Hydrogen, carbon and sulphur isotope ratios in peat: the role of diagenessis and water regimes in reconstruction of past climates

Abstract

We demonstrate that carbon, hydrogen and sulphur isotope ratios both, in the total peat (d 13 C tp = 25.52 to 28.27‰, dD tp =78.67 and 109.24‰, d 34 S=4.35 to 19.87‰), and in cellulose from the peat (d 13 C nc =25.06 to 27.33‰ and dD nc =92.43 to 118.02‰) are not affected by postdepositional changes. Therefore, the original isotope composition of plants are in general preserved in the peat and represent an archive of the past environmental variations. These can be supported by (i) good correlations between d 13 C tp and d 13 C nc , and between dD tp and dD nc , (ii) high horizontal homogeneity of d 13 C tp and d 13 C nc in the scale of one peat-bogthe same major factor(s) control(s) C isotopic ratios, (iii) no correlation between organic sulphur concentrations and d 34 S value d 34 S results from variations in the water level.

Reconstructing climate change and ombrotrophic bog development during the last 4000years in northern Poland using biotic proxies, stable isotopes and trait-based approach

“…Even if both authors also express the need for caution in interpreting this variable, further justification for such an approach arises from a comparison study between bulk peat and cellulose d13C which demonstrated common patterns between the two datasets (Jędrysek and Skrzypek, 2005). Due to its mixed origin, bulk peat has of course several limitations compared to organic matter or cellulose carbon isotopes of specific plant parts like Sphagnum stems or branches (Loader et al, 2007;Moschen et al, 2009).…”

Isotope composition of bulk carbon in replicated Sphagnum peat cores from three Central European high-elevation wetlands

“…Typically, δ 13 C of biogenic methane can be as low as -60‰, more than 30‰ lower than that of peat substrate (see Wieder and Vitt, 2006 for a critical review). Surprisingly few studies have focused on bulk C isotope composition of the solid peat substrate (Novak et al, 1999;Jedrysek and Skrzypek, 2005). Data on δ 13 C of solid peat are needed to complement isotope signatures of the ema-…”

Carbon stable isotope analyses of mosses—comparisons of bulk organic matter and extracted nitrocellulose

“…Oxidative and hydrolytic biodegradation of this dead plant material by microorganisms (mainly fungi and bacteria) is believed to be a primary source of humic substances [10,11]. Plant cellulose is probably the most isotopically stable chemical compound, even under conditions of partial decomposition [1,[12][13][14]. Nevertheless, the primary isotopic plant composition can also be well preserved in bulk organic matter, especially in acid bog or fen conditions [14].…”

“…Plant cellulose is probably the most isotopically stable chemical compound, even under conditions of partial decomposition [1,[12][13][14]. Nevertheless, the primary isotopic plant composition can also be well preserved in bulk organic matter, especially in acid bog or fen conditions [14]. Indeed, cellulose extracted from plant and sediment is commonly used as the most reliable register of ␦ 13 C, ␦ 18 O, and ␦D isotope signals formed during photosynthesis.…”

“…About 3 to 5 mg of pure nitrocellulose or bulk plant samples were combusted with CuO wire in°a°sealed°quartz°tube,°under°vacuum°at°900°°C° [14]. The CO 2 gas produced was cryogenically purified offline (liquid nitrogen and dry ice ϩ ethanol mixture) and introduced into an isotope ratio mass spectrometer (IRMS; Finnigan-Mat Delta E/dual inlet, Bremen, Germany) for stable carbon isotope ratio analysis.…”