Dataset Information

Soil aggregates indirectly influence litter carbon storage and release through soil pH in the highly alkaline soils of north China.

ABSTRACT:

Background

Soil aggregate-size classes, structural units of soil, are the important factors regulating soil organic carbon (SOC) turnover. However, the processes of litter C mineralization and storage in different aggregates-size classes are poorly understood, especially in the highly alkaline soils of north China. Here, we ask how four different aggregate sizes influence rates of C release (C_r) and SOC storage (C_s) in response to three types of plant litter added to an un-grazed natural grassland.

Methods

Highly alkaline soil samples were separated into four dry aggregate classes of different sizes (2-4, 1-2, 0.25-1, and <0.25 mm). Three types of dry dead plant litter (leaf, stem, and all standing dead aboveground litter) of Leymus chinensis were added to each of the four aggregate class samples. Litter mass loss rate, C_r, and C_s were measured periodically during the 56-day incubation.

Results

The results showed that the mass loss in 1-2 mm aggregates was significantly greater than that in other size classes of soil aggregates on both day 28 and day 56. Macro-aggregates (1-2 mm) had the highest C_r of all treatments, whereas 0.25-1 mm aggregates had the lowest. In addition, a significant negative relationship was found between C_s/C_r and soil pH. After incubation for 28 and 56 days, the C_s was also highest in the 1-2 mm aggregates, which implied that the macro-aggregates had not only a higher CO₂ release capacity, but also a greater litter C storage capacity than the micro-aggregates in the highly alkaline soils of north China.

SUBMITTER: Yang C

PROVIDER: S-EPMC6824446 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Soil aggregates indirectly influence litter carbon storage and release through soil pH in the highly alkaline soils of north China.

Yang Chao C Li Jingjing J Zhang Yingjun Y

PeerJ 20191029

<h4>Background</h4>Soil aggregate-size classes, structural units of soil, are the important factors regulating soil organic carbon (SOC) turnover. However, the processes of litter C mineralization and storage in different aggregates-size classes are poorly understood, especially in the highly alkaline soils of north China. Here, we ask how four different aggregate sizes influence rates of C release (C<sub>r</sub>) and SOC storage (C<sub>s</sub>) in response to three types of plant litter added t ...[more]

PMID: 31687276

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Dataset Information

Soil aggregates indirectly influence litter carbon storage and release through soil pH in the highly alkaline soils of north China.

Background

Methods

Results

Publications

Soil aggregates indirectly influence litter carbon storage and release through soil pH in the highly alkaline soils of north China.

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