title: Characterization of water dissolved organic matter under woody vegetation patches in semi-arid Mediterranean soils.
abstract: Woody patches in semiarid environments favor the establishment of other plants. Facilitation may be favored by an increase in soil fertility. Dissolved organic matter (DOM), is the most active fraction of soil organic matter and may contain compounds affecting plant establishment, as allelochemicals, hormone-like substances and metal carriers. However, information on DOM contents and composition in these environments is scarce. In this paper, we study the impact of woody patches on DOM in Stipa tenacissima L. steppes and discuss its implications for community dynamics. DOM under patch- and inter-patch areas, was analyzed for elemental composition, UV-Vis indices and organic acid content. Element concentration and composition in DOM, and organic acid concentration were similar in patch- and inter-patch areas. Yet, soils under patches were richer in DOC, aromatic species and organic acids (particularly fumaric acid) than soils in inter-patch areas. Dominant species affected organic matter concentration and quality in complex ways. Thus, patches dominated by Ephedra fragilis showed higher concentrations of TOC and aromatics than those dominated by other species. Rhamnus lycioides patches showed the highest accumulation of fumaric acid, which may contribute to its successful recruitment rate and expansion in the area. Our results show substantial differences in the amount and composition of DOM and specific compounds affecting soil functionality and plant dynamics. Further studies on the effects of such changes on seedling performance are needed to increase our understanding of plant-plant interactions in semiarid environments.
authors.affiliation: Dep. Agrochemistry and Biochemistry, Faculty of Sciences, University of Alicante, Ap. 99, 03080 Alicante, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Cerdán
authors.affiliation: Dep. Agrochemistry and Biochemistry, Faculty of Sciences, University of Alicante, Ap. 99, 03080 Alicante, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Sánchez-Sánchez
authors.affiliation: Institute for Environmental Research, Ramon Margalef, University of Alicante, Ap. 99, 03080 Alicante, Spain. Electronic address: juana.jorda@ua.es.
authors.forename: J D
authors.initials: JD
authors.lastname: Jordá
authors.affiliation: Department of Ecology, Faculty of Sciences, University of Alicante, Ap. 99, 03080 Alicante, Spain.
authors.forename: B
authors.initials: B
authors.lastname: Amat
authors.affiliation: Institute for Environmental Research, Ramon Margalef, University of Alicante, Ap. 99, 03080 Alicante, Spain; Department of Ecology, Faculty of Sciences, University of Alicante, Ap. 99, 03080 Alicante, Spain.
authors.forename: J
authors.initials: J
authors.lastname: Cortina
authors.affiliation: Dep. Agrochemistry and Biochemistry, Faculty of Sciences, University of Alicante, Ap. 99, 03080 Alicante, Spain.
authors.forename: N
authors.initials: N
authors.lastname: Ruiz-Vicedo
authors.affiliation: Dep. Agrochemistry and Biochemistry, Faculty of Sciences, University of Alicante, Ap. 99, 03080 Alicante, Spain.
authors.forename: M
authors.initials: M
authors.lastname: El-Khattabi
keywords: Aridity; DOC; Fumaric; Phenols; TOC