Identification of levels of anthropization and its implications in the process of desertification in the Caatinga biome (Jeremoabo, Bahia-Brazil)

Abstract

Desertification is one of the most serious current environmental problems and corresponds to the impoverishment and decrease of moisture in sandy soils located in regions with a sub-humid, arid and semiarid climate, with its main causes related to climatic variations and the resulting negative impacts of human activities. Studies show that the soils located in the Brazilian semiarid and especially in the Caatinga biome have been suffering an intense process of desertification due to the replacement of natural vegetation as a result of economic activities. Most municipalities that have an economy based on agropastoral activities are at the centre of desertification in several centres in Brazil. Based on this context and considering that the original vegetation cover is a preponderant factor for soil conservation, and subsequently for the maintenance of the ecological stability of the Caatinga biome, this work aimed to map the vegetation cover of the Vaza-Barris watershed corresponding to the municipality of Jeremoabo (Bahia-Brazil), with the purpose of identifying and quantifying, in terms of surface, the main types of interaction between human activities and the remnants of the vegetation cover, listing the potential impacts that have a direct consequence on the desertification processes. The delimitation of the vegetation cover was the result processing Sentinel 2A satellite images and the use of the Soil Adjusted Vegetation Index - SAVI. Five thematic classes representative of the study area were identified, classified according to the increasing level of anthropization that allowed us to conclude that desertification causes damage to agriculture, making the areas unproductive, as well as excessive agriculture with inappropriate practices causes the loss of fertility of the soils, aggravating the desertification process. With this, the environmental and social quality is threatened, considering that the main source of income in the municipality of Jeremoabo comes from agricultural activities and these are dependent on climatic conditions, soil conservation and water resources.

Assessment of Land Degradation and Droughts in an Arid Area Using Drought Indices, Modified Soil-Adjusted Vegetation Index and Landsat Remote Sensing Data

“…Because of the increased intensity and frequency of severe events such as droughts, heatwaves, sandstorms, forest fires, and floods, scientists are now focusing on the effects of climate change (e.g., Corwin, 2021;Malhi et al, 2021;Niñerola et al, 2020;Camarasa-Belmonte, 2021;Rodrigo-Comino et al, 2022;Eekhout et al, 2021). Droughts are one of the most complicated extreme climatic situations, affecting more people than any other hazard or natural disaster (Wilhite, 2000;Oliveira-Santos et al, 2022;Mendoza-Uribe, 2022). The impacts of droughts have generally been referred to as direct impacts, such as reducing vegetation cover and decreasing soil and vegetation water content (Van Leeuwen et al, 2019;Valdes-Abellan et al, 2020;Palacios-Cabrera et al, 2022;Silva et al, 2022).…”