Impacts of land use change in soil carbon and nitrogen in a Mediterranean agricultural area (Southern Spain)

Abstract

Abstract. The agricultural Mediterranean areas are dedicated to arable crops (AC), but in the last decades, a significant number of AC has led to a land use change (LUC) to olive grove (OG) and vineyards (V). A field study was conducted to determine the long-term effects (46 years) of LUC (AC by OG and V) and to determine soil organic carbon (SOC), total nitrogen (TN), C : N ratio and their stratification across the soil entire profile, in Montilla-Moriles denomination of origin (D.O.), in Calcic-Chromic Luvisols (LVcc/cr), an area under semiarid Mediterranean conditions. The experimental design consisted of studying the LUC on one farm between 1965 and 2011. Originally, only AC was farmed in 1965, but OG and V were farmed up to now (2011). This LUC principally affected the horizon thickness, texture, bulk density, pH, organic matter, organic carbon, total nitrogen and C : N ratio. The LUC had a negative impact in the soil, affecting the SOC and TN stocks. The conversion from AC to V and OG involved the loss of the SOC stock (52.7 % and 64.9 % to V and OG respectively) and the loss of the TN stock (42.6% and 38.1 % to V and OG respectively). With respect to the stratification ratios (SRs), the effects were opposite; 46 years after LUC increased the SRs (in V and OG) of SOC, TN and C : N ratio.

Multi-scale variability of soil carbon and nitrogen in the middle reaches of the Heihe River basin, northwestern China

“…It has been shown that N mineralization decreases when clay content increases in soil (Côté et al, 2000;Corral-Fernández et al, 2013;Parras-Alcántara et al, 2013). In the 0-80 cm soil profiles, the average silt and sand contents were 56.0% and 41.1%, respectively.…”

Soil organic carbon along an altitudinal gradient in the Despeñaperros Natural Park, southern Spain

“…Gallardo et al (2000) showed that the low OM content could be explained by the semiarid Mediterranean conditions. In addition, Parras-Alcántara et al (2013a) found there is less OM and fewer mineral aggregates in sandy soils, thus favoring high levels of OM transformation. Because of this, Hontoria et al (2004) suggested that physical variables determine soil development in the driest areas of Spain to a greater degree than management or climatic variables.…”

Effects of permanent grass versus tillage on aggregation and organic matter dynamics in a poorly developed vineyard soil

“…Munoz-18 Rojas et al 2012;De Moraes Sá et al 2013;Gelaw et al 2013;Parras-Alcántara et al 2013, 201419 Srinivasarao et al 2014;Yu and Jia 2014;Behera et al 2015;Peng 2015). Agriculture can strongly 20 limit SOM accumulation, influencing soil aggregate formation and turnover (Jastrow 1996;Cerdà, 21 2000;Jacobs et al 2010;Gosling et al 2013).…”