The Experts below are selected from a list of 123 Experts worldwide ranked by ideXlab platform
Simonetta Bagella - One of the best experts on this subject based on the ideXlab platform.
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Mediterranean cork oak Wooded Grasslands: synergies and trade-offs between plant diversity, pasture production and soil carbon
Agroforestry Systems, 2018Co-Authors: Giovanna Seddaiu, L. Salis, Simonetta Bagella, Antonio Pulina, Chiara Cappai, Ivo Rossetti, Roberto Lai, Pier Paolo RoggeroAbstract:Mediterranean Wooded Grasslands that emerge from silvopastoral activities are multifunctional systems that result in high biodiversity and offer ecosystem services such as forage production and soil carbon sequestration. During 3 years, ten grazed Wooded grassland fields were studied in the Berchidda–Monti long-term observatory, located in NE Sardinia, Italy, with the aim of exploring the synergies and trade-offs between biodiversity and selected ecosystem services. Positions below and outside the canopy of three cork oak trees in each field were randomly selected to compare seasonal pasture production, pasture utilization rate by animals, botanical composition, biodiversity indicators (Shannon index and plant species richness) and soil organic carbon. In autumn, dry matter production of pasture was similar in the two positions; in two winters out of three it was greater below the trees than outside, and in spring it was greater outside than below the trees. While plant species richness and Shannon index were not significantly influenced by the position, the overall Wooded grassland plant species richness was 31% higher than that outside of the tree crown. The soil organic carbon content in the 0–40-cm soil layer was also higher below the trees. Our findings highlight that if the main purpose of the Wooded Grasslands is to provide forage for grazing animals rather than conserving and/or enhancing plant diversity and soil fertility, the presence of trees constrains the overall forage productivity, although the greater forage availability in winter under the trees can contribute to improve the seasonal distribution of forage production.
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Isolated cork oak trees affect soil properties and biodiversity in a Mediterranean Wooded grassland
Agriculture Ecosystems & Environment, 2015Co-Authors: Ivo Rossetti, Simonetta Bagella, Chiara Cappai, Pier Paolo Roggero, Maria Carmela Caria, P. Martins Da Silva, José Paulo Sousa, Pascal Querner, Giovanna SeddaiuAbstract:Abstract Mediterranean Wooded Grasslands are multipurpose systems that support high plant and animal diversity levels and are habitats of European importance (i.e., 6310 – Dehesas with evergreen Quercus spp.). Moreover, these systems offer a number of agro-ecosystem services such as forage production, soil carbon sequestration, nutrient recycling and soil protection. The scattered trees enhance the ecological complexity of grassland influencing the soil properties, the herbaceous layer diversity and composition and the soil communities. Understanding how isolated trees influence the other components of the system is essential to comprehend their role supporting high levels of above and below ground biodiversity and ecosystem services. In the present study, we present a hypothetical framework of the effects of isolated trees on soil properties, plant and soil fauna assemblages, the latter here represented by the class Collembola. The floor litter and the associated input of organic matter to the soil was a key factor linking the components of the tree-soil-biodiversity system in a Mediterranean cork oak Wooded grassland. Topsoil C increased by +50% under the tree canopy in comparison with the areas beyond the tree canopy. Plant diversity was lower under tree canopy, but contributed to enhance the total species richness of the grassland. Collembolan diversity was higher under the peculiar conditions beneath the tree canopy. Relationships between plant and collembolan species emerged. The findings of this study suggest that isolated trees have direct and indirect effects on soil properties, plant and collembolan assemblages, hence they can influence the ecological processes of Wooded Grasslands, with implications for food webs, nutrient cycling and productivity of the agro-ecosystem.
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mediterranean quercus suber Wooded Grasslands risk disappearance new evidences from sardinia italy
Forest Ecology and Management, 2014Co-Authors: Ivo Rossetti, Simonetta BagellaAbstract:Wooded Grasslands are the most widespread agro-forestry systems in Europe, and are included in the Natura 2000 network due to their importance in biodiversity conservation. Similar to many man-made systems, long-term Wooded Grasslands conservation depends on sustainable use practices. Regeneration of the tree layer is indispensable to assure Wooded grassland maintenance. Several studies in Spanish dehesas and Portuguese montados generated concerns regarding the long-term conservation of these agro-silvo-pastoral systems. In the present study, we tested if tree regeneration issues documented for the Iberian Peninsula also affected Wooded Grasslands located in another Mediterranean area inside and outside Natura 2000 network. The size structure of Quercus suber L. stands, and the abundance and height of seedlings and saplings were determined at farm and landscape scales, in grazed, grazed and tilled Wooded Grasslands, and non-grazed woodlands to test the compatibility of management type for tree regeneration. A frequency model of size structure was calculated to estimate the probability of cork oak stand survival in a medium and long term time period. New evidences of a generalised absence of regeneration in grazed Wooded Grasslands emerged from all the study sites. Some management practices are indicated for the long-term conservation of the habitat.
Ivo Rossetti - One of the best experts on this subject based on the ideXlab platform.
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Mediterranean cork oak Wooded Grasslands: synergies and trade-offs between plant diversity, pasture production and soil carbon
Agroforestry Systems, 2018Co-Authors: Giovanna Seddaiu, L. Salis, Simonetta Bagella, Antonio Pulina, Chiara Cappai, Ivo Rossetti, Roberto Lai, Pier Paolo RoggeroAbstract:Mediterranean Wooded Grasslands that emerge from silvopastoral activities are multifunctional systems that result in high biodiversity and offer ecosystem services such as forage production and soil carbon sequestration. During 3 years, ten grazed Wooded grassland fields were studied in the Berchidda–Monti long-term observatory, located in NE Sardinia, Italy, with the aim of exploring the synergies and trade-offs between biodiversity and selected ecosystem services. Positions below and outside the canopy of three cork oak trees in each field were randomly selected to compare seasonal pasture production, pasture utilization rate by animals, botanical composition, biodiversity indicators (Shannon index and plant species richness) and soil organic carbon. In autumn, dry matter production of pasture was similar in the two positions; in two winters out of three it was greater below the trees than outside, and in spring it was greater outside than below the trees. While plant species richness and Shannon index were not significantly influenced by the position, the overall Wooded grassland plant species richness was 31% higher than that outside of the tree crown. The soil organic carbon content in the 0–40-cm soil layer was also higher below the trees. Our findings highlight that if the main purpose of the Wooded Grasslands is to provide forage for grazing animals rather than conserving and/or enhancing plant diversity and soil fertility, the presence of trees constrains the overall forage productivity, although the greater forage availability in winter under the trees can contribute to improve the seasonal distribution of forage production.
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Isolated cork oak trees affect soil properties and biodiversity in a Mediterranean Wooded grassland
Agriculture Ecosystems & Environment, 2015Co-Authors: Ivo Rossetti, Simonetta Bagella, Chiara Cappai, Pier Paolo Roggero, Maria Carmela Caria, P. Martins Da Silva, José Paulo Sousa, Pascal Querner, Giovanna SeddaiuAbstract:Abstract Mediterranean Wooded Grasslands are multipurpose systems that support high plant and animal diversity levels and are habitats of European importance (i.e., 6310 – Dehesas with evergreen Quercus spp.). Moreover, these systems offer a number of agro-ecosystem services such as forage production, soil carbon sequestration, nutrient recycling and soil protection. The scattered trees enhance the ecological complexity of grassland influencing the soil properties, the herbaceous layer diversity and composition and the soil communities. Understanding how isolated trees influence the other components of the system is essential to comprehend their role supporting high levels of above and below ground biodiversity and ecosystem services. In the present study, we present a hypothetical framework of the effects of isolated trees on soil properties, plant and soil fauna assemblages, the latter here represented by the class Collembola. The floor litter and the associated input of organic matter to the soil was a key factor linking the components of the tree-soil-biodiversity system in a Mediterranean cork oak Wooded grassland. Topsoil C increased by +50% under the tree canopy in comparison with the areas beyond the tree canopy. Plant diversity was lower under tree canopy, but contributed to enhance the total species richness of the grassland. Collembolan diversity was higher under the peculiar conditions beneath the tree canopy. Relationships between plant and collembolan species emerged. The findings of this study suggest that isolated trees have direct and indirect effects on soil properties, plant and collembolan assemblages, hence they can influence the ecological processes of Wooded Grasslands, with implications for food webs, nutrient cycling and productivity of the agro-ecosystem.
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mediterranean quercus suber Wooded Grasslands risk disappearance new evidences from sardinia italy
Forest Ecology and Management, 2014Co-Authors: Ivo Rossetti, Simonetta BagellaAbstract:Wooded Grasslands are the most widespread agro-forestry systems in Europe, and are included in the Natura 2000 network due to their importance in biodiversity conservation. Similar to many man-made systems, long-term Wooded Grasslands conservation depends on sustainable use practices. Regeneration of the tree layer is indispensable to assure Wooded grassland maintenance. Several studies in Spanish dehesas and Portuguese montados generated concerns regarding the long-term conservation of these agro-silvo-pastoral systems. In the present study, we tested if tree regeneration issues documented for the Iberian Peninsula also affected Wooded Grasslands located in another Mediterranean area inside and outside Natura 2000 network. The size structure of Quercus suber L. stands, and the abundance and height of seedlings and saplings were determined at farm and landscape scales, in grazed, grazed and tilled Wooded Grasslands, and non-grazed woodlands to test the compatibility of management type for tree regeneration. A frequency model of size structure was calculated to estimate the probability of cork oak stand survival in a medium and long term time period. New evidences of a generalised absence of regeneration in grazed Wooded Grasslands emerged from all the study sites. Some management practices are indicated for the long-term conservation of the habitat.
Christelle Hély - One of the best experts on this subject based on the ideXlab platform.
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Plant migration and plant communities at the time of the “green Sahara”
Comptes Rendus Geoscience, 2020Co-Authors: Julie Watrin, Anne-marie Lézine, Christelle HélyAbstract:International audienceAround 8500 cal years BP, at the time of the maximum of the African Humid Period, lakes and wetlands expanded in the present-day Sahara while large paleodrainages were formed or re-actived, in response to an orbitally-induced increase in monsoon rainfall. It has been suggested that the direct consequence of this increase in rainfall was the northward displacement of the Sahara/Sahel boundary, thought to have reached 23°N in central and eastern Africa. Here, we show a more complex situation characterized by an increase in biodiversity as the desert accommodated more humid-adapted species from tropical forests and Wooded Grasslands: tropical plant species now found some 400 to 500 km to the south probably entered the desert as gallery-forest formations along rivers and lakes where they benefited from permanent fresh water. At the same time, Saharan trees and shrubs persisted, giving rise to a vegetation that has no analogue today. In this article, we present distribution maps of selected plant species to show both the amplitude of the vegetation change compared to the present and the composition of the past plant communities. We also estimate the migration rate of tropical plant taxa to their northernmost position in the Sahara. This study is based on the use of several data sets: a data set of the modern plant distribution in northern Africa and a data set of modern and fossil pollen sites (from the African Pollen Database, http://fpd.mediasfrance.org/ and http://medias.obs-mip.fr/apd/)
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Plant migration and plant communities at the time of the "green Sahara"
Comptes Rendus Geoscience, 2009Co-Authors: Julie Watrin, Anne-marie Lézine, Christelle HélyAbstract:Abstract Around 8500 cal years BP, at the time of the maximum of the African Humid Period, lakes and wetlands expanded in the present-day Sahara while large paleodrainages were formed or re-actived, in response to an orbitally-induced increase in monsoon rainfall. It has been suggested that the direct consequence of this increase in rainfall was the northward displacement of the Sahara/Sahel boundary, thought to have reached 23°N in central and eastern Africa. Here, we show a more complex situation characterized by an increase in biodiversity as the desert accommodated more humid-adapted species from tropical forests and Wooded Grasslands: tropical plant species now found some 400 to 500 km to the south probably entered the desert as gallery-forest formations along rivers and lakes where they benefited from permanent fresh water. At the same time, Saharan trees and shrubs persisted, giving rise to a vegetation that has no analogue today. In this article, we present distribution maps of selected plant species to show both the amplitude of the vegetation change compared to the present and the composition of the past plant communities. We also estimate the migration rate of tropical plant taxa to their northernmost position in the Sahara. This study is based on the use of several data sets: a data set of the modern plant distribution in northern Africa and a data set of modern and fossil pollen sites (from the African Pollen Database, http://fpd.mediasfrance.org/ and http://medias.obs-mip.fr/apd/ ).
Giovanna Seddaiu - One of the best experts on this subject based on the ideXlab platform.
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Mediterranean cork oak Wooded Grasslands: synergies and trade-offs between plant diversity, pasture production and soil carbon
Agroforestry Systems, 2018Co-Authors: Giovanna Seddaiu, L. Salis, Simonetta Bagella, Antonio Pulina, Chiara Cappai, Ivo Rossetti, Roberto Lai, Pier Paolo RoggeroAbstract:Mediterranean Wooded Grasslands that emerge from silvopastoral activities are multifunctional systems that result in high biodiversity and offer ecosystem services such as forage production and soil carbon sequestration. During 3 years, ten grazed Wooded grassland fields were studied in the Berchidda–Monti long-term observatory, located in NE Sardinia, Italy, with the aim of exploring the synergies and trade-offs between biodiversity and selected ecosystem services. Positions below and outside the canopy of three cork oak trees in each field were randomly selected to compare seasonal pasture production, pasture utilization rate by animals, botanical composition, biodiversity indicators (Shannon index and plant species richness) and soil organic carbon. In autumn, dry matter production of pasture was similar in the two positions; in two winters out of three it was greater below the trees than outside, and in spring it was greater outside than below the trees. While plant species richness and Shannon index were not significantly influenced by the position, the overall Wooded grassland plant species richness was 31% higher than that outside of the tree crown. The soil organic carbon content in the 0–40-cm soil layer was also higher below the trees. Our findings highlight that if the main purpose of the Wooded Grasslands is to provide forage for grazing animals rather than conserving and/or enhancing plant diversity and soil fertility, the presence of trees constrains the overall forage productivity, although the greater forage availability in winter under the trees can contribute to improve the seasonal distribution of forage production.
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Biomass and allometry of cork oak trees growing under different land uses in silvo-pastoral ecosystems
2017Co-Authors: Laura P. Leites, Chiara Cappai, Alex Curtze, Q. Johnson, Lauren Ann Onofrio, G. Smith, S. F. Campus, Giovanna SeddaiuAbstract:This study focuses in three LUT: woodlands (W), Wooded Grasslands (WG), and open Grasslands (OG). Four sites were selected with three sites having all three LUT and one site having only W.
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Isolated cork oak trees affect soil properties and biodiversity in a Mediterranean Wooded grassland
Agriculture Ecosystems & Environment, 2015Co-Authors: Ivo Rossetti, Simonetta Bagella, Chiara Cappai, Pier Paolo Roggero, Maria Carmela Caria, P. Martins Da Silva, José Paulo Sousa, Pascal Querner, Giovanna SeddaiuAbstract:Abstract Mediterranean Wooded Grasslands are multipurpose systems that support high plant and animal diversity levels and are habitats of European importance (i.e., 6310 – Dehesas with evergreen Quercus spp.). Moreover, these systems offer a number of agro-ecosystem services such as forage production, soil carbon sequestration, nutrient recycling and soil protection. The scattered trees enhance the ecological complexity of grassland influencing the soil properties, the herbaceous layer diversity and composition and the soil communities. Understanding how isolated trees influence the other components of the system is essential to comprehend their role supporting high levels of above and below ground biodiversity and ecosystem services. In the present study, we present a hypothetical framework of the effects of isolated trees on soil properties, plant and soil fauna assemblages, the latter here represented by the class Collembola. The floor litter and the associated input of organic matter to the soil was a key factor linking the components of the tree-soil-biodiversity system in a Mediterranean cork oak Wooded grassland. Topsoil C increased by +50% under the tree canopy in comparison with the areas beyond the tree canopy. Plant diversity was lower under tree canopy, but contributed to enhance the total species richness of the grassland. Collembolan diversity was higher under the peculiar conditions beneath the tree canopy. Relationships between plant and collembolan species emerged. The findings of this study suggest that isolated trees have direct and indirect effects on soil properties, plant and collembolan assemblages, hence they can influence the ecological processes of Wooded Grasslands, with implications for food webs, nutrient cycling and productivity of the agro-ecosystem.
Julie Watrin - One of the best experts on this subject based on the ideXlab platform.
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Plant migration and plant communities at the time of the “green Sahara”
Comptes Rendus Geoscience, 2020Co-Authors: Julie Watrin, Anne-marie Lézine, Christelle HélyAbstract:International audienceAround 8500 cal years BP, at the time of the maximum of the African Humid Period, lakes and wetlands expanded in the present-day Sahara while large paleodrainages were formed or re-actived, in response to an orbitally-induced increase in monsoon rainfall. It has been suggested that the direct consequence of this increase in rainfall was the northward displacement of the Sahara/Sahel boundary, thought to have reached 23°N in central and eastern Africa. Here, we show a more complex situation characterized by an increase in biodiversity as the desert accommodated more humid-adapted species from tropical forests and Wooded Grasslands: tropical plant species now found some 400 to 500 km to the south probably entered the desert as gallery-forest formations along rivers and lakes where they benefited from permanent fresh water. At the same time, Saharan trees and shrubs persisted, giving rise to a vegetation that has no analogue today. In this article, we present distribution maps of selected plant species to show both the amplitude of the vegetation change compared to the present and the composition of the past plant communities. We also estimate the migration rate of tropical plant taxa to their northernmost position in the Sahara. This study is based on the use of several data sets: a data set of the modern plant distribution in northern Africa and a data set of modern and fossil pollen sites (from the African Pollen Database, http://fpd.mediasfrance.org/ and http://medias.obs-mip.fr/apd/)
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Plant migration and plant communities at the time of the "green Sahara"
Comptes Rendus Geoscience, 2009Co-Authors: Julie Watrin, Anne-marie Lézine, Christelle HélyAbstract:Abstract Around 8500 cal years BP, at the time of the maximum of the African Humid Period, lakes and wetlands expanded in the present-day Sahara while large paleodrainages were formed or re-actived, in response to an orbitally-induced increase in monsoon rainfall. It has been suggested that the direct consequence of this increase in rainfall was the northward displacement of the Sahara/Sahel boundary, thought to have reached 23°N in central and eastern Africa. Here, we show a more complex situation characterized by an increase in biodiversity as the desert accommodated more humid-adapted species from tropical forests and Wooded Grasslands: tropical plant species now found some 400 to 500 km to the south probably entered the desert as gallery-forest formations along rivers and lakes where they benefited from permanent fresh water. At the same time, Saharan trees and shrubs persisted, giving rise to a vegetation that has no analogue today. In this article, we present distribution maps of selected plant species to show both the amplitude of the vegetation change compared to the present and the composition of the past plant communities. We also estimate the migration rate of tropical plant taxa to their northernmost position in the Sahara. This study is based on the use of several data sets: a data set of the modern plant distribution in northern Africa and a data set of modern and fossil pollen sites (from the African Pollen Database, http://fpd.mediasfrance.org/ and http://medias.obs-mip.fr/apd/ ).
