DRY PERIODS, DROUGHTS AND THE SANDIZATION PROCESSES IN MIRACATU CREEK WATERSHED, SOUTHWEST OF RIO GRANDE DO SUL STATE, BRAZIL

• Autor(a) principal: Binda, Andrey Luis
• Data de Publicação: 2020
• Outros Autores: Verdum, Roberto
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: GeoTextos (Online)
• Texto Completo: https://periodicos.ufba.br/index.php/geotextos/article/view/38159
• topic: Rain; Dry periods; Droughts; Sandy areas; Soil erosion; Precipitação; Estiagem; Seca; Areais; Erosão dos solos

The sandization processes in the southwest of Rio Grande do Sul State are highly dynamic, sometimes through water action, sometimes due to winds action that remobilize sandy deposits in dry periods with no rain. Thus, both the excess and the absence of rain are fundamental for understanding this process. Based on this assumption, the present work aims to analyze the occurrence of droughts and dry periods considering a rainfall data series (1970-2015) collected in the Miracatu Creek Watershed, site where there is the largest extension of areas in the sandization process. Considering the methodology used to determine drought episodes (periods with more than 15 consecutives dry days), it was found that there were records in practically every year studied (except one). Monthly, the pyramidal distribution of episodes puts the May July quarter as the most favorable, although they can occur at any time of the year. However, the greater frequency of droughts in the 1970s reflects a long dry period, whose determination was possible based on the Standardized Precipitation Index.