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101.
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
102.
Samuli Korpinen Leena Laamanen Lena Bergstrm Marco Nurmi Jesper H. Andersen Juuso Haapaniemi E. Therese Harvey Ciaran J. Murray Monika Peterlin Emilie Kallenbach Katja Klan
nik Ulf Stein Leonardo Tunesi David Vaughan Johnny Reker 《Ambio》2021,50(7):1325
Marine ecosystems are under high demand for human use, giving concerns about how pressures from human activities may affect their structure, function, and status. In Europe, recent developments in mapping of marine habitats and human activities now enable a coherent spatial evaluation of potential combined effects of human activities. Results indicate that combined effects from multiple human pressures are spread to 96% of the European marine area, and more specifically that combined effects from physical disturbance are spread to 86% of the coastal area and 46% of the shelf area. We compare our approach with corresponding assessments at other spatial scales and validate our results with European-scale status assessments for coastal waters. Uncertainties and development points are identified. Still, the results suggest that Europe’s seas are widely disturbed, indicating potential discrepancy between ambitions for Blue Growth and the objective of achieving good environmental status within the Marine Strategy Framework Directive.Supplementary informationThe online version of this article (10.1007/s13280-020-01482-x) contains supplementary material, which is available to authorized users. 相似文献
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106.
Steve Rayner 《Environmental Hazards》2013,12(2):165-172
This paper argues that the rise of risk and formal risk assessment has contributed to the demise of representative democratic politics by displacing public discourses about values with technical justifications for decision making. Furthermore, risk plays a central role in the displacement of governmental responsibility to private sector and NGO actors at the same time as facilitating government control over citizens—the Janus faces1 of governance and governmentality. Arguing that the turn to public participation cannot be the panacea for the present situation, the paper concludes by calling for revitalisation of representative institutions, the development of real-time technology assessment and development of popular connoisseurship of science and technology. 相似文献
107.
Effects of flow regimes altered by dams on survival, population declines, and range-wide losses of California river-breeding frogs 总被引:1,自引:0,他引:1
Kupferberg SJ Palen WJ Lind AJ Bobzien S Catenazzi A Drennan J Power ME 《Conservation biology》2012,26(3):513-524
Widespread alteration of natural hydrologic patterns by large dams combined with peak demands for power and water delivery during summer months have resulted in frequent aseasonal flow pulses in rivers of western North America. Native species in these ecosystems have evolved with predictable annual flood-drought cycles; thus, their likelihood of persistence may decrease in response to disruption of the seasonal synchrony between stable low-flow conditions and reproduction. We evaluated whether altered flow regimes affected 2 native frogs in California and Oregon (U.S.A.) at 4 spatial and temporal extents. We examined changes in species distribution over approximately 50 years, current population density in 11 regulated and 16 unregulated rivers, temporal trends in abundance among populations occupying rivers with different hydrologic histories, and within-year patterns of survival relative to seasonal hydrology. The foothill yellow-legged frog (Rana boylii), which breeds only in flowing water, is more likely to be absent downstream of large dams than in free-flowing rivers, and breeding populations are on average 5 times smaller in regulated rivers than in unregulated rivers. Time series data (range = 8 - 19 years) from 5 populations of yellow-legged frogs and 2 populations of California red-legged frogs (R. draytonii) across a gradient of natural to highly artificial timing and magnitude of flooding indicate that variability of flows in spring and summer is strongly correlated with high mortality of early life stages and subsequent decreases in densities of adult females. Flow management that better mimics natural flow timing is likely to promote persistence of these species and others with similar phenology. 相似文献
108.
AH Savitzky A Mori DA Hutchinson RA Saporito GM Burghardt HB Lillywhite J Meinwald 《Chemoecology》2012,22(3):141-158
Chemical defenses are widespread among animals, and the compounds involved may be either synthesized from nontoxic precursors or sequestered from an environmental source. Defensive sequestration has been studied extensively among invertebrates, but relatively few examples have been documented among vertebrates. Nonetheless, the number of described cases of defensive sequestration in tetrapod vertebrates has increased recently and includes diverse lineages of amphibians and reptiles (including birds). The best-known examples involve poison frogs, but other examples include natricine snakes that sequester toxins from amphibians and two genera of insectivorous birds. Commonalities among these diverse taxa include the combination of consuming toxic prey and exhibiting some form of passive defense, such as aposematism, mimicry, or presumptive death-feigning. Some species exhibit passive sequestration, in which dietary toxins simply require an extended period of time to clear from the tissues, whereas other taxa exhibit morphological or physiological specializations that enhance the uptake, storage, and/or delivery of exogenous toxins. It remains uncertain whether any sequestered toxins of tetrapods bioaccumulate across multiple trophic levels, but multitrophic accumulation seems especially likely in cases involving consumption of phytophagous or mycophagous invertebrates and perhaps consumption of poison frogs by snakes. We predict that additional examples of defensive toxin sequestration in amphibians and reptiles will be revealed by collaborations between field biologists and natural product chemists. Candidates for future investigation include specialized predators on mites, social insects, slugs, and toxic amphibians. Comprehensive studies of the ecological, evolutionary, behavioral, and regulatory aspects of sequestration will require teams of ecologists, systematists, ethologists, physiologists, molecular biologists, and chemists. The widespread occurrence of sequestered defenses has important implications for the ecology, evolution, and conservation of amphibians and reptiles. 相似文献
109.
Dianne L. Watson Euan S. Harvey Ben M. Fitzpatrick Timothy J. Langlois George Shedrawi 《Marine Biology》2010,157(6):1237-1250
Measures of fish abundance, assemblage composition and length were compared when sampled by baited remote underwater stereo-video
(stereo BRUV) and diver-operated stereo-video transects (stereo DOV) at the Houtman Abrolhos Islands and Ningaloo Reef. Species
richness counts were 40% higher on stereo BRUV than stereo DOV. Stereo BRUVs also recorded a greater number of large-bodied
targeted species in higher abundance than stereo DOV (e.g. Lethrinus nebulosus, Plectropomus leopardus) at the Houtman Abrolhos and at Ningaloo Reef. Many non-targeted species were also recorded in greater abundances on stereo
BRUV than stereo DOV (e.g. Coris auricularis, Gymnothorax spp). Stereo DOV transects recorded a greater abundance of some small-bodied Pomacentridae, Labridae and Scaridae species
than did stereo BRUV, particularly at Ningaloo Reef. This study demonstrates that choice of sampling technique for surveys
of reef fish can lead to very different biological interpretations of fish assemblage structure. 相似文献
110.
The polar bear (Ursus maritimus) depends on sea ice for feeding, breeding, and movement. Significant reductions in Arctic sea ice are forecast to continue because of climate warming. We evaluated the impacts of climate change on polar bears in the southern Beaufort Sea by means of a demographic analysis, combining deterministic, stochastic, environment-dependent matrix population models with forecasts of future sea ice conditions from IPCC general circulation models (GCMs). The matrix population models classified individuals by age and breeding status; mothers and dependent cubs were treated as units. Parameter estimates were obtained from a capture-recapture study conducted from 2001 to 2006. Candidate statistical models allowed vital rates to vary with time and as functions of a sea ice covariate. Model averaging was used to produce the vital rate estimates, and a parametric bootstrap procedure was used to quantify model selection and parameter estimation uncertainty. Deterministic models projected population growth in years with more extensive ice coverage (2001-2003) and population decline in years with less ice coverage (2004-2005). LTRE (life table response experiment) analysis showed that the reduction in lambda in years with low sea ice was due primarily to reduced adult female survival, and secondarily to reduced breeding. A stochastic model with two environmental states, good and poor sea ice conditions, projected a declining stochastic growth rate, log lambdas, as the frequency of poor ice years increased. The observed frequency of poor ice years since 1979 would imply log lambdas approximately - 0.01, which agrees with available (albeit crude) observations of population size. The stochastic model was linked to a set of 10 GCMs compiled by the IPCC; the models were chosen for their ability to reproduce historical observations of sea ice and were forced with "business as usual" (A1B) greenhouse gas emissions. The resulting stochastic population projections showed drastic declines in the polar bear population by the end of the 21st century. These projections were instrumental in the decision to list the polar bear as a threatened species under the U.S. Endangered Species Act. 相似文献