Alterações micrometeorológicas causadas pelas mudanças de uso do solo no Seridó Potiguar

Abstract

The change in soil cover causes changes in the energy balance and surface water balance. Inadequate soil use can lead to an advanced degradation condition, which is called a desertification process. In Brazil, there are several Desertification Nuclei, among which the Seridó Desertification Nucleus (RN-PB). Thus, the present work started from the premise that the desertification process in the Seridó Potiguar (RN) region has possibly caused variability in surface temperature, albedo, and energy and mass fluxes (evapotranspiration / evaporative fraction). To verify the changes resulting from this process, a descriptive / comparative analysis was carried out between degraded area data and preserved Caatinga area (Seridó-ESEC Ecological Station). For this, a hybrid algorithm was used, which is composed of parametrizations of several algorithms such as: Surface Energy Balance Algorithms for Land / SEBAL, Simplified Surface Energy Balance / SSEB, and S-SEBI, and Of images - Landsat 5, of orbits-point: 215/65, acquired free of charge from INPE - National Space Research Institute - under the condition of clear sky, for dates of 1990, 1995, 1998, 1999, 2001, 2003, 2005, 2007. Comparing the results obtained in degraded and vegetated areas, it was observed the existence of differences between the average values of albedo, radiation balance and evaporative fraction. This difference was also significantly demonstrated by means of a statistical test (student's t test), which corroborates the hypothesis that the desertification process derived from the misuse of the soil and the climatic conditions of the region is causing changes in the constituent variables of the Energy balance.