Role of recent climate change on carbon sequestration in peatland systems

Abstract

Highlights 6• Mean rates of carbon accumulation since 1850 were 11.26 t ± 0.68 t CO2e ha −1 yr −1 for 7 valley mire and 11.77 t ± 0.88 t CO2e ha −1 yr −1 for blanket bog 8 • Contemporary rate of CO2 sequestration was 9.13 t ± 0.98 t CO2e ha −1 yr −1 9• Past and contemporary peatland carbon sinks were found to be at the upper limits of 10 those reported in the literature 11 • Recent changes in climate appear to have had minimal impact on the strength of 12 peatland carbon sinks in South West England 13 Abstract 14 This paper provides information on the impact of recent climate change on carbon 15 sequestration in peatland systems in South West England. This is important because 16 peatlands have the potential to sequester and hold large quantities of anthropogenically 17 released CO2. This paper investigates whether there has been a reduction in the strength of 18 carbon sinks in a valley mire and blanket bog; which occur on the limits of the 19 biogeographical envelop for peatlands in Britain. Past rates of carbon accumulation were 20 determined from peat depth and the sequential analysis of peat age, bulk density and carbon 21 content from cores taken from valley mire and blanket bog. At the valley mire site 22 contemporary net ecosystem carbon balance (NECB) was calculated by measuring inputs to the peat body, via net primary productivity (NPP), of Sphagna. Losses of C from the peat 24 body were calculated by measuring CH4, and aquatic carbon; calculated from catchment 25 export of particulate and dissolved organic carbon. The study found similar mean rates of 26 carbon accumulation since 1850 of 11.26 t ± 0.68 t CO2e ha −1 yr −1 (307 g C m −2 yr −1 ) in 27 valley mire and 11.77 t ± 0.88 t CO2e ha −1 yr −1 (321 g C m −2 yr −1 ) in blanket bog. The mean 28 present-day CO2 sequestration rate for Sphagna on valley mire was calculated to be 29 9.13 t ± 0.98 t CO2e ha −1 yr −1 (249 g C m −2 yr −1 ). Both past and contemporary rates of CO2 30 sequestration were found to be at the upper limits of those reported in the literature for 31 temperate peatlands. NPP was found to vary according to microform with higher rates of 32 carbon sequestration found in lawn and hummock microforms compared with pools. Our 33 work suggests that recent changes in the climate appear to have had limited impact on the 34 strength of peatland carbon sinks in South West England. 35 Key Words 36 CO2 sequestration; peatlands; Sphagnum; net ecosystem carbon balance; climate change; peat 37 accumulation 38 The authors use the term net ecosystem carbon balance (NECB), as defined in Chapin et al., 39 (2006) to describe carbon uptake in peatlands. All values for carbon are presented as CO2 40 equivalents (t CO2e ha −1 yr −1 ), where carbon (C) is converted to CO2 based on molecular 41 mass difference by multiplying the amount of C by 3.667. Where values are cited from the 42 literature the original units are reported, along with converted values in t CO2e ha −1 yr −1 for 43 comparison. 'Carbon accumulation' refers to carbon accumulated as peat. The...

Peatland initiation in Central European Russia during the Holocene: Effect of climate conditions and fires

“…Peatland development and their possible responses to environmental changes and human impact during the Holocene are a key focus of palaeoecological studies due to the very important role of peatlands in the global carbon cycle (Charman et al, 2013, 2015; Feurdean et al, 2019; Lunt et al, 2019; Mauquoy and Yeloff, 2008; Payne et al, 2016; Turetsky et al, 2015; Yu, 2006, 2011). Boreal and arctic peatlands occupy large areas of the Earth and act as an especially important natural carbon sink as plants remove carbon dioxide from the atmosphere and incorporate the carbon into organic matter.…”

“…During the last several decades numerous studies analysed carbon accumulation rates in peatlands during the Holocene in regions of Northern America and Eurasia; however, the main drivers of peat initiation as well as the age of peatland inception have not been thoroughly investigated and remain an important challenge (Camill et al, 2009; Charman et al, 2013, 2015; Kirpotin et al, 2007; Loisel et al, 2014; Lunt et al, 2019; Yu, 2012). Recently published basal radiocarbon dates from peatlands in the Northern Hemisphere indicate that most northern peatlands rapidly expanded between 12,000 and 8000 cal yr BP (Dendievel et al, 2020; Korhola et al, 2010; MacDonald et al, 2006; Morris at al., 2018; Yu, 2012; Zhao et al, 2014).…”

Field detection of urease and carbonic anhydrase activity using rapid and economical tests to assess microbially induced carbonate precipitation

“…A simple and economical test to detect enzymatic activity in the field may also help us understand the microbial processes that contribute to the chemistry and mineralogy of poorly studied sites. For example, though calcareous fens and other peatland ecosystems are extensive in some regions and are relevant carbon sinks (Lunt et al ., 2019), little information exists about the activity of their microbial communities, in particular the activity of urease. We showed here not only that calcareous fen microbes have the potential to express urease, but also that their urease is active in situ in certain environments, where urease‐driven MICP could occur.…”

Warming Increases the Carbon Sequestration Capacity of Picea schrenkiana in the Tianshan Mountains, China

“…Forest carbon sequestration in mountainous regions could provide crucial data for understanding the role of the carbon cycle in regional and global climate changes [43]. Carbon sequestration capacity has usually been investigated based on direct field measurements [23,[44][45][46][47] or process-based terrestrial biosphere models [48][49][50][51]. In the current study, however, existing forest carbon sequestration of the Tianshan Mountains was estimated using data from national forest inventory or direct field measurements [22,23,29,52,53].…”