217-3 Soil Respiration From Degraded and Managed Pasture in Southeast of São Paulo State, Brazil.

Poster Number 1209

See more from this Division: ASA Section: Environmental Quality
See more from this Session: Carbon Emissions From Agriculture

Tuesday, November 5, 2013
Tampa Convention Center, East Exhibit Hall

Eduardo Barretto de Figueiredo Sr.1, Ricardo De Oliveira Bordonal2, Alan Rodrigo Panosso3, Telma Terezinha Berchielli4 and Newton La Scala Júnior1, (1)Exact Science, São Paulo State University (FCAV/UNESP), Jaboticabal, Brazil
(2)Exact Science, Universidade Estadual Paulista - UNESP, Orlândia, (Non U.S.), BRAZIL
(3)São Paulo State University (FCAV/UNESP), Ilha Solteira/SP, Brazil
(4)Department of Animal Science, Universidade Estadual Paulista “Júlio de Mesquita Filho” – Unesp, Jaboticabal - SP, Brazil
Abstract:
Soil respiration is a process by which the carbon dioxide is released inside soil either by microorganisms or plant roots and delivered to atmosphere (Rochette et al., 1991). However, soil respiration is characterized by a high spatial and temporal variability (Currie 1974), and relation with management practices. This research aimed to study the differences and similarities of soil respiration (FCO2) from degraded and managed pasture in southeast of São Paulo State, Brazil. FCO2 was measured simultaneously in both areas in 08 days, during the mornings, with two portable LI-COR systems (LI-8100, Lincoln, NE, USA). In each of those areas a grid having 100 m × 100 m with 102 measurement points was installed, with points distributed at distances from 5–20 m apart. Degraded pasture (DP) is characterized as an area which receives no appropriate management practice in the last 5 years. Managed pasture (MP) is described here as the area that has been managed under crop rotation after sugarcane, with maize and later with Brachiaria brizantha for the last 3 years, in addition with paddock grazing rotation (6 head ha-1). Our results show average emissions of 8.73 (± 0.86) and 5.96 (± 0.69) µ mol m-2 s-1 for DP and MP, respectively. Higher FCO2 in DP, where plants height and ground cover were lower compared to MP, could point to higher soil C losses in degraded conditions.

See more from this Division: ASA Section: Environmental Quality
See more from this Session: Carbon Emissions From Agriculture