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671.
Walter Wheaton Dimmick †‡ Michael J. Ghedotti † Michael J. Grose † Anne M. Maglia † Daniel J. Meinhardt † and David S. Pennock 《Conservation biology》1999,13(3):653-660
Abstract: Conservation biology is linked inextricably with systematic biology. The principles of systematic biology, however, have not been integrated completely into the practice and principles of conservation biology. Systematists have recognized for some time that a number of evolutionary processes lead to the diversification of lineages. Yet some present units of conservation, such as the evolutionarily significant unit ( Waples 1991), primarily emphasize only one of these processes, adaptation. Allopatric speciation produces biodiversity without requiring any adaptive shift (and consequent adaptive differences between daughter species), so definitions of conservation units that emphasize adaptation may underestimate biodiversity. We estimated the frequency of different modes of speciation for three groups of vertebrates. The frequency of allopatric speciation varies among these groups, but is an important type of speciation in two of the three groups studied. Our results, and the results of other published studies of the frequency of modes of speciation, demonstrate that any unit of conservation defined solely in terms of adaptation is likely to underestimate biological diversity. 相似文献
672.
Jesper Luxh?i Sander Bruun Lars Stoumann Jensen Jakob Magid Anne Jensen Thomas Larsen 《Waste management & research》2007,25(2):170-176
Application of municipal solid waste (MSW) to arable land can be used to close the nutrient cycle between urban and rural areas. The aim of the current study was to quantify net N mineralization and respiration from composted MSW (CMSW) and anaerobically digested MSW (ADMSW) applied to soil, and to test whether a simple relationship between net N mineralization and respiration that was developed for plant materials, was applicable for these types of MSW. In a laboratory experiment, CMSW and ADMSW were incorporated into soil and incubated at 15 degrees C. During the 149-day experiment, netN mineralization and respiration were determined. Cumulative respiration derived from both MSW types was very steep during the first 30 days, after which it levelled off. However, calculated on the basis of applied C, the ADMSW was 10 times more degradable than the CMSW. Both MSW types caused initial net N immobilization followed by re-mineralization. A simple model based on the relationship between net N mineralization and respiration was only applicable for the MSW after significant modifications. If farmers are to recognize CMSW and ADMSW as valuable fertilizers, it is important that they can be produced with higher maturity, in order to avoid initial N immobilization. 相似文献
673.
Rochelle Constantine Debbie Steel Judy Allen Megan Anderson Olive Andrews C. Scott Baker Peta Beeman Daniel Burns Jean-Benoît Charrassin Simon Childerhouse Michael Double Paul Ensor Trish Franklin Wally Franklin Nick Gales Claire Garrigue Nadine Gibbs Peter Harrison Nan Hauser Amanda Hutsel Curt Jenner Micheline-Nicole Jenner Greg Kaufman Anne Macie David Mattila Carlos Olavarría Adrian Oosterman David Paton Michael Poole Jooke Robbins Natalie Schmitt Peter Stevick Alden Tagarino Kirsten Thompson Juney Ward 《Marine Biology》2014,161(5):1087-1093
Understanding the dynamics of population recovery is particularly complex when an organism has multiple, remote breeding and feeding grounds separated by one of the longest known migration routes. This study reports on the most comprehensive assessment of humpback whale (Megaptera novaeangliae) movements between remote Antarctic waters south of New Zealand and east Australia (EA), and the migratory corridors and breeding grounds of Australia and Oceania. A total of 112 individual whales were identified; 57 from microsatellites and 61 by fluke with 23 % (n = 26) matched to sites outside Antarctica. Despite large datasets from other southern regions being included in the comparison, the whales were predominantly linked to EA (n = 24). Only two matches to the Oceania catalogues directly north was surprising; therefore the primary feeding grounds of these endangered whales still remain unknown. The confirmation of the Balleny Islands as an important feeding ground for EA whales could provide an insight into reasons behind the rapid recovery of this population. Determining the feeding grounds of Oceania’s whales may explain whether prey energetics or migration length are limiting factors to their recovery and will allow an understanding of future ecosystem changes in these whales. 相似文献
674.
675.
Wesley M. Knapp Anne Frances Reed Noss Robert F. C. Naczi Alan Weakley George D. Gann Bruce G. Baldwin James Miller Patrick McIntyre Brent D. Mishler Gerry Moore Richard G. Olmstead Anna Strong Kathryn Kennedy Bonnie Heidel Daniel Gluesenkamp 《Conservation biology》2021,35(1):360-368
Extinction rates are expected to increase during the Anthropocene. Current extinction rates of plants and many animals remain unknown. We quantified extinctions among the vascular flora of the continental United States and Canada since European settlement. We compiled data on apparently extinct species by querying plant conservation databases, searching the literature, and vetting the resulting list with botanical experts. Because taxonomic opinion varies widely, we developed an index of taxonomic uncertainty (ITU). The ITU ranges from A to F, with A indicating unanimous taxonomic recognition and F indicating taxonomic recognition by only a single author. The ITU allowed us to rigorously evaluate extinction rates. Our data suggest that 51 species and 14 infraspecific taxa, representing 33 families and 49 genera of vascular plants, have become extinct in our study area since European settlement. Seven of these taxa exist in cultivation but are extinct in the wild. Most extinctions occurred in the west, but this outcome may reflect the timing of botanical exploration relative to settlement. Sixty-four percent of extinct plants were single-site endemics, and many occurred outside recognized biodiversity hotspots. Given the paucity of plant surveys in many areas, particularly prior to European settlement, the actual extinction rate of vascular plants is undoubtedly much higher than indicated here. 相似文献
676.
Pil Uthaug Rasmussen Katrine Uhrbrand Mette Damkj r Bartels Helle Neustrup Dorina Gabriela Karottki Ute B ltmann Anne Mette Madsen 《Frontiers of Environmental Science & Engineering》2021,15(3):41
677.
Karen A. Bjorndal Barbara A. Schroeder Allen M. Foley Blair E. Witherington Michael Bresette David Clark Richard M. Herren Michael D. Arendt Jeffrey R. Schmid Anne B. Meylan Peter A. Meylan Jane A. Provancha Kristen M. Hart Margaret M. Lamont Raymond R. Carthy Alan B. Bolten 《Marine Biology》2013,160(10):2711-2721
In response to a call from the US National Research Council for research programs to combine their data to improve sea turtle population assessments, we analyzed somatic growth data for Northwest Atlantic (NWA) loggerhead sea turtles (Caretta caretta) from 10 research programs. We assessed growth dynamics over wide ranges of geography (9–33°N latitude), time (1978–2012), and body size (35.4–103.3 cm carapace length). Generalized additive models revealed significant spatial and temporal variation in growth rates and a significant decline in growth rates with increasing body size. Growth was more rapid in waters south of the USA (<24°N) than in USA waters. Growth dynamics in southern waters in the NWA need more study because sample size was small. Within USA waters, the significant spatial effect in growth rates of immature loggerheads did not exhibit a consistent latitudinal trend. Growth rates declined significantly from 1997 through 2007 and then leveled off or increased. During this same interval, annual nest counts in Florida declined by 43 % (Witherington et al. in Ecol Appl 19:30–54, 2009) before rebounding. Whether these simultaneous declines reflect responses in productivity to a common environmental change should be explored to determine whether somatic growth rates can help interpret population trends based on annual counts of nests or nesting females. Because of the significant spatial and temporal variation in growth rates, population models of NWA loggerheads should avoid employing growth data from restricted spatial or temporal coverage to calculate demographic metrics such as age at sexual maturity. 相似文献
678.
Plant growth rates and seed size: a re-evaluation 总被引:1,自引:0,他引:1
Turnbull LA Philipson CD Purves DW Atkinson RL Cunniff J Goodenough A Hautier Y Houghton J Marthews TR Osborne CP Paul-Victor C Rose KE Saner P Taylor SH Woodward FI Hector A Rees M 《Ecology》2012,93(6):1283-1289
Small-seeded plant species are often reported to have high relative growth rate or RGR. However, because RGR declines as plants grow larger, small-seeded species could achieve higher RGR simply by virtue of their small size. In contrast, size-standardized growth rate or SGR factors out these size effects. Differences in SGR can thus only be due to differences in morphology, allocation, or physiology. We used nonlinear regression to calculate SGR for comparison with RGR for 10 groups of species spanning a wide range of life forms. We found that RGR was negatively correlated with seed mass in nearly all groups, but the relationship between SGR and seed mass was highly variable. We conclude that small-seeded species only sometimes possess additional adaptations for rapid growth over and above their general size advantage. 相似文献
679.
Tracking habitat and resource use for the jumbo squid Dosidicus gigas: a stable isotope analysis in the Northern Humboldt Current System 总被引:1,自引:0,他引:1
Juan Argüelles Anne Lorrain Yves Cherel Michelle Graco Ricardo Tafur Ana Alegre Pepe Espinoza Anatolio Taipe Patricia Ayón Arnaud Bertrand 《Marine Biology》2012,159(9):2105-2116
To determine the habitat and resource use of Dosidicus gigas in the Northern Humboldt Current System, we analysed carbon and nitrogen stable isotopes of 234 individuals collected during 2008–2010. Large variations in mantle stable isotope ratios were recorded, with values ranging from −19.1 to −15.1 ‰ (δ13C) and from 7.4 to 20.5 ‰ (δ15N). Most of the variation was explained by latitude, followed by distance to shelf break for carbon and by squid size for nitrogen. Latitudinal variations with increasing values from north to south were also found in zooplankton samples and were related to changes in isotope baseline values probably due to oxygen minimum zones that occur off Peru. This similar latitudinal trend in both zooplankton and D. gigas samples reveals that D. gigas is a relatively resident species at the scale of its isotopic turnover rate (i.e. a few weeks), even if this is not necessarily the case at the scale of its life. A small but significant size effect on δ13C values suggests that jumbo squid perform offshore–onshore ontogenic migration, with juveniles distributed offshore. For nitrogen, the high inter-individual variability observed with mantle length indicates that D. gigas can prey on a high variety of resources at any stage of their life cycle. This large-scale study off the coast of Peru provides further evidence that D. gigas have the capability to explore a wide range of habitats and resources at any stage of their life. 相似文献
680.
Stefan M. Klose Justin A. Welbergen Anne W. Goldizen Elisabeth K. V. Kalko 《Behavioral ecology and sociobiology》2009,63(3):371-380
The social structure of animal aggregations may vary considerably in both space and time, yet little is known about how this
affects vigilance. Here, we investigate the vigilance architecture of a colony of wild-living grey-headed flying-foxes (Pteropus poliocephalus) in Australia and examine how spatial as well as temporal variation in social organization influences social and environmental
vigilance. We sampled color-marked individuals at different stages of the reproductive cycle and the year and at different
locations in the colony to examine the effects of temporal and spatial factors on social and environmental vigilance. We found
that vigilance architecture reflected the social structure of the colony, with the highest environmental vigilance being displayed
by bats at the periphery of the colony, and the highest social vigilance by bats that roosted at intermediate distances from
the colony’s edge. Furthermore, we found that vigilance levels reflected changes in reproductive state, with social vigilance
increasing toward the mating season, particularly in males. Our findings show that spatial and temporal variation in social
structure can have differential effects on social and environmental vigilance. This highlights the necessity to differentiate
between functions of vigilance to understand fully vigilance architecture in aggregations of social animals. 相似文献