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Copyright of Ciência Florestal (01039954) is the property of Ciencia Florestal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The ecological influence of functional traits on species persistence as well as on their role over the organization of forest communities in the Brazilian Cerrado biome have not been fully understood yet. In this study, we assessed the effects of six functional groups, characterized by three seed dispersal syndromes (i.e., anemochory, autochory, and zoochory) and three wood density classes (i.e., hardwood, lightwood, and softwood), on tree spatial distribution patterns, habitat occupancy, and ecosystem services (biomass hyper dominance and abundance) provided by a forest community located in the "Parque do Lajeado", state of Tocantins, Brazil. The similarity among study sites was characterized by applying the tree dominant height approach and the environmental and soil variables as input. The floristic similarity was assessed by applying the Bray-Curtis index. The zoochoric species showed more aggregated spatial pattern at local scale, which indicates that it is more sensitive to environmental gradients than other dispersal syndromes. Meanwhile, hardwood density species were more established in the community, being more persistent to environmental filters. We observed that a small number of species contributed with about 50% of the abundance and biomass of the community, whose functional traits (wood density and dispersal syndrome) indirectly affect the relationship among the community species richness and their ecosystem functions. We observed that the functional traits related to seed dispersal and wood density functional groups resulted in different spatial distribution patterns of those tree species. Therefore, functional traits and environmental factors combined have substantially affected the structure and composition of forest communities at local scale. [ABSTRACT FROM AUTHOR]

Copyright of Ciência Florestal (01039954) is the property of Ciencia Florestal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ciência Florestal (01039954) is the property of Ciencia Florestal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Desenvolvimento e Meio Ambiente is the property of Universidade Federal do Parana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As atividades de manejo florestal são consideradas importantes para o desenvolvimento sustentável no Brasil. Tais atividades, entretanto, exigem monitoramento rigoroso que muitas vezes é de difícil operacionalização. O mapeamento das áreas afetadas pela exploração seletiva de madeira e a mensuração dos impactos decorrentes da exploração florestal ainda são dependentes de extensos e onerosos levantamentos de campo. Neste estudo foi utilizada a tecnologia Light Detection and Ranging (LiDAR) aerotransportada para avaliação dos impactos causados pela extração seletiva de madeira em 21 Unidades de Produção Anual na Amazônia. As áreas de estudo estão localizadas nos estados de Rondônia e do Pará, dentro de Florestas Nacionais sob regime de concessão florestal federal. Foram utilizadas duas métricas derivadas da nuvem de pontos LiDAR para o mapeamento dos impactos nas florestas: a Canopy Height Model (CHM) como métrica do dossel e a Relative Density Model (RDM) como métrica do sub-bosque. Os resultados da detecção dos impactos florestais obtidos do mapeamento com dados do LiDAR são compatíveis com o levantamento realizado em campo. Estimou-se que as atividades de extração seletiva de madeiras impactaram em média 6,8% (± 1,3%, desvio padrão) da área total de sub-bosque das Unidades de Produção Anual (UPA) avaliadas e causaram incremento de 4,9% ± 0,9% em área de clareiras. A tecnologia LiDAR é efetiva para o monitoramento dos impactos da extração seletiva de madeiras em áreas sob concessão florestal federal na Amazônia. [ABSTRACT FROM AUTHOR]

Selective logging is one of the leading causes of forest degradation in the Brazilian Amazon region. The Brazilian Federal government has adopted a forest concession policy as a strategy to mitigate impacts of selective logging and regulate operations of the tropical timber industry in Brazil. This study used fractional forest coverage derived from satellite imagery and field data to assess forest degradation in two selectively logged study sites within the Jamari National Forest, a protected area located in the western Brazilian state of Rondônia. Initially, we estimated the fractional coverage from vegetation indices using RapidEye imagery and compared to gap fraction data derived from hemispherical photos acquired in the field. Subsequently, we estimated the impacts of different types of selective logging activities (log decks, primary and secondary roads, tree fall gaps, and skid trails) on forest cover using the fractional coverage dataset. The NDVI showed the highest R² (0.56), indicating that 56% of the sample variation in fractional coverage derived from ground measurements can be explained by fractional coverage derived from the NDVI model. Our results also showed that the intensity of canopy impacts may vary according to the selective logging activity, ranging from skid trails to log decks which had the lightest and the heaviest canopy impacts, respectively. [ABSTRACT FROM AUTHOR]

Copyright of Ambiência is the property of Revista Ambiencia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)