Spatio-temporal topsoil organic carbon mapping of a semi-arid Mediterranean region : the role of land use, soil texture, topographic indices and the influence of remote sensing data to modelling
Articolo
Data di Pubblicazione:
2017
Citazione:
Spatio-temporal topsoil organic carbon mapping of a semi-arid Mediterranean region : the role of land use, soil texture, topographic indices and the influence of remote sensing data to modelling / C. Schillaci, M. Acutis, L. Lombardo, A. Lipani, M. Fantappiè, M. Märker, S. Saia. - In: SCIENCE OF THE TOTAL ENVIRONMENT. - ISSN 0048-9697. - 601-602(2017 Dec), pp. 821-832. [10.1016/j.scitotenv.2017.05.239]
Abstract:
SOC is the most important indicator of soil fertility and monitoring its space-time changes is a prerequisite to establish
strategies to reduce soil loss and preserve its quality. Herewe modelled the topsoil (0–0.3 m) SOC concentration
of the cultivated area of Sicily in 1993 and 2008. Sicily is an extremely variable regionwith a high number
of ecosystems, soils, and microclimates. We studied the role of time and land use in the modelling of SOC, and
assessed the role of remote sensing (RS) covariates in the boosted regression treesmodelling. The models obtained
showed a high pseudo-R2 (0.63–0.69) and low uncertainty (s.d. b 0.76 g C kg−1 with RS, and b1.25 g C kg−1
without RS). These outputs allowed depicting a time variation of SOC at 1 arcsec. SOC estimation strongly
depended on the soil texture, land use, rainfall and topographic indices related to erosion and deposition. RS indices
captured one fifth of the total variance explained, slightly changed the ranking of variance explained by the
non-RS predictors, and reduced the variability of the model replicates. During the study period, SOC decreased in
the areas with relatively high initial SOC, and increased in the areawith high temperature and low rainfall, dominated
by arables. Thiswas likely due to the compulsory application of some Good Agricultural and Environmental
practices. These results confirm that the importance of texture and land use in short-term SOC variation is comparable to climate. The present results call for agronomic and policy intervention at the district level to maintain
fertility and yield potential. In addition, the present results suggest that the application of RS covariates enhanced
the modelling performance.
Tipologia IRIS:
01 - Articolo su periodico
Keywords:
SOC mapping; Space-time SOC variation; Agro-ecosystems; R programming; Digital soil mapping; Legacy dataset
Elenco autori:
C. Schillaci, M. Acutis, L. Lombardo, A. Lipani, M. Fantappiè, M. Märker, S. Saia
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