UV radiation and reduced rainfall: Legacy effects on litter and first-year decomposition in two Mediterranean evergreen shrubs
Climatic models for the Mediterranean Basin predict higher ultraviolet (UV) radiation and drier conditions by century’s end, potentially altering litter traits, early-stage decomposition, and nutrient cycling. This study investigates how UV radiation (UV-B and UV-A) and reduced rainfall influence le...
| Autores: | , , , , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2026 |
| País: | España |
| Institución: | Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya) |
| Repositorio: | Recercat. Dipósit de la Recerca de Catalunya |
| OAI Identifier: | oai:recercat.cat:10256/28410 |
| Acceso en línea: | http://hdl.handle.net/10256/28410 https://hdl.handle.net/10256/28410 |
| Access Level: | acceso abierto |
| Palabra clave: | Plantes -- Efecte de la radiació Plants -- Effect of radiation on Radiació ultraviolada Ultraviolet radiation Fullaraca -- Biodegradació Fullaraca -- Efecte de la sequera Plant litter -- Effect of drought on Canvis climàtics Climatic changes |
| Sumario: | Climatic models for the Mediterranean Basin predict higher ultraviolet (UV) radiation and drier conditions by century’s end, potentially altering litter traits, early-stage decomposition, and nutrient cycling. This study investigates how UV radiation (UV-B and UV-A) and reduced rainfall influence leaf litter characteristics and its decomposition in two evergreen sclerophyllous Mediterranean species, Arbutus unedo and Phillyrea angustifolia, growing in a natural shrubland. A field litterbag decomposition experiment was conducted using litter from plants growing in eighteen 9 m2 plots arranged in three blocks. For six years, plots experienced one of three UV radiation conditions: ambient UV, without ambient UV-B, and without ambient UV, combined with two rainfall levels (natural or reduced). Treatments altered the initial leaf litter chemistry. In A. unedo, UV-B exposure decreased the leaf carbon/nitrogen (C/N) ratio (due to higher N) under natural rainfall, while in P. angustifolia, mainly UV-A radiation increased this ratio. Over the studied decomposition period (374 days), leaf litter mass loss in both species was limited, but P. angustifolia litter lost more mass (11 %) than A. unedo litter (3 %), likely due to a lower C/N ratio and a higher microbial activity. UV-A and UV-B radiation affected early litter decomposition in both species by altering recalcitrant compounds and/or microbial biomass, though effects on A. unedo depended on the rainfall amount. Overall, UV radiation appeared to inhibit rather than stimulate decomposition, thus not supporting a predominant role of UV radiation-induced photodegradation. Hence, future climate change may exacerbate present UV and drought effects on litter decomposition, slowing down decomposition rates and enhancing C accumulation in Mediterranean ecosystems |
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