Differences in the superficial storage of organic carbon in soils from different olive orchard cultivation systems and ecosystem service implications (Sierras Subbéticas Natural Park, southern Spain).

According to Pereira et al. (2018) soils provide and regulate many ecosystem services and play an important role in sustaining humanity. The benefits we receive from soils are directly or indirectly linked to clean air and water and food production, among others. The type, quantity or quality of soil ecosystem services depends on the specific environmental characteristics that will determine soil properties and functions. The valuation of soil ecosystem services depends on natural features and management type. Non-sustainable practices induce soil degradation/devaluation and many disservices, while sustainable practices can maintain and improve soil ecosystem services. Overall, soil ecosystem services quality and quantity over the long-term will depend on how sustainably we manage our land. 

In this study, the aim is the assessment of differences between the carbon storage in soils from different olive orchard cultivation systems for a preliminary evaluation of this regulating soil ecosystem service. To do this, we selected four different olive orchard cultivation systems: traditional (no sustainable practices), intensive (no sustainable practices and irrigation), ecological (sustainable practices: no chemical amendments, no tillage, and grass cover), and abandoned (abandoned at least 60-70 years ago and recolonised with shrubs). Soils were sampled following a longitudinal transect from the bottom of the cultivated/abandoned hillslopes to the top: every 10 m disturbed and undisturbed samples were taken in the upper 0-10 cm of soil profile. Once the soil samples were dried in laboratory conditions and sieved to 2 mm, the bulk density and organic carbon content were determined as follows: I) bulk density by the core method (Blake and Hartge, 1986); ii) organic carbon content with the application of the 1.74 factor to the organic matter content obtained by means of calcination. Both parameters let calculate the carbon storage (Ruiz-Sinoga and Romero-Díaz, 2010).   

References: 

Blake, G.R., Hartge, K.H. 1986. Bulk density, In: Klute, A. (Ed.), Methods of Soil Analysis, Part 1, Physical and Mineralogical Methods, 2nd Ed. Agronomy Monograph, 9. American Society of Agronomy and Soil Science, Madison, W, pp. 363–375. 

Pereira, P., Bogunovic, I., Muñoz-Rojas, M., Brevik, E.C. 2018. Soil ecosystem services, sustainability, valuation and management. Current Opinion in Environmental Science & Health, 5:7–13. 

Ruiz-Sinoga, J.D, Romero-Díaz, A. 2010. Soil degradation factors along a Mediterranean pluviometric gradient in Southern Spain. Geomorphology, 118:359–368.