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191.
Coral reefs are highly dynamic and productive marine ecosystems, providing habitat and refuge for an enormous number of species
including fish, invertebrates and algae. With increased anthropogenic pressures and global climate change, many coral reefs
are rapidly declining. Currently, there is limited knowledge on condition and community assemblage composition of shallow
fringing coral reefs along the south-eastern coast of Queensland, Australia. With increased demand to determine existence
of coastal fringing reefs by National Regional Management groups, a rapid cost effective method to determine reef composition
and condition was required. The aim of this study was to determine the benthic structure and extent of two small coastal fringing
reefs (Hummock Hill Reef and Stringers Reef) along the Southern Great Barrier Reef. Reef substrate assessments were carried
out using a rapid assessment technique and a Point Intercept Method (PIM). The data were analysed and classified using a Geographic
Information System (GIS). Percent substrate cover was calculated using a visual basic image analysis program. The Point intercept
method showed higher accuracy over the rapid assessment technique (up to 15–40% difference) and was thus deemed a more suitable
classification tool for reefs with high structural complexity and heterogeneity. This study focused on piloting a rapid, cost
effective Point Intercept Technique using random point count methodology to document coral benthic habitat and extent over
a commonly used rapid assessment method as a tool for reef coastal management and conservation. The two techniques were compared
and substrate classification success, limitations and errors were discussed. 相似文献
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193.
Wayne M. Getz Dorothea Brückner Thomas R. Parisian 《Behavioral ecology and sociobiology》1982,10(4):265-270
Summary Experimental hives obtained from cordovan queens that were instrumentally inseminated with semen from one cordovan and one Italian drone were set up and allowed to swarm. Cordovan provides a resessive genetic marker system (cuticle color) so that the workers from the cordovan and Italian male lines are distinguishable. Our results show that these patrilineal worker groups segregate non-randomly during colony fission and this segregation cannot be explained by observed age structure. Evidence of innate kin recognition in bees has been previously established. We argue that kin recognition could be responsible for the observed non-random grouping of kin during swarming. 相似文献
194.
Burger J Myers O Boring CS Dixon C Jeitner JC Leonard J Lord C McMahon M Ramos R Shukla S Gochfeld M 《Environmental monitoring and assessment》2003,89(3):285-303
There are important linkages between the health of humans and theenvironment, restoration of degraded lands, and long-term stewardship of public lands, yet most environmental indicators deal only with assessing the physical and biological aspects ofecosystems. In this article, we examine the ratings of perceptionsof several environmental problems for their utility as indicatorsof environmental quality, and examine perceptions of future land use by people interviewed in Santa Fe, New Mexico, near the Department of Energy's (DOE) Los Alamos National Laboratory (LANL). Overall, people with lower incomes rated environmental problems as more severe than others, were more willing to spend federal funds to solve them, and were consistent in their ratingsof severity of environmental problems and their willingness to spend federal funds. Cleaning up LANL and other Department of Energy sites, received the highest rating for expenditure of federal funds. The highest rated future uses for DOE sites were for recreation and for National Environmental Research Parks. People with less education generally gave higher ratings to mostfuture land uses for DOE than did those with more education. However, those with higher education gave higher ratings to nuclear reprocessing, and nuclear material storage. Where there were differences, the people interviewed at Santa Fe rated all environmental problems (except pesticides) as more severe than did those previously interviewed in Albuquerque (located fartherfrom the LANL site), and they were more willing to spend federalfunds on these problems. Ratings for all future land uses did notdiffer between the Santa Fe and Albuquerque respondents. These perception-based indicators show general agreement among peopleliving close and farther away from LANL with respect to cleaningup LANL and the future land uses for the site. These indicators should be considered by regulators, site personnel, and policy makers in future management and land use decisions. 相似文献
195.
In their seminal model of work–family enrichment, Greenhaus and Powell (2006) theorized five categories of work resources to have an impact on work–family enrichment. Using a matched set of 351 dual‐career spouses, we explored how these unique work resources contribute to work–family enrichment and how they spill over to shape job incumbents' family outcomes and cross over to spouse outcomes. Results support indirect effects for the work resources of developmental experiences, supervisor support, schedule control, and self‐efficacy, but not salary, on marital satisfaction and family functioning through the job incumbent's work–family enrichment. In addition, we found support for the crossover of these indirect effects to the spouse through the spouse's positive crossover transmission, which facilitated the spouse's marital satisfaction and commitment to the job incumbent's organization. Our results suggest that multiple work resources have an impact on work–family enrichment and that the flow of positive work resources through work–family enrichment spills over to impact outcomes for the job incumbent and crosses over to the spouse. 相似文献
196.
Paul W. Hadley Peter Gathungu Juan T. Koponen Perry Myers Jesus I. Sotelo 《补救:环境净化治理成本、技术与工艺杂志》2014,24(4):7-26
In 1976, the discovery of the Love Canal Superfund Site in New York thrust environmental cleanups into the forefront of the national conscience and essentially launched the remediation industry. Since then, vast efforts have been devoted to improving site remediation. Despite the attention given to key subject areas, such as site characterization, risk assessment, and remediation technologies, relatively little attention has been given to the objectives set forth for conducting cleanups, and they have generally not been rigorously evaluated in the literature. Several of the more common objectives for remediation projects are discussed. © 2014 Wiley Periodicals, Inc. 相似文献
197.
Quantitative tools for implementing the new definition of significant portion of the range in the U.S. Endangered Species Act 下载免费PDF全文
Julia E. Earl Sam Nicol Ruscena Wiederholt Jay E. Diffendorfer Darius Semmens D. T. Tyler Flockhart Brady J. Mattsson Gary McCracken D. Ryan Norris Wayne E. Thogmartin Laura López‐Hoffman 《Conservation biology》2018,32(1):35-49
In 2014, the Fish and Wildlife Service (FWS) and National Marine Fisheries Service announced a new policy interpretation for the U.S. Endangered Species Act (ESA). According to the act, a species must be listed as threatened or endangered if it is determined to be threatened or endangered in a significant portion of its range (SPR). The 2014 policy seeks to provide consistency by establishing that a portion of the range should be considered significant if the associated individuals’ “removal would cause the entire species to become endangered or threatened.” We reviewed 20 quantitative techniques used to assess whether a portion of a species’ range is significant according to the new guidance. Our assessments are based on the 3R criteria—redundancy (i.e., buffering from catastrophe), resiliency (i.e., ability to withstand stochasticity), and representation (i.e., ability to evolve)—that the FWS uses to determine if a species merits listing. We identified data needs for each quantitative technique and considered which methods could be implemented given the data limitations typical of rare species. We also identified proxies for the 3Rs that may be used with limited data. To assess potential data availability, we evaluated 7 example species by accessing data in their species status assessments, which document all the information used during a listing decision. In all species, an SPR could be evaluated with at least one metric for each of the 3Rs robustly or with substantial assumptions. Resiliency assessments appeared most constrained by limited data, and many species lacked information on connectivity between subpopulations, genetic variation, and spatial variability in vital rates. These data gaps will likely make SPR assessments for species with complex life histories or that cross national boundaries difficult. Although we reviewed techniques for the ESA, other countries require identification of significant areas and could benefit from this research. 相似文献
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Robert L. Myers 《Journal of the Air & Waste Management Association (1995)》2013,63(12):816-817
The industrial scientist-engineer is characterized by a high level of interest in solving problems, with the honest expectation that a novel solution to a problem will be rewarded by society with attendant economic benefits to his employer and to himself. Markets for new and improved emission control equipment and techniques are being created by the ever increasing public awareness of the consequences of continuing air pollution and suggest that new emission-free processes and manufacturing techniques and products will similarly find ready acceptance if not outright demand. 相似文献