Effects of microtopography and water table on Sphagnum palustre L. in subtropical high mountains and implications for peatland restoration

ABSTRACT

Introduction. Human disturbance has recently led to increasingly serious destruction of Sphagnum L. wetlands in subtropical high mountains, resulting in an urgent need for wetland restoration.

Methods. Through a field experiment conducted in western Hubei Province, China, the effects of four different microtopographic types [concave surface, convex surface, concave and convex surface (CC surface), and flat surface] and water table depth (0 to −30 cm) on three growth indicators (number of capitula, coverage and biomass) of Sphagnum palustre L. were examined. The objective was to identify the optimal hydrological conditions for S. palustre growth and thus facilitate its rapid recolonisation and restoration of these wetlands.

Key results. The results showed that different microtopographic conditions significantly influenced S. palustre growth. Among them, S. palustre in the CC surface showed the worst growth, while no significant differences existed among the other three microtopographic types. Additionally, as the water table increased, the growth of S. palustre increased, but long-term flooding impeded growth. The water table affected S. palustre growth via effects on its tissue water content.

Conclusions. Microtopographic reshaping was not essential for the success of S. palustre recolonisation, and microtopography that maintained the water table to within −10 cm of the surface without flooding were best, independent of the microtopographic types. In addition, the growth patterns of S. palustre changed with changes in the environment, which may be related to its long-term adaptation to conditions of a lower water table.

KEYWORDS:

• Peatlands
• Sphagnum palustre
• tissue water content
• water management
• water table
• wetland restoration

Acknowledgments

We thank Kai Tian, Binmei Xiong, Ze Li, Qianqian Peng, Yu Chen, and Shichao Li for their help with growth indicator and water table measurements; thank Qichi Yang, Yuyang Xu, and Bangjun Lin for their help with the physical and chemical analyses of the substrates, and professor Can Dai for the guidance with the statistical analysis. We also thank the Qizimei Mountains National Nature Reserve management bureau for their support, and LetPub (www.letpub.com) for linguistic assistance during the preparation of this manuscript. This experiment complies with all laws of the People’s Republic of China, where it was performed.

Notes on contributors

Ting-Ting Li is a PhD candidate who majors in botany in Hubei University.

Zheng-Xiang Wang is a professor of Hubei University whose research directions include biodiversity protection, vegetation ecology and damaged ecosystem restoration.

Gui-Jun Bu is a PhD candidate who majors in botany in Hubei University.

Li-Qun Lin is an associate professor of Hubei University whose research interests include analysis of RS image and data mining.

Yun Lei is a professor of Central China Normal University whose research is in biodiversity protection.

Chang-Yong Liu is a senior engineer in the National Nature Reserve management bureau of Qizimei Mountains, his work includes Sphagnum wetlands protection and restoration.

Lan-Fang Yang is a professor of Hubei University whose research directions are edaphology and plant nutrition.

Cheng-lin Zheng is a senior engineer in the National Park management bureau of Shennongjia, his work includes Sphagnum wetlands protection and restoration.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China 1, under Grant (number 41471041); the Technology Innovation Planning Project of Hubei Province, China 2, under Grant No. 2017ABA161; and the Open Foundation of the Hubei Key Laboratory of Regional Development and Environmental Response, China 3, under Grant No. 2017(A) 001.