EGU25-12570, updated on 15 Mar 2025
https://doi.org/10.5194/egusphere-egu25-12570
EGU General Assembly 2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
What is more impactful on water fluxes and soil erosion: changes in land cover or climate variability? 
Dimaghi Schwamback1,2, Abderraman R. Amorim Brandão1, Linus Zhang2,3, Ronny Berndtsson2,3, Edson Wendland1, and Magnus Persson2,3
Dimaghi Schwamback et al.
  • 1Department of Hydraulics and Sanitation, São Carlos School of Engineering at University of São Paulo, São Carlos, Brazil (dimaghis@gmail.com)
  • 2Division of Water Resources Engineering, Lund University, Lund, Sweden
  • 3United Nations University Hub on Water in a Changing Environment (WICE) at Lund University, Lund, Sweden

Agricultural-driven land-use changes have extensively reshaped landscapes, leading to increased soil erosion and water demand. Achieving long-term agricultural sustainability requires a balanced interaction among water resources, land cover, and climate. However, how this interconnected system will respond to climate change remains uncertain. This study aims to assess (i) the current impacts of land cover changes on water balance variables and soil erosion and (ii) the projected impacts of future climate conditions.  Field observations were conducted on 100 m² experimental plots in Brazil, maintained over the past decade. We evaluated the long-term trade-offs between common agricultural land covers—sugarcane, pasture, and soybean—and their effects on runoff and soil loss rates. Results were compared to those for native forest (wooded Cerrado) and bare soil. A significant difference between agricultural land and native forest were found. For instance, areas converted to pasture experienced nearly 20 times higher runoff, while sugarcane cultivation resulted in soil loss rates five times greater than native forest. To analyze future impacts, we applied the Universal Soil Loss Equation (USLE) and Hydrus model, integrating them with CMIP6 climate projections under SSP2-4.5 and SSP5-8.5 scenarios for the intermediate (2040–2070) and distant future (2071–2100). The results indicated that climate change will variably affect water flux components in a hierarchical sequence: soil-water storage, bottom flux, infiltration, surface flux, evaporation, and root uptake. For example, we estimated an increase of 23% in root water uptake and reduction of 8% in soil-water storage in sugarcane. This pattern was consistent across all types of land cover, differing primarily in magnitude. Regarding soil erosion, our projections indicated increases of 4.9% under SSP2-4.5 and 7.6% under SSP5-8.5 scenarios for all land covers. The observed soil loss rates highlight the critical need for sustainable land management to mitigate soil degradation. Notably, ongoing land cover changes pose a greater risk to water fluxes than projected climate changes. However, shifts in rainfall patterns due to climate change are likely to increase rainfall erosivity, amplifying soil erosion potential. Consequently, land conversion presents substantial risks to soil stability at both local and continental scales. These findings underscore the urgency of adopting targeted soil and water conservation strategies in the Cerrado biome. By mitigating soil erosion and promoting sustainable land-use practices, these strategies can help balance agricultural productivity with ecological preservation under current and future climate scenarios.

How to cite: Schwamback, D., R. Amorim Brandão, A., Zhang, L., Berndtsson, R., Wendland, E., and Persson, M.: What is more impactful on water fluxes and soil erosion: changes in land cover or climate variability? , EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-12570, https://doi.org/10.5194/egusphere-egu25-12570, 2025.