Investigation of carbon turnover and CO2 evolution in soil organic carbon from Japanese forest soils: Insight from radiocarbon analysis of soil density fractions and soil respired CO2
Abstract
Soil organic matter is important carbon reservoir managing CO2 concentration in the atmosphere. However, the mechanism of soil carbon stabilization is little known. Radiocarbon data from soil organic matter and soil respiration provide powerful constrains for determining carbon dynamics (Trumbore 2000). Here, the 14C data from six sites in Japanese forests were used to determine the turnover time. For these sites, the average age of bulk carbon above 20 cm ranges from modern to 790 yr. In each case, the average includes components such as recognizable litter fragments with much shorter turnover times, humified or mineral-associated organic matter with much longer turnover times. We sequentially density fractioned at 1.6, 1.8, 2.0, 2.2, 2.4 g cm-3 on soils to interpreted as organic matter pools with different carbon turnover times, ranging from years to decades or centuries, and different functional roles for carbon dynamic. In addition, we conducted the 14C measurement of soil respiration in a temperate forest. We will show the results and comparison of the 14C in soil respiration to indicate a contribution from decomposition of organic matter at this meeting.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2011
- Bibcode:
- 2011AGUFM.B11A0455K
- Keywords:
-
- 0428 BIOGEOSCIENCES / Carbon cycling;
- 0454 BIOGEOSCIENCES / Isotopic composition and chemistry;
- 0486 BIOGEOSCIENCES / Soils/pedology