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The spatiotemporal variation of biophysical parameters in Eucalipto plantations, in the Savanna-Amazonian Mato- Grossense transition, was evaluated by means of remote sensing. The area is located in the municipality of Lucas do Rio Verde-MT, and it is composed of plots of E. urophylla, E. urograndis, native forest and exposed soil. The images were acquired on the website of the U. S. Geological Survey for the months of February 2015/16 and January 2017 (rainy season) and June 2015-2017 (dry season). The Normalized Difference Vegetation Index (NDVI), surface albedo (); surface temperature (Ts); Radiation Balance (Rn) and evapotranspiration (ET) were calculated in steps of the R-SSEB model. Eucalyptus plantations, compared to native forest, showed an increase of 3% to 4% in NDVI, Ts, Rn and ET values. Soil exposure increased albedo (69% to 109%) and Ts (14% to 34%) and reduced NDVI (63% to 58%), Rn (13% to 20%) and ET (57% to 26%), in the rainy and dry periods, respectively. It is concluded that the changes in soil use and occupation altered the biophysical parameters and evapotranspiration, being these more accentuated in deforested areas than in areas with Eucalyptus cultivation. [ABSTRACT FROM AUTHOR]

The objective this paper was to quantify the hourly variability of CO2 fluxes in the year of the El Niño, in 2015, in a tropical rain forest in the Western Amazon. Data of CO2 fluxes collected at 63.5 m height in a tower of the Large- Scale Biosphere-Atmosphere Experiment in Amazonia in the Jaru Biological Reserve, composed of the Open Ombrophilous forest, were analyzed. Data from the dry-wet period were used, which by convention, the negative and positive values indicate absorption and emission of CO2, respectively. The CO2 uptake in the forest had higher levels between 9:30 a.m. and 4:00 p.m., with mean values between -19 and -13 μmol m-2 s-1, however the peak absorption occurs at 1:00 p.m. with -30 μmol m-2 s-1, considering that at this time the sun's rays are most intense. In average, the Rebio Jaru absorbs more than the areas of the transition Amazonia-Cerrado, indicating that the physiological activities in Ombrophilous forest require a greater amount of carbon. The average daily behavior of CO2 fluxes showed higher concentrations of absorption during the day than emissions overnight, behaving as a carbon sink, corroborating the importance of the forest in assimilation of the atmospheric carbon. [ABSTRACT FROM AUTHOR]

The estimation of leaf area index (LAI) in forest ecosystems is generally performed by methods that include the intensity of electromagnetic radiation transmitted through the canopy. However, these techniques do not allow for the spatial LAI representation. Thus, the aim of this study was to evaluate the LAI of an Amazon-Cerrado transition forest estimated by data from satellite sensors. Thus, the LAI estimated by METRIC (Mapping Evapotranspiration with high Resolution and internalized Calibration) with TM - Landsat 5 imagery and the product MOD15A2 of MODIS (Moderate Resolution Imaging Spectroradiometer) was validated with local light interception measurements of a micrometeorological tower in 2008. Spatial distribution LAI were prepared for eight days considered. The LAI estimated by the MOD15A2 product agree with measurements in the field, while the METRIC was not able to produce LAI values similar to those obtained in the field. Even if the METRIC presented limitations in their use, further work is needed to parameterize your equation for a greater spatial/ temporal range data. [ABSTRACT FROM AUTHOR]

The aim of this study was to attract associations between hospitalizations for respiratory diseases and micrometeorological index in the Santarém city, located in the West Pará region in the year 2010. It was used numbers of children hospitalizations with 0-4 years old and weather data variables (relative humidity, air temperature, precipitation, atmospheric pressure). Was calculated the Micrometeorological index, through principal component analysis, were each principal component is a linear combination of all the original variables, independent of each other and estimated in proposal to retain the maximum total variation information contained in the data; To detect the association we used generalized estimating equations that are used when you want to fit models for longitudinal data. The results suggest that the greatest number of admissions occurred in June coinciding with the transition period between the rainy and dry seasons. Statistically significant associations were observed, noting that the relative risk of 10% was captured for the increase in hospitalizations due to synergy of meteorological variables. This is expected to assist in the planning of public policies and environmental health. [ABSTRACT FROM AUTHOR]

The replacement of natural forests to monoculture can cause changes in local and regional climate due to changes in net radiation and energy exchanges between the surface and the atmosphere. Thus, the objective of this study was to evaluate change s in biophysical indices such as Normalized Difference Vegetation Index (NDVI), albedo, temperature and net radiation of the surface due to the change of land cover in native Cerrado area in Campo Novo do Parecis, Mato Grosso State. We obtained Landsat 5 TM images to calculate the biophysical indices in protected and deforested areas. The NDVI of the protected area was 72% higher, the surface albedo was 56.1% lower and the surface temperature was 39.2% lower than in the deforested area. Thus, the balance of daily radiation in the protected was 6.6% higher than in the deforested area, which showed that conversion of native Cerrado area modifies the net radiation exchange between the surface and the atmosphere. [ABSTRACT FROM AUTHOR]

This study aims to analyze the microclimatic influence of a forest patch existing in the Barigui Park in Curitiba-PR. A meteorological data collection was conducted promptly for this purpose, with two Kestrel''s mini-stations, model 4200. Data of temperature, relative humidity and wind speed were collected simultaneously from a point inside the Araucaria Forest patch that belongs to the park and a mobile transect on a street adjacent to the green area. Meteorological data were collected every 50 m and the transect total length was 1000 m. The results showed statistically significant differences between the microclimate inside and outside the forest patch for all variables. Along the transect, the temperature was an average of 4.3° C higher than in the forest, reaching 6.1 ° C of maximum difference. The relative humidity inside the forest path remained constant and was on average 4.2% higher than in the street. Along the street, changes were observed in microclimatic data, probably due to the characteristics of the urban site. Thus, it can be concluded that the Barigui Park forest patch contributes to improving the microclimate of the city, providing significant impacts on the nearby areas. [ABSTRACT FROM AUTHOR]

The Pantanal is considered the largest floodplain in the world, composed of 70% for Savannah. In recent decades, due to the advancement of agriculture, much of this biome has been converted to pasture. The leaf area index (LAI) is an important measure of vegetation cover, therefore, controls the exchanges of mass and energy of a vegetated surface. Thus the objective of this study was to evaluate the estimates of LAI at a pasture in the northern Pantanal of Mato Grosso by the MODIS product (MOD15A2) and the model proposed by Allen et al. (2002) with LAI measurements obtained through the light interception and precipitation estimated by Tropical Rainfall Measuring Mission (TRMM). The study was conducted in a Brachiaria humidicola (Rendle) Schweick pasture at the Experimental Farm of the Federal University of Mato Grosso, in Santo Antônio de Leverger - MT. The data of incident, reflected and intercepted photosynthetically active radiation (PAR) in the study area were collected in a micrometeorological mast from January 2006 to February 2010. LAI was measured by the light interception method and estimated by the proposed model by Allen et al. (2002) and MODIS product. LAI measured in the pasture varied interannually and seasonally with higher values during the rainy season, reflecting the variation in rainfall. The IAF measured and estimated by Allen et al. (2002) showed no correlation with rainfall, however, the LAI estimated by MODIS product was significant correlated with precipitation. The measured LAI did not correlate with the estimated by MODIS product, but correlated with the estimated by Allen et al. (2002). The LAI values measured in the pasture and estimated by Allen et al. (2002) and the product of MODIS were significant difference through the non-parametric Kruskal Wallis test when assessed during the whole year and in each wet and dry season. The low correlation between the measured and estimated LAI in this study highlight that the estimates of LAI in grassland by remote sensing should be used with caution. [ABSTRACT FROM AUTHOR]