Revealing horizontal and vertical variation of soil organic carbon, soil total nitrogen and C:N ratio in subtropical forests of southeastern China

Jiaqi Dong; Kangning Zhou; Peikun Jiang; Jiasen Wu; Weijun Fu

doi:10.1016/j.jenvman.2021.112483

Revealing horizontal and vertical variation of soil organic carbon, soil total nitrogen and C:N ratio in subtropical forests of southeastern China

J Environ Manage. 2021 Jul 1:289:112483. doi: 10.1016/j.jenvman.2021.112483. Epub 2021 Mar 31.

Authors

Jiaqi Dong¹, Kangning Zhou¹, Peikun Jiang², Jiasen Wu², Weijun Fu³

Affiliations

¹ State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Lin'an, 311300, China; Zhejiang Provincial Key Laboratory of Carbon Cycling in Forest Ecosystems and Carbon Sequestration, Zhejiang A&F University, Lin'an, 311300, China.
² State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Lin'an, 311300, China.
³ State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Lin'an, 311300, China; Zhejiang Provincial Key Laboratory of Carbon Cycling in Forest Ecosystems and Carbon Sequestration, Zhejiang A&F University, Lin'an, 311300, China. Electronic address: fuweijun@zafu.edu.cn.

PMID: 33812147
DOI: 10.1016/j.jenvman.2021.112483

Abstract

Soil organic carbon (SOC) and total nitrogen (STN) are crucial soil quality indicators in a forest ecosystem. Their cycling processes and interactions have a key impact on the plants productivity, potential carbon sequestration and stability of the terrestrial ecosystem. In this study, soil profile samples (0-100 cm) were collected from 906 plots of typical subtropical forest in Zhejiang Province, southeastern China. Moran's I, geostatistics and geographic information system (GIS) techniques were used to study the vertical and horizontal heterogeneity of SOC, STN and C:N ratio. The results indicated that the contents of SOC and STN clearly decreased with the soil depth increasing (from 0 to 10 cm layer to 60-100 cm layer). The spatial distributions of SOC and STN were consistent with the topography, showing a decreasing trend from southwest to northeast of Zhejiang Province. The results of ANOVA and correlation analyses indicated that the dominant tree species, elevation and Normalized Difference Vegetation Index (NDVI) were the key factors affecting SOC and STN contents. For the total 0-100 cm soil layer, the mean densities of SOC and STN were 108.53 Mg ha^-1 and 0.08 Mg ha^-1, respectively. The total stocks of SOC and STN were 877.19 Tg and 84.42 Tg. Approximately 65% SOC and 45% STN were belonged to the upper 30 cm soil layer, which was strongly related to the actual soil thickness. The results could provide critical information for forestry and environmental management related to C and N accumulations in subtropical forests of China.

Keywords: Carbon and nitrogen density; Environmental variables; Forest soils; GIS; Spatial variation.

MeSH terms

Carbon* / analysis
China
Ecosystem
Forests
Nitrogen / analysis
Soil*

Substances

Soil
Carbon
Nitrogen