Computer-aided classification of successional stage in subtropical Atlantic Forest: a proposal based on fuzzy artificial intelligence.

STATEMENT OF PROBLEM: Due to the continuous variability of the forest regeneration process, patterns of indicator variables with membership in more than one successional stage may occur, making the classification of such stages a challenging and complex task. PURPOSE: This study aims at presenting a comparative analysis of artificial intelligence methods as an alternative for computer-aided classification of successional stages in subtropical Atlantic Forest. As a research hypothesis, the authors consider that a fuzzy inference system should provide the best performance due to its ability to deal with uncertainties inherent to complex processes. MATERIAL AND METHODS: The analyses were carried out using a database of the forest inventory of Santa Catarina, Southern Brazil. The data are composed of 177 sampling units of subtropical Atlantic Forest (mixed ombrophilous forest), characterized according to eighth indicator variables verified from the field by experts. This database was employed to train several machine learning methods under a tenfold cross-validation process. The overall accuracy (θ) and kappa coefficient were used to compare the performance between FIS and neural networks, classifier committees and support vector machine. Then, to verify if the classification by the FIS differed from the one performed by experts, the Kappa index and a statistical significance analysis by Pearson's [Formula: see text] test were determined. The hypotheses were verified with two-way tests at a significance level (α) 0.05, for a test power (1-ß) 0.8 and minimum expected effect size between medium (ρ = 0.3). RESULTS: Statistical significance tests confirmed the hypothesis that FIS achieved the highest performance, with θ = 98.3% and a kappa value equal to 0.93 (almost perfect agreement) and showed no significant difference ([Formula: see text] = 0.047, p = 0.976) in comparison with the classification by experts. CONCLUSIONS: The use of FIS represents a promising alternative as a tool applicable for computer-aided classification of successional stages in subtropical Atlantic Forest. PRACTICAL IMPLICATIONS: The results and conclusions should substantially impact the guidelines and decision-making process for deforestation authorizations and applicable compensation measures, which are based on the forest succession stage.

Strong floristic distinctiveness across Neotropical successional forests.

Forests that regrow naturally on abandoned fields are important for restoring biodiversity and ecosystem services, but can they also preserve the distinct regional tree floras? Using the floristic composition of 1215 early successional forests (≤20 years) in 75 human-modified landscapes across the Neotropic realm, we identified 14 distinct floristic groups, with a between-group dissimilarity of 0.97. Floristic groups were associated with location, bioregions, soil pH, temperature seasonality, and water availability. Hence, there is large continental-scale variation in the species composition of early successional forests, which is mainly associated with biogeographic and environmental factors but not with human disturbance indicators. This floristic distinctiveness is partially driven by regionally restricted species belonging to widespread genera. Early secondary forests contribute therefore to restoring and conserving the distinctiveness of bioregions across the Neotropical realm, and forest restoration initiatives should use local species to assure that these distinct floras are maintained.

Antioxidant and anti-inflammatory action (in vivo and in vitro) from the trunk barks of Cabreúva (Myrocarpus frondosus Allemao, Fabaceae).

ETHNOPHARMACOLOGICAL RELEVANCE: Myrocarpus frondosus, known as cabreúva, is a tree whose trunk barks are used in folk medicine as tea, syrup, ointments, and tinctures for the treatment of inflammation. However, there is no scientific evidence demonstrating this activity. AIM OF THE STUDY: The present investigation was focused on evaluating the antioxidant and anti-inflammatory activities of M. frondosus, using the in vitro model of RAW 264.7 macrophages induced by LPS and the in vivo model of mouse pleurisy induced by carrageenan. MATERIALS AND METHODS: M. frondosus trunk barks were dried at room temperature for seven days and subjected to exhaustive maceration with ethanol (70%) to obtain its crude extract (CE). CE was subjected to UPLC-HRMS analysis to establish its chemical profile. Its antioxidant activity was evaluated using the DPPH method, reducing power by the iron (III) to iron (II) reduction assay and the ß-carotene-linoleic acid bleaching assay. The RAW 264.7 macrophages were pretreated with the CE in a non-cytotoxic concentration and induced by LPS (1 µg/mL). After 24 h, using the supernatant, we evaluated the nitric oxide (NOx) and interleukin-6 (IL-6) levels. The anti-inflammatory effects of CE (at doses of 30, 100 and 300 mg/kg) were evaluated on leukocyte migration (total and differential), exudate concentrations, myeloperoxidase (MPO) and adenosine-deaminase (ADA) activities, NOx, tumor necrosis factor-α (TNF-α), and IL-6 levels, by using a murine model of neutrophilic inflammation. RESULTS: The UPLC-HRMS of CE revealed the presence of isoflavonones, including biochanin A and formononetin. CE exhibited good antioxidant activity by quenching and decreasing free radicals, as well as reducing pro-oxidant metals. CE did not show cytotoxicity at a concentration below 11 µg/mL and reduced the secretion of the pro-inflammatory NOx in the inflamed macrophages. In vivo assay revealed that CE caused a pronounced inhibition on leukocyte migration, and this inhibition was due to its ability to reduce neutrophil migration. Moreover, CE was also able to reduce the release of critical pro-inflammatory mediators such as MPO, NOx, TNF-α, and IL-6. CONCLUSIONS: All these findings indicate that M. frondosus exhibited antioxidant activity and anti-inflammatory effect.

Roça-de-toco: uso de recursos florestais e dinâmica da paisagem rural no litoral de Santa Catarina / Slash-and-burn agriculture: use of forest resources and dynamics of rural landscape in Santa Catarina State, Brazil

Os fragmentos florestais nas pequenas propriedades agrícolas de Santa Catarina fazem parte de um ciclo de cultivo de espécies anuais, através da agricultura de pousio (roça-de-toco). Neste estudo, procurou-se analisar o sistema de cultivo praticado pelos agricultores do município de São Pedro de Alcântara, litoral de Santa Catarina, utilizando a abordagem qualitativa. Como resultados, observou-se que em 65 por cento das propriedades houve redução da área de cultivo nos últimos 10 anos, o tempo de repouso foi reduzido e as roças passaram a ser menos itinerantes. As restrições ao uso dos recursos florestais têm promovido alterações na composição da paisagem das propriedades agrícolas da região de estudo, onde se constata uma diminuição das áreas destinadas à agricultura de pousio e um aumento crescente das áreas com formações florestais secundárias, além do aumento da proporção de formações mais avançadas no processo de sucessão natural. Entretanto, uma simulação do uso da terra revelou que é possível, do ponto de vista da disponibilidade de áreas ao longo do tempo, a continuidade do sistema de pousio, principalmente quando este destina-se à subsistência.

The secondary forests in the small farms of Santa Catarina State are traditionally used as a component of the slash-and-burn agriculture. The purpose of this study was to analyze the agricultural system in the municipality of São Pedro de Alcântara, on the coast zone of the State, using the qualitative research approach. The results showed that there was a reduction of the cultivated area in 65 percent of the farms in the last 10 years, the fallow period was reduced, and the rotation time of each field plot was shortened. The restrictions imposed by regulations on forest resources use have contributed to a change in the composition of the landscape of the study area, where a shrinkage of the area used for traditional agriculture in favor of a larger area of with secondary forests is evident. However, a simulation of the field plots rotation revealed that, from the point of view of the land availability, the continuity of the slash-and-burn agricultural system is still possible in the long run, especially under the subsistence farming.