Sociedade & Natureza
On-line version ISSN 1982-4513
ROSENDO, Jussara dos Santos and ROSA, Roberto. Comparison of the estimated C stock in pastures and native Cerrado vegetation. Soc. nat. [online]. 2012, vol.24, n.2, pp. 359-376. ISSN 1982-4513. http://dx.doi.org/10.1590/S1982-45132012000200014.
The climate changes are considered a threat to the environment and for the sustainable development in the world. They are caused by the increase in the greenhouse effect above the desirable level, mainly due to CO2, CH4 and N2O in the atmosphere, even though CO2 is the most abundant. The soils are recognized as important greenhouse gases sinks, especially for CO2. The main objective of this paper was to compare the carbon stock stored in soils under pasture and soils under native cerrado vegetation, in Araguari River basin in Minas Gerais state. The research methodology involved the following steps: selection of the areas occupied by pastures and cerrado; collecting soil samples for carbon to define the carbon stock and laboratory analysis. With the support of TM/Landsat5 sensor, soil samples were collected in the field under improved pastures of brachiaria, degraded pastures of brachiaria and cerrado, at 0 to 20 cm and 20 to 40 cm depths. The results reached showed that the improved pasture to the layer from 0 to 20 cm showed a carbon stock of 43,92 Mg C ha-1, while cerrado showed 38,05 Mg C ha-1 and the degraded pasture 34,63 Mg C ha-1, while the depth from 20 to 40 cm, the improved pasture reached 33,5 Mg C ha-1, the cerrado 26,80 Mg C ha-1 and the degraded pasture 27,51 Mg C ha-1, what allow us to conclude that pastures well established and managed can contribute to the increasing of the rate of carbon sequestration in the soil. However, the lack of soil remediation, fertilizer maintenance, erosion control and proper management, with overcrowding (overgrazing) has led the pastures to a stage of degradation, which compromises the ability of those to sequester carbon.
Keywords : C stock in the soils; pastures; Cerrado.