ABSTRACT Agroforestry systems have the potential to increase soil organic matter, with effects on soil carbon and nitrogen contents, but information on the application of these systems in semi-arid ...regions is still scarce. This study aimed to analyze soil carbon and nitrogen stocks in the conversion of native forest from the Caatinga Biome into integrated agriculture systems in the Brazilian semi-arid region. We evaluated the following management systems in the Haplic Inceptisol (Cambissolo Háplico eutrófico): (1) Intercropping area, cultivated with corn and Massai grass; (2) Caatinga (natural vegetation); (3) AFS10: agroforestry system with native woody forest rows occupying 33 % and agriculture occupying 66 % of the total area; and (4) AFS20: agroforestry system presenting inverse proportions of AFS10. The agroforestry systems were intercropped with sorghum or millet, pigeon pea and Massai grass. We collected disturbed and undisturbed soil samples at the layers of 0.00-0.10; 0.10-0.20; 0.20-0.40, 0.40-0.60 and 0.60-1.00 m for analysis of carbon (SOC), nitrogen (N), soil bulk density, and calculation of SOC and N stocks and C/N ratio, two years after the conversion of natural vegetation to the agricultural area (intercropping) and agroforestry system (AFS10 and AFS20). We applied principal component and cluster analysis to explore the data, and confidence interval to compare the means of accumulated SOC and N stocks up to 1 m soil depth. No differences exist for the properties analysed in superficial layers (0.00-0.10 and 0.10-0.20 m), regardless of land-use systems. AFS20 increase the SOC content and, consequently, SOC stock, in subsurface layers; on the other hand, intercropping increases N content and N stock. AFS20 presented higher accumulated SOC stocks up to 1.00 m (114.97 Mg ha-1). Agroforestry systems management is an alternative for increasing carbon sequestration under the conversion from Caatinga to agricultural areas.
ABSTRACT Recent researches have shown promising results for the use of orbital data using the Normalized Difference Vegetation Index (NDVI) to monitor and predict soybean grain yield. The objective ...of this work was to evaluate propositions of multiple linear regression models to predict soybean grain yield using NDVI. The research was carried out at the Celeiro Farm, in Monte Alegre do Piauí, PI, Brazil, in an area of 200 ha. Five images were collected during the soybean crop cycle: one from the Landsat 8 and four from the Sentinel 2. Regression analyses were carried out between grain yield data (predicted variable) extracted from harvest maps and spectral data (predictor variables) from NDVI of soybean crops at different developmental stages. The promising models were selected by the Akaike Information Criterion (AIC). The models were validated using Root Mean Square Error (RMSE) and Normalized Root Mean Square Error (nRMSE), considering the mean of soybean yield of the plot. The linear regression models developed with NDVI for the V5-V6 and R2 developmental stages showed promising results for the prediction of soybean grain yield, with mean error of predictions of 153.9 kg ha-1, representing 4.2% when compared to the data from field measures.
RESUMO Pesquisas recentes apontam resultados promissores da integração de dados orbitais utilizando o índice de vegetação NDVI, para monitorar e estimar a produtividade da soja. O objetivo do trabalho foi avaliar a proposição de modelos de regressão linear múltipla para estimativa da produtividade de grãos com uso do índice NDVI. A pesquisa foi realizada na Fazenda Celeiro, município de Monte Alegre do Piauí, PI, sendo a área de estudo de 200 ha. Foram utilizadas cinco imagens durante o ciclo de cultivo da soja, sendo uma do Landsat 8 e quatro do Sentinel 2. Efetuou-se análises de regressão entre dados de produtividade de grãos (variável predita), extraídos dos mapas de colheita, e dados espectrais de (variáveis preditoras) oriundos dos índices de vegetação (NDVI) de diferentes estádios de desenvolvimento da soja. A seleção dos modelos promissores foi efetuada pelo critério de informação de Akaike (AIC). Para validação dos modelos utilizou-se a raiz quadrada do erro quadrado médio (RMSE) e a raiz quadrada do erro quadrado médio normalizado (nRMSE) pela média da produtividade da soja no talhão. O modelo de regressão linear gerado com o índice de vegetação NDVI nos estádios de desenvolvimento V5-V6 e R2, mostrou-se promissor na predição da produtividade de grãos de soja, com erro médio de estimativa da ordem de 153,9 kg ha-1, o que representa 4,2% em relação aos dados medidos em campo.
•Characterization of honey by the stingless bees produced in the semi-arid region of the Brazilian northeast.•Concentration of carboxylic acids and physic-chemistry parameters were used in the ...evaluation.•Analysis of principal components and hierarchical cluster analysis was performed.
The physicochemical characteristics of honey vary according to bee species, climate, region, period of collection, processing and storage. In this context, this work aimed to perform a comparative study of the physicochemical characteristics of Melipona subnitida and M. fasciculata honey collected at different periods and regions of the State of Piauí, Brazil. Twenty-nine honey samples were collected and evaluated by principal component analysis from physicochemical analysis data. Twenty-two percent of the parameters analyzed differed between species. Evaluating the collection period, the honey of M. subnitida and M. fasciculata presented differences among themselves. The study revealed a similarity between the physicochemical parameters of the honey of the two species of bees, in addition, the time was one of the determining factors in the formation of clusters.
Forest ecotones show a great floristic diversity, but anthropogenic disturbances may imply in their vegetation structure reduce. This study aimed to evaluate the understory diversity of an urban and ...nonurban forests in Maranhão state. We tested the following hypotheses: 1) the understory of the non-urban forest has greater richness and diversity; 2) the spatial distribution of diversity in the non-urban understory has weak spatial dependence. The study was carried out in the São Luís (urban area) and São José de Ribamar (nonurban area) cities. Thirty plots (25m
2
) were allocated in each area and the all tree individuals up to 2 m in height were measured. Density, frequency, importance value, cover value, Shannon index (H’), and Pielou index (J’) were calculated. The Mann–Whitney test, non-metric multidimensional scaling, and Hutcheson t-test were used to analyze if there were any stastical difference between the richness, density, and diversity of both areas. We used the ordinary kriging in order to visualize the variation in richness and diversity of the vegetation. There was a difference in the floristic composition and density of each species in the two areas; the richness and diversity were significantly greater in the nonurban area. Weak spatial dependence was found in the urban area, suggesting de-characterization the fragment. The presence of urbanization in the ecotonal forest fragment has reduced the richness, diversity and spatial dependence of the understory. The diversity is high even with the changes caused by urbanization, due to the ecotonal nature of the fragments sampled.
The aim of the study was to analyze the use of Complementary Integrative Practices (PICS) and psychological counseling in the treatment of mental health in post-COVID-19 patients. Clinical, ...interventional and qualitative-quantitative case study, with 15 patients divided into G1 (Acupuncture + myofascial release) and G2 (Laserpuncture + myofascial release), submitted to 12 sessions and psychological follow-up (Group therapy + 4 sessions of individualized psychotherapy) evaluated before and after treatment regarding emotional states (DASS-21). The female sex was prevalent in the studied population, in the age group of 25 to 29 years in G1 (28.57%) and 50 to 54 years in G2 (37.50%), higher education level, with comorbidities, predominance of married in G1 and single in G2. There was a statistically significant difference (p≤0.01) in the three DASS-21 subscales before and after treatments with G1 and G2, with no statistical difference between groups. There was an association between marital status and affective-emotional states, before the treatments, married people were associated with milder levels of stress, anxiety and depression, while single/divorced people had extremely severe levels. After the treatments, the married/divorced ones had levels close to normal, while the single ones reduced the levels to mild to moderate. It is concluded that the PICS associated with psychological follow-up had a positive impact on mental health in post-COVID-19 patients.
Gypsum plays a prominent role in agriculture, being considered an effective alternative to alleviate subsurface acidity due to its higher solubility and containing sulfur. However, another ...significant aspect is which pose long-term risks of groundwater contamination due to excessive applications of salts, pesticides, and other chemicals that will be leached, or even soil chemical depletion. So far, no study has focused on understanding the impacts of the atmospheric gypsum plume originating from gibbsite mining and processing on the leaching of soil bases and chemical degradation surrounding these sites. In this study, we evaluated the behavior of chemical characteristics in soil profiles distributed along the dispersion of the atmospheric plume and in areas without interference from the industrial sector in the state of Maranhão, Northeast Brazil. Fifty-three sampling points were collected at 7 locations based on the dispersion of the dust plume through wind drift. Each sampling point was represented by three composite soil samples at depths of 0.0–0.20, 0.40–0.60, and 1.00–1.20 m, where the chemical soil characteristics were evaluated. The average levels of Ca, Mg, and K in the studied layers are classified as low, with minimum values below the method's detection limit, and they also show imbalance due to higher concentrations of Ca in the surface layer in areas affected by atmospheric dispersion. The sum and saturation of bases at all depths are classified as low. Higher aluminum saturation values were observed in the deeper soil layers. The gypsum dust altered the soil's chemical characteristics at the evaluated depths; therefore, it is necessary to seek means to mitigate gypsum dust release during gibbsite extraction and processing and ensure that the soils in areas near these enterprises maintain their natural characteristics.
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•We found changes in soil chemical characteristics in gypsum mining areas.•Imbalance in Ca, Mg, and K relationships in sites influenced by the gypsum plume•High SO42− content modifies base saturation and available Al concentration.•Leaching of Mg into deeper layers was observed.
O objetivo deste artigo foi analisar o equilíbrio e a distribuição de carga plantar em bailarinas clássicas. Trata-se de um estudo transversal de natureza quantitativa, com amostragem intencional, ...realizado com 10 bailarinas de escolas de balé clássico localizadas em Teresina-PI. Utilizou-se uma ficha de coleta de dados elaborada pelos autores, além de exames de baropodometria e estabilometria. Quanto aos resultados, a ocorrência de pisada normal (40%) foi igual à da pisada cava (40%), enquanto 20% da amostra apresentou pisada desemparelhada, sendo um pé plano e o outro cavo. Avaliando o apoio bipodal e comparando situações com olhos abertos e fechados, as participantes demonstraram um aumento estatisticamente significativo (p>0,05) nas variáveis estabilométricas de comprimento do trajeto e velocidade média. No apoio unipodal, observou-se um aumento significativo na superfície de contato e na velocidade média. Na análise dinâmica, em relação ao último contato do pé durante a fase de propulsão da marcha, metade das participantes apresentou maior distribuição de carga na região do hálux. Conclui-se que as bailarinas dependem mais da visão para ajustar o equilíbrio, e que a base de sustentação influencia a oscilação postural, proporcionando maior estabilidade quando ambos os pés estão no solo. A visão é uma importante fonte de informação sensorial para manter a estabilidade durante a prática do balé. A repetitividade dos movimentos, o tempo prolongado de exposição às sobrecargas impostas nas estruturas de sustentação, a posição constante na ponta dos pés e o uso de sapatilhas, levam as bailarinas a apresentar um pé mais cavo e maior distribuição de carga na região do hálux, o que pode ser uma estratégia para responder à instabilidade postural e permitir um controle mais eficaz do equilíbrio na prática do balé clássico.
Abstract This study evidenced the physicochemical composition and antioxidant activity (AA) of honeys (n = 31) and pollen (n = 25) of stingless bees species from Alagoas, Brazil. Fifteen parameters ...were studied under the light of a multivariate analysis. A dendrogram with three groups of honeys was stablished for the different bees, being the group III formed exclusively by samples from genus Melipona. Plebeia sp. and Tetragona clavipes Fabricius (1804) produced honeys with higher pH/acidity, electrical conductivity, phenolic total and AA. Even different bees from the same meliponary, as M. asilvai and T. clavipes, produced honeys with different AA and chemical profiles, possibly due their different nectar preference. The multivariate analysis of the bee pollen samples also showed three principal components responsible for 74.52% of their variability, clustering nine groups strongly influenced by total phenolics and AA. Honey and pollen produced by T. clavipes had the highest phenolic content and AA. Therefore, the chemical characteristics and AA of the Meliponini honey and bee pollen showed here can give support to the market to influence their incorporation in the human diet as sources of potential functional foods.
A ocorrência do besouro da cana-de-açúcar, Sphenophorus levis Vaurie, é importante em algumas regiões do Brasil. O dano é causado pelas larvas que perfuram os colmos, ocasionando perdas de até 30 ton .../ha/ano. Várias alternativas de controle têm sido utilizadas, embora nenhuma delas com resultados satisfatórios, à exceção do uso de iscas tóxicas. Sendo assim, há necessidade de otimizar sua eficiência ou propor novas técnicas. O objetivo do presente estudo foi avaliar a atratividade dos adultos de S. levis a toletes de cana e casca de abacaxi por meio de olfatômetro em "Y". Os entrenós foram tratados com melaço a 10% e foram testados depois de diferentes tempos de fermentação (24, 48 e 72h), em diferentes horários (diurno e noturno) para ambos os sexos. Os testes foram conduzidos na tentativa de relacionar a resposta de S. levis ao acetato de etila e etanol produzidos pela fermentação. A produção de ambos compostos foi determinada por cromatografia gasosa de massa (GC-MS). Os dados obtidos indicaram que os entrenós da cana-de-açúcar misturados com melaço a 10% e fermentados por 24h e 48h foram os mais atrativos a S. levis (acima de 90%). A casca de abacaxi só atraiu 62,5% dos insetos testados. A resposta olfativa foi maior durante o dia e não houve diferenças entre os sexos. A produção de etanol em todos os substratos foi maior do que a do acetato de etila, embora não tenha sido possível estabelecer uma relação clara com a resposta dos insetos às iscas.
The occurrence of the sugarcane weevil Sphenophorus levis Vaurie is important in sugarcane in some regions in Brazil. Damage is caused by the larvae as they bore into the nodes and can reach 30 ton/ha/year. Many control alternatives have been attempted, but none were satisfactory, except for the use of toxic baits. Therefore, it is necessary to optimize their efficiency or to propose new techniques. The objective of the current study was to evaluate the attractiveness of adults of S. levis to sugarcane nodes and pineapple peelings in an "Y" tube olfactometer. The sugarcane internodes were treated with 10% molasses, and tested after different periods of fermentation (24, 48 e 72h), at different times of the day (diurnal and nocturnal) and with both sexes. These tests were carried out in order to correlate the response of S. levis to ethyl acetate and ethanol release as a result of the fermentation process. The release of both compounds was monitored by gas chromatography-mass spectrometry (GC-MS). Our data indicated that sugarcane internodes mixed with 10% molasses fermented for 24h and 48h were the most attractive to S. levis (up to 90%). Pineapple peelings attracted 62.5% of the tested insects. The olfactory response was higher during the day, and no differences were found between the sexes. The production of ethanol in all plant substrates was higher than ethyl acetate, but we could not establish a clear correlation with the insect response to baits.
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