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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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Spectrum of the biogeographical affinities.of the species identified as indicators for the Atlantic, Alpine, Boreal, Continental, and Mediterraneo-Macaronesian regions resolved from the analysis of bryophyte species distributions in Europe.
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pone-0055648-g004: Spectrum of the biogeographical affinities.of the species identified as indicators for the Atlantic, Alpine, Boreal, Continental, and Mediterraneo-Macaronesian regions resolved from the analysis of bryophyte species distributions in Europe.

Mentions: The twenty species with the highest indicator value for each region (k = 6, 60% subsampling) are provided in Table 3. The regions where the species exhibit the highest indicator values are the Atlantic and Mediterranean (from 0.71 to 0.52 in the Atlantic and from 0.71 to 0.56 in the Mediterranean), whereas the region where the species exhibit the lowest indicator values is the marginal eastern region, where the 20 highest indicator values range between 0.11 and 0.05. The biogeographic spectrum of each of the Atlantic, Alpine, Boreal, Continental, and Mediterraneo-Macaronesian regions based on the biogeographic affinities of their indicator species is presented in Fig. 4. The affinities of the indicator species from the Atlantic, Alpine, Boreal regions are very homogeneous, whereas indicator species for the Mediterranean are of both Mediterranean and Mediterranean-oceanic affinities, and indicator species for the Continental region are very heterogeneous, including a mixture of continental, temperate, and boreal affinities.


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)

Spectrum of the biogeographical affinities.of the species identified as indicators for the Atlantic, Alpine, Boreal, Continental, and Mediterraneo-Macaronesian regions resolved from the analysis of bryophyte species distributions in Europe.
© Copyright Policy
Related In: Results  -  Collection

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

pone-0055648-g004: Spectrum of the biogeographical affinities.of the species identified as indicators for the Atlantic, Alpine, Boreal, Continental, and Mediterraneo-Macaronesian regions resolved from the analysis of bryophyte species distributions in Europe.
Mentions: The twenty species with the highest indicator value for each region (k = 6, 60% subsampling) are provided in Table 3. The regions where the species exhibit the highest indicator values are the Atlantic and Mediterranean (from 0.71 to 0.52 in the Atlantic and from 0.71 to 0.56 in the Mediterranean), whereas the region where the species exhibit the lowest indicator values is the marginal eastern region, where the 20 highest indicator values range between 0.11 and 0.05. The biogeographic spectrum of each of the Atlantic, Alpine, Boreal, Continental, and Mediterraneo-Macaronesian regions based on the biogeographic affinities of their indicator species is presented in Fig. 4. The affinities of the indicator species from the Atlantic, Alpine, Boreal regions are very homogeneous, whereas indicator species for the Mediterranean are of both Mediterranean and Mediterranean-oceanic affinities, and indicator species for the Continental region are very heterogeneous, including a mixture of continental, temperate, and boreal affinities.

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