Partitioning of respired CO₂ in newly sprouted Moso bamboo culms

Front Plant Sci. 2023 Apr 20:14:1154232. doi: 10.3389/fpls.2023.1154232. eCollection 2023.

Authors

Chongyu Ye^{1

2

3}, Qiangfa Zeng^{1

2

3}, Keda Hu³, Dongming Fang⁴, Dirk Hölscher⁵, Huaqiang Du^{1

2

3}, Yongjun Shi^{1

2

3}, Yufeng Zhou^{1

2

3}, Frank Berninger⁶, Tingting Mei^{1

2

3}, Guomo Zhou^{1

2

3}

Affiliations

¹ State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Lin'an, Zhejiang, China.
² Key Laboratory of Carbon Cycling in Forest Ecosystems and Carbon Sequestration of Zhejiang Province, Zhejiang A&F University, Lin'an, Zhejiang, China.
³ College of Environmental and Resource Sciences, Zhejiang A&F University, Lin'an, Zhejiang, China.
⁴ Jiyang College, Zhejiang A&F University, Zhuji, Zhejiang, China.
⁵ Tropical Silviculture and Forest Ecology, University of Göttingen, Göttingen, Germany.
⁶ Department of Environmental and Biological Sciences, University of Eastern Finland, Joensuu, Finland.

Abstract

Stem respiration (R _s) plays a vital role in ecosystem carbon cycling. However, the measured efflux on the stem surface (E _s) is not always in situ R _s but only part of it. A previously proposed mass balance framework (MBF) attempted to explore the multiple partitioning pathways of R _s, including sap-flow-transported and internal storage of R _s, in addition to E _s. This study proposed stem photosynthesis as an additional partitioning pathway to the MBF. Correspondingly, a double-chamber apparatus was designed and applied on newly sprouted Moso bamboo (Phyllostachys edulis) in leafless and leaved stages. R _s of newly sprouted bamboo were twice as high in the leafless stage (7.41 ± 2.66 μmol m^-2 s^-1) than in the leaved stage (3.47 ± 2.43 μmol m^-2 s^-1). E _s accounted for ~80% of R _s, while sap flow may take away ~2% of R _s in both leafless and leaved stages. Culm photosynthesis accounted for ~9% and 13% of R _s, respectively. Carbon sequestration from culm photosynthesis accounted for approximately 2% of the aboveground bamboo biomass in the leafless stage. High culm photosynthesis but low sap flow during the leafless stage and vice versa during the leaved stage make bamboo an outstanding choice for exploring the MBF.

Keywords: explosive growth; leaf phenology; sap flow; stem photosynthesis; stem respiration.

Grants and funding

The research was supported by the National Nature Science Foundation of China (grant number: 32001102), Zhejiang Provincial Natural Science Foundation (grant number: Q19C160022), the Key Research and Development Program of Zhejiang Province (2021C02005), Scientific Research Foundation of Zhejiang A&F University (grant number: 2020FR050), Scientific Research Foundation of Jiyang College of Zhejiang A&F University (grant number: 05251700038), Overseas Expertise Introduction Project for Discipline Innovation (111 Project D18008).