QuestionsPlant communities in transitional zones between ecosystem types have potentially a large... more QuestionsPlant communities in transitional zones between ecosystem types have potentially a large range of ecological strategies, even along short gradients. Exploring these regional differences and the drivers of variation is important to understand plant adaptations and changes in ecological processes between distinct ecosystems. Here, we ask whether distinct forest types in the subtropical region present plant communities with distinct ecological strategies and, if so, if these differences are driven by climatic variables.LocationSubtropical forests in southern Brazil.MethodsWe compiled species lists from 112 sites distributed across rainforests, seasonal forests, Araucaria forests and Pampean forests. We used Grime's CSR scheme and calculated, for each species, CSR values based on information of three leaf traits: leaf area, specific leaf area and leaf dry matter content. Species CSR values were used to calculate the mean value for each community. We selected four climatic variables related to temperate and precipitation and analyzed their influence on plant strategies by linear mixed models.ResultsOur results showed a strong CS component for all subtropical forests studied, with a small contribution from component R. We found clear differences in ecological strategies between forest types: rainforest showed the highest values of component C, and Araucaria and Pampean forests presented the highest values of component S. We found a strong influence of temperature variables on ecological strategies.ConclusionsEven along a short latitudinal gradient, we found differences in ecological strategies across forest types. Araucaria and Pampean forests were strongly associated with the stress‐tolerant strategy, as they face lower minimum temperatures and/or a larger temperature range, whereas rainforests, which face warmer temperatures and a lower range of variation, presented a strategy where competition is of higher importance. This highlights that regional environmental conditions in this transitional zone influence ecological strategies of tree communities.
Ecological restoration of degraded areas can be important to prevent or slow down invasions of al... more Ecological restoration of degraded areas can be important to prevent or slow down invasions of alien species. The objective of this study is to evaluate the potential of native species in applying the seeding technique and to compete with the invader Eragrostis plana, aiming ecological restoration at Campos Sulinos grasslands (South Brazil). Seeds of six native species (Anthaenantia lanata, Aristida laevis, Aristida jubata, Chamaecrista repens, Panicum olyroides and Paspalum plicatulum) and of E. plana were sown in isolated and competition (one native species plus the invader) pots. Germination rate, survival rate, germination rate index (GRI), above and belowground biomass were analyzed using ANOVAs and GLMs, and the impact of native species’ attributes at the invader biomass were analyzed using linear regressions. We found that Arista laevis and A. jubata had the highest germination and GRI, although had low survival. Anthaenantia lanata and Paspalum plicatulum had medium germinat...
Here we provide the ‘Global Spectrum of Plant Form and Function Dataset’, containing species mean... more Here we provide the ‘Global Spectrum of Plant Form and Function Dataset’, containing species mean values for six vascular plant traits. Together, these traits –plant height, stem specific density, leaf area, leaf mass per area, leaf nitrogen content per dry mass, and diaspore (seed or spore) mass – define the primary axes of variation in plant form and function. The dataset is based on ca. 1 million trait records received via the TRY database (representing ca. 2,500 original publications) and additional unpublished data. It provides 92,159 species mean values for the six traits, covering 46,047 species. The data are complemented by higher-level taxonomic classification and six categorical traits (woodiness, growth form, succulence, adaptation to terrestrial or aquatic habitats, nutrition type and leaf type). Data quality management is based on a probabilistic approach combined with comprehensive validation against expert knowledge and external information. Intense data acquisition a...
Secondary forests originate from natural regeneration after fallow (succession) or restoration. S... more Secondary forests originate from natural regeneration after fallow (succession) or restoration. Species assembly in these communities, which can affect ecosystem functions and successional trajectories, is very unpredictable. Trait-based trajectories can shed light on the recovery of ecosystem functions and enable predictions of how the regenerating communities will change with forest age. Regeneration communities are affected by initial conditions and also by canopy structure and functional traits that alter dispersers' attractiveness and coexistence mechanisms. Here we evaluated how community functional traits change over time and tested if functional diversity and composition of the established canopy, as well as the structure of the canopy and forest age, influence the functional structure of regenerating tree communities when compared to their reference forests. For this, we calculated dissimilarity in trait composition (community-weighted means) and in functional diversity...
Abstract Subtropical forests certainly contribute to terrestrial global carbon storage, but we ha... more Abstract Subtropical forests certainly contribute to terrestrial global carbon storage, but we have limited understanding about the relative amounts and of the drivers of above-ground biomass (AGB) variation in their region. Here we assess the spatial distribution and drivers of AGB in 119 sites across the South American subtropical forests. We applied a structural equation modelling approach to test the causal relationships between AGB and environmental (climate and soil), structural (proportion of large-sized trees) and community (functional and species diversity and composition) variables. The AGB on subtropical forests is on average 246 Mg ha−1. Biomass stocks were driven directly by temperature annual range and the proportion of large-sized trees, whilst soil texture, community mean leaf nitrogen content and functional diversity had no predictive power. Temperature annual range had a negative effect on AGB, indicating that communities under strong thermal amplitude across the year tend to accumulate less AGB. The positive effect of large-sized trees indicates that mature forests are playing a key role in the long-term persistence of carbon storage, as these large trees account for 64% of total biomass stored in these forests. Our study reinforces the importance of structurally complex subtropical forest remnants for maximising carbon storage, especially facing future climatic changes predicted for the region.
O processo de expansão florestal tem sido observado em regiões de mosaicos de campo-floresta no S... more O processo de expansão florestal tem sido observado em regiões de mosaicos de campo-floresta no Sul do Brasil, especialmente em campos excluídos de fogo e pastejo. Outros fatores influenciam esse processo, porém a magnitude ainda permanece pouco compreendida. Neste estudo, avaliamos os padrões da vegetação lenhosa estabelecida num campo excluído de manejo por 34 anos, relacionando-os com variáveis de solo e espaço. Estabelecemos 110 parcelas (113 m2 cada) de forma sistemática sobre áreas mapeadas como campos em 1985, na Estação Ecológica de Aracuri, Rio Grande do Sul, Brasil. Foram amostrados todos os indivíduos lenhosos e variáveis de solo. Análises de ordenação e de partição da variância da composição de espécies nos componentes solo, espaço, e solo estruturado no espaço foram empregadas. Os padrões da vegetação foram melhor explicados pelo espaço, principalmente a distância da área fonte florestal. Comunidades mais próximas da antiga borda florestal são caracterizadas por mais es...
QuestionsPlant communities in transitional zones between ecosystem types have potentially a large... more QuestionsPlant communities in transitional zones between ecosystem types have potentially a large range of ecological strategies, even along short gradients. Exploring these regional differences and the drivers of variation is important to understand plant adaptations and changes in ecological processes between distinct ecosystems. Here, we ask whether distinct forest types in the subtropical region present plant communities with distinct ecological strategies and, if so, if these differences are driven by climatic variables.LocationSubtropical forests in southern Brazil.MethodsWe compiled species lists from 112 sites distributed across rainforests, seasonal forests, Araucaria forests and Pampean forests. We used Grime's CSR scheme and calculated, for each species, CSR values based on information of three leaf traits: leaf area, specific leaf area and leaf dry matter content. Species CSR values were used to calculate the mean value for each community. We selected four climatic variables related to temperate and precipitation and analyzed their influence on plant strategies by linear mixed models.ResultsOur results showed a strong CS component for all subtropical forests studied, with a small contribution from component R. We found clear differences in ecological strategies between forest types: rainforest showed the highest values of component C, and Araucaria and Pampean forests presented the highest values of component S. We found a strong influence of temperature variables on ecological strategies.ConclusionsEven along a short latitudinal gradient, we found differences in ecological strategies across forest types. Araucaria and Pampean forests were strongly associated with the stress‐tolerant strategy, as they face lower minimum temperatures and/or a larger temperature range, whereas rainforests, which face warmer temperatures and a lower range of variation, presented a strategy where competition is of higher importance. This highlights that regional environmental conditions in this transitional zone influence ecological strategies of tree communities.
Ecological restoration of degraded areas can be important to prevent or slow down invasions of al... more Ecological restoration of degraded areas can be important to prevent or slow down invasions of alien species. The objective of this study is to evaluate the potential of native species in applying the seeding technique and to compete with the invader Eragrostis plana, aiming ecological restoration at Campos Sulinos grasslands (South Brazil). Seeds of six native species (Anthaenantia lanata, Aristida laevis, Aristida jubata, Chamaecrista repens, Panicum olyroides and Paspalum plicatulum) and of E. plana were sown in isolated and competition (one native species plus the invader) pots. Germination rate, survival rate, germination rate index (GRI), above and belowground biomass were analyzed using ANOVAs and GLMs, and the impact of native species’ attributes at the invader biomass were analyzed using linear regressions. We found that Arista laevis and A. jubata had the highest germination and GRI, although had low survival. Anthaenantia lanata and Paspalum plicatulum had medium germinat...
Here we provide the ‘Global Spectrum of Plant Form and Function Dataset’, containing species mean... more Here we provide the ‘Global Spectrum of Plant Form and Function Dataset’, containing species mean values for six vascular plant traits. Together, these traits –plant height, stem specific density, leaf area, leaf mass per area, leaf nitrogen content per dry mass, and diaspore (seed or spore) mass – define the primary axes of variation in plant form and function. The dataset is based on ca. 1 million trait records received via the TRY database (representing ca. 2,500 original publications) and additional unpublished data. It provides 92,159 species mean values for the six traits, covering 46,047 species. The data are complemented by higher-level taxonomic classification and six categorical traits (woodiness, growth form, succulence, adaptation to terrestrial or aquatic habitats, nutrition type and leaf type). Data quality management is based on a probabilistic approach combined with comprehensive validation against expert knowledge and external information. Intense data acquisition a...
Secondary forests originate from natural regeneration after fallow (succession) or restoration. S... more Secondary forests originate from natural regeneration after fallow (succession) or restoration. Species assembly in these communities, which can affect ecosystem functions and successional trajectories, is very unpredictable. Trait-based trajectories can shed light on the recovery of ecosystem functions and enable predictions of how the regenerating communities will change with forest age. Regeneration communities are affected by initial conditions and also by canopy structure and functional traits that alter dispersers' attractiveness and coexistence mechanisms. Here we evaluated how community functional traits change over time and tested if functional diversity and composition of the established canopy, as well as the structure of the canopy and forest age, influence the functional structure of regenerating tree communities when compared to their reference forests. For this, we calculated dissimilarity in trait composition (community-weighted means) and in functional diversity...
Abstract Subtropical forests certainly contribute to terrestrial global carbon storage, but we ha... more Abstract Subtropical forests certainly contribute to terrestrial global carbon storage, but we have limited understanding about the relative amounts and of the drivers of above-ground biomass (AGB) variation in their region. Here we assess the spatial distribution and drivers of AGB in 119 sites across the South American subtropical forests. We applied a structural equation modelling approach to test the causal relationships between AGB and environmental (climate and soil), structural (proportion of large-sized trees) and community (functional and species diversity and composition) variables. The AGB on subtropical forests is on average 246 Mg ha−1. Biomass stocks were driven directly by temperature annual range and the proportion of large-sized trees, whilst soil texture, community mean leaf nitrogen content and functional diversity had no predictive power. Temperature annual range had a negative effect on AGB, indicating that communities under strong thermal amplitude across the year tend to accumulate less AGB. The positive effect of large-sized trees indicates that mature forests are playing a key role in the long-term persistence of carbon storage, as these large trees account for 64% of total biomass stored in these forests. Our study reinforces the importance of structurally complex subtropical forest remnants for maximising carbon storage, especially facing future climatic changes predicted for the region.
O processo de expansão florestal tem sido observado em regiões de mosaicos de campo-floresta no S... more O processo de expansão florestal tem sido observado em regiões de mosaicos de campo-floresta no Sul do Brasil, especialmente em campos excluídos de fogo e pastejo. Outros fatores influenciam esse processo, porém a magnitude ainda permanece pouco compreendida. Neste estudo, avaliamos os padrões da vegetação lenhosa estabelecida num campo excluído de manejo por 34 anos, relacionando-os com variáveis de solo e espaço. Estabelecemos 110 parcelas (113 m2 cada) de forma sistemática sobre áreas mapeadas como campos em 1985, na Estação Ecológica de Aracuri, Rio Grande do Sul, Brasil. Foram amostrados todos os indivíduos lenhosos e variáveis de solo. Análises de ordenação e de partição da variância da composição de espécies nos componentes solo, espaço, e solo estruturado no espaço foram empregadas. Os padrões da vegetação foram melhor explicados pelo espaço, principalmente a distância da área fonte florestal. Comunidades mais próximas da antiga borda florestal são caracterizadas por mais es...
Uploads
Papers by Sandra Muller