thumbnail

Enhanced precipitation promotes decomposition and soil C stabilization in semiarid ecosystems, but seasonal timing of wetting matters

Plant and Soil

By:
https://doi.org/10.1007/s11104-017-3221-1

Links

Abstract

Aims

Changing precipitation regimes in semiarid ecosystems will affect the balance of soil carbon (C) input and release, but the net effect on soil C storage is unclear. We asked how changes in the amount and timing of precipitation affect litter decomposition, and soil C stabilization in semiarid ecosystems.

Methods

The study took place at a long-term (18 years) ecohydrology experiment located in Idaho. Precipitation treatments consisted of a doubling of annual precipitation (+200 mm) added either in the cold-dormant season or in the growing season. Experimental plots were planted with big sagebrush (Artemisia tridentata), or with crested wheatgrass (Agropyron cristatum). We quantified decomposition of sagebrush leaf litter, and we assessed organic soil C (SOC) in aggregates, and silt and clay fractions.

Results

We found that: (1) increased precipitation applied in the growing season consistently enhanced decomposition rates relative to the ambient treatment, and (2) precipitation applied in the dormant season enhanced soil C stabilization.

Conclusions

These data indicate that prolonged increases in precipitation can promote soil C storage in semiarid ecosystems, but only if these increases happen at times of the year when conditions allow for precipitation to promote plant C inputs rates to soil.

Additional publication details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Enhanced precipitation promotes decomposition and soil C stabilization in semiarid ecosystems, but seasonal timing of wetting matters
Series title:
Plant and Soil
DOI:
10.1007/s11104-017-3221-1
Volume:
416
Issue:
1-2
Year Published:
2017
Language:
English
Publisher:
Springer
Contributing office(s):
Forest and Rangeland Ecosystem Science Center
Description:
10 p.
First page:
427
Last page:
436