Temperature effect on CARBON biomass in soils FROM TROPICAL AND TEMPERATE REGIONS

Four soils from various origins, (tropical and temperate regions) were amended with 14C labelled glucose (1mg C.g-1 soil) and incubated at 15ºC and 35ºC to determine the temperature effect on the carbon turnover and on the microbial biomass. The temperature effect on the biomass increased with the glucose addition. The biomass mineralization rates were higher at 35ºC than at 15ºC and higher for Woburn and Pegwell soils (temperate region) than for Capinopolis and Janauba (tropical region). Specific respiration rate (SRR) of new biomass (from glucose) and old biomass showed different behaviors between soils. At 15ºC, the turnover C was 207, 225, 115 and 141 days for Janauba, Capinopolis, Woburn and Pegwell soil, respectively. At 35ºC, it was 92, 69, 69 and 33 days for the same soils. The residual 14C in the soil was higher at 35ºC. The final total biomasses at 15ºC and 35ºC were correlated with the initial soil carbon content. There was an average of 31 and 8 mg of biomass C.g-1 soil organic carbon, respectively at 15ºC and 35ºC. The initial carbon content was an important factor to explain the mineralization rate at 35ºC.

Saved in:
Bibliographic Details
Main Author: Vasconcellos,C.A.
Format: Digital revista
Language:English
Published: Escola Superior de Agricultura "Luiz de Queiroz" 1998
Online Access:http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90161998000100016
Tags: Add Tag
No Tags, Be the first to tag this record!