Mediterranean vineyards face a growing threat from heavy rains and soil degradation that strip away fertile topsoil. New research led by scientists at the University of Aveiro, Portugal, shows that adding biochar, a carbon-rich material made from plant waste, can dramatically reduce erosion and improve the soil's ability to store water.
The study, published in Biochar, is among the first to test biochar's impact on the "soil sponge function" under natural rainfall in sloping Mediterranean vineyards. Over 18 months, researchers used outdoor lysimeters filled with vineyard soil and amended half with 4 percent biochar produced from pine wood chips.
Results showed striking benefits. Biochar-treated soils reduced surface runoff by an average of 45 percent and cut overall soil erosion by two-thirds compared with untreated soil. The erosion rate dropped from 11.1 to 3.7 tons per hectare per year. Biochar also improved soil structure, lowering bulk density by 7 percent and increasing infiltration by 28 percent. During dry periods, biochar-amended soils stored up to three times more water than control soils.
"Biochar acted like a sponge in the soil, soaking up rainfall and releasing it slowly," said lead author Behrouz Gholamahmadi of the University of Aveiro's Centre for Environmental and Marine Studies (CESAM). "This helped prevent intense runoff that carries away topsoil and nutrients."
The team found that biochar's porous structure and coarse particles enhanced the soil's capacity to absorb and retain water, even under intense Mediterranean rainstorms. The effects were especially strong during dry months when soil moisture was lowest.
Co-author Frank Verheijen noted that vineyard soils are often exposed and located on slopes, making them highly vulnerable to erosion. "Our findings show that biochar can be a sustainable management tool to increase vineyard resilience to extreme weather and support long-term soil health," he said.
The researchers recommend monitoring biochar's effects through full hydrological cycles to capture seasonal changes and variations caused by atmospheric river events. They also see potential to combine biochar with other soil conservation practices such as cover crops or mulching.
The study highlights biochar's promise as a climate-smart strategy for Mediterranean agriculture, capable of conserving soil, improving water use efficiency, and helping combat land degradation across Europe's most erosion-prone vineyards.
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Journal Reference: Gholamahmadi, B., Ferreira, C.S.S., Gonzalez-Pelayo, O. et al. Soil conservation benefits of biochar in Mediterranean vineyards: enhancing the soil sponge function and mitigating water erosion. Biochar 7, 106 (2025). https://doi.org/10.1007/s42773-025-00483-x
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About Biochar
Biochar is the first journal dedicated exclusively to biochar research, spanning agronomy, environmental science, and materials science. It publishes original studies on biochar production, processing, and applications—such as bioenergy, environmental remediation, soil enhancement, climate mitigation, water treatment, and sustainability analysis. The journal serves as an innovative and professional platform for global researchers to share advances in this rapidly expanding field.
