The replacement of the stock of trees managed area over the years is widely studied, however, the recovery of forest biogeochemical cycles is poorly understood. Thus, the study aimed to verify the level of a forest evapotranspiration Forest, to assess the influence of exploitation on forest hydrology. The study area is located in the Tapajos National Forest (TNF; 3.017 S, 54.970 N), in Para state, a conservation unit with 6 × 105 ha area of tropical rainforest, with canopy height of vegetation 40 m, approximately 70 km south of the city of Santarem. The instrument platform was installed in June 2000, approximately 7 miles west of the entrance of 83 km from Cuiabá-Santarém Highway and 14 km east of the east bank of the Rio Tapajós. The 83 km area intended for forest management had its exploration activities commenced in 2001 around the tower. At 67 km there is a stretch of micrometeorological tower in unlogged forest, which will serve as the control area in the data analysis. Evapotranspiration was calculated using the Direct Method, the models Penman-Monteith and Priestley-Taylor, which were significantly different (ANOVA) for both sites. In the comparison among the areas the Direct Method was the only one who had higher averages for the 83 km, while the others had higher averages for the 67 km. We performed analysis of surface conductance (Cs), decoupling factor (Ω), which had higher values for the 67 km and aerodynamic conductance (Ca) was higher in the 83 km, which are significantly different according to Tukey 0, 05. The impact of the Activity Management designed a canopy cover of 10% according to the intensity of exploitation. In the analysis of growth after the management tree forest has a high rate of increase, and therefore the evaporation had no abrupt changes over three years after the activity. Thus, the variation of evapotranspiration for the 83 km did not change significantly after forest management activities.
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