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131.
Perceptions of Species Abundance,Distribution, and Diversity: Lessons from Four Decades of Sampling on a Government-Managed Reserve 总被引:2,自引:0,他引:2
J. Whitfield Gibbons
Author to whom correspondence should be addressed. Vincent J. Burke Jeffrey E. Lovich Raymond D. Semlitsch Tracey D. Tuberville J. Russell Bodie Judith L. Greene Peter H. Niewiarowski Howard H. Whiteman David E. Scott Joseph H. K. Pechmann Christopher R. Harrison Stephen H. Bennett John D. Krenz Mark S. Mills Kurt A. Buhlmann John R. Lee Richard A. Seigel Anton D. Tucker Tony M. Mills Trip Lamb Michael E. Dorcas Justin D. Congdon Michael H. Smith David H. Nelson M. Barbara Dietsch Hugh G. Hanlin Jeannine A. Ott Deno J. Karapatakis 《Environmental management》1997,21(2):259-268
/ We examined data relative to species abundance, distribution, anddiversity patterns of reptiles and amphibians to determine how perceptionschange over time and with level of sampling effort. Location data werecompiled on more than one million individual captures or observations of 98species during a 44-year study period on the US Department of Energy's(DOE) Savannah River Site National Environmental Research Park (SRS-NERP) inSouth Carolina. We suggest that perceptions of herpetofaunal speciesdiversity are strongly dependent on level of effort and that land managementdecisions based on short-term data bases for some faunal groups could resultin serious errors in environmental management. We provide evidence thatacquiring information on biodiversity distribution patterns is compatiblewith multiyear spatially extensive research programs and also provide aperspective of what might be achieved if long-term, coordinated researchefforts were instituted nationwide.To conduct biotic surveys on government-managed lands, we recommend revisionsin the methods used by government agencies to acquire and report biodiversitydata. We suggest that government and industry employees engaged inbiodiversity survey efforts develop proficiency in field identification forone or more major taxonomic groups and be encouraged to measure the status ofpopulations quantitatively with consistent and reliable methodologies. Wealso suggest that widespread academic cooperation in the dissemination ofinformation on regional patterns of biodiversity could result byestablishment of a peer-reviewed, scientifically rigorous journal concernedwith status and trends of the biota of the United States. KEY WORDS: Abundance; Amphibian; Biodiversity; Distribution; Landmanagement; Reptile 相似文献
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135.
Anton Koch 《Die Naturwissenschaften》1950,37(14):313-317
136.
Anton Paulrud 《Journal of Environmental Planning and Management》2004,47(6):863-879
In addition to its empirical results, this paper makes three distinct contributions to the literature on valuing fishing recreation by stated preference methods. In particular, the paper proposes a new approach to designing a choice experiment, called ‘approximate minimax design’. It employs the latest advances in optimal design theory and is much easier to compute than the ordinary minimax design. Second, the choice‐experiments are embedded in a trip frequency model, such that the changes in trip frequency can be predicted from improved fish management. Most importantly, the approach proposed in the paper provides a first step in developing dynamic fish management models, because the policies analysed may change the age‐structure of the stock. The paper also contributes with new results on anglers' valuations of angling site characteristics. They conform to traditionally obtained results but also show some unexpected results. In particular, the result does not indicate a difference in the valuation of the species caught. As expected, the application shows that the marginal value of trophy‐fish is high. 相似文献
137.
This study is the first report of post-nesting migrations of loggerhead sea turtles (Caretta caretta) nesting in Sarasota County (Florida, USA), their most important rookery in the Gulf of Mexico (GOM). In total, 28 females
(curved carapace length CCL between 82.2 and 112.0 cm) were satellite-tracked between May 2005 and December 2007. Post-nesting
migrations were completed in 3–68 days (mean ± SD = 23 ± 16 days). Five different migration patterns were observed: six turtles
remained in the vicinity of their nesting site while the other individuals moved either to the south-western part of the Florida
Shelf (n = 9 turtles), the Northeast GOM (n = 2 turtles), the South GOM (Yucatán Shelf and Campeche Bay, Mexico, and Cuba; n = 5 turtles) or the Bahamas (n = 6 turtles). In average, turtles moved along rather straight routes over the continental shelf but showed more indirect
paths in oceanic waters. Path analyses coupled with remote sensing oceanographic data suggest that most of long-distance migrants
reached their intended foraging destinations but did not compensate for the deflecting action of ocean currents. While six
out of seven small individuals (CCL < 90 cm) remained on the Florida Shelf, larger individuals showed various migration strategies,
staying on the Florida Shelf or moving to long-distance foraging grounds. This study highlights the primary importance the
Western Florida Shelf in the management of the Florida Nesting Subpopulation, as well as the need of multi-national effort
to promote the conservation of the loggerhead turtle in the Western Atlantic.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
138.
Claas Hiebenthal Eva E. R. Philipp Anton Eisenhauer Martin Wahl 《Marine Biology》2013,160(8):2073-2087
Acidification of the World’s oceans may directly impact reproduction, performance and shell formation of marine calcifying organisms. In addition, since shell production is costly and stress in general draws on an organism’s energy budget, shell growth and stability of bivalves should indirectly be affected by environmental stress. The aim of this study was to investigate whether a combination of warming and acidification leads to increased physiological stress (lipofuscin accumulation and mortality) and affects the performance [shell growth, shell breaking force, condition index (Ci)] of young Mytilus edulis and Arctica islandica from the Baltic Sea. We cultured the bivalves in a fully-crossed 2-factorial experimental setup (seawater (sw) pCO2 levels “low”, “medium” and “high” for both species, temperature levels 7.5, 10, 16, 20 and 25 °C for M. edulis and 7.5, 10 and 16 °C for A. islandica) for 13 weeks in summer. Mytilus edulis and A. islandica appeared to tolerate wide ranges of sw temperature and pCO2. Lipofuscin accumulation of M. edulis increased with temperature while the Ci decreased, but shell growth of the mussels only sharply decreased while its mortality increased between 20 and 25 °C. In A. islandica, lipofuscin accumulation increased with temperature, whereas the Ci, shell growth and shell breaking force decreased. The pCO2 treatment had only marginal effects on the measured parameters of both bivalve species. Shell growth of both bivalve species was not impaired by under-saturation of the sea water with respect to aragonite and calcite. Furthermore, independently of water temperatures shell breaking force of both species and shell growth of A. islandica remained unaffected by the applied elevated sw pCO2 for several months. Only at the highest temperature (25 °C), growth arrest of M. edulis was recorded at the high sw pCO2 treatment and the Ci of M. edulis was slightly higher at the medium sw pCO2 treatment than at the low and high sw pCO2 treatments. The only effect of elevated sw pCO2 on A. islandica was an increase in lipofuscin accumulation at the high sw pCO2 treatment compared to the medium sw pCO2 treatment. Our results show that, despite this robustness, growth of both M. edulis and A. islandica can be reduced if sw temperatures remain high for several weeks in summer. As large body size constitutes an escape from crab and sea star predation, this can make bivalves presumably more vulnerable to predation—with possible negative consequences on population growth. In M. edulis, but not in A. islandica, this effect is amplified by elevated sw pCO2. We follow that combined effects of elevated sw pCO2 and ocean warming might cause shifts in future Western Baltic Sea community structures and ecosystem services; however, only if predators or other interacting species do not suffer as strong from these stressors. 相似文献
139.
Mikhail Yu Semenov Irina I. Marinaite Natalia A. Zhuchenko Anton V. Silaev Konstantin E. Vershinin Yuri M. Semenov 《Chemistry and Ecology》2018,34(10):925-940
The concentrations of polycyclic aromatic hydrocarbons (PAH), total carbon (TC), total organic carbon (TOC), total nitrogen (TN) and dissolved inorganic nitrogen (DIN) in water and sediments of Lake Baikal and its tributaries were measured. It was found that according to existing water and sediment quality standards limiting permissible PAH concentrations, both surface waters and sediments in Lake Baikal watershed can be considered as unpolluted with PAHs compounds. Nevertheless, the spatial distribution of PAH concentrations in lake water indicates the existence of some point PAH sources in and around the lake. These sources were natural oil seeps and communal facilities such as residential coal-fired and oil-fired boilers. It was observed that concentrations of PAHs in both water and sediments are controlled by organic matter content and organic matter mineralisation degree, as indicated by PAH-to-carbon and nitrogen-to-carbon ratios respectively. It was found that PAH/TOC and PAH/TC ratios characterise PAH loading on water and sediments respectively, whereas DIN/TOC and TN/TC ratios characterise self-purification of water and sediments respectively. It was proved that PAH/TOC and DIN/TOC ratios can be used as tracers to evaluate the PAH contributions from tributaries to Lake Baikal. 相似文献
140.
Collapse of a pollination web in small conservation areas 总被引:6,自引:0,他引:6
A suspected global decline in pollinators has heightened interest in their ecological significance. In a worst-case scenario, the decline of generalist pollinators is predicted to trigger cascades of linked declines among the multiple specialist plant species to which they are linked, but this has not been documented. I studied a portion of a pollination web involving a generalist pollinator, the oil-collecting bee Rediviva peringueyi, and a community of oil-secreting plants. Across 27 established conservation areas located in the Cape Floral Region, I found substantial variation in the bees' occurrence in relation to soil type and the successional stage of the vegetation. Anthropogenic declines were detectable against this background of naturally occurring variation: R. peringueyi was absent from small conservation areas (< 385 ha) in an urban matrix. In the absence of the bee, seed set failed in six specialist plant species that are pollinated only by R. peringueyi but remained high in a pollination generalist, which had replacement pollinators. The findings are consistent with theoretical predictions of the importance of generalist pollinators in maintaining the structure of pollination webs. 相似文献