 |
| Titel |
An Integrated Analysis of Soil Incubation Data: Deriving Soil Type Dependent Moisture-Respiration Relations |
| VerfasserIn |
Fernando Moyano, Claire Chenu |
| Konferenz |
EGU General Assembly 2011
|
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 13 (2011) |
| Datensatznummer |
250058037
|
|
|
|
|
|
| Zusammenfassung |
| One of the most important factors affecting soil carbon mineralization is soil moisture. The
general relation between moisture and soil microbial activity is well known, with
many publications on the topic throughout the last decades. Soil respiration is at a
minimum at very low and very high moisture levels, limited either by mobility and
osmotic potential effects or by a lack of oxygen. Moisture-respiration relations are
integrated into all widely used soil carbon dynamics models. However, models
such as Century and Roth-C apply only one moisture function to all soil types.
The reason for this is that, despite the amount of related studies, little information
is available on the variations of these moisture effects across soil types. Limited
knowledge in this area, with related uncertainties in models, could lead to widely
wrong predictions of soil carbon stock changes. With this study we aim at finding,
on the one hand, general dependencies across soils describing variations of the
moisture-respiration relation, and on the other hand, information as to what studies are
necessary to advance our understanding in this area by identifying soil types or
moisture conditions which are not well characterized. Soil incubations under controlled
conditions are well suited for obtaining precise relationships between variables,
avoiding the confounding effects commonly found in field studies. To explore relations
between moisture effects on decomposition of organic matter and a number of soil
characteristics, we compiled data on soil incubations from both published and unpublished
sources where soil moisture was varied and measured. Values of respiration, moisture,
temperature, texture, carbon and nitrogen content, and pH are available for most of the
obtained data-sets. Since different units and incubation conditions characterize each of
the data-sets, a prerequisite was to process and normalize the data from different
sources for this study. In the next step, currently being carried out, we look for
relations between soil characteristics and the moisture effects on respiration that
can be applied to a range of (non-waterlogged) soils. We expect such findings to
ultimately lead to improvements in the performance and predictive power of soil
models. |
|
|
|
|
|
|