Dados do Trabalho

Título

ORGANIC CARBON IN PEAT AND ORGANIC SOILS IN CERRADO - FIRST RESULTS FROM PEATLANDS IN STREAM VALLEY WETLANDS

Resumo

Although wetlands in stream valleys - Veredas and riparian swamp forests - harbour peat soils with a high concentration of organic matter, these have been almost entirely overlooked as the ecosystem with the highest carbon density in the Cerrado savanna in Brazil. In this contribution, we present the initial results of the first systematic assessment of peat soil carbon in stream valley wetlands. A total of 640 soil samples from 200 profiles/points were collected in the Chapada dos Veadeiros and Grande Sertão Veredas National Parks, in the Ecological station (ESEC) Serra Geral do Tocantins and in two preserved Veredas near Posse (GO) and Arinos (MG). Carbon content was analysed with the loss-on-ignition method in a muffle furnace. Peat depths of more than 4 meters were found, with an average depth of 96 cm (n = 144). The average bulk density in the peat was 0.19 g/cm³ (SD = ±0.14 g/cm³), the average carbon content was 55% (SD= ±15%) (n=465) and the average carbon stock was 1179 t/ha (SD = ±1012 t/ha) (n=144) ranging between 60 and 4530 t/ha. We show that peatlands as part of Veredas and riparian swamp forests are by far the most carbon-rich ecosystem in the Cerrado due to their high soil organic carbon stocks. That emphasizes their importance for the Cerrado carbon cycle. Due to the current almost complete lack of information, efforts should be focused on mapping stream valley wetlands throughout the Cerrado, especially their peatlands and soil carbon stocks, as well as their degradation status for taking more effective measures in their conservation and protective management.

Palavras-chave

peat; Veredas; organic carbon; Cerrado stream valley wetlands

Instituição financiadora

Heinrich Böll foundation (DE)

Agradecimentos

Marco Borges (ICMBio), José Francisco Gonçalves Junior (UnB)