In addition to the largest existing expanse of tropical forests, the Brazilian Amazon has among the largest area of mangroves in the world. While recognized as important global carbon sinks that, when disturbed, are significant sources of greenhouse gases, no studies have quantified the carbon stocks of these vast mangrove forests. In this paper, we quantified total ecosystem carbon stocks of mangroves and salt marshes east of the mouth of the Amazon River, Brazil. Mean ecosystem carbon stocks of the salt marshes were 257 Mg C ha while those of mangroves ranged from 361 to 746 Mg C ha Although aboveground mass was high relative to many other mangrove forests (145 Mg C ha), soil carbon stocks were relatively low (340 Mg C ha). Low soil carbon stocks may be related to coarse textured soils coupled with a high tidal range. Nevertheless, the carbon stocks of the Amazon mangroves were over twice those of upland evergreen forests and almost 10-fold those of tropical dry forests.

The search for tools to perform soil surveying faster and cheaper has led to the development of technological innovations such as remote sensing (RS) and the so-called spectral libraries in recent years. However, there are no studies which collate all the RS background to demonstrate how to use this technology for soil classification. The present study aims to describe a simple method of how to classify soils by the morphology of spectra associated with a quantitative view (400-2,500 nm). For this, we constructed three spectral libraries: (i) one for quantitative model performance; (ii) a second to function as the spectral patterns; and (iii) a third to serve as a validation stage. All samples had their chemical and granulometric attributes determined by laboratory analysis and prediction models were created based on soil spectra. The system is based on seven steps summarized as follows: i) interpretation of the spectral curve intensity; ii) observation of the general shape of curves; iii) evaluation of absorption features; iv) comparison of spectral curves between the same profile horizons; v) quantification of soil attributes by spectral library models; vi) comparison of a pre-existent spectral library with unknown profile spectra; vii) most probable soil classification. A soil cannot be classified from one spectral curve alone. The behavior between the horizons of a profile, however, was correlated with its classification. In fact, the validation showed 85 % accuracy between the Morphological Interpretation of Reflectance Spectrum (MIRS) method and the traditional classification, showing the importance and potential of a combination of descriptive and quantitative evaluations.

The mapping of soil attributes provides support to agricultural planning and land use monitoring, which consequently aids the improvement of soil quality and food production. Landsat 5 Thematic Mapper (TM) images are often used to estimate a given soil attribute (i.e., clay), but have the potential to model many other attributes, providing input for soil mapping applications. In this paper, we aim to evaluate a Bare Soil Composite Image (BSCI) from the state of São Paulo, Brazil, calculated from a multi-temporal dataset, and study its relationship with topsoil properties, such as soil class and geology. The method presented detects bare soil in satellite images in a time series of 16 years, based on Landsat 5 TM observations. The compilation derived a BSCI for the agricultural sites (242,000 hectare area) characterized by very complex geology. Soil properties were analyzed to calibrate prediction models using 740 soil samples (0–20 cm) collected of the area. Partial least squares regression (PLSR) based on the BSCI spectral dataset was performed to quantify soil attributes. The method identified that a single image represents 7 to 20% of bare soil while the compilation of the multi-temporal dataset increases to 53%. Clay content had the best soil attribute prediction estimates (R2 = 0.75, root mean square error (RMSE) = 89.84 g kg−1, and accuracy = 74%). Soil organic matter, cation exchange capacity and sandy soils also achieved moderate predictions. The BSCI demonstrates a strong relationship with legacy geological maps detecting variations in soils. From a single composite image, it was possible to use spectroscopy to evaluate several environmental parameters. This technique could greatly improve soil mapping and consequently aid several applications, such as land use planning, environmental monitoring, and prevention of land degradation, updating legacy surveys and digital soil mapping.

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Intestinal ischemia and reperfusion (intestinal I/R) causes acute lung inflammation that is characterized by leukocyte migration, increased lung microvascular permeability, and, in severe forms, noncardiogenic pulmonary edema and acute respiratory distress syndrome. Female sex hormones interfere with immune response, and experimental and clinical evidence shows that females are more resistant than males to organ injury caused by gut trauma. To reduce the lung inflammation caused by intestinal I/R, we have acutely treated male rats with estradiol. Intestinal I/R was performed by the clamping (45 min) of the superior mesenteric artery (SMA), followed by 2 h of intestinal reperfusion (unclamping SMA). Groups of rats received 17β estradiol (E2, 280 µg/kg, i.v., single dose) 30 min after the SMA occlusion (ischemia period) or 1 h after the unclamping of SMA (reperfusion period). Leukocytes influx into the lung and microvascular leakage were assessed by lung myeloperoxidase activity and Evans blue dye extravasation, respectively. The lung expression of adhesion molecules (intercellular adhesion molecule 1, platelet endothelial cell adhesion molecule 1, and vascular cell adhesion molecule [VCAM]) was evaluated by immunohistochemistry. Interleukin 1β (IL-1β), IL-10, and NOx concentrations were quantified in supernatants of cultured lung tissue. We have found that intestinal I/R increased the lung myeloperoxidase activity and Evans blue dye extravasation, which were reduced by treatment of rats with E2. Intestinal I/R increased ICAM-1 expression only, and it was decreased by E2 treatment. However, E2 treatment reduced the basal expression of platelet endothelial cell adhesion molecule 1. E2 treatment during intestinal ischemia was effective to reduce the levels of IL-10 and IL-1β in explant supernatant, but only IL-10 levels were reduced by E2 at reperfusion phase. The treatment with E2 did not affect NOx concentration. Taken together, our data suggest that estradiol modulates the lung inflammatory response induced by lung injury, likely by acute effects. Thus, acute estradiol treatment could be considered as a potential therapeutic agent in ischemic events.

-Minimizing environmental impacts and increasing crop productivity depend mainly on the knowledge of chemical, physical and mineralogical characteristics of the soil attributes. However, traditional methods are timeconsuming and costly. The objective of this study was to determine and validate a method to quantify soil attributes using UV-Vis-NIR Spectroscopy as an alternative to conventional methods of soil analyses. The work comprised two main phases: (1) creation and calibration of statistical models to determine the soil attributes derived from spectral data extracted from soil samples collected in area 1, (2) validation of statistical models in area 2 and correlations between the estimated and observed values (conventional method) for each soil attribute. The equations of the attributes Fe 2 O 3 , Al 2 O 3 , and clay reached R 2 > 0.80 and may be applied to a different database than the one that was used to generate the equations, provided that they belong to the same study site.Key words: Reflectance. Soil analysis. Remote Sensing.RESUMO -A minimização de impactos ambientais e o aumento da produtividade agrícola dependem, principalmente, do conhecimento de características químicas, físicas e mineralógicas do solo. Os métodos tradicionais utilizados para este fim consomem muito tempo e são de elevado custo financeiro. O objetivo deste trabalho foi o de testar e validar um método de quantificação de atributos do solo pela energia eletromagnética refletida e detectada por espectrorradiometro no visível e infravermelho. Este procedimento surge como apoio ao método convencional de análise de solo. Para sua execução, as etapas de trabalho compreenderam duas fases: (1) criação e calibração de modelos estatísticos de determinação dos atributos do solo obtidos a partir de dados espectrais (obtidos por sensor em laboratório 450-2500 nm) extraídos de amostras de terra em uma área; (2) validação dos modelos estatísticos numa outra área desconhecida e correlações entre os valores estimados e determinados (método convencional). Concluiu-se que as equações dos atributos Fe 2 O 3 , Al 2 O 3 e Argila, atingiram R 2 > 0,80 podendo ser aplicadas a uma base de dados diferente daquela que foi utilizada na geração das equações, desde que pertença a mesma região de estudo.Palavras-Chave: Reflectância. Solos-análise. Sensoriamento Remoto.

We demonstrated that intestinal IR interferes with lung homeostasis, priming the tissue to generate proinflammatory mediators for at least 24 h postischemia. Furthermore, our data confirm that the inflammatory responses caused by intestinal IR are estradiol mediated.

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