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The 2020 environmental catastrophe in Pantanal has highlighted the fragility of environmental policies and practices for managing and fighting fires in this biome. Therefore, it is essential to know the causes and circumstances that potentiate these fires. This study aimed to: (I) assess the relationship between fire foci and carbon absorption (GPP), precipitation, and carbon dioxide (CO2) flux; (ii) analyze vegetation recovery using the differenced normalized burn ratio (ΔNBR) in Brazilian Pantanal between 2001 and 2022; and (iii) identify priority areas, where the highest intensities of fire foci have occurred, in order to guide public policies in Brazil to maintain local conservation. To this purpose, fire foci were detected using data from the MODIS MOD14/MYD14 algorithm, annual precipitation with CHIRPS (Climate Hazards Group InfraRed Precipitation with Station data), and CO2 flux using the MODIS/MODO9A1 product, and Gross Primary Production (GPP) with the MODIS/MOD17A2 product. The severity of the burned area was also assessed using the ΔNBR index and the risk areas were determined using the averages of these images. During the time series studied, a total of 300,127 fire foci were detected throughout the Pantanal, where 2020 had the highest number of foci and the lowest accumulated precipitation. The years with the highest precipitation were 2014 and 2018. The year 2018 was also the second year with the highest GPP value. The Pettit test showed a trend for 2008 and 2011 as the points of change in the CO2 flux and GPP variables. Principal component analysis clustered fire foci and precipitation on opposite sides, as well as GPP and CO2 flux, while ΔNBR clustered HS, MHS and MLS classes with the years 2020, 2019, 2002 and 2021. There was a high negative correlation between fire foci × rainfall and GPP × CO2 flux. The years with the largest areas of High severity (HS), Moderate-high severity (MHS) and Moderate-low severity (MLS) classes were 2020 and 2019, respectively. The most vulnerable areas for severe fires were the municipalities of Cáceres, Poconé, and Corumbá. The major fire catastrophe in 2020 is correlated with the low precipitation in 2019, the high precipitation in 2018, and the increased GPP, as well government policies unfavorable to the environment.

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The growth of the world population has led to the expansion of agricultural areas to produce food that meets world demand, making it necessary to increase productivity and maintain environmental sustainability in these areas. Seeking sustainable food production, the agricultural use of soil must be assessed in view of optimal use or land as natural resource, as well as minimize the effects of global warming related to land use and land cover (LULC). We hypothesize that different LULC affects Amazonian soil attributes. In this study, the effect of different LULC in the southern Brazilian Amazon, namely, native forest, pasture, and rice and soybean crops, on the spatial variability of soil fertility and texture was assessed, seeking to obtain information that will guide farmers in the near future to better exploit their areas and contribute to a more sustainable agriculture. Descriptive statistical analysis was performed for the pH, H + Al, Al, Ca, Mg, P, K, Cu, Fe, Mn, Zn, V, m, organic matter, clay, silt, and sand values from soil samples under different LULC. To verify the data normality, the Shapiro-Wilk test at 5% significance was performed. Outlier analysis using boxplot graphics, principal component analysis (PCA), and cluster analysis was performed. Data were submitted to geostatistical analysis to verify the spatial dependence degree of the variables through semivariograms for interpolated kriging maps. Except for silt, all variables were well represented in the factor map. PCA revealed that the data variability can be explained mainly by pH, V, Ca, K, and Zn values, which are inversely proportional to m, P, and sand. Through geostatistical analysis, spatial dependence ranging from moderate to strong was observed, generating reliability in the prediction of most attributes in pasture, rice, and soybean areas. Yet, a spatial dependence ranging from moderate to strong was found, generating reliability in the prediction of most attributes in pasture, rice, and soybean areas. Our findings reveal a lower fertility and higher acidity in forest areas, whereas crop areas presented the opposite result.

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RESUMEN

The guidance on decision-making regarding deforestation in Amazonia has been efficient as a result of monitoring programs using remote sensing techniques. Thus, the objective of this study was to identify the expansion of soybean farming in disagreement with the Soy Moratorium (SoyM) in the Amazonia biome of Mato Grosso from 2008 to 2019. Deforestation data provided by two Amazonia monitoring programs were used: PRODES (Program for Calculating Deforestation in Amazonia) and ImazonGeo (Geoinformation Program on Amazonia). For the identification of soybean areas, the Perpendicular Crop Enhancement Index (PCEI) spectral model was calculated using a cloud platform. To verify areas (polygons) of largest converted forest-soybean occurrences, the Kernel Density (KD) estimator was applied. Mann-Kendall and Pettitt tests were used to identify trends over the time series. Our findings reveal that 1,387,288 ha were deforested from August 2008 to October 2019 according to PRODES data, of which 108,411 ha (7.81%) were converted into soybean. The ImazonGeo data showed 729,204 hectares deforested and 46,182 hectares (6.33%) converted into soybean areas. Based on the deforestation polygons of the two databases, the KD estimator indicated that the municipalities of Feliz Natal, Tabaporã, Nova Ubiratã, and União do Sul presented higher occurrences of soybean fields in disagreement with the SoyM. The results indicate that the PRODES system presents higher data variability and means statistically superior to ImazonGeo.

RESUMEN

There are few research involving vegetables pests, especially when we consider the culture of lettuce (Lactuca sativa). Thus, the aim of this study was to verify the presence of stinkbugs Edessa meditabunda over four cultivars of lettuce. The experiment was conducted in field conditions in the vegetable garden of farm Florentino, Novo Progresso, south Pará State (7°07'45.71"S 55°23'21.13"W), between the months october and december 2010. We used four cultivars of lettuce: Elba (curly group), Teresa (american group), Regina (smooth group), and Mimosa (clippings group). The samplings of stinkbugs were made in december, when the plants had 30 days after transplantation. In each cultivar was randomly selected one lettuce plant per line, totaling 10 plants sampled from each cultivar/day and 30 plants per cultivar during all samplings. The data were submitted to analysis of variance and the averages were compared by Tukey test at 5% probability. Were collected 443 adults, 127 nymphs and 50 postures of E. meditabunda.The results shows that the incidence of adults was higher in cultivars Elba (curly group) and Teresa(american group) (p<0,001) and the abundance of nymphs and postures of E. meditabunda were statistically higher in the cultivar Elba (curly group) than others cultivars (p<0,001), indicating the preference of stinkbugs for these cultivars. Considering the few studies conducted with E. meditabunda, and this being the first to obtain information about the occurrence of stinkbugs attacking different cultivars of lettuce, we suggest further studies to evaluate the physiological and morphological effects caused by these insects in lettuce.

Pesquisas envolvendo pragas de hortaliças são escassas, principalmente quando consideramos a cultura da alface. Assim, este estudo teve como objetivo avaliar a presença de percevejos Edessa meditabundaF.em quatro cultivares de alface. O experimento foi conduzido em condições de campo, na horta da Fazenda Florentino, município de Novo Progresso, sul do Estado do Pará, Brasil (7°07'45.71"S 55°23'21.13"W), entre os meses de outubro e dezembro de 2010. Foramutilizadas quatro cultivares de alface, sendo elas: Elba (do grupo crespa), Teresa (do grupo americana), Regina (do grupo lisa) e Mimosa (do grupo repicada). As coletas de percevejos foram realizadas em dezembro, quando as plantas já apresentavam 30 dias de transplante. Em cada cultivar foi sorteado uma planta de alface por linha, totalizando 10 plantas amostradas em cada cultivar/dia e 30 plantas por cultivar durante todas as coletas. Os dados foram submetidos à análise de variância e as médias comparadas pelo teste de Tukey a 5% de probabilidade. Foram coletados 443 adultos, 127 ninfas e 50 posturas de E. meditabunda. Os resultados mostram que a incidência de adultos foi maior nas cultivares Elba (crespa) e Teresa (americana) (p<0,001) e que a abundância de ninfas e posturas de E. meditabunda foram maiores na cultivar Elba (crespa) quando comparados com as outras cultivares (p<0,001), indicando a preferência dos percevejos por estas cultivares. Considerando a escassez de trabalhos sobre E. meditabundaem alface, e sendo este o primeiro a obter informações sobre a ocorrência deste percevejo em diferentes cultivares, fica como sugestão para posteriores estudos, analisar os efeitos fisiológicos e morfológicos que E. meditabunda causa sobre as diferentes cultivares de alface.

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