Prediction of the alterations in carbon cycling induced by the intensification and diversification of pasture management systems in Brazil

Abstract

The degradation of pasture areas in Brazil makes it difficult to provide ecosystem services, among which, is the mitigation of global climatic change through the accumulation of stable C in the form of soil organic matter (SOM). Therefore, monitoring tools that permit the spatial and temporal predictions about SOM in pasture areas could help in making decisions about sustainable pasture management. The present proposal for an internship abroad is part of a PhD project entitled "Alterations in the cycling and accumulation of carbon induced by the intensification and diversification of pasture management systems". The project has as its principal objectives: a) The quantification of the accumulation of C and N in the soil under different pasture management systems in Brazil (e.g., degraded pasture, rotational, crop-livestock integration and agroforestry systems) according to the original SOM levels; b) Compare the observed in situ results with the simulated results; c) Develop prospective scenarios for the different intensive and diversified pasture management systems, as well as associated changes in C and N soil stocks, in order to generate results to support/subsidize public policies (e.g. ABC Plan/Program). To do this, simulations with the DayCent model will be carried out during the internship period at the Department of Soil and Crop Sciences and the Natural Resource Ecology Laboratory (Colorado State University) in order to predict the effects on SOM due to the adoption of more intensive and diversified pasture management systems in Brazil. The results obtained should allow the improvement of prediction models for increasing soil C stocks in pasture areas and contribute to the implementation of public polices with the objective of recovering degraded areas and securing environmental sustainability of the Brazilian agricultural sector. (AU)