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Geografiska Annaler: Series A, Physical Geography
ISSN: 0435-3676 (Print) 1468-0459 (Online) Journal homepage: http://www.tandfonline.com/loi/tgaa20
Late Holocene soil processes and the first
evidence for ferruginous rhizoconcretions in cool
subpolar environments of the Faroe Islands
Richard Pokorný, Kevin J. Edwards, Lukáš Krmíček, Dalibor Všianský & Petra
Veronesi Dáňová
To cite this article: Richard Pokorný, Kevin J. Edwards, Lukáš Krmíček, Dalibor Všianský &
Petra Veronesi Dáňová (2018) Late Holocene soil processes and the first evidence for ferruginous
rhizoconcretions in cool subpolar environments of the Faroe Islands, Geografiska Annaler: Series
A, Physical Geography, 100:3, 272-284, DOI: 10.1080/04353676.2018.1463142
To link to this article: https://doi.org/10.1080/04353676.2018.1463142
Published online: 18 Apr 2018.
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Late Holocene soil processes and the first evidence for ferruginous
rhizoconcretions in cool subpolar environments of the Faroe
Islands
Richard Pokorný
a,b
, Kevin J. Edwards
c,d
, LukášKrmíček
b,e,f
, Dalibor Všianský
b
and
Petra Veronesi Dáňová
a
a
Faculty of Environment, Jan Evangelista PurkyněUniversity, Ústí nad Labem, Czech Republic;
b
Department of
Geological Sciences, Faculty of Science, Masaryk University, Brno, Czech Republic;
c
Department of Geography and
Environment, School of Geosciences, University of Aberdeen, Aberdeen, UK;
d
Clare Hall, University of Cambridge,
Cambridge, UK;
e
Faculty of Civil Engineering, AdMaS Centre, Brno University of Technology, Brno, Czech Republic;
f
Institute of Geology of the Czech Academy of Sciences, Prague, Czech Republic
ABSTRACT
The Faroe Islands are characterized by high rates of Holocene
geomorphological activity and demonstrable vegetation change,
including substantial peat formation. Pedogenesis, especially in the late
Holocene, is less well known. Numerous ferruginous rhizoconcretions
consisting predominantly of Fe-oxyhydroxides were identified in loam
and silty sands in Søltuvík on the island of Sandoy, dated prior to AD
1000. Their formation is related to intensive podzolization and they take
the form of the source woody vegetation. The sub-fossil material
represents the first evidence for ferruginous rhizoconcretions in the
Faroese archipelago.
ARTICLE HISTORY
Received 1 May 2017
Revised 17 January 2018
Accepted 31 January 2018
KEYWORDS
Faroe Islands; Holocene;
pedogenesis; peat; Fe-
oxyhydroxide;
rhizoconcretion
Highlights
.Pedogenic processes in Faroese soils of the mid to later Holocene are described.
.The development of a woody plant cover is demonstrated.
.The first occurrence of ferruginous rhizoconcretions in the Faroese archipelago is proven.
1. Introduction
The Faroe Islands (61°20′N–62°24′N and 6°15′W–7°41′W; Figure 1A) are located in the North
Atlantic Ocean. The archipelago consists of 18 major islands and covers an area of around
1400 km
2
. The territory was formed by massive basalt lava flows of Palaeocene age, interbedded
with sedimentary layers of continental origin (Storey et al. 2007). The Faroes have an extremely ocea-
nic climate, with mean July/August temperatures of 11°C and mean February temperatures of 4°C;
precipitation is concentrated in winter and is around 1400 mm y
−1
close to sea level at the capital,
Tórshavn (Jóhansen 1985). The soil cover is strongly influenced by Holocene pedogenesis, with soil
types of moderate to high organic content, including peats and peaty soils (Rutherford and Taylor
1981,1982; Jóhansen 1989; Lawson et al. 2007).
© 2018 Swedish Society for Anthropology and Geography’
CONTACT Richard Pokorný richard.pokorny@ujep.cz Faculty of Environment, Jan Evangelista PurkyněUniversity, Králova
Výšina 3132/7, Ústí nad Labem CZ-400 96, Czech Republic; Department of Geological Sciences, Faculty of Science, Masaryk Uni-
versity, Kotlářská 267/2, Brno CZ-611 37, Czech Republic
GEOGRAFISKA ANNALER: SERIES A, PHYSICAL GEOGRAPHY
2018, VOL. 100, NO. 3, 272–284
https://doi.org/10.1080/04353676.2018.1463142
Faroese landscapes are characterized by an absence of trees, although prior to sustained human
settlement (c. 800 AD; Vickers et al. 2005; Olsen et al. 2010) low density wood and shrub commu-
nities were present (Hannon and Bradshaw 2000; Lawson et al. 2007,2008). Based on numerous
archaeological, palynological and entomological studies, mostly from the large islands of Streymoy,
Eysturoy, Sandoy and Suðuroy, landscape development since the Younger Dryas deglaciation (after
Figure 1. (A) Detailed aerial map of the bay at Søltuvík. The locality of rhizoconcretions is indicated by ®. (B) The Faroe Islands
archipelago. (C) The position of Faroe Islands in northern Europe (Map layers: kortal.fo, Umhvørvisstovan, Jarðfeingi).
GEOGRAFISKA ANNALER: SERIES A, PHYSICAL GEOGRAPHY 273
∼10 300 cal yr BP, Olsen et al. 2010) is reasonably well known (Buckland and Dinnin 1998; Buckland
et al. 1998a,1998b; Edwards et al. 1998; Gathorne-Hardy et al. 2007).
During a detailed palaeontological survey (Pokorný et al. 2015), ferruginous concretions in Holo-
cene soil profiles were found at the bay of Søltuvík (61°50′42.5′′ N, 6°53′36.1′′ W) on the southwest
coast of Sandoy (Figure 1B). Ferruginous concretions are known in palaeosols from many locations
(Bown 1982; Gregory et al. 2004; Kraus and Hasiotis 2006; Genise et al. 2011) and they have been
shown previously in Palaeocene deposits from Streymoy (Ellis et al. 2002). These cited instances,
however, relate to formation under warm palaeoclimatic conditions. In cool subpolar temperature
conditions, the formation of concretions mineralized by Fe-oxyhydroxides is somewhat rarer. Alho-
nen et al. (1975) mentioned their occurrence in recent soils in central and northern Finland. For Ice-
land and the Faroe Islands, such phenomena seem not to have been described (Ólafur Arnalds,
Robert J. Blakemore and Paul C. Buckland, pers. comm.). This paper presents an explanation for
the origin of the concretions within the context of ecosystem change during the Holocene.
1.1. Quaternary sedimentological and pedological contexts
The Quaternary sediments of the Faroe Islands are mostly represented by unconsolidated and weakly
consolidated glacial drift deposits associated with Weichselian glacial clays, tillites, blockfields and
aeolian sands (Rasmussen 1972; Christiansen 1998; Humlum 1998; Humlum and Christiansen
1998).
Holocene pedogenesis followed deglaciation (Lawson et al. 2005,2007), with soil formation
strongly influenced by cool and humid subpolar oceanic climatic conditions, as well as the variation
caused by differences in altitude and slope position. Rutherford and Taylor (1981,1982) described
five main soil types that are mentioned here using IUSS Working Group WRB (2015) terminology:
regosols,cambisols (brunisols), histosols,podzols and gleysols (Table 1). It is important to note that not
all Faroese soil profiles are easily classifiable and some may feature combinations of features (cf.
Edwards et al. 2005a).
2. Material and methods
2.1. Spatial settings of the study area
The coastal fringe of Sandoy is relatively flat when compared to the high cliffs which characterize
coastal areas in many of the islands in the archipelago. A slight littoral inclination of slopes towards
the sea is apparent around Søltuvík. Quaternary sediments in which soil profiles have developed are
exposed in the eroded sides of the gully which leads into the bay (Figures 1B and 4A).
Table 1. Soil types and their occurrence in the Faroe Islands (Rutherford and Taylor 1981,1982).
Soil type Texture
Average
depth
Average
altitude Conditions
Regosols Gravelly sandy loam Up to
60 cm
>300 m
a.s.l.
Associated with glacial sediments, blockfields and
aeolian deposits; usually in areas devoid of
vegetation following the removal of peat and
overgrazing by sheep
Cambisols
(brunisols)
Sandy clay loams Up to
50 cm
0–400 m
a.s.l.
In well to moderately drained areas
Histosols High organic content, often
visually homogeneous
Up to
200 cm
0–700 m
a.s.l.
In areas with heterogeneous ground moraine and
till-covered slopes adjacent to cirque floors and
U-shaped valleys
Podzols Sandy to silty loams with a
variable iron pan and a
mottled mineral layer
Up to
65 cm
<100 m
a.s.l.
On gentle slopes with till and colluvial substrates
Gleysols Sandy loams with highly organic
surface horizons
Up to
70 cm
<400 m
a.s.l.
In valleys with high water tables
274 R. POKORNÝ ET AL.
At the sampled section (Figures 2 and 4B), the uppermost 10 cm of root-penetrated, grey peaty
topsoil overlies a light grey, sandy-gravel loam of 30 cm thickness. Within this stratum, at 25–30 cm
below the surface, a distinctive zone of high Fe-oxyhydroxides is visible. An isolated piece of wood
(21 × 4 cm), identified to Larix sp. (larch, non-native), is inferred to be driftwood and was found at
the interface between the loam and the Fe-rich zone, 25 cm below the surface (Figure 3). Its radio-
carbon age is discussed below.
The sandy-gravel loam rests upon a 15-cm-thick layer of well-laminated, rusty-yellow silty sand,
probably of fluvial origin, featuring four thin (0.3–0.5 cm) yellow-grey layers with higher organic
Figure 2. The stratigraphic profile of the Quaternary sediment and soil on Søltuvík with the results of pH and TOC analysis.
Figure 3. The wood fragment (Larix sp.) found above the layer with the rhizoconcretions. The scale bar is 5 cm.
GEOGRAFISKA ANNALER: SERIES A, PHYSICAL GEOGRAPHY 275
matter content, which may be colluvial in origin. Beneath the sand layer is a black peat of 55–60 cm
thickness, containing rootlets, and which dries to a hard, brittle consistency. At 1.1 m, the peat rests
upon a thin (0.5 cm) iron pan and a basal layer of glacial diamictite. The latter is partially consoli-
dated grey tillite with weakly visible stratification. Its matrix is clayey, contains angular gravel and
cobbles. The section was excavated to a depth of 3.5 m.
Pedologically (see pH and TOC data on Figure 2), the observed soil profile as a whole is close to a
histosol (sensu IUSS Working Group WRB [2015]), although the upper part of the sequence (0–0.55
m) can be likened to a cambisol. Podzolization is also in evidence.
2.2. Field and laboratory methods
Sediment samples of 500 g weight were taken from all described layers of the profile together with
the collection of c. 20 ferruginous concretions.
For the pH and TOC analyses of the sedimentary layers, the samples were dried and sieved
through a mesh of 2 mm. A 5-ml dry sample was taken for pH analysis, mixed with 25 ml of KCl
solution and shaken for 60 min. After settling, the pH of the suspension was measured by a com-
bined electrode probe. TOC was measured on a PRIMACS Skalar autoanalyser and calculated as
the difference of total carbon (TC) obtained by burning at 1050°C in the presence of a catalyst
and inorganic carbon (IC) following reaction with 20% phosphoric acid at 105°C.
Phase and petrographic analyses of concretions were achieved by powder X-ray diffraction
(PXRD) and polarizing light microscopy. For the PXRD measurements, the sample was pulverized
and mixed with 10% fluorite (CaF
2
) used as an internal standard for the quantification of amorphous
phase content. The PXRD scan was acquired using a Panalytical Epmyrean diffractometer equipped
with a copper tube (λ
Kα
= 0.15418 nm) powered at 40 kV and 30 mA, and a Ni filter with Bragg–
Brentano reflection geometry. Step size was 0.013 °2θ, time per step was 158 s, the angular range
5–80 °2θand the total duration of the scan was 5769 s. The data were processed using Panalytical
High Score 3 Plus software. The quantitative phase analysis was accomplished with the Rietveld
method.
14
C radiocarbon dating of the fragment of Larix sp. was performed in the PoznańRadiocarbon
Laboratory (Lab. No. Poz-88954). Its age is discussed below. Dendrochronological correction was
implemented with the CALIB REV7.1.0 Radiocarbon Calibration Program and the IntCal13 cali-
bration curve (Stuiver and Reimer, 1993, Reimer et al., 2013).
Light microphotography was performed on thin sections using an Olympus BX 51 microscope.
3. Results
In the interval between the top of the Fe-rich zone to the laminated silty sands (0.25–0.55 m), fer-
ruginous concretions are frequent. They are vertical to subvertical, straight to slightly curved,
unbranched, 3–9 mm in diameter and up to 50 mm in length (Figure 4C–G). In all samples, a central
cylindrical hollow is developed, within which thin, hair-like root remnants are sporadically pre-
served. The lower end of the concretions is blunt and cone shaped. The infill of the tubular cylinders
is structureless-sand grains in a rusty-brown Fe-oxyhydroxides matrix. The walls of the central hol-
low may display root epidermis of a darker colour or only its imprint. The rhizoconcretions always
feature a well-developed upper termination and there is no visible continuation into overlying layers.
The PXRD data are summarized in Table 2. They show that the crystalline part of the ferruginous
concretions predominantly consists of anorthite and clinopyroxene, and there is a probable presence
of low amounts of haematite and quartz. About 30%
(weight)
of the sample is amorphous. The amor-
phous phase is probably formed by Fe-oxyhydroxides undetectable by PXRD due to low crystallinity.
The polished section of a rhizoconcretion sample was analysed with Raman spectroscopy to identify
the X-ray amorphous phase composition. However, no crystalline minerals except for anorthite and
clinopyroxene were identified.
276 R. POKORNÝ ET AL.
The light microphotography confirmed that the concretions consisted of partly isotropic matrix
surrounding fragments of minerals and rocks. The observed mineral composition of the sample cor-
responds to the PXRD results. The rock species are represented by basaltic rocks and less abundant
andesites. Images of a rhizoconcretion are shown in Figure 5.
Figure 4. (A) The locality of the study site at Søltuvik. (B) The soil profile from basal peats to recent topsoil. (C–G) Ferruginous
rhizoconcretions in the Fe-rich zone (C), sandy-gravel loam (D) and silty sands (E–G). The scale bar on C–Gis1cm.
GEOGRAFISKA ANNALER: SERIES A, PHYSICAL GEOGRAPHY 277
The
14
C radiocarbon age estimate for the fragment of Larix sp. found in the layer above the occur-
rence of ferruginous concretions was 940 ± 30 BP (cal. AD 1025–1160 [2σ]).
4. Discussion
4.1. Pedogenesis at Søltuvík
The glacial diamictites are probably of Weichselian age (Humlum 1998). Although the excavated
thickness at the study profile is ∼3.5 m (1.10–4.60 m), such sequences can reach ∼5 m in depth
depending on terrain and the disposition of the basal volcanic rocks.
Figure 5. Microphotographs of a rhizoconcretion sample. (A) Cross section of the whole sample (left: PPL, right: XPL, B = basaltic
rock, A = andesite, P = plagioclase/anorthite), (B) a fragment of a basaltic rock (XPL), (C) andesite fragment (XPL). Scale bar of A, B =
3 mm, C = 0.5 mm, D = 0.1 mm.
Table 2. The results of PXRD quantitative phase analysis.
Mineral %
(weight)
Na-anorthite 50.9
Clinopyroxene (augite) 18.3
Quartz? 0.3
Haematite? 0.3
Amorphous phase (=Fe-oxyhydroxide) 30.2
278 R. POKORNÝ ET AL.
In the early Holocene, the shallow, highly skeletal soils were relatively inorganic (Lawson et al.
2005,2007). They were not recognized at the study site where the soil profile starts with the peat
blanket (0.55–1.10 m); ‘blanket peat’, however, is a disputed term in Faroese mire terminology
(Edwards and Fosaa 2017). Lawson et al. (2007) concluded that peat formation in the Faroe Islands
had begun by 9000 cal. yr BP, with a possible concentration of initiation dates between c. 6000 and
4000 cal. yr BP. For the Lítlavatn area of Sandoy, an age range of 6450–6290 to 1290–1080 cal. yr BP
(2σ) was obtained (Lawson et al. 2007,2008). Given the depth of material at Søltuvík, an initiation
date at the earlier end of this spectrum might be expected.
The process of peat formation began with gradual paludification, weathering and plant cover
development. Lawson et al. (2007) considered that local topographic, hydrological and pedological
variations related to pedogenesis were more important than climate for the enactment of this process
in the Faroe Islands. Vegetation changed from fell-field communities to grasslands, tall herbs, dwarf
shrub blanket mire communities and sporadic trees or woods (Lawson et al. 2008). Although human
environmental impact over the last millennium is evident (Jóhansen 1985; McGovern et al. 1988;
Hannon and Bradshaw, 2000, Edwards et al. 2005b), ecosystems have been affected to a relatively
small degree and then mostly close to places of settlement. Human influence in encouraging the
spread of peat in the archipelago cannot be shown (Lawson et al. 2008); indeed, people have had
a negative effect upon peat development (Lawson et al. 2005, Vickers et al. 2005, Church et al. 2013).
Significant landscape development is reflected in the upper 55 cm of the Søltuvík soil profile. The
sandy-gravel loams and silty sands have analogues on Sandoy (Lawson et al. 2005) and Suðuroy
(Edwards et al. 2005a; Mairs 2007). These horizons have origins in soil development within colluvial
deposits. Edwards et al. (2005a) and Lawson et al. (2005) inferred that the last c. 3000 years were less
geomorphologically stable than the middle Holocene: lower slopes were destabilized, the extensive
lowland peat cover was disrupted and this resulted in a more varied landscape mosaic. Precise
reasons for slope-based mass movements are difficult to determine, but continuing landscape degra-
dation may have been accentuated by climatic changes or even by changing patterns in the large
colonies of nesting birds (Lawson et al. 2005). The formation of the surface capping of peaty topsoil
(0–0.10 m) may be explained by changes in local slope processes whereby there has been less ener-
getic remobilization of transported material.
4.2. Origin of the ferruginous concretions and the relevant soil processes
The occurrence of the ferruginous concretions at Søltuvík is limited to the profile section having an
increased content of Fe-oxyhydroxides (0.25–0.55 m). To explain this, it is necessary to enlist pro-
cesses associated with the origin of the ferrous materials. In the period following the major period of
peat formation, pedogenesis within the mineral soil segment of the profile would have begun. Eroded
fragments of basaltic rocks, transported from up-slope and up-valley areas, started to weather
mechanically and chemically. Fe-oxyhydroxides in the weathered basalt migrated downward
through the soil profile due to complex processes in which podzolization probably had a dominant
role (Alhonen et al. 1975, Ellis 1988, Mendelssohn et al. 1995, Veihe and Thers 2007). The intensive
leaching of Fe cations is accentuated by low base saturation and the low pH of the upper soil profiles
(Rutherford and Taylor 1981,1982).
The ferruginous concretions at Søltuvík can be explained as the pedodiagenetic mineral accumu-
lations around the plant roots, i.e. rhizoconcretions sensu stricto (Klappa 1980). Due to the absence
of specific morphological features, it is not possible to decide whether they were formed around liv-
ing or dead roots, but both possibilities might be assumed. Root growth can change the physico-
chemical conditions of the surrounding soil, producing cementation and precipitation of Fe-
oxyhydroxides in the rhizosphere through the release of polysaccharides, organic acids, electrons
and protons, packing of soil, evapotranspiration and the association with microorganisms (Violante
et al. 2003). The vertical transport of dissolved Fe-oxyhydroxides may have been accelerated by the
deep rhizosphere, with decayed root channels forming a conduit for the percolate, together with
GEOGRAFISKA ANNALER: SERIES A, PHYSICAL GEOGRAPHY 279
enhanced oxygenation. Ferruginous precipitate seems likely to have been deposited inside the chan-
nels (Kraus and Hasiotis 2006). As suggested by the slope of the diamictite and basaltic basement and
the direction of groundwater flow, the soil at Søltuvík was likely significantly moist during the
growth of the rhizoconcretions, but not saturated.
Although the occurrence of ferruginous rhizoconcretions at Søltuvík is probably explained by
podzolization as the main formation process, the local climatic and hydrological conditions suggest
that the creation of Fe (or Mn, Al) rhizoconcretions may also be associated with the anoxic soil con-
ditions in wetlands or lake fringes (cf. Mendelssohn et al. 1995). The aforementioned authors review
the biotic and abiotic processes leading to the formation of oxidized root channels and iron plaques.
As main controlling factors, they designated especially the availability of soil iron and the oxidizing
capacity of plant roots.
In his study of forest floors in British Columbia, Canada, Quesnel (1980) noted the propensity of
plants to accumulate and precipitate Fe and Al ions in the rhizosphere following preferential uptake
from physicochemical processes; the subsequent decomposition of fine roots would increase the con-
centration of Fe in the adjacent forest floor as rhizoconcretions. Alhonen et al. (1975) discussed the
formation of the concentric ring-like structure of Fe–Mn rhizoconcretions found in Finland and sta-
ted that the distribution of Fe and Mn is caused due to alternating oxidation and reduction, i.e. dry
and wet climatic cycles.
4.3. Tracemakers
Any distinctive channels aiding fluid flows in the soil profile would also assist burrowing by earth-
worms or dung beetles. However, the notion of animal origins must be rejected for the following
reasons. Earthworm traces are characterized by meniscate infill, the annulation of wall linings and
the presence of faecal pellets or aestivation chambers (Canti 2003; Verde et al. 2007; Smith et al.
2008a); structures made by dung beetles have vertical menisci, and claw marks on the inner wall
of burrows or nesting chambers are present (Retallack 1984; Genise et al. 2000; Smith et al.
2008b). These diagnostic features are missing in the observed ferruginous concretions. Moreover,
the Faroe Islands has only one species of dung beetle (Aphodius lapponum) and about 10 species
of earthworms (Lombricus terrestris and Apporectodea rosea could be envisaged due to their ethol-
ogy), and all of them are assumed to occur only since the period of settlement (Enckell and Rundgren
1983,1988; Buckland and Dinnin 1998; Buckland and Panagiotakopulu 2005). The age of the con-
cretions is estimated to pre-date human colonization.
A plant origin for the concretions would conform to the central hollow and the frequent remains
or imprints of roots on the cylinder walls. The question remains as to the exact plant species respon-
sible. At present, herbaceous vegetation with a dominance of grasses and sedges occurs over exten-
sive areas around Søltuvík. The average diameter of the rhizoconcretions reaches 5 mm, which is
markedly larger than the roots of such herb types.
There is a high probability that the root channels are the remnants of woody plants. The presence
of dwarf shrubs (mainly Calluna vulgaris), shrubs (Salix ssp., Juniperus communis) and scattered
trees (Betula pubescens) is well confirmed palaeobotanically in the Faroe Islands through the greater
part of the Holocene (Edwards et al. 2005a; Hannon et al. 2005; Lawson et al. 2005,2008; Andresen
et al. 2006; Edwards 2008).
Although the
14
C radiocarbon age for the aforementioned wood fragment was determined (cal.
AD 1025–1160), it cannot provide a certain date for the deposit in which it was located because it
is likely to be driftwood. Even if it was several decades old when emplaced, it would indicate that
the underlying rhizoconcretions pre-date ∼AD 1000. This is also supported by the fact that the rhi-
zoconcretions, including the inner hair-like root remnants, have no visible continuation into the
overlying layers. The same effect, but without the rhizoconcretions, can also be observed in the over-
lying sandy-gravel loams at depths of 0.1–0.25 m, above the zone of limonitization. It can be
explained by the growth of source plants during the formation and emplacement of the adjacent
280 R. POKORNÝ ET AL.
strata. Loosely speaking, this would not be inconsistent with the
14
C dating of soil, peat and lacus-
trine sediments at other sites on Sandoy (cf. Lawson et al. 2007,2008) and elsewhere in the Faroe
Islands, which span much of the Holocene. We would assume the Søltuvík rhizoconcretions were
formed in the mid to latter half of this period given their stratigraphic position in the profile.
5. Conclusion
The numerous ferruginous rhizoconcretions found in sandy-gravel loam and silty sands at Søltuvík
represent specific sedimentological conditions on the Faroe Islands at a date assumed to be in the
mid to later Holocene and likely prior to AD 1000. Crucial to rhizoconcretion formation was the
combination of pedogenic processes (podzolization) and a plant cover containing scattered shrubs
and trees. The sub-fossil material described here represents the first evidence for ferruginous rhizo-
concretions in the cool subpolar oceanic climate of the Faroe Islands.
Acknowledgements
The authors would like to thank Uni E. Árting (University of the Faroe Islands, Tórshavn, Faroe Islands) for admin-
istrative assistance connected with the research in the Faroe Islands; Ólafur Arnalds and Bjarni D. Sigurðsson (The
Agricultural University of Iceland) for comparative discussion on Icelandic and Faroese soils; Paul C. Buckland (Shef-
field, UK) and Robert J. Blakemore (Hanyang University, Seoul, Korea) for advice about possible tracemakers and
landscape conditions in northern Europe; V. Koutecký (Charles University in Prague, Czech Republic) for the
wood identification and LukášKraft for help with fieldwork. Thanks also belong to the PoznańRadiocarbon Labora-
tory (Poland) and especially to Thomas Goszlar for the
14
C dating and to M. Maříková (Czech Academy of Sciences,
Prague) and M. Došek (J. E. PurkyněUniversity in Ústí nad Labem) for chemical analysis.
Disclosure statement
No potential conflict of interest was reported by the authors.
Funding
This work was supported by Project of Severočeské doly a.s. [Grant Number SD-30/09/16-1]; J. E. PurkyněUniversity
Internal Grant Agency [Grant Number FŽP UJEP IG 1/2014].
Notes on contributors
Richard Pokorný is an Assistant Professor at the Jan Evangelista PurkyněUniversity, Faculty of the Environment, Ústí
nad Labem, Czech Republic. He is interested especially in ichnopaleontology in the region of Arctic and Subarctic. At
this moment, he also works on the monograph aimed at the history of coal mining in Iceland.
Kevin J. Edwards is Emeritus Professor in Physical Geography at the University of Aberdeen, United Kingdom. He has
particular interests in environmental change in the North Atlantic region and the palaeoecological basis of human–
environment interactions.
LukášKrmíček is an Associate Professor at the Brno University of Technology, Faculty of Civil Engineering, Brno,
Czech Republic. He is interested in geological processes in polar and sub-polar regions.
Dalibor Všianský is an Assistant Professor at the Masaryk University, Faculty of Science, Department of Geological
Sciences, Brno, Czech Republic. He focuses on mineralogy of silicate industrial materials and X-ray diffraction and
microscopic techniques.
Petra Veronesi Dáňová is a lab technician at the Jan Evangelista PurkyněUniversity, Faculty of the Environment, Ústí
nad Labem, Czech Republic.
ORCID
Richard Pokorný http://orcid.org/0000-0003-4639-8950
Kevin J. Edwards http://orcid.org/0000-0002-7205-066X
GEOGRAFISKA ANNALER: SERIES A, PHYSICAL GEOGRAPHY 281
LukášKrmíček http://orcid.org/0000-0003-0943-9776
Dalibor Všianský http://orcid.org/0000-0001-9769-072X
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