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41.
MURRAY A. RUDD KAREN F. BEAZLEY STEVEN J. COOKE ERICA FLEISHMAN DANIEL E. LANE MICHAEL B. MASCIA ROBIN ROTH GARY TABOR JISELLE A. BAKKER TERESA BELLEFONTAINE DOMINIQUE BERTEAUX BERNARD CANTIN KEITH G. CHAULK KATHRYN CUNNINGHAM ROD DOBELL ELEANOR FAST NADIA FERRARA C. SCOTT FINDLAY LARS K. HALLSTROM THOMAS HAMMOND LUISE HERMANUTZ JEFFREY A. HUTCHINGS KATHRYN E. LINDSAY TIM J. MARTA VIVIAN M. NGUYEN GREG NORTHEY KENT PRIOR SAUDIEL RAMIREZ‐SANCHEZ JAKE RICE DARREN J. H. SLEEP NORA D. SZABO GENEVIÈVE TROTTIER JEAN‐PATRICK TOUSSAINT JEAN‐PHILIPPE VEILLEUX 《Conservation biology》2011,25(3):476-484
Abstract: Integrating knowledge from across the natural and social sciences is necessary to effectively address societal tradeoffs between human use of biological diversity and its preservation. Collaborative processes can change the ways decision makers think about scientific evidence, enhance levels of mutual trust and credibility, and advance the conservation policy discourse. Canada has responsibility for a large fraction of some major ecosystems, such as boreal forests, Arctic tundra, wetlands, and temperate and Arctic oceans. Stressors to biological diversity within these ecosystems arise from activities of the country's resource‐based economy, as well as external drivers of environmental change. Effective management is complicated by incongruence between ecological and political boundaries and conflicting perspectives on social and economic goals. Many knowledge gaps about stressors and their management might be reduced through targeted, timely research. We identify 40 questions that, if addressed or answered, would advance research that has a high probability of supporting development of effective policies and management strategies for species, ecosystems, and ecological processes in Canada. A total of 396 candidate questions drawn from natural and social science disciplines were contributed by individuals with diverse organizational affiliations. These were collaboratively winnowed to 40 by our team of collaborators. The questions emphasize understanding ecosystems, the effects and mitigation of climate change, coordinating governance and management efforts across multiple jurisdictions, and examining relations between conservation policy and the social and economic well‐being of Aboriginal peoples. The questions we identified provide potential links between evidence from the conservation sciences and formulation of policies for conservation and resource management. Our collaborative process of communication and engagement between scientists and decision makers for generating and prioritizing research questions at a national level could be a model for similar efforts beyond Canada. 相似文献
42.
Establishment Success across Convergent Mediterranean Ecosystems: an Analysis of Bird Introductions 总被引:3,自引:0,他引:3
Abstract: Concern over the impact of invaders on biodiversity and on the functioning of ecosystems has generated a rising tide of comparative analyses aiming to unveil the factors that shape the success of introduced species across different regions. One limitation of these studies is that they often compare geographically rather than ecologically defined regions. We propose an approach that can help address this limitation: comparison of invasions across convergent ecosystems that share similar climates. We compared avian invasions in five convergent mediterranean climate systems around the globe. Based on a database of 180 introductions representing 121 avian species, we found that the proportion of bird species successfully established was high in all mediterranean systems (more than 40% for all five regions). Species differed in their likelihood to become established, although success was not higher for those originating from mediterranean systems than for those from nonmediterranean regions. Controlling for this taxonomic effect with generalized linear mixed models, species introduced into mediterranean islands did not show higher establishment success than those introduced to the mainland. Susceptibility to avian invaders, however, differed substantially among the different mediterranean regions. The probability that a species will become established was highest in the Mediterranean Basin and lowest in mediterranean Australia and the South African Cape. Our results suggest that many of the birds recently introduced into mediterranean systems, and especially into the Mediterranean Basin, have a high potential to establish self-sustaining populations. This finding has important implications for conservation in these biologically diverse hotspots. 相似文献
43.
Abstract: Populations at the margin of geographic ranges of distribution have been considered more vulnerable than central ones, but recent reviews have caste doubt on this generalization. We examined the reproductive and demographic performance of a rare Euroasiatic orchid (Cypripedium calceolus) at its southwesterly range limit and compared our findings with those of previous studies of nine central populations at the center of the orchid's range. We sought to test the central‐marginal model and to evaluate factors involved in long‐term performance of forest Eurosiberian species with peripheral populations in southern European mountains. We characterized (structure, temporal fluctuations, herbivory, reproductive success, and recruitment at different habitats) four Pyrenean populations of C. calceolus of different sizes (5–3500 ramets) and monitored three of them for up to 13 years. Two quantitative stochastic models (count data and matrix models) were used to assess population trends and viability and the effect of herbivory. Contrary to expectations, and despite the negative effect of sporadic events of herbivory, the peripheral populations we studied (except the smallest one) performed similarly or better than populations occurring in central part of the species’ range in terms of reproductive success and population growth rates. Landscape changes over the last 50 years suggest that natural reforestation could be involved in the success of this plant at its southern limit. Forest expansion in the mountain regions of southern Europe may provide new opportunities for plants with geographic distributions centered mainly at higher latitudes and give some hope for their recovery in future scenarios dominated by biodiversity loss. 相似文献
44.
ELISE F. GRANEK DANIEL R. BRUMBAUGH† SCOTT A. HEPPELL‡ SELINA S. HEPPELL‡ DAVID SECORD§ 《Conservation biology》2005,19(4):1008-1018
Abstract: In the first comprehensive reviews since 1969, two high-level reports on the status of U.S. marine ecosystems and resources have been released: that of the nongovernmental Pew Oceans Commission in 2003 and that of the congressionally mandated U.S. Commission on Ocean Policy in 2004 . Although the two commissions differed in the breadth and depth of their mandates, their findings on the state of our oceans and need for new management approaches are similar, and their major recommendations for science, governance, management and conservation, and education echo and reinforce each other. The history behind the two commissions and the structure and objectives of each remind us of the crucial roles conservation practitioners and scientists must play in the implementation of report recommendations. The reports suggest priorities for conservation practitioners to improve science, management, conservation, governance, and education to better manage and protect ocean resources and ecosystems. To redirect activities affecting the state of global marine resources, integrated research; education and outreach by terrestrial, aquatic, and marine conservation practitioners; and a clear definition of their roles in the implementation of recommendations is essential. Marine ecosystems provide a test case of society's ability to manage complexity in human and natural systems in an integrated manner, with extensive opportunities for participation by conservation practitioners from all disciplines. 相似文献
45.
VESNA FURTULA GEORGE DERKSEN ALAN COLODEY 《Journal of environmental science and health. Part. B》2013,48(8):1259-1271
A new approach to surface water analysis has been investigated in order to enhance the detection of different organic contaminants in Nathan Creek, British Columbia. Water samples from Nathan Creek were prepared by liquid/liquid extraction using dichloromethane (DCM) as an extraction solvent and analyzed by gas chromatography mass spectrometry method in scan mode (GC-MS scan). To increase sensitivity for pesticides detection, acquired scan data were further analyzed by Automated Mass Spectrometry Deconvolution and Identification Software (AMDIS) incorporated into the Agilent Deconvolution Reporting Software (DRS), which also includes mass spectral libraries for 567 pesticides. Extracts were reanalyzed by gas chromatography mass spectrometry single ion monitoring (GC-MS-SIM) to confirm and quantitate detected pesticides. Pesticides: atrazine, dimethoate, diazinone, metalaxyl, myclobutanil, napropamide, oxadiazon, propazine and simazine were detected at three sampling sites on the mainstream of the Nathan Creek. Results of the study are further discussed in terms of detectivity and identification level for each pesticide found. The proposed approach of monitoring pesticides in surface waters enables their detection and identification at trace levels. 相似文献
46.
GEORGE F. ANTONIOUS JANET E. MEYER JOHN C. SNYDER 《Journal of environmental science and health. Part. B》2013,48(8):1383-1391
Increasing concern about persistence and environmental impact of synthetic pesticide residues require development of biodegradable and environmentally safe alternatives. The potential of using fruit extracts of hot pepper as alternatives to synthetic acaricides for controlling the two-spotted spider mite, Tetranychus urticae Koch, is explored in this study. Twenty-four Capsicum accessions (Solanaceae) were screened for their toxicity and repellency to the spider mites. Crude extracts from fruits of C. chinense, C. frutescens, C. baccatum, C. annuum, and C. pubescens were prepared in methanol and tested for their acaricidal properties. Spider mite mortality was greatest (45%) when fruit extract of accession Grif-9169 (C. annuum) was used. Results from diving board bioassays indicated that mites avoided filter paper strips treated with hot pepper extracts from accessions PI-596057 (C. baccatum), PI-195299 (C. annuum), and Grif- 9270 (C. annuum). This investigation suggests that methanolic extracts of these three accessions may have a great potential for repelling spider mites and should be field-tested on a large-scale to assess their value in managing populations of spider mites, which could reduce reliance on synthetic acaricides. An attempt was made to correlate repellency with chemical constituents of fruit extracts of the most repellent accessions to identify chemical sources of repellency. Capsaicin and dihydrocapsaicin, the pungent components of pepper fruit, were not correlated with toxicity or repellency, indicating that these are not likely related to the toxicity or repellency of the pepper fruit extracts. Other, unidentified chemicals are likely responsible for toxicity and repellency to the two-spotted spider mite 相似文献
47.
We examine the joint effects of task interdependence and reward interdependence on group behavior and performance. We develop a model that predicts that task and reward interdependence will interact to increase performance, and present results of a laboratory experiment that confirms our prediction. We explore the efficacy of group reward systems for different task designs, and the relationship between cooperation and performance. We confirm earlier results on the weakness of the free-rider effect in small face-to-face groups. We also find, surprisingly, that while reward interdependence is important to performance, task interdependence, but not reward interdependence, drives observed cooperative behavior. This last result suggests caution in interpreting the efficacy of changes in the design of work. Such changes, if unaccompanied by changes in the design of the reward system, are likely to appear successful in terms of observed cooperation, but may not enhance performance. © 1997 by John Wiley & Sons, Ltd. 相似文献
48.
Multiobjective Assessment of Multipurpose Water Resources Projects for Developing Countries 总被引:1,自引:0,他引:1
Multiobjective assessments of water resource projects are useful for widening the range of impacts that are considered during the process of project planning and selection. Some of the principles and problems associated with multiobjective analyses are reviewed, as are several relatively simple information display techniques and approaches found applicable to conditions in many developing countries. These techniques can be used where data and technical expertise are limited, and where it is not possible to identify and quantify all economic, environmental or social objectives and their trade-offs during the search for the best compromise decision. 相似文献
49.
DANIEL DOAK 《Conservation biology》1989,3(4):389-396
Abstract: Northern Spotted Owls, Strix occidentalis caurina, require large tracts of old-growth conifer forest to survive and reproduce. Much of this forest has been or is being cut by commercial logging operations, with uncertain consequences for the owls. In this paper I present simulation models of owl population change over the next 100 years, as summing a variety of scenarios for habitat destruction and fragmentation. My analysis differs from previous models by incorporating patchy territory distribution and random environmental fluctuations. Fragmented and patchy habitat distributions are common problems for endangered organisms, but they have received little attention from modelers. My results indicate that yearly fluctuations in breeding success have little impact on owl populations, but that spatial structure is quite important and should be considered in planning forest preservation. The simulations suggest that for all reasonable parameter values the proposed US. Forest Service logging plans will lead to the demise of the owls. 相似文献
50.
Abstract: Information required to evaluate the extent to which species are at risk of extinction is usually limited and characterized as highly uncertain. In this context, we define information availability as the presence or absence of information used to determine the value of an ecological variable. We examined which of three hypothetical approaches best matched how levels of risk are assigned to species: (1) precautionary approach in which analysts designate levels of risk regardless of the amount of information available, (2) worst‐case approach in which analysts assign the maximum level of risk possible from the criteria, and (3) insurance approach in which analysts assign poorly known species to a high‐risk category when little information is available. We used the quantitative assessment criteria of the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) as a case study. We created a binary (0/1) matrix of all 2.4192 × 107 logical combinations of available information for the 14 ecological variables included in the quantitative criteria. We processed each combination of information availability represented in the matrix with a computer algorithm designed to emulate COSEWIC decision‐making rules. Low information availability was associated with a relatively high frequency of not being able to assign a candidate taxon to a risk category, which does not follow the precautionary principle. Information availability and the level of risk assigned to species were directly related, which is associated with the worst‐case approach, and counter to the insurance approach. Our results suggest that information availability can have a major effect on the level of risk assigned to a species. We recommend a conscious determination of whether such effects are desired, and we recommend the development of methods to explicitly characterize and incorporate information availability and other sources of uncertainty in decision‐making processes. 相似文献