Effects of climate and forest structure on palms, bromeliads and bamboos in Atlantic Forest fragments of Northeastern Brazil / Efeitos do clima e da estrutura da vegetação em palmeiras, bromélias e bambus em fragmentos de Mata Atlântica no nordeste brasileiro

Palms, bromeliads and bamboos are key elements of tropical forests and understanding the effects of climate, anthropogenic pressure and forest structure on these groups is crucial to forecast structural changes in tropical forests. Therefore, we investigated the effects of these factors on the abundance of these groups in 22 Atlantic forest fragments of Northeastern Brazil. Abundance of bromeliads and bamboos were assessed through indexes. Palms were counted within a radius of 20 m. We also obtained measures of vegetation structure, fragment size, annual precipitation, precipitation seasonality and human population density. We tested the effects of these predictors on plant groups using path analysis. Palm abundance was higher in taller forests with larger trees, closed canopy and sparse understory, which may be a result of the presence of seed dispersers and specific attributes of local palm species. Bromeliads were negatively affected by both annual precipitation and precipitation seasonality, what may reflect adaptations of these plants to use water efficiently, but also the need to capture water in a regular basis. Bamboos were not related to any predictor variable. As climate and forest structure affected the abundance of bromeliads and palms, human-induced climatic changes and disturbances in forest structure may modify the abundance of these groups. In addition, soil properties and direct measurements of human disturbance should be used in future studies in order to improve the predictability of models about plant groups in Northeastern Atlantic Forest.(AU)

Palmeiras, bromélias e bambus são importantes elementos das florestas tropicais e, entender os efeitos do clima, pressão antrópica e estrutura da floresta nesses grupos é crucial para prever alterações estruturais em florestas tropicais. Portanto, nós investigamos os efeitos desses fatores na abundância desses grupos vegetais em 22 fragmentos de Mata Atlântica no nordeste brasileiro. Abundâncias de bromélias e bambus foram registradas através de índices. Palmeiras foram contadas em um raio de 20 m. Nós também obtemos medidas da estrutura da vegetação, tamanho de fragmento, precipitação anual, sazonalidade na precipitação e densidade populacional humana. Nós testamos os efeitos desses preditores nos grupos vegetais através de análises de caminhos. A abundância de palmeiras foi maior em florestas mais altas, com árvores mais grossas, dossel fechado e sub-bosque aberto, o que deve refletir a presença de dispersores de sementes e atributos específicos das espécies de palmeiras locais. Bromélias foram negativamente afetadas pela precipitação anual e pela sazonalidade na precipitação, o que deve refletir adaptações dessas plantas para o uso eficiente da água, mas também a necessidade de captar água regularmente. Bambus não estiveram relacionados com nenhum dos preditores avaliados. Dado que clima e estrutura florestal afetaram a abundância de bromélias e palmeiras, as mudanças climáticas e distúrbios na estrutura das matas causados por ações antrópicas podem alterar a abundância desses grupos. Adicionalmente, propriedades do solo e medidas diretas de distúrbios antrópicos devem ser usadas em estudos futuros para melhorar o poder preditivo dos modelos sobre a abundância de plantas na Mata Atlântica do nordeste brasileiro.(AU)

Effects of climate and forest structure on palms, bromeliads and bamboos in Atlantic Forest fragments of Northeastern Brazil / Efeitos do clima e da estrutura da vegetação em palmeiras, bromélias e bambus em fragmentos de Mata Atlântica no nordeste brasileiro

Abstract Palms, bromeliads and bamboos are key elements of tropical forests and understanding the effects of climate, anthropogenic pressure and forest structure on these groups is crucial to forecast structural changes in tropical forests. Therefore, we investigated the effects of these factors on the abundance of these groups in 22 Atlantic forest fragments of Northeastern Brazil. Abundance of bromeliads and bamboos were assessed through indexes. Palms were counted within a radius of 20 m. We also obtained measures of vegetation structure, fragment size, annual precipitation, precipitation seasonality and human population density. We tested the effects of these predictors on plant groups using path analysis. Palm abundance was higher in taller forests with larger trees, closed canopy and sparse understory, which may be a result of the presence of seed dispersers and specific attributes of local palm species. Bromeliads were negatively affected by both annual precipitation and precipitation seasonality, what may reflect adaptations of these plants to use water efficiently, but also the need to capture water in a regular basis. Bamboos were not related to any predictor variable. As climate and forest structure affected the abundance of bromeliads and palms, human-induced climatic changes and disturbances in forest structure may modify the abundance of these groups. In addition, soil properties and direct measurements of human disturbance should be used in future studies in order to improve the predictability of models about plant groups in Northeastern Atlantic Forest.

Resumo Palmeiras, bromélias e bambus são importantes elementos das florestas tropicais e, entender os efeitos do clima, pressão antrópica e estrutura da floresta nesses grupos é crucial para prever alterações estruturais em florestas tropicais. Portanto, nós investigamos os efeitos desses fatores na abundância desses grupos vegetais em 22 fragmentos de Mata Atlântica no nordeste brasileiro. Abundâncias de bromélias e bambus foram registradas através de índices. Palmeiras foram contadas em um raio de 20 m. Nós também obtemos medidas da estrutura da vegetação, tamanho de fragmento, precipitação anual, sazonalidade na precipitação e densidade populacional humana. Nós testamos os efeitos desses preditores nos grupos vegetais através de análises de caminhos. A abundância de palmeiras foi maior em florestas mais altas, com árvores mais grossas, dossel fechado e sub-bosque aberto, o que deve refletir a presença de dispersores de sementes e atributos específicos das espécies de palmeiras locais. Bromélias foram negativamente afetadas pela precipitação anual e pela sazonalidade na precipitação, o que deve refletir adaptações dessas plantas para o uso eficiente da água, mas também a necessidade de captar água regularmente. Bambus não estiveram relacionados com nenhum dos preditores avaliados. Dado que clima e estrutura florestal afetaram a abundância de bromélias e palmeiras, as mudanças climáticas e distúrbios na estrutura das matas causados por ações antrópicas podem alterar a abundância desses grupos. Adicionalmente, propriedades do solo e medidas diretas de distúrbios antrópicos devem ser usadas em estudos futuros para melhorar o poder preditivo dos modelos sobre a abundância de plantas na Mata Atlântica do nordeste brasileiro.

Effects of climate and forest structure on palms, bromeliads and bamboos in Atlantic Forest fragments of Northeastern Brazil.

Palms, bromeliads and bamboos are key elements of tropical forests and understanding the effects of climate, anthropogenic pressure and forest structure on these groups is crucial to forecast structural changes in tropical forests. Therefore, we investigated the effects of these factors on the abundance of these groups in 22 Atlantic forest fragments of Northeastern Brazil. Abundance of bromeliads and bamboos were assessed through indexes. Palms were counted within a radius of 20 m. We also obtained measures of vegetation structure, fragment size, annual precipitation, precipitation seasonality and human population density. We tested the effects of these predictors on plant groups using path analysis. Palm abundance was higher in taller forests with larger trees, closed canopy and sparse understory, which may be a result of the presence of seed dispersers and specific attributes of local palm species. Bromeliads were negatively affected by both annual precipitation and precipitation seasonality, what may reflect adaptations of these plants to use water efficiently, but also the need to capture water in a regular basis. Bamboos were not related to any predictor variable. As climate and forest structure affected the abundance of bromeliads and palms, human-induced climatic changes and disturbances in forest structure may modify the abundance of these groups. In addition, soil properties and direct measurements of human disturbance should be used in future studies in order to improve the predictability of models about plant groups in Northeastern Atlantic Forest.

Selection of a suitable plant for phytoremediation in mining artisanal zones.

A study was undertaken with the aim of identifying a suitable plant for the phytoremediation of metal-polluted soil from an artisanal mining area in Ecuador. Three zones including a natural zone (NZ), abandoned zone (AZ) and intensively mined zone (IZ) were selected. Three common native plants grown in the three zones were identified and collected, including Miconia zamorensis, Axonopus compressus and Erato polymnioides. The percentage of arbuscular mycorrhizal colonization that benefits their own survival in polluted soil was analyzed in the root samples of these candidate species. Analysis of the soils and plants collected from the different zones showed that the concentrations of Pb, Zn, Cu and Cd were comparatively lower in the NZ, higher in the AZ and IZ, and highest in the AZ for all the metals. The concentration of all these metals in plant tissues was the highest in E. polymnioides. The data analysis including the metal accumulation index, bioconcentration factor and translocation factor strongly identified E. polymnioides as a hyperaccumulator plant suitable for phytoremediation.

Inter-site variation in allometry and wood density of Goupia glabra Aubl. in Amazonia.

The present study aims to compare the allometry and wood density of Goupia glabra Aubl. (Goupiaceae) in two different terra-firme sites in Amazonian forest. A total of 65 trees ≥ 10 cm DBH was sampled in both sites, with 39 trees in Nova Olinda do Norte (NOlinda, near the Amazon River) and 29 trees in Apuí (near the southern edge of the Amazon forest). Except for the relationship between DBH (diameter at breast height) and Ht (total height), allometric relationships for G.glabra differed significantly between sites. Apuí had lower intercept and greater slope for log10 (DBH) versus log10 (Hs - stem height), and, conversely, greater intercept and lower slope for log10 (DBH) versus log10 (Ch - crown height). The slope differed significantly between the sites for DBH versus Cd (crown diameter), with greater slope found for NOlinda. Mean basic wood density in Apuí was 8.8% lower than in NOlinda. Our findings highlight the variation in adaptive strategy of G. glabra due to environmental differences between sites. This is probably because of different canopy-understory light gradients, which result in differentiation of resource allocation between vertical and horizontal growth, which, in turn, affects mechanical support related to wood density. We also hypothesize that differences in soil fertility and disturbance regimes between sites may act concomitantly with light.

Inter-site variation in allometry and wood density of Goupia glabra Aubl. in Amazonia / Variação entre-sítios na alometria e densidade da madeira de Goupia glabra Aubl. na Amazônia

Abstract The present study aims to compare the allometry and wood density of Goupia glabra Aubl. (Goupiaceae) in two different terra-firme sites in Amazonian forest. A total of 65 trees 10 cm DBH was sampled in both sites, with 39 trees in Nova Olinda do Norte (NOlinda, near the Amazon River) and 29 trees in Apuí (near the southern edge of the Amazon forest). Except for the relationship between DBH (diameter at breast height) and Ht (total height), allometric relationships for G.glabra differed significantly between sites. Apuí had lower intercept and greater slope for log10 (DBH) versus log10 (Hs stem height), and, conversely, greater intercept and lower slope for log10 (DBH) versus log10 (Ch crown height). The slope differed significantly between the sites for DBH versus Cd (crown diameter), with greater slope found for NOlinda. Mean basic wood density in Apuí was 8.8% lower than in NOlinda. Our findings highlight the variation in adaptive strategy of G. glabra due to environmental differences between sites. This is probably because of different canopy-understory light gradients, which result in differentiation of resource allocation between vertical and horizontal growth, which, in turn, affects mechanical support related to wood density. We also hypothesize that differences in soil fertility and disturbance regimes between sites may act concomitantly with light.(AU)

Resumo O presente estudo tem como objetivo comparar a alometria e a densidade da madeira de Goupia glabra em dois diferentes sítios de floresta de terra firme na Amazonia. Um total de 65 árvores com DAP 10 cm foi amostrado em ambos os sítios, sendo 39 árvores em Nova Olinda do Norte (NOlinda, próximo ao rio Amazonas) e 29 em Apuí (próximo à borda sul da Amazônia). Exceto para a relação entre o DBH (diâmetro a altura do peito) e a Ht (altura total), as relações alométricas para G. glabra diferiu significativamente entre os sítios. Apuí apresentou menor intercepto e maior inclinação para a relação log10 (DBH) versus log10 (Hs altura do fuste) e, ao contrário, maior intercepto e menor inclinação para log10 (DBH) versus log10 (Ch altura da copa). A inclinação diferiu significativamente entre os sítios para DBH versus Cd (diâmetro da copa), com maior inclinação encontrada para NOlinda. A densidade básica média da madeira in Apuí foi 8.8% menor do que em NOlinda. Os resultados deste estudo destacam a variação na estratégia adaptativa de G. glabra devido às diferenças ambientais entre os sítios. Isto é provavelmente consequência dos diferentes gradientes de luz o que resulta na diferenciação na alocação de recursos entre o crescimento vertical e horizontal o que, por sua vez, afeta o suporte mecânico relacionado à densidade da madeira. Nós também levantamos a hipótese de que as diferenças em termos de fertilidade e regimes de distúrbios entre os sítios podem agir concomitantemente com o regime de luz.(AU)

Inter-site variation in allometry and wood density of Goupia glabra Aubl. in Amazonia / Variação entre-sítios na alometria e densidade da madeira de Goupia glabra Aubl. na Amazônia

Abstract The present study aims to compare the allometry and wood density of Goupia glabra Aubl. (Goupiaceae) in two different terra-firme sites in Amazonian forest. A total of 65 trees ≥ 10 cm DBH was sampled in both sites, with 39 trees in Nova Olinda do Norte (NOlinda, near the Amazon River) and 29 trees in Apuí (near the southern edge of the Amazon forest). Except for the relationship between DBH (diameter at breast height) and Ht (total height), allometric relationships for G.glabra differed significantly between sites. Apuí had lower intercept and greater slope for log10 (DBH) versus log10 (Hs – stem height), and, conversely, greater intercept and lower slope for log10 (DBH) versus log10 (Ch – crown height). The slope differed significantly between the sites for DBH versus Cd (crown diameter), with greater slope found for NOlinda. Mean basic wood density in Apuí was 8.8% lower than in NOlinda. Our findings highlight the variation in adaptive strategy of G. glabra due to environmental differences between sites. This is probably because of different canopy-understory light gradients, which result in differentiation of resource allocation between vertical and horizontal growth, which, in turn, affects mechanical support related to wood density. We also hypothesize that differences in soil fertility and disturbance regimes between sites may act concomitantly with light.

Resumo O presente estudo tem como objetivo comparar a alometria e a densidade da madeira de Goupia glabra em dois diferentes sítios de floresta de terra firme na Amazonia. Um total de 65 árvores com DAP ≥ 10 cm foi amostrado em ambos os sítios, sendo 39 árvores em Nova Olinda do Norte (NOlinda, próximo ao rio Amazonas) e 29 em Apuí (próximo à borda sul da Amazônia). Exceto para a relação entre o DBH (diâmetro a altura do peito) e a Ht (altura total), as relações alométricas para G. glabra diferiu significativamente entre os sítios. Apuí apresentou menor intercepto e maior inclinação para a relação log10 (DBH) versus log10 (Hs – altura do fuste) e, ao contrário, maior intercepto e menor inclinação para log10 (DBH) versus log10 (Ch – altura da copa). A inclinação diferiu significativamente entre os sítios para DBH versus Cd (diâmetro da copa), com maior inclinação encontrada para NOlinda. A densidade básica média da madeira in Apuí foi 8.8% menor do que em NOlinda. Os resultados deste estudo destacam a variação na estratégia adaptativa de G. glabra devido às diferenças ambientais entre os sítios. Isto é provavelmente consequência dos diferentes gradientes de luz o que resulta na diferenciação na alocação de recursos entre o crescimento vertical e horizontal o que, por sua vez, afeta o suporte mecânico relacionado à densidade da madeira. Nós também levantamos a hipótese de que as diferenças em termos de fertilidade e regimes de distúrbios entre os sítios podem agir concomitantemente com o regime de luz.

Inter-site variation in allometry and wood density of Goupia glabra Aubl. in Amazonia

Abstract The present study aims to compare the allometry and wood density of Goupia glabra Aubl. (Goupiaceae) in two different terra-firme sites in Amazonian forest. A total of 65 trees 10 cm DBH was sampled in both sites, with 39 trees in Nova Olinda do Norte (NOlinda, near the Amazon River) and 29 trees in Apuí (near the southern edge of the Amazon forest). Except for the relationship between DBH (diameter at breast height) and Ht (total height), allometric relationships for G.glabra differed significantly between sites. Apuí had lower intercept and greater slope for log10 (DBH) versus log10 (Hs stem height), and, conversely, greater intercept and lower slope for log10 (DBH) versus log10 (Ch crown height). The slope differed significantly between the sites for DBH versus Cd (crown diameter), with greater slope found for NOlinda. Mean basic wood density in Apuí was 8.8% lower than in NOlinda. Our findings highlight the variation in adaptive strategy of G. glabra due to environmental differences between sites. This is probably because of different canopy-understory light gradients, which result in differentiation of resource allocation between vertical and horizontal growth, which, in turn, affects mechanical support related to wood density. We also hypothesize that differences in soil fertility and disturbance regimes between sites may act concomitantly with light.

Resumo O presente estudo tem como objetivo comparar a alometria e a densidade da madeira de Goupia glabra em dois diferentes sítios de floresta de terra firme na Amazonia. Um total de 65 árvores com DAP 10 cm foi amostrado em ambos os sítios, sendo 39 árvores em Nova Olinda do Norte (NOlinda, próximo ao rio Amazonas) e 29 em Apuí (próximo à borda sul da Amazônia). Exceto para a relação entre o DBH (diâmetro a altura do peito) e a Ht (altura total), as relações alométricas para G. glabra diferiu significativamente entre os sítios. Apuí apresentou menor intercepto e maior inclinação para a relação log10 (DBH) versus log10 (Hs altura do fuste) e, ao contrário, maior intercepto e menor inclinação para log10 (DBH) versus log10 (Ch altura da copa). A inclinação diferiu significativamente entre os sítios para DBH versus Cd (diâmetro da copa), com maior inclinação encontrada para NOlinda. A densidade básica média da madeira in Apuí foi 8.8% menor do que em NOlinda. Os resultados deste estudo destacam a variação na estratégia adaptativa de G. glabra devido às diferenças ambientais entre os sítios. Isto é provavelmente consequência dos diferentes gradientes de luz o que resulta na diferenciação na alocação de recursos entre o crescimento vertical e horizontal o que, por sua vez, afeta o suporte mecânico relacionado à densidade da madeira. Nós também levantamos a hipótese de que as diferenças em termos de fertilidade e regimes de distúrbios entre os sítios podem agir concomitantemente com o regime de luz.

Performance of Azolla caroliniana Willd. and Salvinia auriculata Aubl. on fish farming effluent.

The increasing release of untreated fish farming effluents into water courses that flow to the Pantanal wetlands in Mato Grosso (Brazil) may drive this ecosystem to eutrophication. Therefore, the growth of Azolla caroliniana Willd. and Salvinia auriculata Aubl. in fish farming effluent and their effect on its quality were evaluated for 48 days in a greenhouse. The results were compared to those obtained in a nutrient rich solution (Hoagland ½ medium). Azolla caroliniana showed lower relative growth rate in fish farming effluent (0.020 d-1) than in Hoagland ½ medium (0.029 d-1). However, S. auriculata grew slightly better in fish farming effluent (0.030 d-1) than in Hoagland ½ medium (0.025 d-1). The species apparently contributed to reduce nitrate and phosphate concentration in Hoagland ½ medium. However, in fish farming effluent, only electrical conductivity and pH were reduced by plants compared to the control without plants. Thus, A. caroliniana and S. auriculata show low potential for improving effluent quality.