Elsevier

Ecological Engineering

Volume 147, 15 March 2020, 105760
Ecological Engineering

Impacts of coppicing on Tamarix chinensis growth and carbon stocks in coastal wetlands in northern China

https://doi.org/10.1016/j.ecoleng.2020.105760Get rights and content

Abstract

Coppicing is a highly effective method of producing a great deal of fast growing, sustainable timber without the need for replanting. Tamarix chinensis, a native salt-tolerant species, plays an important role in the ecosystems of arid saline alkali soil and coastal wetlands in northern China. In this study, we conducted a coppicing field experiment on T. chinensis to study the vigor of resprouting over a 4-year monitoring period in the coastal wetland of Laizhou Bay, China. Results of this study show that the growth of coppiced T. chinensis was vigorous and conformed to an “S-curve” type growth pattern. The height and crown of coppiced T. chinensis recovered quickly to the initial level by the 2nd year of regrowth and its aboveground biomass regained 93.5% of the previous level by the 4th year. The carbon stock in the T. chinensis wetland was significantly increased by the coppicing operation. Carbon stocks in the aboveground parts and soil (0–100 cm) increased by 222.6 g m−2 and 588.9 g m−2, respectively, during the 4-year experimental period. These values are 43% and 74% higher, respectively, than those in the control plot over the same period. These results indicate that coppicing provides a practical means for promoting regeneration and rejuvenation of Tamarix spp. forests as well as a new approach to increasing biomass and carbon stocks in the coastal wetlands of northern China.

Introduction

Coastal wetlands serve a vital role in the global carbon cycle. Thus, it is important to understand the impacts of wetland creation on the function and formation of carbon stocks (Chmura et al., 2003; Marín-Muñiz et al., 2014). With increasing concerns about the impacts of climate change, interest in the role of plants as potential carbon sinks for removing and storing atmospheric carbon has been growing (Sardans and Peñuelas, 2012, Sardans and Peñuelas, 2013). Wetland biomass management is a key objective of wetland ecological restoration and management (Whitcraft et al., 2008; Dang et al., 2017). Increasing vegetation biomass is an effective way to increase carbon sequestration in coastal wetlands (Chen et al., 2012).

Resprouting is a common means of clonal growth for many woody plants in which biomass is generated without sacrifice of the current generation of roots (Bellingham and Sparrow, 2000). Resprouting is likewise an efficient mechanism by which plants regain aboveground biomass immediately after disturbance (e.g., coppicing, fire, hurricane, or browsing), thereby maximizing the long-term mean biomass occupancy rate of the site (Tredici, 2001; Lawes and Clarke, 2011; Tanentzap et al., 2012). Coppice management is an ancient practice of forest management that involves repetitive felling of growth on the same stump, near to ground level, and allowing the shoots to regrow from the cut stumps of the previous stand (Kruger and Reich, 1993; Lawes and Clarke, 2011; Mosseler et al., 2014). For some fast-growing trees (e.g., poplars, willows and oaks), coppicing is a highly effective method of producing a great deal of fast growing, sustainable timber without the need to replant (Mosseler et al., 2016; Spinelli et al., 2017). Coppicing has been practiced for hundreds of years in many European temperate forests to meet the demand for wood resources (e.g., Pietras et al., 2016; Oliveira et al., 2018). In particular, this management style affects forest vegetation dynamics (e.g., competition and growth patterns), root systems, and decomposition conditions in coppiced forests, whose characteristics are remarkably different from those of undisturbed forests (Kruger and Reich, 1993; Verlinden et al., 2015; Spinelli et al., 2017; Oliveira et al., 2018). Estimating the growth and carbon stock of biomass under coppice management has been a major area of research interest (Kneifl et al., 2015; Stolarski et al., 2018). Coppicing characteristics, plant physiological traits and plant size are likely determinants of the resprouting vigor of individual shrubs (Pelc et al., 2011; Hmielowski et al., 2014; Isogimi et al., 2014; Verlinden et al., 2015). For many shrub species, vegetative resprouting after topkilling disturbance leads to regrowth of greater biomass than was initially lost (Hoffmann and Solbrig, 2003; Briggs et al., 2005; Lopez-Pintor et al., 2006). Resprouted stems increase biomass production compared with undisturbed stems of the same species, through higher photosynthetic rates and a greater abundance of photosynthetic tissues (Kruger and Reich, 1993; Huang et al., 2007). Genetic and environmental effects on the production of above-ground biomass in short rotation coppice forests have been previously documented in Europe (Benetka et al., 2014), including under Mediterranean conditions (Oliveira et al., 2018). Moreover, it has been reported that Corylus americana exhibited more vigorous responses to coppicing in open sunlit conditions than in shaded sites, while increased coppicing frequency reduced resprouted biomass in both habitats (Pelc et al., 2011).

Tamarix spp. (Tamarix chinensis, Tamarix ramosissima, or their hybrids), a salt-tolerant shrub, occurs as a native species in the northwestern arid regions of China (e.g., Xinjiang Province and Inner Mongolia Province) and in the coastal wetlands of the Yellow River Delta (He et al., 2016). These species are also found in the western United States of America, where they are considered an alien invasive species (Whitcraft et al., 2008). As the major woody plant of the coastal wetland in northern China, Tamarix chinensis has received special attention in the context of coastal wetland ecological restoration and protection (Liu et al., 2014; Zhang and Chen, 2015; Wang et al., 2016b; Xie et al., 2017). Although coppicing technology of T. chinensis has been successfully used in the Ejin oasis in the west of Inner Mongolia (Zhao et al., 2013), it has not been applied to coastal wetlands. Here, we conducted a coppicing experiment and monitored the growth of coppiced T. chinensis for 4 years in T. chinensis coastal wetlands to study the effect of the coppicing operations on T. chinensis growth and carbon stock in the coastal wetland, including both the above-ground and soil organic carbon stock.

Section snippets

Geographical setting

The National Marine Ecology Special Protected Area of Changyi, located to the south of Laizhou Bay in Shandong Province, is the largest coastal wetland in northern China containing Tamarix chinensis as the dominant vegetation (Fig. 1). The local climate is a typical temperate continental monsoon climate with an annual average temperature of 11.9 °C, and a mean annual precipitation of 628.6 mm. The rainfall in July–August contributes 52% of the total annual precipitation. The average annual

Vegetation and soil properties in the field trial before coppicing

In the field trial, T. chinensis was the only shrub and the dominant herbs were A. capillaris and Cynanchum chinense. The height of T. chinensis ranged from 1.32–3.24 m with an average of 2.15 m. The crown width and base diameter of most T. chinensis were less than 4 m2 and 6 cm, respectively. The aboveground dry weight of T. chinensis was less than 2 kg plant−1 for approximately 71.2% of samples. The density of T. chinensis ranged from 0.12 to 1.44 plants m−2 with an average of 0.35 plants m−2

Factors affecting the number of respouting branches

Coppicing greatly increased the number of branches per stool. The numbers of branches increased from 1 to 5 branches per stool before coppicing to ~35 sprouted branches per stool within the first growth year. That is because coppicing removes apical dominance and permits the development of secondary buds (Liu et al., 2011; Finnan et al., 2016). However, due to self-thinning, the number of sprouted branches reduced in the following years. Branch mortality occurred mostly among the smallest

Conclusions

Quantifying the resprouting growth of woody shrubs is an important factor in understanding the ecology and management of many ecosystems, particularly those developed on saline alkali soils and coastal wetlands, where deep-rooted shrubs are dominant. Our results indicate that the application of coppicing operations to T. chinensis in a coastal wetland was successful. All the coppiced T. chinensis resprouted in the following spring without any shrub death, and the growth of the coppiced T.

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgments

The authors are grateful to all laboratory members for their support and/or assistance with our research, particularly Mingzhu Fu, Ying Wang, and Kan Chen. This work was financially supported by the National Natural Science Foundation of China -Shandong Join Fund (Grant Nos.U1606404 and U1706217) and the National Marine Public Welfare Research Project of China (No.201205008). We thank Alex Boon, PhD, and Guy Evans, PhD, from Liwen Bianji, Edanz Editing China (www.liwenbianji.cn/ac), for editing

References (69)

  • T. Isogimi et al.

    Species-specific sprouting pattern in two dioecious Lindera shrubs: the role of physiological integration

    Flora

    (2014)
  • T. Kaipainen et al.

    Managing carbon sinks by changing rotation length in European forests

    Environ. Sci. Pol.

    (2004)
  • X. Liu et al.

    Soil organic carbon, carbon fractions and nutrients as affected by land use in semi-arid region of Loess Plateau of China

    Pedosphere

    (2010)
  • Z. Liu et al.

    Influence of thinning time and density on sprout development, biomass production and energy stocks of sawtooth oak stumps

    For. Ecol. Manag.

    (2011)
  • J.H. Liu et al.

    Effects of salt-drought stress on growth and physiobiochemical characteristics of Tamarix chinensis seedlings

    Sci. World J.

    (2014)
  • A. Lopez-Pintor et al.

    Shrubs as a source of spatial heterogeneity - the case of Retama sphaerocarpa in Mediterranean pastures of central Spain

    Acta Oecol.

    (2006)
  • A. Mosseler et al.

    Allometric relationships in coppice biomass production for two north American willows (Salix spp.) across three different sites

    For. Ecol. Manag.

    (2014)
  • A. Mosseler et al.

    Allometric relationships from coppice structure of seven North American willow (Salix) species

    Biomass and Bioenergy

    (2016)
  • E.N. Mwavu et al.

    Sprouting of woody species following cutting and tree-fall in a lowland semi-deciduous tropical rainforest, North-Western Uganda

    Forest Ecol. Manage.

    (2008)
  • N. Oliveira et al.

    Above- and below-ground carbon accumulation and biomass allocation in poplar short rotation plantations under Mediterranean conditions

    For. Ecol. Manag.

    (2018)
  • X. Pan et al.

    Polychlorinated naphthalenes (PCNs) in riverine and marine sediments of the Laizhou Bay area, North China

    Environ. Pollut.

    (2011)
  • B.D. Pelc et al.

    Frequency and timing of stem removal influence Corylus americana resprout vigor in oak savanna

    Forest Ecol. Manag.

    (2011)
  • M. Prada et al.

    Carbon sequestration for different management alternatives in sweet chestnut coppice in northern Spain

    J. Clean. Prod.

    (2016)
  • L. Quevedo et al.

    Selective thinning of Arbutus unedo coppices following fire: Effects on growth at the individual and plot level

    For. Ecol. Manag.

    (2013)
  • M.J. Stolarski et al.

    Short rotation coppices, grasses and other herbaceous crops: Biomass properties versus 26 genotypes and harvest time

    Ind. Crop. Prod.

    (2018)
  • I. Strubelt et al.

    Inter-annual variation in species composition and richness after coppicing in a restored coppice-with-standards forest

    For. Ecol. Manag.

    (2019)
  • M.S. Verlinden et al.

    Net ecosystem production and carbon balance of an SRC poplar plantation during its first rotation

    Biomass Bioenergy

    (2013)
  • M.S. Verlinden et al.

    First vs. second rotation of a poplar short rotation coppice: Above-ground biomass productivity and shoot dynamics

    Biomass Bioenergy

    (2015)
  • Y. Yao et al.

    Effects of shrubs on soil nutrients and enzymatic activities over a 0–100 cm soil profile in the desert-loess transition zone

    Catena

    (2019)
  • R.J. Bellingham et al.

    Resprouting as a life history strategy in woody plant communities

    Oikos

    (2000)
  • V. Benetka et al.

    Biomass production of Populus nigra L. clones grown in short rotation coppice systems in three different environments over four rotations

    iForest

    (2014)
  • G. Berhongaray et al.

    Soil carbon and belowground carbon balance of a short-rotation coppice: assessments t from three different approaches

    GCB Bioenergy

    (2017)
  • J.M. Briggs et al.

    An Ecosystem in transition: causes and consequences of the conversion of mesic grassland to shrubland

    Bioscience

    (2005)
  • L. Cao et al.

    Geochemical characteristics of soil C, N, P, and their stoichiometrical significance in the coastal wetlands of Laizhou Bay, Bohai Sea

    CLEAN – Soil Air Water

    (2015)
  • Cited by (10)

    View all citing articles on Scopus
    View full text