A taxonomic database system CARipé with integrated links to plant images was constructed to chara... more A taxonomic database system CARipé with integrated links to plant images was constructed to characterize the 800 forest tree species recorded for the catchments of the Rio Grande in the south of Minas Gerais state in Brazil using vegetative morphology. After a description was ready, its integrated system Empar, completed in a few seconds an identification attempt using automatic character correlation. Empar proved operationally successful in identification tests of 62 specimens, of as many species, against 554 reference specimens and species from the ESAL Herbarium. Empar employed a similarity coefficient with the option of a weighting based on character frequency and, in tests, the use of this rarity weighting further improved the performance. Three tree groups based on leaf type and phyllotaxy were analyzed separately. From the start, those with compound leaves received more descriptors and the result was little difference in identification performance between the tree groups. Indications were that experts and non-experts performed characterizations for identification purposes almost equally well. The most important result was that successful identifications were obtained using a reference base of just one specimen description per species.
Esta obra destina-se aqueles interessados em ecologia vegetal, levantamentos de flora e botânica ... more Esta obra destina-se aqueles interessados em ecologia vegetal, levantamentos de flora e botânica em geral. Aborda tema fundamental para a preservacao de especies arboreas, uma vez que a area estudada e prioritaria para conservacao segundo Drummond (2005). Os parâmetros fitossociologicos mostraram como algumas especies de arvores nativas do dominio atlântico sao importantes na caracterizacao de zonas de tensao ecologica dentro do dominio, assim como apontou varias outras como ameacadas ou correndo perigo de extincao. A elevada riqueza floristica encontrada tanto nos corredores (naturais ou antropicos) quanto nas florestas de cabeceira corroboram com a manutencao de pequenas manchas florestais como mantenedoras de biodiversidade, ressaltando ainda mais a criacao e fortalecimento de politicas publicas que visem a protecao e a conexao destas manchas no sul do estado de Minas Gerais.
QuestionsForest's above‐ground biomass is an important component of the global carbon cycle a... more QuestionsForest's above‐ground biomass is an important component of the global carbon cycle and, in forest fragments, it tends to decrease near the edges. This edge effect on biomass can be due to the number and identity of species residing at edges or due to the context of edges constraining plant functioning regardless of the species. Here, we took advantage of species‐rich natural forest edges to test the role of species richness, composition, and context dependency in explaining why forest edges stock less above‐ground biomass than interiors.LocationGallery forests in Brazilian savanna (latitude 21° S, longitude 44° W).MethodsWe tested the relationship between species richness and above‐ground biomass in 49 forest plots (10,142 trees). We used a novel adaptation of the Price equation to calculate the impact of species composition (losses and gains) and context dependency on the differences of above‐ground biomass between edges and interiors.ResultsDifferences in species richness and composition did not explain the lower above‐ground biomass of forest edges when compared to interiors. Biomass responses were context‐dependent, in which the same species achieved smaller sizes when it grew in the edge than in the interior.ConclusionsOur study shows that edge effects on biomass may operate independently of biodiversity as edges and interiors had a similar number of species but distinct above‐ground biomass. Indeed, in the studied natural forest patches, the edge context itself limits plant size and, thus, the above‐ground biomass stock. Beyond unveiling the underlying causes of edge effects on forest biomass, our results call for distinct policies to conserve both the carbon stocks in forest interiors but also the unique diversity of natural edges.
Deadwood is a large global carbon store with its store size partially determined by biotic decay.... more Deadwood is a large global carbon store with its store size partially determined by biotic decay. Microbial wood decay rates are known to respond to changing temperature and precipitation. Termites are also important decomposers in the tropics but are less well studied. An understanding of their climate sensitivities is needed to estimate climate change effects on wood carbon pools. Using data from 133 sites spanning six continents, we found that termite wood discovery and consumption were highly sensitive to temperature (with decay increasing >6.8 times per 10°C increase in temperature)—even more so than microbes. Termite decay effects were greatest in tropical seasonal forests, tropical savannas, and subtropical deserts. With tropicalization (i.e., warming shifts to tropical climates), termite wood decay will likely increase as termites access more of Earth’s surface.
Understanding the mechanisms controlling forest carbon storage is crucial to support “nature-base... more Understanding the mechanisms controlling forest carbon storage is crucial to support “nature-based” solutions for climate change mitigation. We used a dataset of 892 Atlantic Forest inventories to assess the direct and indirect effects of environmental conditions, human impacts, tree community proprieties, and sampling methods on tree above-ground carbon stocks. We showed that the widely accepted drivers of carbon stocks, such as climate, soil, topography, and forest fragmentation, have a much smaller role than the forest disturbance history and functional proprieties of the Atlantic Forest. Specifically, within-forest disturbance level was the most important driver, with effect at least 30% higher than any of the environmental conditions individually. Thus, our findings suggest that the conservation of tropical carbon stocks may be dependable on, principally, avoiding forest degradation and that conservation policies focusing only on carbon may fail to protect tropical biodiversity.
PremiseEpiphytes have commensal relationships with their host trees. Besides the influence of tre... more PremiseEpiphytes have commensal relationships with their host trees. Besides the influence of tree traits, little has been discussed concerning the ecology of epiphytes in disturbed habitats (e.g., pasture). We herein tested whether the occurrences of pasture and forest specialist epiphytes in pastures are affected differently by tree traits. We hypothesized that (H1) the richness and abundance of generalist epiphytes would be positively associated with area availability; (H2) the richness and abundance of forest epiphyte species would be associated both with (H2.a) area availability and (H2.b) tree traits related to higher seed adherence, and/or (H2.c) less severe habitat (e.g., high humidity and more shade).MethodsWe sampled 9567 epiphyte individuals from 16 species on 759 scattered remnant trees. The epiphyte species were divided into two ecological groups: forest specialists and pasture specialists. We evaluated four host tree traits: two related to tree size (crown area and tru...
Abstract Climate, topography and edaphic characteristics are important factors for plant communit... more Abstract Climate, topography and edaphic characteristics are important factors for plant community dynamics when considering spatial and temporal scales. Efforts on vegetation dynamics in tropical regions are mostly focused on forests, with far less attention dedicated to open vegetation ecosystems. This study aimed to understand how demographic rates (based on models and maps) are affected by climate, soil and terrain variables in the Brazilian savanna, the Cerrado, which is a hotspot for the world biodiversity conservation. To do so, we used forest inventory data collected from 354 plots (10 × 100 m) distributed in the savanna of Minas Gerais State, southeast of Brazil, in the years of 2005–2006 and 2010–2011. Next, we calculated the rates of mortality, recruitment, net change in number of individuals, basal area loss and gain, and net change in basal area for the plots. We used the Random Forest (RF) algorithm to model the demographic rates in function of climate, soil and terrain variables obtained from the WorldClim 2, Harmonized World Soil Database and Shuttle Radar Topography Mission (SRTM), respectively. The models presented good performance with coefficient of determination (R2) values ranging from 0.68 to 0.84, mean absolute error (MAE) between 0.32 and 0.96%.year−1, and root mean square error (RMSE) ranging from 60 a 160%. The recruitment was higher than mortality, and the basal area gain was greater than the basal area loss, resulting in positive net change rates. The most important variables for the model and best predictors of vegetation dynamics rates of Brazilian savanna were the terrain variables, since they encompass characteristics such as soil water content, erosion, altitudes and slope. We showed that the gain in number of individuals and basal area were greater at low regions, that is, near drainage lines and with higher humidity. The losses in number of individuals and basal area were higher in boundary regions of the savanna vegetation, that is, regions of higher altitude and consequently, low humidity. Therefore, our findings provide support for conservation and management strategies of the biome, since from the vegetation dynamics drivers identification, we may identify priority areas as well as the vegetation vulnerability.
A taxonomic database system CARipé with integrated links to plant images was constructed to chara... more A taxonomic database system CARipé with integrated links to plant images was constructed to characterize the 800 forest tree species recorded for the catchments of the Rio Grande in the south of Minas Gerais state in Brazil using vegetative morphology. After a description was ready, its integrated system Empar, completed in a few seconds an identification attempt using automatic character correlation. Empar proved operationally successful in identification tests of 62 specimens, of as many species, against 554 reference specimens and species from the ESAL Herbarium. Empar employed a similarity coefficient with the option of a weighting based on character frequency and, in tests, the use of this rarity weighting further improved the performance. Three tree groups based on leaf type and phyllotaxy were analyzed separately. From the start, those with compound leaves received more descriptors and the result was little difference in identification performance between the tree groups. Indications were that experts and non-experts performed characterizations for identification purposes almost equally well. The most important result was that successful identifications were obtained using a reference base of just one specimen description per species.
Esta obra destina-se aqueles interessados em ecologia vegetal, levantamentos de flora e botânica ... more Esta obra destina-se aqueles interessados em ecologia vegetal, levantamentos de flora e botânica em geral. Aborda tema fundamental para a preservacao de especies arboreas, uma vez que a area estudada e prioritaria para conservacao segundo Drummond (2005). Os parâmetros fitossociologicos mostraram como algumas especies de arvores nativas do dominio atlântico sao importantes na caracterizacao de zonas de tensao ecologica dentro do dominio, assim como apontou varias outras como ameacadas ou correndo perigo de extincao. A elevada riqueza floristica encontrada tanto nos corredores (naturais ou antropicos) quanto nas florestas de cabeceira corroboram com a manutencao de pequenas manchas florestais como mantenedoras de biodiversidade, ressaltando ainda mais a criacao e fortalecimento de politicas publicas que visem a protecao e a conexao destas manchas no sul do estado de Minas Gerais.
QuestionsForest's above‐ground biomass is an important component of the global carbon cycle a... more QuestionsForest's above‐ground biomass is an important component of the global carbon cycle and, in forest fragments, it tends to decrease near the edges. This edge effect on biomass can be due to the number and identity of species residing at edges or due to the context of edges constraining plant functioning regardless of the species. Here, we took advantage of species‐rich natural forest edges to test the role of species richness, composition, and context dependency in explaining why forest edges stock less above‐ground biomass than interiors.LocationGallery forests in Brazilian savanna (latitude 21° S, longitude 44° W).MethodsWe tested the relationship between species richness and above‐ground biomass in 49 forest plots (10,142 trees). We used a novel adaptation of the Price equation to calculate the impact of species composition (losses and gains) and context dependency on the differences of above‐ground biomass between edges and interiors.ResultsDifferences in species richness and composition did not explain the lower above‐ground biomass of forest edges when compared to interiors. Biomass responses were context‐dependent, in which the same species achieved smaller sizes when it grew in the edge than in the interior.ConclusionsOur study shows that edge effects on biomass may operate independently of biodiversity as edges and interiors had a similar number of species but distinct above‐ground biomass. Indeed, in the studied natural forest patches, the edge context itself limits plant size and, thus, the above‐ground biomass stock. Beyond unveiling the underlying causes of edge effects on forest biomass, our results call for distinct policies to conserve both the carbon stocks in forest interiors but also the unique diversity of natural edges.
Deadwood is a large global carbon store with its store size partially determined by biotic decay.... more Deadwood is a large global carbon store with its store size partially determined by biotic decay. Microbial wood decay rates are known to respond to changing temperature and precipitation. Termites are also important decomposers in the tropics but are less well studied. An understanding of their climate sensitivities is needed to estimate climate change effects on wood carbon pools. Using data from 133 sites spanning six continents, we found that termite wood discovery and consumption were highly sensitive to temperature (with decay increasing >6.8 times per 10°C increase in temperature)—even more so than microbes. Termite decay effects were greatest in tropical seasonal forests, tropical savannas, and subtropical deserts. With tropicalization (i.e., warming shifts to tropical climates), termite wood decay will likely increase as termites access more of Earth’s surface.
Understanding the mechanisms controlling forest carbon storage is crucial to support “nature-base... more Understanding the mechanisms controlling forest carbon storage is crucial to support “nature-based” solutions for climate change mitigation. We used a dataset of 892 Atlantic Forest inventories to assess the direct and indirect effects of environmental conditions, human impacts, tree community proprieties, and sampling methods on tree above-ground carbon stocks. We showed that the widely accepted drivers of carbon stocks, such as climate, soil, topography, and forest fragmentation, have a much smaller role than the forest disturbance history and functional proprieties of the Atlantic Forest. Specifically, within-forest disturbance level was the most important driver, with effect at least 30% higher than any of the environmental conditions individually. Thus, our findings suggest that the conservation of tropical carbon stocks may be dependable on, principally, avoiding forest degradation and that conservation policies focusing only on carbon may fail to protect tropical biodiversity.
PremiseEpiphytes have commensal relationships with their host trees. Besides the influence of tre... more PremiseEpiphytes have commensal relationships with their host trees. Besides the influence of tree traits, little has been discussed concerning the ecology of epiphytes in disturbed habitats (e.g., pasture). We herein tested whether the occurrences of pasture and forest specialist epiphytes in pastures are affected differently by tree traits. We hypothesized that (H1) the richness and abundance of generalist epiphytes would be positively associated with area availability; (H2) the richness and abundance of forest epiphyte species would be associated both with (H2.a) area availability and (H2.b) tree traits related to higher seed adherence, and/or (H2.c) less severe habitat (e.g., high humidity and more shade).MethodsWe sampled 9567 epiphyte individuals from 16 species on 759 scattered remnant trees. The epiphyte species were divided into two ecological groups: forest specialists and pasture specialists. We evaluated four host tree traits: two related to tree size (crown area and tru...
Abstract Climate, topography and edaphic characteristics are important factors for plant communit... more Abstract Climate, topography and edaphic characteristics are important factors for plant community dynamics when considering spatial and temporal scales. Efforts on vegetation dynamics in tropical regions are mostly focused on forests, with far less attention dedicated to open vegetation ecosystems. This study aimed to understand how demographic rates (based on models and maps) are affected by climate, soil and terrain variables in the Brazilian savanna, the Cerrado, which is a hotspot for the world biodiversity conservation. To do so, we used forest inventory data collected from 354 plots (10 × 100 m) distributed in the savanna of Minas Gerais State, southeast of Brazil, in the years of 2005–2006 and 2010–2011. Next, we calculated the rates of mortality, recruitment, net change in number of individuals, basal area loss and gain, and net change in basal area for the plots. We used the Random Forest (RF) algorithm to model the demographic rates in function of climate, soil and terrain variables obtained from the WorldClim 2, Harmonized World Soil Database and Shuttle Radar Topography Mission (SRTM), respectively. The models presented good performance with coefficient of determination (R2) values ranging from 0.68 to 0.84, mean absolute error (MAE) between 0.32 and 0.96%.year−1, and root mean square error (RMSE) ranging from 60 a 160%. The recruitment was higher than mortality, and the basal area gain was greater than the basal area loss, resulting in positive net change rates. The most important variables for the model and best predictors of vegetation dynamics rates of Brazilian savanna were the terrain variables, since they encompass characteristics such as soil water content, erosion, altitudes and slope. We showed that the gain in number of individuals and basal area were greater at low regions, that is, near drainage lines and with higher humidity. The losses in number of individuals and basal area were higher in boundary regions of the savanna vegetation, that is, regions of higher altitude and consequently, low humidity. Therefore, our findings provide support for conservation and management strategies of the biome, since from the vegetation dynamics drivers identification, we may identify priority areas as well as the vegetation vulnerability.
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Papers by Eduardo van den Berg