This work compares methods of climate measurements, such as those used to measure evapotranspiration, precipitation, net radiation, and temperature. The satellite products used were compared and evaluated against flux tower data. Evapotranspiration was validated against the SSEBop monthly and GLEAM daily and monthly products, respectively, and the results were RMSE = 24.144 mm/month, NRMSE = 0.223, r² = 0.163, slope = 0.411; RMSE = 1.781 mm/day, NRMSE = 0.599, r² = 0.000, slope = 0.006; RMSE = 36.17 mm/month, NRMSE = 0.401, r² = 0.002, and slope = 0.026. Precipitation was compared with the CHIRPS data, K67 was not part of the CHIRPS station correction. The results for both the daily and monthly comparisons were RMSE = 18.777 mm/day, NRMSE = 1.027, r² = 0.086, slope = 0.238 and RMSE = 130.713 mm/month, NRMSE = 0.706, r² = 0.402, and slope = 0.818. The net radiation validated monthly with CERES was RMSE = 75.357 W/m², NRMSE = 0.383, r² = 0.422, and slope = 0.867. The temperature results, as compared to MOD11C3, were RMSE = 2.829 °C, NRMSE = 0.116, r² = 0.153, and slope = 0.580. Comparisons between the remote sensing products and validation against the ground data were performed on a monthly basis. GLEAM and CHIRPS daily were the data sets with considerable discrepancy.

The goal of this work is to compare the main air turbulence characteristics of two common areas in the Amazonian landscape: a dense forest (rough surface) and a water surface (smooth surface). Using wind components data collected at high frequency by sonic anemometers located just above these surfaces, turbulence intensity and power spectra, temporal and length scales of the eddies, as well as the main terms of the $\mathrm{TKE}$ budget ($\mathrm{TKE}$ = turbulent kinetic energy) were evaluated for each surface type. The results showed that in general, the air turbulence intensity above the forest was higher than above the lake during the daytime, due to the high efficiency of the forest in absorbing the momentum of the turbulent flow. During the nighttime, the situation was reversed, with greater air turbulence intensity above the lake, except in some periods in which intermittent turbulence bursts occured above the forest.

The aim of this study was to evaluate the temporal evolution of average characteristics of the vertical profiles of speed and direction above and within of the forest canopy at the Cuieiras experimental site, located about 100 km from the Manaus, Amazonas state, Brazil. We used about 10 months of half-hourly averaged data from 10 sonic anemometers installed at different levels above and within the forest canopy during GoAmazon project in 2014. We found that the vertical wind speed profile varied with the various layers above and below the forest canopy, describing an S-shape type, a form determined by physical obstructions imposed by vertical heterogeneity of the canopy. The predominant wind directions were not constant with height, suggesting that very local circulations can influence the subcanopy flow.

Livestock systems have been identified as major emitters of greenhouse gases due to the use of extensive areas with degraded pastures. The objective of this study was to analyze carbon (CO₂) and methane (CH₄) fluxes in the atmosphere as indicators of environmental sustainability in silvopastoral systems. CO₂ and CH₄ fluxes from soil to the atmosphere were monitored in a degraded pasture (predominant species: Panicum maximum cv. Mombaça) grown in full sun and compared with areas with tree species (Bertholletia excelsa, Dipteryx odorata, and Khaya grandifoliola) and productive pasture (Panicum maximum cv. Mombaça) grown in full sun. The study area was in Mojuí dos Campos, western Pará state, Eastern Amazon, Brazil. The evaluations were conducted in a Technological Reference Unit with a silvopastoral system, where animals used the shade of trees during high-temperature periods. The fluxes were measured using an ultraportable greenhouse gas analyzer coupled with static polyvinyl chloride ring chambers installed at the soil–air interface. In conclusion, areas with integrated systems (B. excelsa + pasture and K. grandifoliola + pasture) were better mitigators of CO₂ emissions; the highest emissions occurred in the degraded pasture area during the rainiest months. The CH₄ fluxes were more intense in the areas with degraded pasture and K. grandifoliola + pasture. Converting degraded pasture areas into integrated crop–livestock–forest systems reduced greenhouse gas emissions in the Amazon over 10 years of implementation. The implementation of integrated crop–livestock–forest systems in long-deforested areas with degraded pastures and a low production capacity showed high potential for changes focused on developing sustainable agriculture in the Amazon.

In the Amazon region studies on greenhouse gases are still carried out with low frequency, so understanding the dynamics and flow of these gases in the region is of great importance. Among these gases is methane, which is the second most concentrated greenhouse gas in the atmosphere. In this context, the objective of this study was to quantify the methane fluxes in primary forest and pasture areas and analyze the seasonal variability of the emission/absorption of this gas, as well as to verify the influence of environmental factors acting on the behavior of methane. The study region was the Municipality of Belterra, Western Pará. To measure the methane fluxes in the soil, static chambers were used with the aid of a greenhouse gas analyzer (Los Gatos Research (LGR-915-0011). The methane flux in the soil in the Flona region averaged -1,499 ± 1.3 mg CH₄ m−2 d−1 and an average of -0.4776 ± 1.21 mg CH₄ m−2 d−1 for the pasture area, positive and negative values ​​were obtained for the different areas, indicating emission and consumption of methane, respectively, in the studied period.

The Hydraulic Concepts Model Distributed from Large Basins of the Hydraulic Research Institute (MGB-IPH) is a rainfall-type model validated in several basins in South America, including in rivers of the Amazon Basin. The inputs of the model are climatological, rainfall, relief and soil cover data. The objective of this study is to test the sensitivity of the model in extreme scenarios of soil use and occupation, changes in precipitation and mean air temperature. The case study was carried out in the Curuá-Una river basin, located southeast of Santarém-Pará. The MapWindow-GIS software and the IPH-Hydro Tools plug-in were used in the preprocessing, and the MGB-IPH plugin was processed. The results showed that the MGB-IPH has sensitivity to changes in soil use, precipitation and mean air temperature. In the sensitivity test of soil use and occupation the results showed that low vegetation and anthropization increase the maximum peaks of flow; In periods of Amazon flood with low rainfall occurrence, the low vegetation scenario has a higher flow rate; And the forest scenery prevents intense floods. In the tests of changes in the precipitation regime, a 50% decrease in rainfall reduced the flow by 32% and a 50% increase in rainfall increased the flow by 218.6%. However, in the tests of increase of the mean air temperature the results did not show significant responses in the flow regime, however, this scenario, added with the increase and / or decrease of the precipitation regime, presented as attenuator for both floods and droughts. Teste de sensibilidade do Modelo Hidrológico de Grandes Bacias (MGB-IPH) em cenários de mudanças extremas no uso e ocupação do solo e, regime de precipitação e temperatura média do ar R E S U M O O Modelo Hidrológico Conceitual Distribuído de Grandes Bacias do Instituto de Pesquisas Hidráulicas (MGB-IPH) é um modelo do tipo chuva-vazão validado em diversas bacias da América do Sul, inclusive, em rios da bacia amazônica. As entradas do modelo são dados climatológicos, relevo e cobertura do solo. Pretende-se neste estudo testar a sensibilidade do modelo em cenários extremos de uso e ocupação do solo e, alterações na precipitação e temperatura média do ar. O estudo de caso foi realizado na bacia do rio Curuá-Una localizado a sudeste de Santarém-Pará. No pré-processamento utilizou-se o software MapWindow-GIS e o plugin IPH-Hydro Tools e no processamento utilizou-se o plugin MGB-IPH. Os resultados mostraram que o MGB-IPH possui sensibilidade às mudanças no uso do solo, precipitação e temperatura média do ar. No teste de sensibilidade de uso e ocupação do solo os resultados mostraram que vegetação baixa e antropização aumentam os picos máximos de vazão; em períodos de cheia amazônica com ocorrência de baixa precipitação o cenário vegetação baixa possui maior vazão; e o cenário floresta evita cheias intensas. Nos testes de mudanças no regime de precipitação a diminuição de 50% de chuvas reduziu a vazão em 32% e, o aumento de 50% de chuvas aumentou a vazão em 218,6%. Já nos testes de aumento da temperatura média do ar os resultados não mostraram respostas significativas no regime de vazão, porém este cenário, somado com o aumento e/ou diminuição do regime de precipitação, se apresentou como atenuador tanto para as cheias quanto para as secas. Palavras-chave: Modelagem Hidrológica, Uso e Ocupação do Solo, Bacias hidrográficas, Testes de sensibilidade.