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RESEARCH ARTICLE

Soil organic carbon fractions under conventional and no-till management in a long-term study in southern Spain

R. Carbonell-Bojollo A F , E. J. González-Sánchez B C , M. Repullo Ruibérriz de Torres A , R. Ordóñez-Fernández A , J. Domínguez-Gimenez D and G. Basch E
+ Author Affiliations
- Author Affiliations

A Area of Ecological Production and Natural Resources, IFAPA Centro Alameda del Obispo, Apdo 3092, 14080 Córdoba, Spain.

B Spanish Association for Conservation Agriculture/Living Soils (AEAC.SV), Building 3, Olivicultura, IFAPA Centro Alameda del Obispo, Av. Menéndez Pidal, 14004 Córdoba, Spain.

C Rural Engineering Department, Edificio Leonardo Da Vinci. Campus de Rabanales, University of Córdoba, Ctra. Nacional IV km 396, 14014 Córdoba, Spain.

D Area of Crop Production, IFAPA Centro Alameda del Obispo, Apdo 3092, 14080 Córdoba, Spain.

E Institute of Mediterranean Agricultural and Environmental Sciences. Universidad de Evora, Apdo 92, vP-7002-554 Evora, Portugal.

F Corresponding author. Email: rosam.carbonell@juntadeandalucia.es

Soil Research 53(2) 113-124 https://doi.org/10.1071/SR13369
Submitted: 20 December 2013  Accepted: 31 October 2014   Published: 25 February 2015

Abstract

In dryland farming systems under a Mediterranean climate, soil quality and productivity can be enhanced by increasing the content of soil organic carbon (SOC) through alternative soil management systems. Some fractions of C are directly involved in increasing total SOC and therefore in enhancing any benefits in terms of soil properties. This study compares the viability of no-till farming (NT) with conventional (traditional) tillage (TT) for improving SOC levels. The influence of management practices was investigated for different fractions of C (particulate OC, active OC, humic acids, fulvic acids) and CO2 emissions in clayey soils in the south of Spain. The experiment was conducted over three farming seasons (2006–07, 2007–08 and 2008–09) covering a crop rotation of peas (Pisum sativum L.), wheat (Triticum aestivum L.) and sunflowers (Helianthus annuus L.). The NT system improved the levels of the different fractions of C in the surface soil and reduced the amount of CO2 released into the atmosphere compared with the TT system. Generally, the relationship between CO2 and SOC content was greater in soils under NT for the farming seasons sampled.

Additional keywords: conventional tillage, CO2 emissions, no tillage, particulate organic carbon, soil organic carbon.


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