The potential and dynamics of soil carbon storage during soil development: a global synthesis of chronosequence studies
Abstract
Understanding soil organic matter dynamics is crucial for managing soil quality and predicting the interaction between climate and ecosystems. Soil C storage typically occurs after disturbances, land-use change, or emergence of new surfaces, typically in soils that have little or no soil organic matter. The disturbances may be either (1) natural - e.g., landslides, volcanic eruptions, fire, glaciation/ glacial retreat, or (2) human-induced - e.g., mining, agriculture, fire, clear-cutting, etc. The dynamics of soil organic matter accumulation in such soils is non-linear. After an initial period of rapid increase in soil C, a certain potential soil C storage is reached, after which the accumulation rate approaches zero. Although earlier studies have indicated that this initial period may last up to several thousand years, other recent studies have shown that the capacity of soils to store C may be reached much faster even in tens or hundreds of years in some systems. Soil C storage may even decrease later as the ecosystem enters a so-called retrogressive phase. The temporal changes in soil carbon storage are indicative of processes controlling C stabilization and can be evaluated using soil chronosequence data.
Here we present preliminary results of a global synthesis of chronosequence studies on soil carbon accumulation. We aim to review the overall potential of soils to store carbon and explain the different dynamics of soil C accumulation under different soil-forming conditions. Across the chronosequences included in our study, C accumulation rates range from 12 to 3048 kg ha-1 yr-1 during the first 1000 years of soil development and decrease to between <1 to 38 kg ha-1 yr-1 in soils older than 3000 years. Using these data, we explore factors controlling the soil C storage dynamics and discuss implications for land management and carbon cycle modelling.- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2018
- Bibcode:
- 2018AGUFM.B33B..07V
- Keywords:
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- 0414 Biogeochemical cycles;
- processes;
- and modeling;
- BIOGEOSCIENCESDE: 0428 Carbon cycling;
- BIOGEOSCIENCESDE: 0486 Soils/pedology;
- BIOGEOSCIENCESDE: 1630 Impacts of global change;
- GLOBAL CHANGE