Tropical forests face increasing climate risk1,2, yet our ability to predict their response to climate change is limited by poor understanding of their resistance to water stress. Although xylem embolism resistance thresholds (for example, $$\varPsi $$ Ψ 50) and hydraulic safety margins (for example, HSM50) are important predictors of drought-induced mortality risk3–5, little is known about how these vary across Earth’s largest tropical forest. Here, we present a pan-Amazon, fully standardized hydraulic traits dataset and use it to assess regional variation in drought sensitivity and hydraulic trait ability to predict species distributions and long-term forest biomass accumulation. Parameters $$\varPsi $$ Ψ 50 and HSM50 vary markedly across the Amazon and are related to average long-term rainfall characteristics. Both $$\varPsi $$ Ψ 50 and HSM50 influence the biogeographical distribution of Amazon tree species. However, HSM50 was the only significant predictor of observed decadal-scale changes in forest biomass. Old-growth forests with wide HSM50 are gaining more biomass than are low HSM50 forests. We propose that this may be associated with a growth–mortality trade-off whereby trees in forests consisting of fast-growing species take greater hydraulic risks and face greater mortality risk. Moreover, in regions of more pronounced climatic change, we find evidence that forests are losing biomass, suggesting that species in these regions may be operating beyond their hydraulic limits. Continued climate change is likely to further reduce HSM50 in the Amazon6,7, with strong implications for the Amazon carbon sink.

The mining activity is highly environmental impacting, being the excavation process and waste sterile rejects crowding the main pollution sources. The Santa Catarina Coal Basin has great importance, considering that contains 4.3 billions tons of coal (13% of the Brazilian reserve) and 6.400 hectares of degraded area. That way, the study objective was to characterize and identify the ambient impacts derivated from coal mining activities, at the Sideropolis city, SC. The base method used to evaluate was The Leopold matrix which adaptations were made according to a qualitative attribute weighting matrix to verify the significance of impacts. The interaction between two actions of the enterprise and 11 generated environmental impacts was analysed according to the attributes of frequency, extension, duration, direction and degree, both in the physical and anthropic environments. All impacts had a negative direction, where the most striking activity was the opening of the cava, which, when forming the acidic lagoon, changes the surface water quality, being described as of great importance. Therefore, recognizing the principal environment problems could help on strategies to accomplish the recovery requirements of degraded areas on this area.

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RESUMO A vegetação de restinga é uma formação típica de ecossistemas costeiros de alta relevância ecológica. Dessa forma, o objetivo do estudo foi descrever a composição florística e estrutural de um fragmento de restinga herbáceo-subarbustiva localizada em Balneário Esplanada, no município de Jaguaruna, sul do Estado de Santa Catarina. Foram instaladas 20 parcelas de 4 m2 equidistantes quatro metros entre si, totalizando 80 m2 de área amostral. A cobertura de cada espécie foi estimada pela escala de Causton. Foram amostrados 90 indivíduos distribuídos em 13 famílias botânicas, 21 gêneros e 21 espécies. As famílias com maior riqueza foram Asteraceae, Poaceae, Boraginaceae e Solanaceae. As espécies mais frequentes foram Panicum racemosum e Hydrocotyle bonariensis, com VI igual a 37,5 e 23,5, respectivamente. Para a estrutura comunitária houve sete classes de altura, sendo os primeiros estratos os mais ricos e a classe 1 com o maior número de espécies. A diversidade de Shannon e equabilidade de Pielou foram 2,67 e 0,59, respectivamente.

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