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801.
Marc Russell John Rogers Stephen Jordan Darrin Dantin James Harvey Janet Nestlerode Federico Alvarez 《Journal of Coastal Conservation》2011,15(4):647-658
The Tampa Bay Ecosystem Services Demonstration Project (TBESDP) is part of the U.S. Environmental Protection Agency’s Ecosystem
Services Research Program. The principal objectives of TBESDP are to (1) quantify the ecosystem services of the Tampa Bay
watershed, (2) determine the value of ecosystem services to society, (3) predict the supply of ecosystem services under future
scenarios of population growth and climate change, and (4) apply this knowledge through models and tools that will support
the best informed environmental decisions possible. The scope and complexity of this project required intensive effort to
establish which services can be quantified by applying existing models, data, and scientific literature and which services
will require supporting research. Research priorities were assessed by: (1) developing and refining conceptual models of major
ecosystems in the Tampa Bay region, (2) gathering input from stakeholders about the relative importance and values of various
ecosystem services, (3) preparing and reviewing a bibliometric analysis of the volume of scientific literature relevant to
the ecosystems and services of interest, and (4) evaluating an integrated analysis of importance, value, and availability
of scientific information. This analysis led us to focus on two research priorities, seagrass-habitat functions as support
for fishery production, and wetlands as regulators of water quality. 相似文献
802.
This study investigated the effect of a process versus a results focus as well as a group versus individual‐based approach to performance appraisals. Four experimental conditions were investigated, with dependent variables of appraisal satisfaction, perceived accuracy of the performance appraisal, expectations of performance improvement, and actual performance. The results showed that a process focus appraisal had a more positive impact than an exclusively results‐oriented appraisal on ratee appraisal satisfaction, perceived appraisal accuracy, and expectations of performance improvement. Subjects receiving process appraisal feedback also showed a greater improvement in actual performance during a subsequent trial compared to subjects that did not receive process feedback. No differences were found between the group‐ and the individual‐based performance appraisal conditions. Implications of these findings for appraisal processes in general, and total quality initiatives in particular, are discussed. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
803.
Baucum Matt John Richard S. Burns William Portney Kent E. Mumpower Jeryl L. 《The Environmentalist》2021,41(2):227-235
Environment Systems and Decisions - There is great value in understanding the public’s reactions to terror attacks, though such reactions pose stark challenges for sound psychological... 相似文献
804.
805.
Ashraf M. El-Sayed John Revell Alfredo Jiménez-Perez Aimee Harper David M. Suckling 《Chemoecology》2016,26(5):187-193
The currant clearwing Synanthedon tipuliformis (Clerck) (Sesiidae) is a worldwide pest of black currants, Ribes nigrum. This moth has been observed to feed on nectar of inflorescences of Canada thistles, Cirsium arvense (L.) Scop. This work was undertaken to identify floral compound(s) produced by Canada thistles inflorescences that mediate the response of the currant clearwing. Floral volatiles were collected during the day and analysed by coupled gas chromatography/electroantennographic detection (GC/EAD) and gas chromatography/mass spectrometry (GC/MS). Three compounds consistently elicited EAD response from moth antennae and were identified by GC/MS as phenylacetaldehyde, methyl salicylate and dimethyl salicylate. When the compounds were tested individually or in various combinations in field trapping experiments, a 3-component blend attracted the largest number of female and male currant clearwings. Subsequent field trapping experiments were conducted to determine the optimal attraction dose for the ternary blend using three loadings of 1, 10 and 100 mg loaded into a polyethylene sachet. The highest catches were in traps baited with the 100 mg loading. In all trials, males and mated females were caught in significant numbers, while very low numbers of virgin females were found in the traps. In recent years the efficacy of mating disruption against currant clearwing has been reported as declining. The new kairomone blend identified in this study can be used with the sex pheromone to provide an effective control option for this important pest. 相似文献
806.
807.
Junhua LI Yue PENG Huazhen CHANG Xiang LI John C. CRITTENDEN Jiming HAO 《Frontiers of Environmental Science & Engineering》2016,10(3):413
Selective catalytic reduction (SCR) of NOx with NH3 is an effective technique to remove NOx from stationary sources, such as coal-fired power plant and industrial boilers. Some of elements in the fly ash deactivate the catalyst due to strong chemisorptions on the active sites. The poisons may act by simply blocking active sites or alter the adsorption behaviors of reactants and products by an electronic interaction. This review is mainly focused on the chemical poisoning on V2O5-based catalysts, environmental-benign catalysts and low temperature catalysts. Several common poisons including alkali/alkaline earth metals, SO2 and heavy metals etc. are referred and their poisoning mechanisms on catalysts are discussed. The regeneration methods of poisoned catalysts and the development of poison-resistance catalysts are also compared and analyzed. Finally, future research directions in developing poisoning resistance catalysts and facile efficient regeneration methods for SCR catalysts are proposed. 相似文献
808.
Holly Fearnbach John W. Durban David K. Ellifrit Janice M. Waite Craig O. Matkin Chris R. Lunsford Megan J. Peterson Jay Barlow Paul R. Wade 《Marine Biology》2014,161(2):459-472
The productive North Pacific waters of the Gulf of Alaska, Aleutian Islands and Bering Sea support a high density of fish-eating “Resident” type killer whales (Orcinus orca), which overlap in distribution with commercial fisheries, producing both direct and indirect interactions. To provide a spatial context for these interactions, we analyzed a 10-year dataset of 3,058 whale photo-identifications from 331 encounters within a large (linear ~4,000 km) coastal study area to investigate the ranging and social patterns of 532 individually identifiable whales photographed in more than one encounter. Although capable of large-scale movements (maximum 1,443 km), we documented ranges generally <200 km, with high site fidelity across summer sampling intervals and also re-sightings during a winter survey. Bayesian analysis of pair-wise associations identified four defined clusters, likely representing groupings of stable matrilines, with distinct ranging patterns, that combined to form a large network of associated whales that ranged across most of the study area. This provides evidence of structure within the Alaska stock of Resident killer whales, important for evaluating ecosystem and fisheries impacts. This network included whales known to depredate groundfish from longline fisheries, and we suggest that such large-scale connectivity has facilitated the spread of depredation. 相似文献
809.
Barnacles in the genus Chelonibia are commensal with a variety of motile marine animals including sea turtles, crustaceans, and sirenians. We conducted a worldwide molecular phylogenetic survey of Chelonibia collected from nearly all known hosts to assess species relationships, host-fidelity, and phylogeographic structure. Using DNA sequences from a protein-coding mitochondrial gene (COI), a mitochondrial rRNA gene (12S), and one nuclear rRNA gene (28S), we found that of four species, three (C. testudinaria, C. patula, and C. manati) are genetically indistinguishable. In addition, we show each utilizes a rare androdioecious mode of reproduction involving complemental males. In contrast, the fourth species (C. caretta), which is hermaphroditic and specializes on turtles, is genetically distinct—leading to the conclusion that the three former taxa are morphotypes of the same species and should be synonymized under C. testudinaria. Phylogenetic analysis resulted in three geographic clades (Atlantic, Indian Ocean/western Pacific, and eastern Pacific) with haplotype parsimony networks revealing no shared haplotypes among geographic regions. Analysis of molecular variance detected significant differences among sequences by region (p < 0.005); conversely, there were no significant differences among sequences when grouped by host or taxonomic designation. Average pairwise genetic distances were lower between the eastern Pacific and Atlantic clades (0.053 ± 0.006) than between the eastern Pacific and Indian Ocean/western Pacific clades (0.073 ± 0.008), suggesting Atlantic and eastern Pacific populations were connected more recently, perhaps until the rise of the Isthmus of Panama. Host use by Chelonibia morphotypes is discussed along with speculation on possible ancestral hosts and support for a “turtle-first” hypothesis. 相似文献
810.
Ground-dwelling sciurids exhibit a continuum of sociality and several models predict levels of sociality within this taxon. Models of ground squirrel sociality predict round-tailed ground squirrels (Xerospermophilus tereticaudus) to be solitary; however, previous behavioral studies suggest round-tailed ground squirrels have a matrilineal social structure. To resolve this discrepancy, we combined behavioral observations with genetic analyses of population structure. We assessed levels of agonistic and amicable behaviors combined with fine-scale population genetic structure of round-tailed ground squirrels in a multi-year study in AZ. Only 45 agonistic and 40 amicable interactions were observed between adults in over 137 h of observations. Overall rates of agonistic or amicable interactions between adults were low (≤0.69/h), with no relationship between relatedness of individuals and rates of either amicable or agonistic interactions. Interactions between juvenile littermates were predominantly amicable. Population substructure was not evident with Bayesian analyses, global or pairwise F ST values; average relatedness among females was not different from males. However, in 2006, the year after a population reduction through targeted animal elimination, a population bottleneck was detected within at least five of seven loci. Contrary to previous behavioral studies, this population of round-tailed ground squirrels, although aggregated spatially, did not exhibit high levels of social behavior nor subpopulation genetic structure. Analyses of the genetic relationships and sociality along a continuum, particularly within aggregates of individuals, may lead to insights into the origin and maintenance of social behaviors by elucidating the mechanisms by which aggregates with intermediate social levels are formed and maintained. 相似文献