SOIL RESPIRATION IN AN AGROSILVOPASTORAL SYSTEM IN CENTRAL MEXICO

Abstract

Background. The CO2 emission flow from the soil, known as soil respiration, is an important pathway in the global carbon cycle. Objective. Thus, the objective of the present was to determine the variation of CO2 emissions according to a) different management before, during and after grazing by cattle; b) influence of environmental and soil factors on emissions, as well as c) adjust a model and assess its sensitivity to dimension the applicability in soil respiration behavior. Methodology. The soil respiration was measured every 30 min for 312 hours followed by a closed dynamic chamber of known volume placed on the floor, integrated with an infrared gas analyzer (Model 8100-104). Results. The results indicate that the total emissions in each management were 228, 128 and 241 kg CO2 ha-1 day-1 in an agroforestry system with fruit trees before, during and after grazing, respectively. The ambient temperature influences the respiration of the soil in the three ways. While soil moisture affects only during and after grazing. Implications. Since the results are limited, it is important to evaluate and analyze for long periods of time to understand the behavior of the R in agroforestry systems. Conclusion. In the sensitivity analysis, the increase of 2 ° C and 20% in variables such as precipitation, soil temperature and soil moisture would favor the increase of the CO2 flow from the soil to the atmosphere.