Article
Changes in Soil Quality and Hydrological Connectivity Caused by the Abandonment of Terraces in a Mediterranean Burned Catchment Aleix Calsamiglia 1,2, *, Manuel Esteban Lucas-Borja 3 Julián García-Comendador 1,2 ID and Joan Estrany 1,2 1 2 3
*
ID
, Josep Fortesa 1,2 ,
ID
Department of Geography, University of the Balearic Islands, E-07122 Palma, Mallorca, Balearic Islands, Spain;
[email protected] (J.F.);
[email protected] (J.G.-C.);
[email protected] (J.E.) Institute of Agro-Environmental and Water Economy Research—INAGEA, University of the Balearic Islands, E-07122 Palma, Mallorca, Balearic Islands, Spain Departamento de Ciencia y Tecnología Agroforestal y Genética, Universidad de Castilla la Mancha, Campus Universitario s/n, E-02071 Albacete, Spain;
[email protected] Correspondence:
[email protected]; Tel.: +34-971-17-2361
Received: 22 June 2017; Accepted: 7 September 2017; Published: 8 September 2017
Abstract: Wildfires and agricultural activities are relevant factors affecting soil quality, hydrological cycle and sedimentary dynamics. Land abandonment leads to afforestation, which increases fire risk and land degradation. However, no studies have yet evaluated the effect of combining the two factors, which occur frequently in Mediterranean ecosystems. This study assessed the changes in soil quality caused by the abandonment of terraces in two microcatchments ( 0.73, p = 0.001) were observed between unburned plots without terraces (G1) and the other plots under different representative conditions (G2, G3, G4). Plots belonging to G1, considered as reference plots, were characterized by high organic matter and MBC contents, balanced C/N ratios, greater soil respiration and a higher enzymatic activity than burned and/or terraced plots. The higher soil quality in these plots could be attributed to the presence of greater vegetation cover (60%) than in burned plots. However, unburned terraced plots (UT), with even greater vegetation cover (70%), also showed lower MBC/TOC, lower respiration, and enzymatic activity values closer to burned plots, indicating an important role of different factors such as species composition and agricultural activities during the past. While reference plots were covered by natural forest mainly consisting of Quercus ilex (60%), vegetation on unburned terraced plots was mostly young Pinus halepensis (
