Socio-Environmental Vulnerability to Drought Conditions and Land Degradation: An Assessment in Two Northeastern Brazilian River Basins

Abstract

Over the past few decades, a significant amount of agricultural land has been lost due to soil degradation/desertification. In addition, the increasing frequency of extreme events, such as intense droughts and forest fires, has negatively impacted various ecosystem services. Two of the main Brazilian biomes—the Cerrado and the Caatinga—have been affected by increased rainfall variability, leading to desertification, increased fire frequency, and, consequently, rising concerns regarding the water and food security of the local population. In this study, we develop a methodology to assess these impacts using a Socio-Environmental Vulnerability Index (SEVI) that combines physical, environmental, and socio-economic indicators related to exposure, sensitivity, and adaptation, as well as including socio-environmental feedback. The developed SEVI is then applied to the São Francisco and Parnaíba river basins. The proposed index is based on the MEDALUS methodology and is adapted to include multiple biological, physical, and socio-economic indicators, allowing for the discrimination of areas characterized by different levels of vulnerability. We also analyze the effectiveness of governmental policies, such as the creation of conservation areas and the rural registration of properties, in reducing vulnerability. The SEVI analysis highlights that adaptive capacity is the main constraint for reducing socio-environmental vulnerability in the Parnaíba basin, while exposure and sensitivity are the greater challenges in the São Francisco basin. The results of this study are crucial for the prioritization of recovery actions in degraded areas.

Greening and Water Use Efficiency during a period of high frequency of droughts in the Brazilian semi-arid

“…We understand that the WUE has certainly helped mitigate the impact of droughts. However, the current trend is that this resilience may gradually weaken over time, leading to increased soil degradation and accelerated desertification in the already observed Brazilian semiarid region (Tomasella et al, 2018;Vieira et al, 2023). Also, the sites that had a positive trend in the increase of LAI, such as Parque Sete Cidades and Triunfo have more favorable climatic conditions: warm and humid (Köppen classification: Aw) and wet mesothermal, microclimate restricted to mountains (Köppen classification: Csa), respectively.…”

“…The Brazilian Semi-arid has undergone desertification due to the increase of prolonged droughts and uncontrolled burning that favors soil erosion and increases river sediment loads and sedimentation (Swanson, 1981;Pompeu, 2022). As a result, the chemical, physical, and biological characteristics of the soil are altered, further favoring soil erosion, compaction, and loss (Redin et al, 2011), and accelerating soil degradation and the desertification process (Tomasella et al, 2018;Vieira et al, 2023). Based on information from AdaptaBrasil, a platform focused on managing climate change risks and adaptations in Brazil (AdpataBrasil, 2023), the semi-arid region faces significant threats from droughts both currently and in the future decades of 2030s and 2050s.…”

Geospatial Insights into Aridity Conditions: MODIS Products and GIS Modeling in Northeast Brazil

“…At a global level, the intensification of extreme climate change events mainly affects rainfall rates, driving severe droughts. In addition, the impacts caused by human activities also accelerate and lead to significant changes [3][4][5][6], with emphasis for semiarid areas of Brazil, such as the Northeast Region (NEB) and Brazilian Semiarid Region, where studies on the detection of vulnerabilities related to environmental degradation processes and soil desertification, based on radiation and energy balance components, help to understand the dynamics of these factors over time [7][8][9][10][11][12][13][14][15][16].…”

“…Nevertheless, a substantial portion of the NEB area depends on and lacks the necessary conditions for meaningful and participatory action planning, as well as effective water and soil management. This shortfall significantly hinders its developmental potential, ultimately affecting the quality of life of the local population [16,34]. NEB has predominantly the Caatinga biome, located in the BSR, considered the most populous semiarid region in the world.…”

Environmental quality assessment of soil as a component of green spaces in parks of the megalopolis

“…(Macías et al, 2020). This process results in desertification -land degradation with the loss of vegetation cover and biological diversity as a whole, affecting all regions around the world (Briassoulis, 2019;Vieira et al, 2023).…”