Acoustic Positioning (VRAP) system and the newer VR2W Positioning System (VPS) with either three or four receivers.
The four-receiver VPS method calculated five times more positions of lingcod than VRAP and more than twice as many as the
three-receiver VPS. Calculated positions of fixed transmitters were less precise with VRAP than either VPS approach. Measurements
of home range for lingcod were similar between the four-receiver VPS and VRAP, which were both greater than the three-receiver
VPS. Comparisons varied when lingcod were in/near complex habitats. As new technology develops, it is important to understand
how new methods compare to previous methods. This may be important when describing patterns of movement or habitat use in
the context of changes in habitat or management efforts. 相似文献
163.
Nagy JA Johnson DL Larter NC Campbell MW Derocher AE Kelly A Dumond M Allaire D Croft B 《Ecological applications》2011,21(6):2334-2348
Effective management and conservation of species, subspecies, or ecotypes require an understanding of how populations are structured in space. We used satellite-tracking locations and hierarchical and fuzzy clustering to quantify subpopulations within the behaviorally different barren-ground caribou (Rangifer tarandus groenlandicus), Dolphin and Union island caribou (R. t. groenlandicus x pearyi), and boreal (R. t. caribou) caribou ecotypes in the Northwest Territories and Nunavut, Canada. Using a novel approach, we verified that the previously recognized Cape Bathurst, Bluenose-West, Bluenose-East, Bathurst, Beverly, Qamanirjuaq, and Lorillard barren-ground subpopulations were robust and that the Queen Maude Gulf and Wager Bay barren-ground subpopulations were organized as individuals. Dolphin and Union island and boreal caribou formed one and two distinct subpopulation, respectively, and were organized as individuals. Robust subpopulations were structured by strong annual spatial affiliation among females; subpopulations organized as individuals were structured by migratory connectivity, barriers to movement, and/or habitat discontinuity. One barren-ground subpopulation used two calving grounds, and one calving ground was used by two barren-ground subpopulations, indicating that these caribou cannot be reliably assigned to subpopulations solely by calving-ground use. They should be classified by annual spatial affiliation among females. Annual-range size and path lengths varied significantly among ecotypes, including mountain woodland caribou (R. t. caribou), and reflected behavioral differences. An east-west cline in annual-range sizes and path lengths among migratory barren-ground subpopulations likely reflected differences in subpopulation size and habitat conditions and further supported the subpopulation structure identified. 相似文献
164.
A Decision Support Framework for Science-Based, Multi-Stakeholder Deliberation: A Coral Reef Example 总被引:2,自引:0,他引:2
Amanda P. Rehr Mitchell J. Small Patricia Bradley William S. Fisher Ann Vega Kelly Black Tom Stockton 《Environmental management》2012,50(6):1204-1218
We present a decision support framework for science-based assessment and multi-stakeholder deliberation. The framework consists of two parts: a DPSIR (Drivers–Pressures–States–Impacts–Responses) analysis to identify the important causal relationships among anthropogenic environmental stressors, processes, and outcomes; and a Decision Landscape analysis to depict the legal, social, and institutional dimensions of environmental decisions. The Decision Landscape incorporates interactions among government agencies, regulated businesses, non-government organizations, and other stakeholders. It also identifies where scientific information regarding environmental processes is collected and transmitted to improve knowledge about elements of the DPSIR and to improve the scientific basis for decisions. Our application of the decision support framework to coral reef protection and restoration in the Florida Keys focusing on anthropogenic stressors, such as wastewater, proved to be successful and offered several insights. Using information from a management plan, it was possible to capture the current state of the science with a DPSIR analysis as well as important decision options, decision makers and applicable laws with a the Decision Landscape analysis. A structured elicitation of values and beliefs conducted at a coral reef management workshop held in Key West, Florida provided a diversity of opinion and also indicated a prioritization of several environmental stressors affecting coral reef health. The integrated DPSIR/Decision landscape framework for the Florida Keys developed based on the elicited opinion and the DPSIR analysis can be used to inform management decisions, to reveal the role that further scientific information and research might play to populate the framework, and to facilitate better-informed agreement among participants. 相似文献
165.
Laboratory experiments assessed how bioaccumulation of weathered p,p′-DDE from soil and humic acid (HA) chemistry are affected by interactions between the plants Cucurbita pepo ssp. pepo and ssp. ovifera and the earthworms Eisenia fetida, Lumbricus terrestris, and Apporectodea caliginosa. Total organochlorine phytoextraction by ssp. pepo increased at least 25% in the presence of any of the earthworm species (relative to plants grown in isolation). Uptake of the compound by ssp. ovifera was unaffected by earthworms. Plants influenced earthworm bioaccumulation as well. When combined with pepo, p,p′-DDE levels in E. fetida decreased by 50%, whereas, in the presence of ovifera, bioconcentration by L. terrestris increased by more than 2-fold. Spectral analysis indicated a decrease in hydrophobicity of HA in each of the soils in which both pepo and earthworms were present. However, HA chemistry from ovifera treatments was largely unaffected by earthworms. Risk assessments of contaminated soils should account for species interactions, and SOM chemistry may be a useful indictor of pollutant bioaccumulation. 相似文献
166.
Development of a New Approach to Cumulative Effects Assessment: A Northern River Ecosystem Example 总被引:2,自引:0,他引:2
Dubé M Johnson B Dunn G Culp J Cash K Munkittrick K Wong I Hedley K Booty W Lam D Resler O Storey A 《Environmental monitoring and assessment》2006,113(1-3):87-115
If sustainable development of Canadian waters is to be achieved, a realistic and manageable framework is required for assessing cumulative effects. The objective of this paper is to describe an approach for aquatic cumulative effects assessment that was developed under the Northern Rivers Ecosystem Initiative. The approach is based on a review of existing monitoring practices in Canada and the presence of existing thresholds for aquatic ecosystem health assessments. It suggests that a sustainable framework is possible for cumulative effects assessment of Canadian waters that would result in integration of national indicators of aquatic health, integration of national initiatives (e.g., water quality index, environmental effects monitoring), and provide an avenue where long-term monitoring programs could be integrated with baseline and follow-up monitoring conducted under the environmental assessment process. 相似文献
167.
Consistent effects of nitrogen fertilization on soil bacterial communities in contrasting systems 总被引:11,自引:0,他引:11
Ecosystems worldwide are receiving increasing amounts of reactive nitrogen (N) through anthropogenic activities. Although the effects of increased N inputs on plant communities have been reasonably well studied, few comparable studies have examined impacts on whole soil bacterial communities, though they play critical roles in ecosystem functioning. We sampled soils from two long-term ecological research (LTER) experimental N gradients, both of which have been amended with NH4NO3; a grassland at Cedar Creek (27 years of N additions) and an agricultural field at Kellogg Biological Station (8 years of N additions). By examining shifts in bacterial communities across these contrasting ecosystem types, we could test competing hypotheses about the direct and indirect factors that might drive bacterial responses to elevated N inputs. Bacterial community structure was highly responsive to N additions. We observed predictable and consistent changes in the structure of the bacterial communities across both ecosystem types. Our results suggest that bacterial communities across these gradients are more structured by N and/or soil carbon availability than by shifts in the plant community or soil pH associated with the elevated nitrogen inputs. In contrast to the pronounced shifts in bacterial community composition and in direct contrast to the patterns often observed in plant communities, increases in N availability did not have consistent effects on the richness and diversity of soil bacterial communities. 相似文献
168.
One of the challenges to quantifying the costs and benefits of symbiosis is that symbionts can influence different components of host fitness. To improve understanding of the ecology of inherited symbionts, we developed general theory for a perennial host-hereditary symbiont interaction, in which symbionts can have independent and potentially opposing effects on host regeneration and survival. The model showed that negative effects on one component of fitness may be outweighed by positive effects on another, leading to a net positive impact of symbiosis on population growth. Model predictions depended on the availability of suitable patches, which influenced the relative contributions of survival vs. regeneration to host fitness. We then used experimental symbiont removal to quantify effects of a hereditary, fungal endophyte on a grass host. Endophyte presence strongly reduced host survival but increased regeneration. Application of the model revealed that negative effects on plant survival were overwhelmed by beneficial effects on regeneration, resulting in stable endophyte persistence at 100% frequency, consistent with field observations. Our work demonstrates the utility of a demographic perspective for predicting the dynamics of symbioses and supports the hypothesis that symbionts function as mutualists when host and symbiont fitness are coupled through vertical transmission. 相似文献
169.
Mammalian communities were studied on 10 surface mines over a four year period. The size and composition of these communities varied among the different areas. The size, composition, and spatial distribution of these mammalian communities were related to the structure of the plant community, and native plant species were of greater importance in determining size and composition of these communities than were those used in reclamation. 相似文献
170.
The multiple and interlinked problems that plague most peri-urban communities can only be successfully addressed and resolved if roles and responsibilities of all actors in the urban setting are redistributed. This will require fundamental changes in the way municipalities work and define their accomplishments. Behaviour needs to change at all levels, beginning with public sector institutions responsible for communities. Without changes at the municipal level, requisite changes at the community level to remedy the root causes of environment-related illness, do not occur. Public sector institutions and communities, working as partners with clearly defined roles and responsibilities, and, most importantly, with mutual trust, can together make real progress toward improving health and well-being in peri-urban settlements. This article discusses two recent projects sponsored by the Environmental Health Project of the U.S. Agency for International Development (USAID): an 18-month pilot project to improve peri-urban environmental health in two cities in Tunisia, and a project in Ecuador to support the Ministry of Health in combating cholera in affected provinces. The following examples, methodology, and results may be useful to officials and donor organizations in designing environmental health projects. 相似文献