Literaturdatenbank |
Segurado, P. (2007). Occurrence and persistence of freshwater turtles in portugal: Problems of scale and implications for conservation. Unpublished thesis , Universidae de Évora, Évora.
Added by: Sarina Wunderlich (06 Jul 2014 16:17:20 UTC) |
Resource type: Thesis/Dissertation BibTeX citation key: anon2007.16476 View all bibliographic details |
Categories: General Keywords: Habitat - habitat, Schildkröten - turtles + tortoises, Südwesteuropa - South-Western Europa, Testudinidae, Testudo marginata Creators: Segurado Publisher: Universidae de Évora (Évora) |
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Abstract |
Correlative modelling approaches have been used as first approximations to infer the role of environmental and biotic factors underlying species occurrences. However correlative models cannot demonstrate unequivocally causal relationships. Furthermore a number of artefacts may cause some inferred relationships to be spurious. In this thesis I focus my work on these sources of uncertainty. First I demonstrate the joint effect of the kind of modelling technique and species macroecological traits in the accuracy of models of species distribution. Then, by means of simulated spatial patterns I assess the overestimation of species distribution models’ accuracy due to spatial autocorrelation. Third, I address the issue of the effect of spatial scale on patterns of species co-occurrence showing that evidences of spatial segregation at finer scales can be inversed at wider scales. In the last part I propose a simple resampling technique to overcome problems derived from sampling artefacts due to species rarity. Emys orbicularis Mauremys leprosa
Added by: Sarina Wunderlich |