Diatom-based water-table reconstruction in Sphagnum peatlands of northeastern China

WATER RESEARCH

卷:174

Article

Chen, Xu¹  McGowan, Suzanne²  Bu, Zhao-Jun³  Yang, Xiang-Dong⁴  Cao, Yan-Min⁵  Bai, Xue¹  Zeng, Ling-Han²  Liang, Jia¹  Qiao, Qiang-Long¹ 

[1] China Univ Geosci, Sch Geog & Informat Engn, Hubei Key Lab Crit Zone Evolut, Wuhan 430074, Peoples R China

[2] Univ Nottingham, Sch Geog, Nottingham NG7 2RD, England

[3] Northeast Normal Univ, Inst Peat & Mire Res, State Environm Protect Key Lab Wetland Ecol & Veg, Changchun 130024, Peoples R China

[4] Chinese Acad Sci, Nanjing Inst Geog & Limnol, State Key Lab Lake Sci & Environm, Nanjing 210008, Peoples R China

[5] South Cent Univ Nationalities, Coll Resources & Environm Sci, Wuhan 430074, Peoples R China

关键词: Diatom analysis;    Transfer function;    Hydrological change;    Peat sediment;    Northeastern China;   

DOI  :  10.1016/j.watres.2020.115648

来源: Elsevier

【 摘 要 】

Peatlands are important ecosystems for biodiversity conservation, global carbon cycling and water storage. Hydrological changes due to climate variability have accelerated the degradation of global and regional ecosystem services of peatlands. Diatoms are important producers and bioindicators in wetlands, but comprehensive diatom-based inference models for palaeoenvironmental reconstruction in peatlands are scarce. To explore the use of diatoms for investigating peatland hydrological change, this study established a training set consisting of diatom composition and twelve environmental factors from 105 surface samples collected from five Sphagnum peatlands in northeastern China. Diatom communities were dominated by Eunotia species. Ordination analyses showed that depth to the water table (DWT) was the most important factor influencing diatom distribution, independently accounting for 4.99% of total variance in diatom data. Accordingly, a diatom-based DWT transfer function was developed and thoroughly tested. The results revealed that the best-performing model was based on weighted averaging with inverse deshrinking (R-2 = 0.66, RMSEP = 8.8 cm with leave-one-out cross validation). Quantitative reconstruction of DWT on a short peat core collected from the Aershan Peatland (Inner Mongolia) recorded climate-mediated hydrological changes over the last two centuries. This study presents the first diatom-water table transfer function in Sphagnum peatlands, and highlights the potential of diatoms as a powerful tool to assess the magnitude of past hydrological changes in peatlands of northeastern China, as well as similar peaty environments worldwide. (C) 2020 Elsevier Ltd. All rights reserved.

【 授权许可】

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