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Margaret Byrne - One of the best experts on this subject based on the ideXlab platform.
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high species diversity and turnover in granite inselberg floras highlight the need for a conservation strategy protecting many outcrops
Ecology and Evolution, 2019Co-Authors: Colin J Yates, Stephen D Hopper, Todd Robinson, Grant Wardelljohnson, Gunnar Keppel, Antonius G.t. Schut, Margaret ByrneAbstract:: Determining patterns of plant diversity on granite inselbergs is an important task for conservation biogeography due to mounting threats. However, beyond the tropics there are relatively few quantitative studies of floristic diversity, or consideration of these patterns and their environmental, biogeographic, and historical correlates for conservation. We sought to contribute broader understanding of global patterns of species diversity on granite inselbergs and inform biodiversity conservation in the globally significant Southwest Australian Floristic Region (SWAFR). We surveyed Floristics from 16 inselbergs (478 plots) across the climate gradient of the SWAFR stratified into three major habitats on each outcrop. We recorded 1,060 species from 92 families. At the plot level, local soil and topographic variables affecting aridity were correlated with species richness in herbaceous (HO) and woody vegetation (WO) of soil-filled depressions, but not in woody vegetation on deeper soils at the base of outcrops (WOB). At the outcrop level, bioclimatic variables affecting aridity were correlated with species richness in two habitats (WO and WOB) but, contrary to predictions from island biogeography, were not correlated with inselberg area and isolation in any of the three habitats. Species turnover in each of the three habitats was also influenced by aridity, being correlated with bioclimatic variables and with interplot geographic distance, and for HO and WO habitats with local site variables. At the outcrop level, species replacement was the dominant component of species turnover in each of the three habitats, consistent with expectations for long-term stable landscapes. Our results therefore highlight high species diversity and turnover associated with granite outcrop flora. Hence, effective conservation strategies will need to focus on protecting multiple inselbergs across the entire climate gradient of the region.
Grant Wardelljohnson - One of the best experts on this subject based on the ideXlab platform.
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high species diversity and turnover in granite inselberg floras highlight the need for a conservation strategy protecting many outcrops
Ecology and Evolution, 2019Co-Authors: Colin J Yates, Stephen D Hopper, Todd Robinson, Grant Wardelljohnson, Gunnar Keppel, Antonius G.t. Schut, Margaret ByrneAbstract:: Determining patterns of plant diversity on granite inselbergs is an important task for conservation biogeography due to mounting threats. However, beyond the tropics there are relatively few quantitative studies of floristic diversity, or consideration of these patterns and their environmental, biogeographic, and historical correlates for conservation. We sought to contribute broader understanding of global patterns of species diversity on granite inselbergs and inform biodiversity conservation in the globally significant Southwest Australian Floristic Region (SWAFR). We surveyed Floristics from 16 inselbergs (478 plots) across the climate gradient of the SWAFR stratified into three major habitats on each outcrop. We recorded 1,060 species from 92 families. At the plot level, local soil and topographic variables affecting aridity were correlated with species richness in herbaceous (HO) and woody vegetation (WO) of soil-filled depressions, but not in woody vegetation on deeper soils at the base of outcrops (WOB). At the outcrop level, bioclimatic variables affecting aridity were correlated with species richness in two habitats (WO and WOB) but, contrary to predictions from island biogeography, were not correlated with inselberg area and isolation in any of the three habitats. Species turnover in each of the three habitats was also influenced by aridity, being correlated with bioclimatic variables and with interplot geographic distance, and for HO and WO habitats with local site variables. At the outcrop level, species replacement was the dominant component of species turnover in each of the three habitats, consistent with expectations for long-term stable landscapes. Our results therefore highlight high species diversity and turnover associated with granite outcrop flora. Hence, effective conservation strategies will need to focus on protecting multiple inselbergs across the entire climate gradient of the region.
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relating spatial and temporal patterns in Floristics with vegetation mapping an example from fraser island south east queensland australia
Pacific Conservation Biology, 2006Co-Authors: Ben E Lawson, Grant WardelljohnsonAbstract:The use of mapped polygons to represent vegetation patterns is becoming more widespread in conservation planning and natural resource management. The degree of homogeneity (i.e., one vegetation unit per polygon) of these polygons influences the efficacy of mapped patterns. It was observed that Fraser Island, south-east Queensland (SEQ) exhibited near complete map unit homogeneity relative to adjacent mainland areas. We sought to establish whether this homogeneity had an ecological or cartographic basis. Floristic presence-absence data from 50 quadrats, each sampled over three consecutive years, were analysed using cluster analysis (UPGMA) and ordination (SSH MDS) to define and compare eight numerically-derived plant community types with eight a priori regional ecosystem types derived from mapping of the island. Strong congruence between the two approaches was evident, suggesting that the mapping effectively portrayed ecological patterns. Floristic composition and species richness remained consistent at most quadrats for three consecutive years. Perennial woody species (including tree and shrub species) showed significant (P < 0.05) variation between regional ecosystem units and between plant community groups, but was stable through time. Conversely, the herb assemblage showed significant temporal variation and poor fidelity to vegetation classifications. High levels of map unit homogeneity were shown to extend to five barrier sand islands of SEQ across various map scales and map authors in these sandy environs. We conclude that homogeneity in mapped polygons on Fraser Island is a consequence of discrete boundaries and the associated distinctive Floristics of the vegetation communities in this area. We suggest focussing limited mapping resources to areas of high polygon heterogeneity, instead of areas such as the SEQ sand islands which appear well represented by existing mapping.
Gunnar Keppel - One of the best experts on this subject based on the ideXlab platform.
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high species diversity and turnover in granite inselberg floras highlight the need for a conservation strategy protecting many outcrops
Ecology and Evolution, 2019Co-Authors: Colin J Yates, Stephen D Hopper, Todd Robinson, Grant Wardelljohnson, Gunnar Keppel, Antonius G.t. Schut, Margaret ByrneAbstract:: Determining patterns of plant diversity on granite inselbergs is an important task for conservation biogeography due to mounting threats. However, beyond the tropics there are relatively few quantitative studies of floristic diversity, or consideration of these patterns and their environmental, biogeographic, and historical correlates for conservation. We sought to contribute broader understanding of global patterns of species diversity on granite inselbergs and inform biodiversity conservation in the globally significant Southwest Australian Floristic Region (SWAFR). We surveyed Floristics from 16 inselbergs (478 plots) across the climate gradient of the SWAFR stratified into three major habitats on each outcrop. We recorded 1,060 species from 92 families. At the plot level, local soil and topographic variables affecting aridity were correlated with species richness in herbaceous (HO) and woody vegetation (WO) of soil-filled depressions, but not in woody vegetation on deeper soils at the base of outcrops (WOB). At the outcrop level, bioclimatic variables affecting aridity were correlated with species richness in two habitats (WO and WOB) but, contrary to predictions from island biogeography, were not correlated with inselberg area and isolation in any of the three habitats. Species turnover in each of the three habitats was also influenced by aridity, being correlated with bioclimatic variables and with interplot geographic distance, and for HO and WO habitats with local site variables. At the outcrop level, species replacement was the dominant component of species turnover in each of the three habitats, consistent with expectations for long-term stable landscapes. Our results therefore highlight high species diversity and turnover associated with granite outcrop flora. Hence, effective conservation strategies will need to focus on protecting multiple inselbergs across the entire climate gradient of the region.
Colin J Yates - One of the best experts on this subject based on the ideXlab platform.
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high species diversity and turnover in granite inselberg floras highlight the need for a conservation strategy protecting many outcrops
Ecology and Evolution, 2019Co-Authors: Colin J Yates, Stephen D Hopper, Todd Robinson, Grant Wardelljohnson, Gunnar Keppel, Antonius G.t. Schut, Margaret ByrneAbstract:: Determining patterns of plant diversity on granite inselbergs is an important task for conservation biogeography due to mounting threats. However, beyond the tropics there are relatively few quantitative studies of floristic diversity, or consideration of these patterns and their environmental, biogeographic, and historical correlates for conservation. We sought to contribute broader understanding of global patterns of species diversity on granite inselbergs and inform biodiversity conservation in the globally significant Southwest Australian Floristic Region (SWAFR). We surveyed Floristics from 16 inselbergs (478 plots) across the climate gradient of the SWAFR stratified into three major habitats on each outcrop. We recorded 1,060 species from 92 families. At the plot level, local soil and topographic variables affecting aridity were correlated with species richness in herbaceous (HO) and woody vegetation (WO) of soil-filled depressions, but not in woody vegetation on deeper soils at the base of outcrops (WOB). At the outcrop level, bioclimatic variables affecting aridity were correlated with species richness in two habitats (WO and WOB) but, contrary to predictions from island biogeography, were not correlated with inselberg area and isolation in any of the three habitats. Species turnover in each of the three habitats was also influenced by aridity, being correlated with bioclimatic variables and with interplot geographic distance, and for HO and WO habitats with local site variables. At the outcrop level, species replacement was the dominant component of species turnover in each of the three habitats, consistent with expectations for long-term stable landscapes. Our results therefore highlight high species diversity and turnover associated with granite outcrop flora. Hence, effective conservation strategies will need to focus on protecting multiple inselbergs across the entire climate gradient of the region.
Fayolle Adeline - One of the best experts on this subject based on the ideXlab platform.
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A sharp floristic discontinuity revealed by the biogeographic regionalization of African savannas
'Wiley', 2019Co-Authors: Fayolle Adeline, Swaine, Michael D., Aleman Julie, Azihou, Akomian F., Bauman David, Te Beest Mariska, Chidumayo, Emmanuel N., Cromsigt, Joris P. G. M., Dessard Hélène, Finckh ManfredAbstract:peer reviewedaudience: researcher, professional, studentAim: In tropical Africa, savannas cover huge areas, have high plant species richness and are considered as a major natural resource for most countries. There is, however, little information available on their Floristics and biogeography at the continental scale, despite the importance of such information for our understanding of the drivers of species diversity at various scales and for effective conservation and management. Here, we collated and analysed floristic data from across the continent in order to propose a biogeographical regionalization for African savannas. Location: We collated floristic information (specifically woody species lists) for 298 samples of savanna vegetation across Africa, extending from 18° N to 33° S and from 17° W to 48° E. Taxa: We focused on native woody species. Methods: We used ordination and clustering to identify the floristic discontinuities and gradual transitions across African savannas. Floristic relationships, specificity and turnover, within and between floristic clusters, were analysed using a (dis‐)similarity‐ based approach. Results: We identified eight floristic clusters across African savannas which in turn were grouped into two larger macro‐units. Ordinations at species and genus levels showed a clear differentiation in woody species composition between the North/ West macro‐unit and the South/East macro‐unit. This floristic discontinuity matches to the High (i.e. N&W) and Low (S&E) division of Africa previously proposed by White (1983) and which tracks climatic and topographical variation. In the N&W savannas, the floristic gradient determined by rainfall was partitioned into the Sudanian (drier) and Guinean (wetter) clusters. Within the highly heterogeneous S&E savannas and woodlands, six clusters were identified: Ugandan, Ethiopian, Mozambican, Zambezian, Namibian and South African. Main conclusions: The proposed pan‐African classification of savannas and woodlands might assist the development of coordinated management and conservation policies
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A sharp floristic discontinuity revealed by the biogeographic regionalization of African savannas [presence data]
2019Co-Authors: Fayolle AdelineAbstract:audience: researcherAim. In tropical Africa, savannas cover huge areas, have high plant species richness, and are considered as a major natural resource for most countries. There is, however, little information available on their Floristics and biogeography at the continental scale, despite the importance of such information for our understanding of the drivers of species diversity at various scales and for effective conservation and management. Here, we collated and analysed floristic data from across the continent in order to propose a biogeographic regionalization for African savannas. Location. We collated floristic information (specifically woody species lists) for 298 samples of savanna vegetation across Africa, extending from 18°N to 33°S and from 17°W to 48°E. Taxon. We focused on native woody species. Methods. We used ordination and clustering to identify the floristic discontinuities and gradual transitions across African savannas. Floristic relationships, specificity and turnover, within and between floristic clusters, were analysed using a (dis-)similarity-based approach. Results. We identified eight floristic clusters across African savannas which in turn were grouped into two larger macro-units. Ordinations at species and genus levels showed a clear differentiation in woody species composition between the North/West macro-unit and the South/East macro-unit. This floristic discontinuity matches to the High (i.e., N&W) and Low (S&E) division of Africa previously proposed by White (1983) and which tracks climatic and topographic variation. In the N&W savannas, the floristic gradient determined by rainfall was partitioned into the Sudanian (drier) and Guinean (wetter) clusters. Within the highly heterogeneous S&E savannas and woodlands, six clusters were identified: Ugandan, Ethiopian, Mozambican, Zambezian, Namibian and South-African. Main conclusions. The proposed pan-African classification of savannas and woodlands might assist the development of coordinated management and conservation policies.Presence data of woody species across African savanna sites analysed in the paper entitled 'A sharp floristic discontinuity revealed by the biogeographic regionalization of African savannas' published in Journal of Biogeography by Adeline Fayolle, Michael D. Swaine, Julie Aleman, Akomian F. Azihou, David Bauman, Mariska te Beest, Emmanuel N. Chidumayo, Joris P.G.M. Cromsigt, Hélène Dessard, Manfred Finckh, Francisco Maiato P. Gonçalves, Jean-Francois Gillet, Anais Gorel, Aurélie Hick, Ricardo Holdo, Ben Kirunda, Gregory Mahy, Iain McNicol, Casey M Ryan, Rasmus Revermann, Andrew Plumptre, Rose Pritchard, Paula Nieto-Quintano, Christine B. Schmitt, Josiane Seghieri, Tony Swemmer, Habte Talila and Emily Woollen
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A sharp floristic discontinuity revealed by the biogeographic regionalization of African savannas [presence data]
2018Co-Authors: Fayolle AdelineAbstract:Aim. In tropical Africa, savannas cover huge areas, have high plant species richness, and are considered as a major natural resource for most countries. There is, however, little information available on their Floristics and biogeography at the continental scale, despite the importance of such information for our understanding of the drivers of species diversity at various scales and for effective conservation and management. Here, we collated and analysed floristic data from across the continent in order to propose a biogeographic regionalization for African savannas. Location. We collated floristic information (specifically woody species lists) for 298 samples of savanna vegetation across Africa, extending from 18°N to 33°S and from 17°W to 48°E. Taxon. We focused on native woody species. Methods. We used ordination and clustering to identify the floristic discontinuities and gradual transitions across African savannas. Floristic relationships, specificity and turnover, within and between floristic clusters, were analysed using a (dis-)similarity-based approach. Results. We identified eight floristic clusters across African savannas which in turn were grouped into two larger macro-units. Ordinations at species and genus levels showed a clear differentiation in woody species composition between the North/West macro-unit and the South/East macro-unit. This floristic discontinuity matches to the High (i.e., N&W) and Low (S&E) division of Africa previously proposed by White (1983) and which tracks climatic and topographic variation. In the N&W savannas, the floristic gradient determined by rainfall was partitioned into the Sudanian (drier) and Guinean (wetter) clusters. Within the highly heterogeneous S&E savannas and woodlands, six clusters were identified: Ugandan, Ethiopian, Mozambican, Zambezian, Namibian and South-African. Main conclusions. The proposed pan-African classification of savannas and woodlands might assist the development of coordinated management and conservation policies
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A sharp floristic discontinuity revealed by the biogeographic regionalization of African savannas
2018Co-Authors: Fayolle Adeline, Swaine, Michael D., Aleman Julie, Azihou, Akomian F., Bauman David, Te Beest Mariska, Chidumayo, Emmanuel N., Cromsigt, Joris P. G. M., Dessard Hélène, Finckh ManfredAbstract:Aim: In tropical Africa, savannas cover huge areas, have high plant species richness and are considered as a major natural resource for most countries. There is, however, little information available on their Floristics and biogeography at the continental scale, despite the importance of such information for our understanding of the drivers of species diversity at various scales and for effective conservation and management. Here, we collated and analysed floristic data from across the continent in order to propose a biogeographical regionalization for African savannas. Location: We collated floristic information (specifically woody species lists) for 298 samples of savanna vegetation across Africa, extending from 18° N to 33° S and from 17° W to 48° E. Taxa: We focused on native woody species. Methods: We used ordination and clustering to identify the floristic discontinuities and gradual transitions across African savannas. Floristic relationships, specificity and turnover, within and between floristic clusters, were analysed using a (dis‐)similarity‐ based approach. Results: We identified eight floristic clusters across African savannas which in turn were grouped into two larger macro‐units. Ordinations at species and genus levels showed a clear differentiation in woody species composition between the North/ West macro‐unit and the South/East macro‐unit. This floristic discontinuity matches to the High (i.e. N&W) and Low (S&E) division of Africa previously proposed by White (1983) and which tracks climatic and topographical variation. In the N&W savannas, the floristic gradient determined by rainfall was partitioned into the Sudanian (drier) and Guinean (wetter) clusters. Within the highly heterogeneous S&E savannas and woodlands, six clusters were identified: Ugandan, Ethiopian, Mozambican, Zambezian, Namibian and South African. Main conclusions: The proposed pan‐African classification of savannas and woodlands might assist the development of coordinated management and conservation policies.Peer reviewe
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Woody species composition of African savannas and dry forests
2017Co-Authors: Fayolle Adeline, Swaine, Michael D., Azihou Fortuné, Chidumayo Emmanuel, Hick Aurélie, Plumptre AndrewAbstract:Background Though savannas dominate the terrestrial tropics, harvest a substantial species diversity and are considered as a major resource for developing countries, there is however little information available on their Floristics and biogeography, specifically in Africa. Aim In this study we aimed to identify large-scale variation in woody species composition across tropical African savannas and dry forests, and determined the underlying environmental and historical factors. Methods We report multivariate analysis of more than 200 samples describing the woody species composition of savanna vegetation across Africa. The samples extend from 18° N to 26° S and from 17° W to 48° E including 30 countries. The data were collated from published books and papers, the authors’ personal data and a few websites. Main results Correspondence analysis showed a clear differentiation in woody species composition in the north and west (Sudanian Region) from those in the east and south (Zambezian Region). The floristic transition between the two groups was in north eastern Africa (Uganda, Kenya, Ethiopia and Somalia) where the barrier of the equatorial forest zone does not intervene. Within each group, there was a strong floristic gradient related to annual rainfall. Conclusion We examined the relationship between environment (climate, altitude, geology, soils) and the floristic groups to highlight possible determining influences. We propose a pan-African classification that might assist in the development of management and conservation policies