Variabilidade pluviométrica e do balanço hídrico no sistema agropecuário do núcleo de desertificação do médio Jaguaribe-CE

Abstract

High evapotranspiration and irregular spatiotemporal rainfall have serious impacts on agricultural development in the semi-arid region of Ceará, leading to increased production costs, crop failures, and reduced food security. Dry spells, which are consecutive days with no precipitation during the rainy season, exacerbate this environmental fragility, leading to increased crop losses. The Climatological Water Balance provides important data and information on environmental potential and limitations, aiding regional agricultural and hydroclimatic planning. This research aims to assess the impact of semiarid conditions, based on hydroclimatic and socioeconomic aspects, on the agricultural system in the area susceptible to desertification in the Middle Jaguaribe. This research used statistical methods— Pearson's correlation method (r), coefficient of determination (R2), and linear regression models (univariate and multivariate)—to correlate and discuss the estimated variables. In addition to using the Thornthwaite and Mather hydroclimatological balance and calculating the degrees of drought and crop losses. Given the above, it is possible to conclude that dry spells were the climatic variable that demonstrated the greatest impact on the productivity of temporary crops (corn and beans), indicating that prolonged periods of drought during the rainy season are the main climatic agents responsible for the loss of agricultural productivity. This fact was confirmed in the univariate and multivariate linear regression models. Stronger correlations were observed between the climatic variables and agricultural production (beans and corn), while livestock production (cattle, goats, sheep, swine, milk, honey) and forestry production (charcoal and firewood) showed weaker or insignificant correlations with the analyzed climatic factors. Water deficits were highest during the period from September to December. This is due to the absence or drastic reduction of rainfall during these months. Therefore, with the greatest rainfall scarcity during this period, the deficit intensifies