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Aims Natural vegetation plays an important role in global carbon cycling and storage. Thus, the Cerrado (Brazilian savannah) is considered a carbon sink because of its intrinsic characteristics. Our aim was to evaluate how the aboveground biomass and biodiversity relationship change between three Cerrado remnants with different protection status: a ‘control area’ (Legal Reserve area), a protected area (PA) and a non-protected area (Non-PA). Methods All three studied fragments are situated in northern Minas Gerais state, Brazil. We estimated the aboveground carbon stocks based on the forest inventory. We also measured three dimensions of biodiversity metrics for each plot: functional trait dominance, taxonomic diversity and functional diversity. The following functional traits were evaluated for the species: wood density, maximum diameter and seed size. We carried out generalized linear models seeking to evaluate how carbon stocks, community-weighted mean (CWM) trait values, species richness and diversity, and functional diversity indices differ among the remnants. Important Findings The Cerrado areas without protection status had lower carbon stocks, species richness, species diversity, functional richness and functional dispersion, whereas both PA and Non-PA had lower CWM maximum diameter and seed size compared with the Legal Reserve control area. Generalized linear models showed that carbon stocks, species and functional richness metrics were correlated within and across sites, and thus, species richness could serve as a good proxy for functional richness and carbon stocks. The carbon stocks were positively driven by species richness and CWM maximum diameter, while they were negatively driven by functional dispersion. Functional richness, species diversity and CWM seed size appeared in the set of best models, but with no significant direct effect on carbon stocks. Thus, we concluded that absence of protection in the Cerrado areas decreases both species richness and carbon stocks.

Este estudo tem como objetivo avaliar o cenário de fragilidade ambiental do baixo Mearim através da caracterização ambiental. Esta região consiste em um ambiente estuarino que abriga uma complexa interface de ecossistemas. O avanço da salinidade proveniente do mar tem alterado drasticamente as paisagens da região. A avaliação desses impactos, passa inicialmente pela compreensão dos ecossistemas de uma forma integrada, contrapondo as abordagens que avaliam isoladamente os atributos ambientais. Para a caracterização ambiental obtiveram-se dados de geologia, geomorfologia, solos, geodiversidade, vegetação, além das séries temporais de desmatamento e queimadas para a avaliação do avanço da antropização. A análise dos resultados indicou sete formações geológicas, cinco unidades geomorfologias, sete tipos de solos, seis classes de vegetação e um relevo que abrange elevações de 0 a 318 metros em relação ao nível do mar. A partir dos resultados do avanço da antropização, o desmatamento mostrou que a série histórica foi proporcional a da área total da bacia hidrográfica; e as queimadas evidenciaram que a média da precipitação anual interfere na quantidade de focos de calor.  Desta forma, o ambiente apresenta-se frágil por ser susceptível a inundações devido à suas características topográficas levemente planas e às intervenções antrópicas, como o desmatamento e as queimadas, que facilitam a baixa proteção dos solos, sendo vulneráveis à erosão pluvial e ao escoamento.  The scenario of environmental fragility from the low course of the Mearim River A B S T R A C TThis study aims to evaluate the environmental fragility scenario of the low Mearim through the environmental characterization. This region consists of an estuarine environment that houses a complex interface of ecosystems. The advancement of salinity from the sea has drastically changed the landscape of the region. The evaluation of these impacts initially involves the understanding of the ecosystems in an integrated way, opposing the approaches that evaluate the environmental attributes alone. For the environmental characterization, geology, geomorphology, soils, geodiversity, vegetation, besides the time series of deforestation and fires were obtained for the evaluation of the advance of the anthropization. The analysis of the results indicated seven geological formations, five geomorphological units, seven types of soils, six vegetation classes and a relief that covers elevations from 0 to 318 meters in relation to sea level. The results of the advancement of anthropization, deforestation showed that the historical series was proportional to that of the total area of the river basin; and fires have shown that the average annual precipitation interferes with the amount of heat sources. As a result, the environment is fragile because it is susceptible to flooding due to its slightly flat topographic features and anthropogenic interventions, such as deforestation and fires, which facilitate low soil protection and are vulnerable to rainfall erosion and runoff.Keywords: Hydrogeology, Geotechnology, Geoprocessing.

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Background: Community composition on fragmented forest remnants has been shown to diverge from their natural successional path, revealing an alternative state which has been known as retrogressive succession. Here we show the long-term monitoring of a small forest fragment concerning community structure, species richness, functional diversity and composition throughout 17 years to offer a means to generalize community performance under the impacts of forest fragmentation. Results: The adult tree community showed shifts on its functional composition: reduction in species’ maximum height and percentage of simple leaves, indicating an investment in resource-acquisitive and disturbance adapted traits. However, we also found a gradual increase in wood density throughout the years for the adult community. For the overall community, functional composition analysis indicated a gradual reduction in the percentage of simple leaves and a significant increase in aboveground biomass. The decrease in Hmax and simple leaves, especially for the adult tree community, are mostly related do microenvironmental conditions caused by edge effects, as desiccation and tree canopy damage.Conclusion: Our results show that natural regeneration is being negatively affected, except for aboveground biomass. Although these findings could have resulted from a transient dynamic, they constitute a warning to future conservation policies around the ecological integrity of small forest fragments.