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Modeling species distributions from heterogeneous data for the biogeographic regionalization of the European bryophyte flora.

Mateo RG, Vanderpoorten A, Muñoz J, Laenen B, Désamoré A - PLoS ONE (2013)

Bottom Line: Previous research suggested that environmental forcing results in highly congruent regionalization patterns across taxa, but that the size and number of regions depends on the dispersal ability of the taxa considered.The substantially lower optimal number of clusters and the absence of nested patterns within the main biogeographic regions, as compared to identical analyses in vascular plants, support our second hypothesis.The modelling approach implemented here is, however, based on many assumptions that are discussed but can only be tested when additional data on species distributions become available, highlighting the substantial importance of developing integrated mapping projects for all taxa in key biogeographically areas of Europe, and the Mediterranean peninsulas in particular.

View Article: PubMed Central - PubMed

Affiliation: Institute of Botany, University of Liège, Liège, Belgium. rubeng.mateo@gmail.com

ABSTRACT
The definition of biogeographic regions provides a fundamental framework for a range of basic and applied questions in biogeography, evolutionary biology, systematics and conservation. Previous research suggested that environmental forcing results in highly congruent regionalization patterns across taxa, but that the size and number of regions depends on the dispersal ability of the taxa considered. We produced a biogeographic regionalization of European bryophytes and hypothesized that (1) regions defined for bryophytes would differ from those defined for other taxa due to the highly specific eco-physiology of the group and (2) their high dispersal ability would result in the resolution of few, large regions. Species distributions were recorded using 10,000 km2 MGRS pixels. Because of the lack of data across large portions of the area, species distribution models employing macroclimatic variables as predictors were used to determine the potential composition of empty pixels. K-means clustering analyses of the pixels based on their potential species composition were employed to define biogeographic regions. The optimal number of regions was determined by v-fold cross-validation and Moran's I statistic. The spatial congruence of the regions identified from their potential bryophyte assemblages with large-scale vegetation patterns is at odds with our primary hypothesis. This reinforces the notion that post-glacial migration patterns might have been much more similar in bryophytes and vascular plants than previously thought. The substantially lower optimal number of clusters and the absence of nested patterns within the main biogeographic regions, as compared to identical analyses in vascular plants, support our second hypothesis. The modelling approach implemented here is, however, based on many assumptions that are discussed but can only be tested when additional data on species distributions become available, highlighting the substantial importance of developing integrated mapping projects for all taxa in key biogeographically areas of Europe, and the Mediterranean peninsulas in particular.

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Biogeographical regions of Europe.(http://www.eea.europa.eu/data-and-maps/data/biogeographical-regions-europe-2008) resulting from the ‘Map of Natural Vegetation of the member countries of the European Community and of the Council of Europe’ (Bohn et al., 2000-2004) rescaled at the resolution level of the MGRS pixels.
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pone-0055648-g002: Biogeographical regions of Europe.(http://www.eea.europa.eu/data-and-maps/data/biogeographical-regions-europe-2008) resulting from the ‘Map of Natural Vegetation of the member countries of the European Community and of the Council of Europe’ (Bohn et al., 2000-2004) rescaled at the resolution level of the MGRS pixels.

Mentions: The biogeographic regionalization selected was compared to the biogeographical regions of Europe (http://www.eea.europa.eu/data-and-maps/data/biogeographical-regions-europe-2008) resulting from the ‘Map of Natural Vegetation of the member countries of the European Community and of the Council of Europe’ [41] (Fig. 2). The similarity of the clusters was assessed by computing the percent of MGRS pixels assigned to one region based upon the bryophyte analyses and to the same region defined by Bohn et al. [41]. This overlap does, however, not take into account the percent of MGRS pixels assigned to one region by Bohn et al. [41] and to the same region as defined by the bryophyte analyses. We therefore employed a second measure of congruence between the two classifications, namely the kappa statistics [42]. Kappa values were computed with Map Comparison Kit 3.0 (Netherlands Environmental Assessment Agency, http://www.riks.nl/mck/). Following Metzger et al. [43], a Kappa value of less than 0.2 represents very poor agreement, 0.2–0.4 poor, 0.4–0.55 fair, 0.55–0.7 good, 0.7–0.85 very good, and greater than 0.85 excellent agreement.


Modeling species distributions from heterogeneous data for the biogeographic regionalization of the European bryophyte flora.

Mateo RG, Vanderpoorten A, Muñoz J, Laenen B, Désamoré A - PLoS ONE (2013)

Biogeographical regions of Europe.(http://www.eea.europa.eu/data-and-maps/data/biogeographical-regions-europe-2008) resulting from the ‘Map of Natural Vegetation of the member countries of the European Community and of the Council of Europe’ (Bohn et al., 2000-2004) rescaled at the resolution level of the MGRS pixels.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3569459&req=5

pone-0055648-g002: Biogeographical regions of Europe.(http://www.eea.europa.eu/data-and-maps/data/biogeographical-regions-europe-2008) resulting from the ‘Map of Natural Vegetation of the member countries of the European Community and of the Council of Europe’ (Bohn et al., 2000-2004) rescaled at the resolution level of the MGRS pixels.
Mentions: The biogeographic regionalization selected was compared to the biogeographical regions of Europe (http://www.eea.europa.eu/data-and-maps/data/biogeographical-regions-europe-2008) resulting from the ‘Map of Natural Vegetation of the member countries of the European Community and of the Council of Europe’ [41] (Fig. 2). The similarity of the clusters was assessed by computing the percent of MGRS pixels assigned to one region based upon the bryophyte analyses and to the same region defined by Bohn et al. [41]. This overlap does, however, not take into account the percent of MGRS pixels assigned to one region by Bohn et al. [41] and to the same region as defined by the bryophyte analyses. We therefore employed a second measure of congruence between the two classifications, namely the kappa statistics [42]. Kappa values were computed with Map Comparison Kit 3.0 (Netherlands Environmental Assessment Agency, http://www.riks.nl/mck/). Following Metzger et al. [43], a Kappa value of less than 0.2 represents very poor agreement, 0.2–0.4 poor, 0.4–0.55 fair, 0.55–0.7 good, 0.7–0.85 very good, and greater than 0.85 excellent agreement.

Bottom Line: Previous research suggested that environmental forcing results in highly congruent regionalization patterns across taxa, but that the size and number of regions depends on the dispersal ability of the taxa considered.The substantially lower optimal number of clusters and the absence of nested patterns within the main biogeographic regions, as compared to identical analyses in vascular plants, support our second hypothesis.The modelling approach implemented here is, however, based on many assumptions that are discussed but can only be tested when additional data on species distributions become available, highlighting the substantial importance of developing integrated mapping projects for all taxa in key biogeographically areas of Europe, and the Mediterranean peninsulas in particular.

View Article: PubMed Central - PubMed

Affiliation: Institute of Botany, University of Liège, Liège, Belgium. rubeng.mateo@gmail.com

ABSTRACT
The definition of biogeographic regions provides a fundamental framework for a range of basic and applied questions in biogeography, evolutionary biology, systematics and conservation. Previous research suggested that environmental forcing results in highly congruent regionalization patterns across taxa, but that the size and number of regions depends on the dispersal ability of the taxa considered. We produced a biogeographic regionalization of European bryophytes and hypothesized that (1) regions defined for bryophytes would differ from those defined for other taxa due to the highly specific eco-physiology of the group and (2) their high dispersal ability would result in the resolution of few, large regions. Species distributions were recorded using 10,000 km2 MGRS pixels. Because of the lack of data across large portions of the area, species distribution models employing macroclimatic variables as predictors were used to determine the potential composition of empty pixels. K-means clustering analyses of the pixels based on their potential species composition were employed to define biogeographic regions. The optimal number of regions was determined by v-fold cross-validation and Moran's I statistic. The spatial congruence of the regions identified from their potential bryophyte assemblages with large-scale vegetation patterns is at odds with our primary hypothesis. This reinforces the notion that post-glacial migration patterns might have been much more similar in bryophytes and vascular plants than previously thought. The substantially lower optimal number of clusters and the absence of nested patterns within the main biogeographic regions, as compared to identical analyses in vascular plants, support our second hypothesis. The modelling approach implemented here is, however, based on many assumptions that are discussed but can only be tested when additional data on species distributions become available, highlighting the substantial importance of developing integrated mapping projects for all taxa in key biogeographically areas of Europe, and the Mediterranean peninsulas in particular.

Show MeSH
Related in: MedlinePlus