地质科技通报 (Mar 2021)

Seasonal variations and influencing factors of dissolved organic carbon in pore water from the Dajiuhu peatland in Shennongjia

  • Zhiqi Zhang,
  • Yiming Zhang,
  • Xianyu Huang,
  • Hua Du,
  • Jiayong Mo,
  • Wanguo Qu,
  • Ting Pi

DOI
https://doi.org/10.19509/j.cnki.dzkq.2021.0213
Journal volume & issue
Vol. 40, no. 2
pp. 147 – 155

Abstract

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Subtropical peatlands are an important component of the global peatlands and play essential roles in water regulation, carbon storage, and biodiversity.These peatlands are being subjected to the influences of global climate changes and human disturbances.Thus, it is vital to explore how the carbon dynamics of these subtropical peatlands respond to climate changes and human activities.Dissolved organic carbon (DOC) exits as labile carbon pools that are susceptive to external environmental disturbance.Under both impacts of climate change and human activities, DOC may be lost from peatlands through degradation or horizontal migration, potentially threatening the carbon storage function of peatlands.However, knowledge about the response of DOC to seasonal environmental changes in subtropical peatlands remains poor.In this study, the seasonal variations of DOC extracted from the peat porewater along a depth profile were investigated in the Dajiuhu peatland, a typical subalpine peatland in the subtropical China.Both DOC concentration and its ultra-visible (UV-Vis) spectral indices show apparently seasonal fluctuations, while some indices also display differences among depths.Correlation analysis reveals that the DOC concentration and UV-Vis indices correlate closely with the porewater conductivity and the concentration of ammoniacal nitrogen.This study demonstrates that seasonal variation is an essential phenomenon of the carbon dynamics in the Chinese subtropical peatlands.It is urgent to quantitatively evaluate how the seasonal changes affect the carbon uptake capacity and ecosystem services of the Chinese subtropical peatlands.

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