SEGH Articles

Multiproxy climate reconstruction from raised bog deposits along the West Coast of the British Isles

01 August 2011
Anke Kuttner was Runner up for the Springer / Hemphill Prize for Student Poster presentation at SEGH 2011 in Ormskirk, UK.

Raised peat bogs are closely coupled to the atmosphere and oceans due to their ombrotrophic state. They record variations within the peat layers and accumulate at a high rate (~5/10 years cm-1) offering reliable, high resolution palaeoenvironmental archives. Their archive records can be reconstructed using a range of techniques. In the past palaeoclimate reconstructions were commonly based on either biological or geochemical data. There are, however, problems such as preservation and mobility respectively associated with each of these techniques. Combining biological and geochemical tools can compensate for such weaknesses and help gain a more accurate picture of past palaeoclimate changes. However, few studies to date have embraced the advances of genuine multiproxy analyses.

The objective of our study conducted at the University of Aberdeen is to apply biological and geochemical proxies together to gain an improved understanding of past climate change. We aim to explore potential correlations between wet as well as dry indicators of either proxy type.

We are studying three different sites along the West coast of the British Isles with varying degrees of exposure to the North Atlantic. The first site, Tyndrain, is located in the Northwest of Wales in the Snowdonia National Park. The depth of the deposit is up to 4 m with the raised phase starting around 2.50 m. This depicts the change from minerotrophic (groundwater influence) to ombrotrophic (atmospheric influence only).

The other sites are Annaholty, a raised bog deposit in Clare, SW Ireland, and Raeburn Flow, a deposit on the Solway Firth, S Scotland.

 For biological data we look at plant macrofossils, using the Quadrat & Leaf Count technique as well as Testate amoebae specimen counts. As geochemical proxies we investigate the distribution of lithogenic versus marine derived elements as well as anthropogenic elements. Chronologies are based on 14C and 210Pb dating.


The first results for Tyndrain show that the botanical and geochemical fen-bog transition are located at different depths in the profile. The geochemical transition is distinctively higher up. We can however, pick up a big shift in all proxies around ~2800 cal BP. This coincides well with a wetshift recognisable in numerous deposits all over the world.

As for the desired correlations, we have contradicting results. However, it is possible to see some matching peaks for the various proxies in terms of wetshifts and droughts throughout the profile. An important factor influencing the distribution of lithogenic elements and their interpretation is land use.

 Our palaeoclimate reconstructions for the Tyndrain raised bog deposit show that analysing just one proxy may mask changes in bog surface wetness. However, combining biological and geochemical data can improve insight as well as raise more questions. It is therefore crucial to conduct more studies to determine consistent patterns.

Furthermore, one important denouement is that even within relatively short distances there can be high intrasite variability within peat bog ecosystems.

Anke Küttner, Dmitri Mauqouy, Tim Mighall, Eva Krupp, College of Physical Sciences, University of Aberdeen, Aberdeen, Scotland, UK.

Keep up to date

SEGH Events

Submit Content

Members can keep in touch with their colleagues through short news and events articles of interest to the SEGH community.

Science in the News

Latest on-line papers from the SEGH journal: Environmental Geochemistry and Health

  • Assessment of the toxicity of silicon nanooxide in relation to various components of the agroecosystem under the conditions of the model experiment 2018-08-18


    Investigation of SiO2 nanoparticles (NPs) effect on Eisenia fetida showed no toxic effect of the metal at a concentration of 250, 500 and 1000 mg per kg of soil, but conversely, a biomass increase from 23.5 to 29.5% (at the protein level decrease from 60 to 80%). The reaction of the earthworm organism fermentative system was expressed in the decrease in the level of superoxide dismutase (SOD) on the 14th day and in the increase in its activity to 27% on the 28th day. The catalase level (CAT) showed low activity at average element concentrations and increase by 39.4% at a dose of 1000 mg/kg. Depression of malonic dialdehyde (MDA) was established at average concentrations of 11.2% and level increase up to 9.1% at a dose of 1000 mg/kg with the prolongation of the effect up to 87.5% after 28-day exposure. The change in the microbiocenosis of the earthworm intestine was manifested by a decrease in the number of ammonifiers (by 42.01–78.9%), as well as in the number of amylolytic microorganisms (by 31.7–65.8%). When the dose of SiO2 NPs increased from 100 to 1000 mg/kg, the number of Azotobacter increased (by 8.2–22.2%), while the number of cellulose-destroying microorganisms decreased to 71.4% at a maximum dose of 1000 mg/kg. The effect of SiO2 NPs on Triticum aestivum L. was noted in the form of a slight suppression of seed germination (no more than 25%), an increase in the length of roots and aerial organs which generally resulted in an increase in plant biomass. Assessing the soil microorganisms’ complex during introduction of metal into the germination medium of Triticum aestivum L., there was noted a decrease in the ammonifiers number (by 4.7–67.6%) with a maximum value at a dose of 1000 mg/kg. The number of microorganisms using mineral nitrogen decreased by 29.5–69.5% with a simultaneous increase in the number at a dose of 50 mg/kg (+ 20%). Depending on NP dose, there was an inhibition of the microscopic fungi development by 18.1–72.7% and an increase in the number of cellulose-destroying microorganisms. For all variants of the experiment, the activity of soil enzymes of the hydrolase and oxidoreductase classes was decreased.

  • Seasonal characteristics of chemical compositions and sources identification of PM 2.5 in Zhuhai, China 2018-08-16


    Fine particulate matter is associated with adverse health effects, but exactly which characteristics of PM2.5 are responsible for this is still widely debated. We evaluated seasonal dynamics of the composition and chemical characteristics of PM2.5 in Zhuhai, China. PM2.5 characteristics at five selected sites within Zhuhai city were analyzed. Sampling began on January 10, 2015, and was conducted for 1 year. The ambient mass concentration, carbon content (organic and elemental carbon, OC and EC), level of inorganic ions, and major chemical composition of PM2.5 were also determined. Average concentrations of PM2.5 were lower than the National Ambient Air Quality Standard (NAAQS) 24-h average of 65 μg/m3. The daily PM2.5 concentration in Zhuhai city exhibited clear seasonal dynamics, with higher daily PM2.5 concentrations in autumn and winter than in spring and summer. Carbon species (OC and EC) and water-soluble ions were the primary components of the PM2.5 fraction of particles. Apart from OC and EC, chemical species in PM2.5 were mainly composed of NH4+ and SO42−. There was a marked difference between the summer and winter periods: the concentrations of OC and EC in winter were roughly 3.4 and 4.0 times than those in summer, while NH4+, SO42−, NO3, and Na+ were 3.2, 4.5, 28.0, and 5.7 times higher in winter than those in summer, respectively. The results of chemical analysis were consistent with three sources dominating PM2.5: coal combustion, biomass burning, and vehicle exhaust; road dust and construction; and from reaction of HCl and HNO3 with NH3 to form NH4Cl and NH4NO3. However, additional work is needed to improve the mass balance and to obtain the source profiles necessary to use these data for source apportionment.

  • Estimates of potential childhood lead exposure from contaminated soil using the USEPA IEUBK model in Melbourne, Australia 2018-08-14


    Soils in inner city areas internationally and in Australia have been contaminated with lead (Pb) primarily from past emissions of Pb in petrol, deteriorating exterior Pb-based paints and from industry. Children can be exposed to Pb in soil dust through ingestion and inhalation leading to elevated blood lead levels (BLLs). Currently, the contribution of soil Pb to the spatial distribution of children’s BLLs is unknown in the Melbourne metropolitan area. In this study, children’s potential BLLs were estimated from surface soil (0–2 cm) samples collected at 250 locations across the Melbourne metropolitan area using the United States Environmental Protection Agency (USEPA) Integrated Exposure Uptake Biokinetic (IEUBK) model. A dataset of 250 surface soil Pb concentrations indicate that soil Pb concentrations are highly variable but are generally elevated in the central and western portions of the Melbourne metropolitan area. The mean, median and geometric soil Pb concentrations were 193, 110 and 108 mg/kg, respectively. Approximately 20 and 4% of the soil samples exceeded the Australian HIL-A residential and HIL-C recreational soil Pb guidelines of 300 and 600 mg/kg, respectively. The IEUBK model predicted a geometric mean BLL of 2.5 ± 2.1 µg/dL (range: 1.3–22.5 µg/dL) in a hypothetical 24-month-old child with BLLs exceeding 5 and 10 µg/dL at 11.6 and 0.8% of the sampling locations, respectively. This study suggests children’s exposure to Pb contaminated surface soil could potentially be associated with low-level BLLs in some locations in the Melbourne metropolitan area.