Solar UV-A radiation and blue light enhance tree leaf litter decomposition in a temperate forest.

Autor: Pieristè M; Organismal and Evolutionary Biology (OEB), Viikki Plant Science Centre (ViPS), University of Helsinki, P.O. Box 65, Viikinkaari1, 00014, Helsinki, Finland. marta.pieriste@helsinki.fi.; Normandie Université, UNIROUEN, IRSTEA, ECODIV, FR Scale CNRS 3730, Rouen, France. marta.pieriste@helsinki.fi., Chauvat M; Normandie Université, UNIROUEN, IRSTEA, ECODIV, FR Scale CNRS 3730, Rouen, France., Kotilainen TK; Organismal and Evolutionary Biology (OEB), Viikki Plant Science Centre (ViPS), University of Helsinki, P.O. Box 65, Viikinkaari1, 00014, Helsinki, Finland.; Natural Resources Institute Finland, Itäinen Pitkäkatu 4a, 20520, Turku, FI, Finland., Jones AG; Earthwatch Institute, Mayfield House, 256 Banbury Road, Oxford, OX2 7DE, UK.; Forest Systems, Scion. 49 Sala Street, Private Bag 3020, Rotorua, 3046, New Zealand., Aubert M; Normandie Université, UNIROUEN, IRSTEA, ECODIV, FR Scale CNRS 3730, Rouen, France., Robson TM; Organismal and Evolutionary Biology (OEB), Viikki Plant Science Centre (ViPS), University of Helsinki, P.O. Box 65, Viikinkaari1, 00014, Helsinki, Finland., Forey E; Normandie Université, UNIROUEN, IRSTEA, ECODIV, FR Scale CNRS 3730, Rouen, France.
Jazyk: angličtina
Zdroj: Oecologia [Oecologia] 2019 Sep; Vol. 191 (1), pp. 191-203. Date of Electronic Publication: 2019 Jul 30.
DOI: 10.1007/s00442-019-04478-x
Abstrakt: Sunlight can accelerate the decomposition process through an ensemble of direct and indirect processes known as photodegradation. Although photodegradation is widely studied in arid environments, there have been few studies in temperate regions. This experiment investigated how exposure to solar radiation, and specifically UV-B, UV-A, and blue light, affects leaf litter decomposition under a temperate forest canopy in France. For this purpose, we employed custom-made litterbags built using filters that attenuated different regions of the solar spectrum. Litter mass loss and carbon to nitrogen (C:N) ratio of three species: European ash (Fraxinus excelsior), European beech (Fagus sylvatica) and pedunculate oak (Quercus robur), differing in their leaf traits and decomposition rate, were analysed over a period of 7-10 months. Over the entire period, the effect of treatments attenuating blue light and solar UV radiation on leaf litter decomposition was similar to that of our dark treatment, where litter lost 20-30% less mass and had a lower C:N ratio than under the full-spectrum treatment. Moreover, decomposition was affected more by the filter treatment than mesh size, which controlled access by mesofauna. The effect of filter treatment differed among the three species and appeared to depend on litter quality (and especially C:N), producing the greatest effect in recalcitrant litter (F. sylvatica). Even under the reduced irradiance found in the understorey of a temperate forest, UV radiation and blue light remain important in accelerating surface litter decomposition.
Databáze: MEDLINE