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71.
Accelerating Possession: Global Future of Property and Personhood . Bill Maurer and Gabrielle Schwab, eds. New York: Columbia University Press, 2006. 275 pp. 相似文献
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RYAN M. HUEBINGER THOMAS W. J. DE MAAR LAURENCE H. WOODRUFF DANIEL POMP EDWARD E. LOUIS 《Molecular ecology resources》2006,6(4):1150-1151
Eight microsatellite loci were isolated from a genomic DNA library created from Grant's gazelle (Gazella granti). Observed and expected levels of heterozygosity were computed utilizing 20 individuals from a population in Central Kenya. Tests for Hardy–Weinberg equilibria were conducted and found that two of the eight loci deviated from equilibrium in this population. These markers were developed to analyse the genetic effects of culling and isolation on a game preserve in Kenya. 相似文献
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CLIVE A. MCALPINE MICHIALA E. BOWEN JOHN G. CALLAGHAN DANIEL LUNNEY JONATHAN R. RHODES DAVID L. MITCHELL DAVID V. PULLAR HUGH P. POSZINGHAM 《Austral ecology》2006,31(4):529-544
Abstract Predicting the various responses of different species to changes in landscape structure is a formidable challenge to landscape ecology. Based on expert knowledge and landscape ecological theory, we develop five competing a priori models for predicting the presence/absence of the Koala (Phascolarctos cinereus) in Noosa Shire, south‐east Queensland (Australia). A priori predictions were nested within three levels of ecological organization: in situ (site level) habitat (<1 ha), patch level (100 ha) and landscape level (100–1000 ha). To test the models, Koala surveys and habitat surveys (n = 245) were conducted across the habitat mosaic. After taking into account tree species preferences, the patch and landscape context, and the neighbourhood effect of adjacent present sites, we applied logistic regression and hierarchical partitioning analyses to rank the alternative models and the explanatory variables. The strongest support was for a multilevel model, with Koala presence best predicted by the proportion of the landscape occupied by high quality habitat, the neighbourhood effect, the mean nearest neighbour distance between forest patches, the density of forest patches and the density of sealed roads. When tested against independent data (n = 105) using a receiver operator characteristic curve, the multilevel model performed moderately well. The study is consistent with recent assertions that habitat loss is the major driver of population decline, however, landscape configuration and roads have an important effect that needs to be incorporated into Koala conservation strategies. 相似文献
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Assessment of European streams with diatoms, macrophytes, macroinvertebrates and fish: a comparative metric-based analysis of organism response to stress 总被引:10,自引:0,他引:10
DANIEL HERING RICHARD K. JOHNSON SANDRA KRAMM STEFAN SCHMUTZ KRZYSZTOF SZOSZKIEWICZ PIET F. M. VERDONSCHOT 《Freshwater Biology》2006,51(9):1757-1785
1. Periphytic diatoms, macrophytes, benthic macroinvertebrates and fish were sampled with standard methods in 185 streams in nine European countries to compare their response to degradation. Streams were classified into two main stream type groups (i.e. lowland, mountain streams); in addition, the lowland streams were grouped into four more specific stream types. 2. Principal components analysis with altogether 43 environmental parameters was used to construct complex stressor gradients for physical–chemical, hydromorphological and land use data. About 30 metrics were calculated for each sample and organism group. Metric responses to different stress types were analysed by Spearman Rank Correlation. 3. All four organism groups showed significant response to eutrophication/organic pollution gradients. Generally, diatom metrics were most strongly correlated to eutrophication gradients (85% and 89% of the diatom metrics tested correlated significantly in mountain and lowland streams, respectively), followed by invertebrate metrics (91% and 59%). 4. Responses of the four organism groups to other gradients were less strong; all organism groups responded to varying degrees to land use changes, hydromorphological degradation on the microhabitat scale and general degradation gradients, while the response to hydromorphological gradients on the reach scale was mainly limited to benthic macroinvertebrates (50% and 44% of the metrics tested correlated significantly in mountain and lowland streams, respectively) and fish (29% and 47%). 5. Fish and macrophyte metrics generally showed a poor response to degradation gradients in mountain streams and a strong response in lowland streams. 6. General recommendations on European bioassessment of streams were derived from the results. 相似文献
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Butterfly,seedling, sapling and tree diversity and composition in a fire‐affected Bornean rainforest
DANIEL F. R. CLEARY ALDRIANTO PRIADJATI BAMBANG K. SURYOKUSUMO STEPH B. J. MENKEN 《Austral ecology》2006,31(1):46-57
Abstract: Fire‐affected forests are becoming an increasingly important component of tropical landscapes. The impact of wildfires on rainforest communities is, however, poorly understood. In this study the density, species richness and community composition of seedlings, saplings, trees and butterflies were assessed in unburned and burned forest following the 1997/98 El Niño Southern Oscillation burn event in East Kalimantan, Indonesia. More than half a year after the fires, sapling and tree densities in the burned forest were only 2.5% and 38.8%, respectively, of those in adjacent unburned forest. Rarefied species richness and Shannon's H’ were higher in unburned forest than burned forest for all groups but only significantly so for seedlings. There were no significant differences in evenness between unburned and burned forest. Matrix regression and Akaike's information criterion (AIC) revealed that the best explanatory models of similarity included both burning and the distance between sample plots indicating that both deterministic processes (related to burning) and dispersal driven stochastic processes structure post‐disturbance rainforest assemblages. Burning though explained substantially more variation in seedling assemblage structure whereas distance was a more important explanatory variable for trees and butterflies. The results indicate that butterfly assemblages in burned forest were primarily derived from adjacent unburned rainforest, exceptions being species of grass‐feeders such as Orsotriaena medus that are normally found in open, disturbed areas, whereas burned forest seedling assemblages were dominated by typical pioneer genera, such as various Macaranga species that were absent or rare in unburned forest. Tree assemblages in the burned forest were represented by a subset of fire‐resistant species, such as Eusideroxylon zwageri and remnant dominant species from the unburned forest. 相似文献
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