Articles | Volume 12, issue 2
https://doi.org/10.5194/soil-12-915-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/soil-12-915-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Original research article
| 
23 Sep 2026
Original research article |
| 23 Sep 2026
| 23 Sep 2026
Soil moisture as the dominant driver of CO2 efflux in Mediterranean urban green spaces: evidence for a Gaussian temperature response and mechanistic modelling of moisture and temperature interactions
Teresa Alía
Facultad de Farmacia, Unidad Docente de Edafología, Universidad Complutense de Madrid, Plaza Ramón y Cajal s/n, 28040, Madrid, Spain
Facultad de Farmacia, Unidad Docente de Edafología, Universidad Complutense de Madrid, Plaza Ramón y Cajal s/n, 28040, Madrid, Spain
Abel Sánchez-Jiménez
Departamento de Biodiversidad, Ecología y Evolución, Facultad de Ciencias Biológicas, Universidad Complutense de Madrid, C/ José Antonio Novais, 12, 28040, Madrid, Spain
Rubén Abad-Calderón
Facultad de Farmacia, Unidad Docente de Edafología, Universidad Complutense de Madrid, Plaza Ramón y Cajal s/n, 28040, Madrid, Spain
Miguel Ángel Casermeiro
Facultad de Farmacia, Unidad Docente de Edafología, Universidad Complutense de Madrid, Plaza Ramón y Cajal s/n, 28040, Madrid, Spain
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Short summary
Urban parks store and release carbon, but what controls this process in Mediterranean cities remains poorly understood. We monitored carbon dioxide emissions from soils in three Madrid parks over one year and found that soil moisture, not temperature, is the main driver. Surprisingly, emissions declined at high temperatures, not because heat suppresses soil life, but because hot summers dry out the soil. Keeping urban soils moist is key to managing their carbon balance under climate change.
Urban parks store and release carbon, but what controls this process in Mediterranean cities...
