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91.
Lorraine H. L. Gormley Peter A. Furley Allan D. Watt 《Journal of Insect Conservation》2007,11(2):131-139
The conservation of biodiversity is increasingly dependent on human-altered habitats. In a fragmented forest landscape in
northern Costa Rica within the Mesoamerican Biological Corridor, an area of great conservation importance, we compared the
diversity and composition of ground-dwelling beetle communities in five habitat types along a gradient of increasing disturbance:
primary forest, logged forest, secondary forest, plantation (Gmelina arborea) and pasture. Using pitfall trapping we captured a total of 1,877 beetles (Coleoptera), comprising 422 morphospecies in 26
families. The plantation sites had the lowest number of species followed by secondary forest and pasture. Multivariate analysis
separated the beetle fauna according to land use, and suggested that only the logged forest maintains a similar species assemblage
to primary forest. However, each habitat harboured a number of unique species indicating the conservation value of the mosaic
of habitats found in fragmented landscapes. Our results suggest that to maintain forest beetle species diversity it is essential
that areas of natural forest are conserved. However, other land uses also provide beetle habitats and in fragmented areas
active management to maintain a mosaic of land uses will contribute to the conservation of beetle diversity. 相似文献
92.
Many studies of contingency judgments have used a task in which, on each trial, the participant is free either to respond or not to respond, and an outcome may, or may not, be presented. Typically, the experimenter specifies a nominal value for the contingency between responding and outcome, but the actual values of a variety of variables experienced by a particular participant depend on that participant's frequency of responding. The results of computer simulations of various strategies for implementing the contingency manipulation, and the results of an experiment, indicate that the same nominal contingency value will lead to considerable variability in the actual contingency experienced by participants. Moreover, nominal contingency manipulations are confounded with the probability that the subject experiences an outcome. While researchers might be aware of these issues, not enough attention has been paid to their potential impact. 相似文献
93.
Background
Brucella species include economically important zoonotic pathogens that can infect a wide range of animals. There are currently six classically recognised species of Brucella although, as yet unnamed, isolates from various marine mammal species have been reported. In order to investigate genetic relationships within the group and identify potential diagnostic markers we have sequenced multiple genetic loci from a large sample of Brucella isolates representing the known diversity of the genus. 相似文献94.
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Projecting future expansion of invasive species: comparing and improving methodologies for species distribution modeling 下载免费PDF全文
Kumar P. Mainali Dan L. Warren Kunjithapatham Dhileepan Andrew McConnachie Lorraine Strathie Gul Hassan Debendra Karki Bharat B. Shrestha Camille Parmesan 《Global Change Biology》2015,21(12):4464-4480
Modeling the distributions of species, especially of invasive species in non‐native ranges, involves multiple challenges. Here, we developed some novel approaches to species distribution modeling aimed at reducing the influences of such challenges and improving the realism of projections. We estimated species–environment relationships for Parthenium hysterophorus L. (Asteraceae) with four modeling methods run with multiple scenarios of (i) sources of occurrences and geographically isolated background ranges for absences, (ii) approaches to drawing background (absence) points, and (iii) alternate sets of predictor variables. We further tested various quantitative metrics of model evaluation against biological insight. Model projections were very sensitive to the choice of training dataset. Model accuracy was much improved using a global dataset for model training, rather than restricting data input to the species’ native range. AUC score was a poor metric for model evaluation and, if used alone, was not a useful criterion for assessing model performance. Projections away from the sampled space (i.e., into areas of potential future invasion) were very different depending on the modeling methods used, raising questions about the reliability of ensemble projections. Generalized linear models gave very unrealistic projections far away from the training region. Models that efficiently fit the dominant pattern, but exclude highly local patterns in the dataset and capture interactions as they appear in data (e.g., boosted regression trees), improved generalization of the models. Biological knowledge of the species and its distribution was important in refining choices about the best set of projections. A post hoc test conducted on a new Parthenium dataset from Nepal validated excellent predictive performance of our ‘best’ model. We showed that vast stretches of currently uninvaded geographic areas on multiple continents harbor highly suitable habitats for parthenium. However, discrepancies between model predictions and parthenium invasion in Australia indicate successful management for this globally significant weed. 相似文献
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Development of a high-density cranberry SSR linkage map for comparative genetic analysis and trait detection 总被引:2,自引:0,他引:2
Brandon Schlautman Giovanny Covarrubias-Pazaran Luis A. Diaz-Garcia Jennifer Johnson-Cicalese Massimo Iorrizo Lorraine Rodriguez-Bonilla Tierney Bougie Tiffany Bougie Eric Wiesman Shawn Steffan James Polashock Nicholi Vorsa Juan Zalapa 《Molecular breeding : new strategies in plant improvement》2015,35(8):1-18
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