Capacitat de segrest de carboni dels sòls del Campus de Montilivi/ UdG

Abstract

The soil is a natural resource not renewable in the short term that is involved in processes affecting environmental quality, such as the ability to sequester atmospheric CO2.This relevance is not always taken into account. Within this context, soil carbon sequestration may be related to factors of formation, such parent material, climate, living organisms, geomorphology and chronological time, as main determinants of the processes of edaphogenesis. In the surroundings of the Montilivi campus of the Universitat de Girona (study area), climate, biotic entities, geomorphology and time are considered similar, whilst two different geological units in the geological map 1:50.000 of the Institut Cartogràfic i geològic de Catalunya (NPlac i Qac) were identified. This paper aims to characterize four soil profiles located in the study area (profiles 1, 2 and 3 formed on the NPlac unit and 4 on Qac), assess the soil carbon sequestration capacity and determine which parameters may have more influence on it. Different physicochemical parameters have been determined (gravel, bulk density, particle size separates, textural class, pH, electrical conductivity, carbonates, total organic carbon, oxidizing carbon and total nitrogen) of the different horizons of the four profiles. In addition, different biochemical parameters related to the carbon cycle have been determined in the surface horizons of these profiles (potential soil respiration, daily respiratory activity, mineralization coefficient, total glomalin and easily extractable glomalin). The results obtained, from the four soil profiles, classified as Typic Haploxerept (Profiles 1 and 3), Typic Calcixerept (Profile 2) and Inceptic Haploxeralf (Profile 4), showed differences in physicochemical (pH, electrical conductivity, bulk density, organic carbon, nitrogen, carbonates and texture) and biochemical properties (total glomalin and easily extractable glomalin). Soil profiles 2 and 4 were mostly differentiated due to the presence of carbonates and higher abundance of organic decaying debris, respectively. The geological setting (NPlac) on which lays profile 2 presents a discontinuity formed by a calcareous crust