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Fossil remains of the mycorrhizal fungal Glomus fasciculatum complex in postglacial lake sediments from Maine

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R. Scott Anderson at Northern Arizona University
R. Scott Anderson
Richard L. Homola
Richard L. Homola
Richard L. Homola
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Ronald B. Davis at University of Maine
Ronald B. Davis
George L. Jacobson at University of Maine
George L. Jacobson
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Abstract

Specimens of the vesicular–arbuscular mycorrhizal fungal Glomus fasciculatum complex have been identified from lake sediment cores from Gould Pond (central Maine) and Upper South Branch Pond (north central Maine). The fungus became established with tundra vegetation on newly developing soils soon after the melting of Wisconsin ice. This is the first record of such an occurrence for North America. The earliest specimens from Gould Pond were deposited in sediment dated at about 13 000 years old and those at Upper South Branch Pond between about 12 500 and 11 000 years old. This is at least 1000 years prior to the arrival of trees in those areas. Sedimentologic and biologic evidence indicates soil instability and relatively high soil erosion rates from the watersheds during the late-glacial period. Thus erosion probably accounts for the abundance of Glomus in late-glacial sediments. The reduced abundance of the fungus in Holocene sediments is attributed to a decrease in the rate of soil erosion after the establishment of trees.
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Fossil remains of the mycorrhizal fungal
Glomus fasciculatum
complex in postglacial
lake sediments from Maine'
R. Scorr ANDERSON'
Department of Botany and Plant Pathology and lrlstit~lte ,fi)r Quclternary Studies, Ur~ive~sity of Maine,
Orono, ME, U.S.A.
04469
RICHARD L. HOMOLA
Department
qj'
Botany and Plarlr Pathology, University oJ'Maine, Orono. ME, U.S.A.
04469
AND
RONALD B. DAVIS
AND
GEORGE L. JACOBSON, JR.
Department
of Botany and Plant Pathology and lrl.sriture for Quaterrlclry Studies, University uf Maine,
Orono, ME. U.S.A.
04469
Received January 3, 1984
ANDERSON,
R. S., R. L.
HOMOLA,
R. B.
DAVIS,
and G. L.
JACOBSON,
JR.
1984. Fossil remains of the mycorrhizal fungal
C1omu.s fa.sciculaturn
complex in postglacial lake sediments from Maine. Can.
J.
Bot.
62:
232552328,
Specimens of the vesicular-arbuscular mycorrhizal fungal
C1otnu.s fascicuk~rum
complex have been identified from lake
sediment cores from Gould Pond (central Maine) and Upper South Branch Pond (north central Maine). The fungus became
established with tundra vegetation on newly developing soils soon after the melting of Wisconsin ice. This is the first record
of such an occurrence for North America. The earliest specimens from Gould Pond were deposited in sediment dated at about
13 000 years old and those at Upper South Branch Pond between about 12 500 and
I
I
000 years
old.
This is at least 1000 years
prior to the arrival of trees in those areas. Sedimentologic and biologic evidence
indicates
soil instability and relatively high
soil erosion rates from the watersheds during the late-glacial period. Thus erosion probably accounts for the abundance of
G1omu.s
in late-glacial sediments. The reduced abundance of the fungus in Holocene sediments is attributed to a decrease in
the rate of soil erosion after the establishment of trees.
ANDERSON,
R. S., R. L.
HOMOLA,
R. B.
DAVIS
et G. L.
JACOBSON, JR.
1984. Fossil remains of the mycorrhizal fungal
Clornlls
fa.sciculnrum
complex in postglacial lake sediments from Maine. Can.
J.
Bot.
62:
2325-2328.
En examinant des carottes de sediments lacustres provenant de Gould Pond (Maine central) et du Upper South Branch Pond
(Maine centre-nord), les auteurs ont identifiC des spCcimens du complexe
Clotnus fir.sciculaf~cn~,
champignons formant des
endomycorhizes
a
vCsicules et arbuscules. Les champignon s'est Ctabli avec la vCgCtation de toundra sur les sols en formation,
peu aprks la disparition des glaces du Wisconsin.
I1
s'agit de la prcmikre mention d'une telle prCsence en AmCrique du nord.
Les spCcimens les plus anciens
it
Gould Pond ont CtC dCposCs dans le sCdiment
il
y a cnviron 13 000 ans, et ceux de Upper
South Branch Pond, entre 12 500 et l
l
000 ans. Ceci Ctait au moins 1000 ans avant I'arrivCe des arbres dans ces rCgions. Les
donnCes ~Cdimentologiques et biologiques indiquent la prCsence d'une instabilite du sol et d'unc erosion du sol relativement
importante dans ces bassins hydrographiques pendant la fin de la pCriode glaciaire. Ainsi
il
est probable que I'abondance des
Glomus
dans les sCdiments tardi-glaciaires soit like
a
I'Crosion. La diminution dans I'abondance du champignon dans les
sCdiments de I'holocknc est attribuCe
a
une diminution dans le taux d'krosion du sol
lie
a
['apparition des arbres.
[Traduit par le journal]
Introduction
The symbiotic relationships between plants and mycorrhizal
fungi are now recognized to be important to the health and
productivity of many plant taxa. Under certain conditions my-
corrhizae may enhance growth (Gerdemann 1968), protect the
host plant from pathogens (Marx 1972), or both. Vesicular-
arbuscular (VA) mycorrhizae (endomycorrhizae) of genera
such as
Glomus
are found in association with a great variety of
cultivated plants and plants of natural forest communities.
These relationships are undoubtedly not recent in origin (Butler
1939; Malloch et al. 1980; Wagner and Taylor 1981). How-
ever, there is little evidence that indicates how quickly mycor-
rhizal plants became established in developing postglacial soils
which initially consisted of barren glacial deposits, open to
colonization by many forms of biota.
Lake sediments usually contain fossils that provide detailed
'A contribution of the Institute for Quaternary Studies, University
of Maine, Orono, ME, U.S.A. 04469.
'Present address: Department of Geosciences, Laboratory of
Paleoenvironmental Studies, University of Arizona, Tucson, AZ,
U.S.A. 85721.
evidence about the past characteristics of the lake water, vege-
tation and soils of the watershed, and the interactions of vege-
tation and environment. We have been examining lake sedi-
ments of Upper South Branch Pond (hereafter called USBP),
located at 46'5'
N
by 68'54' W in north central Maine, and
Gould Pond, 44'44' N by 69'19' W in central Maine (Fig. I),
to deduce the characteristics of the vegetation and abiotic envi-
ronment surrounding the lakes in former times.
The sediments of both lakes contain fossil fungal hyphae
and, although fungal hyphae and spores are commonly found
in lake and wetland sediments (see for example, Bradbury
1978; Birks 198
1
;
Tolonen 1983), late-glacial and postglacial
fossil mycorrhizal fungi from North American sediments are
rarely identified and reported (for European reports see van
Gee1 1978; van Gee1 et al. 1980). Such reports from North
America have been limited to localities in Alberta (Butler
1939), Minnesota (Rosendahl 1943), North Carolina (Wolf
1969), and New York (Miller 1973). We report here on the
occurrence of specimens of the vesicular-arbuscular fungus,
Glomus fasciculatum
(Thaxter sensu Gerdemann) Gerdemann
and Trappe complex, in ancient sediments from the two local-
ities in Maine.
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2326
CAN.
J.
BOT.
VOL.
62,
1984
FIG.
I.
Locations of Upper South Branch Pond (Pd.) and Gould
Pond. ME.
Methods
Sediment cores were collected with a modified Livingstone piston
coring apparatus (Livingstone 1955). Subsamples of the sediment
cores used for macrofossil analysis were first disaggregated in dilute
KOH
solution (USBP) or in distilled water (Gould Pond). The slurry
was then washed gently through a series of sieves and collected on a
180 pm mesh sieve. Until examined, the macrofossils were stored in
either a Formalin solution (USBP) or ethyl alcohol (Gould Pond).
Specimens of the fungus selected for photography were then mounted
in 70% alcohol.
Results
Specimens of the fossil fungus from either six (USBP) or
seven (Gould Pond) levels were examined. The specimens
included both chlamydospores and hyphae (Figs. 2 and 3).
Chlamydospores occurred in loose aggregations or in small,
compact clusters of 4 to 27. The chlamydospores are sub-
globose to globose, with diameters of 52
X
67 to 100
x
125 pm. Two separate walls are evident in these specimens.
The outer thick wall is smooth, has adhering debris, occa-
sionally appears irregularly pitted, and is yellow-brown in
color. The inner membranous wall is thinner and lighter in
color. The hyphal attachment is ca. 7 pm in diameter, with a
wall near the chlamydospore attachment ca. 4 pm thick and
yellow-brown in color.
A difference in interpretation of G. fasciculatum exists
among taxonomic specialists of the Endogonaceae (Gerdemann
and Trappe 1974; Trappe 1982; S. Berch, personal commu-
nication). The fungus from the two Maine locations has been
identified as belonging to the G. fasciculatum group
(J.
Trappe,
personal communication; Trappe 1982). It is possible that more
than one species is involved. Because of this uncertainty, we
have used the term "Glomus fasciculatum complex."
The fossil Glomus fasciculatum complex material from
Gould Pond was recovered from sediment deposited between
ca. 13 000 years BP and ca. 10 900 years BP. The USBP
samples came from sediment deposited between ca. 12 500 and
ca. 10 200 years BP. Nonarboreal pollen types, such as wil-
FIG. 2. Fossil members of the
Glomus fasciculat~tm
complex,
Upper South Branch Pond, ME, lake sediment. Chlamydospores and
hyphae. Ca. 142~.
FIG. 3. Fossil member of the
Glomus fnsciculatum
complex,
Upper South Branch Pond, ME, lake sediment. Chlamydospore
enlargement. Ca. 700x.
lows (Salix spp.), sedges (Cyperaceae), grasses (Gramineae),
and other herbs, attained maximum postglacial values during
these time periods (Anderson and Davis 1980; Anderson et al.
1982). Vaccinium uliginosum and Dryas integrifolia plant mac-
rofossils are found in many of the same sediment subsamples
as the fungus, as well as contiguous subsamples. Macrofossils
of arboreal species, beginning with spruce (Picen), are found
in sediment deposited after ca. 10 800 years BP at Gould Pond
and ca. 10 400 years BP at USBP. Tree remains dominated the
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ANDERSON
ET
AL.
2327
macrofossil assemblages throughout the Holocene.
Glomus
fasciculatum
complex specimens are found only at widely
spaced intervals (ca. 9000, 7700, 6500, 4000, and 100 years
BP) in USBP Holocene sediments and are not found in
Holocene sediments from Gould Pond.
Discussion
Fossil mycorrhizal fungi recovered from late-Quaternary
sediments were first reported by Butler (1939) as species of
Rhizophagus
Dang. from glaciolacustrine and peaty sediments
("muskeg") near Edmonton, Alta., Canada. Later, Rosendahl
(1943) described two slightly differing species from Minnesota
(Bronson, Jackson, and Moorhead sites):
Rhizophagites butleri
Rosendahl (vesicles light brown, 75
X
79 to 103
x
124 pm)
and
R.
rninnesotensis
Rosendahl (vesicles dark brown, 42
X
46
to 58
x
6
1
pm). Wolf (1969) recovered
Endogone (Rhizo-
phagus)
in peaty lake sediment from New Bern, NC. Miller
(1973) described
Rhizophagites butleri
from glacial Lake
Iroquois sediments in Lockport, NY. Later, Gerdemann and
Trappe (1974) placed
R. butleri
in synonymy with
Glomus
fasciculatum.
Although none of the above specimens was found conclu-
sively in organic connection with other plant materials, infor-
mation on associated fossil plants is available for all specimens.
Only the Alberta specimens remain undated.
Picea-Larix
bog
remains (Bronson and Jackson sites) and boreal forest litter
deposits (Moorhead site) are associated with the Minnesota
fungi (Rosendahl 1948). Radiocarbon dates on these materials
have been reported as follows: Bronson site, greater than
36 000 years BP (Flint and Rubin 1955); Moorhead site,
9930
t
280 years BP (Wright and Rubin 1956). On strati-
graphic grounds, the Jackson, MN, material is no less than
13 700 years old (Denton and Hughes 1981). The Lockport,
NY, fungus, dated at about 12 000 years BP, was associated
with plants from a wide variety of habitats, and the vegetation
was interpreted as being similar to boreal forest. No associated
plants were reported for the ca. 24 000 year old North Carolina
materials (Wolf 1969), but D. A. Livingstone (personal com-
munication) suggested a forest association there also.
Members of the
Glomus fasciculatum
complex are known to
occur naturally with a wide variety of plant species character-
istic of temperate and boreal forest ecosystems (Gerdemann
and Trappe 1974); as mentioned above, the fossil specimens in
the previous studies were found in association with plants char-
acteristic of such environments. Unnamed VA endomycor-
rhizae have also been reported from modern tundra soils near
Barrow, AK (Miller and Laursen 1978). These authors found
an association with several members of the Ranunculaceae,
Gramineae, Cyperaceae, and
Saxifraga
and with at least one
moss,
Pogonatum.
However, the occurrence of members of the
G. fascirulatum
complex in the lowest sections of the two
Maine cores is significant because it is the first known occur-
rence of the fungus deposited with late-glacial tundra plant
assemblages from North America. Pollen and macrofossils
from sediment levels containing the fungus, and from adjacent
core intervals, suggest that during this period of tundra around
Gould Pond and USBP, sedges (Cyperaceae) and grasses
(Gramineae) were common along with, at USBP,
Oxyria
digyna
(L.) Hill and
Arenaria rossii
Richards. (Anderson and
Davis 1980; Anderson et al. 1982).
Saxifraga
pollen was
recovered from Gould Pond sediments (R. S. Anderson,
unpublished data). The most common dwarf shrubs included
Dryas integrifolia
M. Vahl,
Salix
spp.
(S. herbacea
L. and
S. uva-ursi
Pursh at USBP),
Vaccirzium
cf.
uliginosum
and
V.
cf.
vitis-idaea. Pogonatum alpinum
(Hedw.) Rohl. grew
around USBP, along with at least two species of arctic-alpine
mosses,
Didymodon asperifolius
(Mitt.) Crum, Steere and
Anders. and
Aulacomnium turgidum
(Wahl.) Schwaegr.
(N. Miller, personal communication). No macrofossils of trees
were found in sediments deposited during the tundra period.
From macrofossil evidence, spruce did not grow around
Gould Pond until ca. 10 800 years BP and USBP until
ca. 10 400 years BP. The fungi were present in soils for at least
1000 years before the arrival of tree species.
The only sporadic occurrence of specimens of the
Glomus
fasciculatum
complex in posttundra sediments of USBP and the
absence of the fungus in posttundra sediments of Gould Pond
are best explained by the stabilization of soils and subsequent
decrease in erosion around the lakes, following the establish-
ment of arboreal species. The lake sediments deposited during
the tundra period contain higher percentages of inorganic
matter derived from the terrestrial environment, indicating that
soils were probably less stable during the tundra period than in
later times. The 41 samples of late-glacial tundra sediments at
USBP average 97.4% inorganic matter, whereas the 153 sam-
ples of Holocene sediments average 78.0% inorganic matter.
At Gould Pond, the 19 samples of late-glacial tundra sediments
average 97.2% inorganic matter, while the 45 samples of
Holocene sediments average 77.3% inorganic matter. A link
between establishment of trees and a decrease in de~osition of
inorganic matter has also been suggested for Mirror Lake, NH,
by Davis and Ford (1982), who found that the postglacial
arrival of
Picea
in the region coincided with a precipitous
decline in rates of inorganic accumulation within the basin.
In addition to sedimentary indicators of landscape insta-
bility, early successional mosses that colonize bare rock
(Grimmia
sp.,
Arctoa- Kiaeria
sp.,
Andreaea rothii
Web.
&
Mohr) and mineral soil
(Ceratodon purpureus
(Hedw.) Brid.,
Pogonatum alpinum
(Hedw.) Rohl.,
Polytrichum
sp.) are com-
mon at USBP (N. Miller, personal c.ommunication). These
species occur as fossil only in the sediments deposited during
the tundra period. Based on pollen evidence, Spear (1981)
suggested that periglacial frost activity on the White Mountains
of New Hampshire during the late-glacial period contributed to
landscape instability. This would have provided continuously
fresh mineral surfaces near the lakes. The periglacial frost
hypothesis is strengthened if relict periglacial features are
found within the area.
Acknowledgements
We thank Dr. James M. Trappe for tentative identification of
the fossil specimens of
Glomus fasciculatum;
Dr. Norton G.
Miller for sharing unpublished information on the fossil fungi
from Lockport, NY, and fossil mosses and
Arenaria
from
USBP, ME; and Dr. Robert Stuckenrath, for the radiocarbon
dates on sediment from the two Maine lakes. This work was
supported, in part, by a Sigma Xi grant-in-aid of research to
R. S. Anderson, and by National Science Foundation grant
DEB 8004171 to G. L. Jacobson, Jr., and R. B. Davis.
ANDERSON,
R.
S., and
R.
B. DAVIS. 1980. Late- and postglacial
vegetational history at Upper South Branch Pond
in
northern
Maine. Sixth Biennial Meeting, AMQUA, Orono, ME, U.S.A.
p.
5.
(Abstr.)
ANDERSON,
R.
S.,
G.
L.
JACOBSON,
JR., and
R.
B. DAVIS. 1982.
Late- and postglacial environmental change
in
central Maine: a
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2328
CAN.
J.
BOT.
VOL.
62,
1984
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... • Livestock grazing and other human activities are more prevalent in river valleys compared to mountain forests and subalpine meadows [14]. Due to this, it is common to see the transfer of spores of AM fungi through human shoes and livestock hooves (such as cows and horses) [49,107]. However, some evidence indicates that ungulate grazing may be associated with decreased AM fungal abundance in soil [23]. ...
... However, some evidence indicates that ungulate grazing may be associated with decreased AM fungal abundance in soil [23]. Additionally, AMF spores can migrate with water flows from the mountains to the river valley during erosions [107][108][109], and they actively enter into nonspecific symbiotic relationships after sedimentation. Despite the fact that the organic reserves in these ecosystems are much higher because of livestock grazing, the ecosystems themselves may have signs of soil degradation and are considered disturbed. ...
Diversity of Arbuscular Mycorrhizal Fungi in Distinct Ecosystems of the North Caucasus, a Temperate Biodiversity Hotspot
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Background: Investigations that are focused on arbuscular mycorrhizal fungus (AMF) biodiversity is still limited. The analysis of the AMF taxa in the North Caucasus, a temperate biodiversity hotspot, used to be limited to the genus level. This study aimed to define the AMF biodiversity at the species level in the North Caucasus biotopes. Methods: The molecular genetic identification of fungi was carried out with ITS1 and ITS2 regions as barcodes via sequencing using Illumina MiSeq, the analysis of phylogenetic trees for individual genera, and searches for operational taxonomic units (OTUs) with identification at the species level. Sequences from MaarjAM and NCBI GenBank were used as references. Results: We analyzed >10 million reads in soil samples for three biotopes to estimate fungal biodiversity. Briefly, 50 AMF species belonging to 20 genera were registered. The total number of the AM fungus OTUs for the “Subalpine Meadow” biotope was 171/131, that for “Forest” was 117/60, and that for “River Valley” was 296/221 based on ITS1/ITS2 data. The total number of the AM fungus species (except for virtual taxa) for the “Subalpine Meadow” biotope was 24/19, that for “Forest” was 22/13, and that for “River Valley” was 28/24 based on ITS1/ITS2 data. Greater AMF diversity, as well as number of OTUs and species, in comparison with that of forest biotopes, characterized valley biotopes (disturbed ecosystems; grasslands). The correlation coefficient between “Percentage of annual plants” and “Glomeromycota total reads” r = 0.76 and 0.81 for ITS1 and ITS2, respectively, and the correlation coefficient between “Percentage of annual plants” and “OTUs number (for total species)” was r = 0.67 and 0.77 for ITS1 and ITS2, respectively. Conclusion: High AMF biodiversity for the river valley can be associated with a higher percentage of annual plants in these biotopes and the active development of restorative successional processes.
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... 1) Human activity (livestock grazing, etc.) is much more developed in river valleys than in mountain forests and subalpine meadows [12]. The invasion of AM fungi by transferring spores on human shoes and hooves of livestock (cows, horses, etc.) is quite common [48,103]. However, some evidances indicate that ungulate grazing may be associated with the decrease of AM fungal abundance in soil [21]. ...
... However, some evidances indicate that ungulate grazing may be associated with the decrease of AM fungal abundance in soil [21]. Along with that AMF spores can migrate with water flows from the mountains to the river valley during erosion [103][104][105] and after sedimentation it actively enter into nonspecific symbiotic relationship. It is developed despite the fact that the organic reserves in these ecosystems are much higher because of livestock grazing, moreover the ecosystems themselves may have signs of soil degradation and are considered to be disturbed. ...
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Preprint
Full-text available
  • Dec 2023
Background: Number of investigations, which are focused on arbuscular mycorrhiza fungi (AMF) biodiversity is still limited. The analysis of AMF taxa in the North Caucasus, a temperate biodiversity hotspot, used to be limited by the genera level. The aim of this study was to define AMF biodiversity at the species level in the North Caucasus biotopes. Methods: Molecular genetic identification of fungi was carried out with ITS1 and ITS2 regions as barcodes, sequencing by Illumina MiSeq, analysis of phylogenetic trees for individual genera, searching the operational taxonomic units (OTUs) with identification at the species level. Sequences from MaarjAM and NCBI GenBank were used as references. Results: We analyzed >10 million reads in soil samples for 3 biotopes to estimate fungal biodiversity. 50 AMF species from 20 genera were found. The valley biotopes (disturbed ecosystems, grasslands) were characterized by a greater AMF diversity, as well as the number of OTUs and species, in comparison with the forest biotopes. Conclusion: Our hypothesis is that high AMF biodiversity for the river valley can be associated with a higher percentage of annual plants in these biotopes, as well as with the active development of restorative successional processes.
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... Furthermore, the presence of Glomus during this period suggests erosion activity. Glomus is a type of mycorrhizal fungus commonly associated with plant roots, and its presence in the sediment record can indicate the transport and deposition of eroded material (Anderson et al., 2011). Pseudoschizaea is a type of algal spore that belongs to the group known as Concentricystes (Milanesi et al., 2006). ...
... The observation of Glomus, a soil erosion indicator, in the levels where Cathaya, Tsuga, and Carya appear supports the idea of sediment reworking. Glomus is known to be associated with soil erosion processes (Anderson et al., 2011), and its presence in the sediment layers containing reworked plant taxa suggests that these taxa might have been transported from older sediment layers and deposited during the study period. ...
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... They rarely produce hard resistant tissues thus not prone to fossilization, however their spores, hyphae and fruit bodies are preserved as organic matter and can be isolated using palynological maceration techniques [53]. A comprehensive account of the diverse aspects of Palaeomycology which includes study of fossil fungal palynomorphs their morphology, descriptive terminology, identification and nomenclature, geological history and paleoenvironmental and paleoclimatic significance, etc. is discussed [53,56]. Fungi provides evidence for relative humidity, atmospheric pressure, and precipitation rates. ...
Source and Distribution of Palynomorphs in Southern Red Sea Coastal Environments of Saudi Arabia: Their Palaeoenvironmental and Palaeoecological Inferences
Preprint
Full-text available
  • Jun 2024
Palynomorph assemblages and mineral microfossils from five southern Red Sea coastal environments were studied to demonstrate their distribution pattern and suggest their source. The environments studied were 1. mangrove swamp 2. middle Holocene paleochannel 3. algal mat, 4. Sabia Island coral reef, and intertidal zone. The samples studied were from the top 3 cm semi-consolidated sediments from various environments. Standard palynological maceration technique was used to isolate palynomorphs. These sediment samples are mainly clay and fine sand and yielded low numbers but high diversity of palynomorph assemblages. They are grouped into pollen and spores, dinoflagellate cysts, and algal remains, fungal spores, hyphae and fruit bodies, protists, and invertebrates. A few Ascidian and sponge spicules, and phytoliths (mineral microfossils) occur in the Sabia Island coral reef environment. The protists and invertebrate remain include microforaminifera, thecamoebians, tintinnomorphs, crustacean and annelid palynomorphs. The assemblage also includes six form taxa belonging to the form genera Katora and Mangrovia. These palynomorphs belong to both marine and terrestrial environments and are of autochthonous and allochthonous origins. The source and genetic relationship of each palynomorphs is discussed.
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... Glomus is known to be the largest genus of mycorrhizal, and their abundance was reported to increase with increasing grazing intensity (Lorenzo and Havrylenko, 2001;Wang, 2021). In addition, Glomus has been used in paleoecological studies to indicate increased soil erosion, reduced vegetation cover, and human activity in lake catchments (Anderson et al., 2011;Hillbrand et al., 2012Mighall et al., 2012Van Geel et al., 1989). The indicative value of HdV-104 remains unclear, and the abundance of this type increases with grazing intensity, which may also be related to indirect mechanisms of grazing. ...
Indication of coprophilous fungal spores for monitoring grazing intensity in the Horqin Sandy Land, Northern China
Article
  • Jun 2024
  • PROG PHYS GEOG
Coprophilous fungal spores are an emerging and potential proxies for indicating the long-term pastoral history. However, the indication of coprophilous fungal spores for dung and grazing intensity remains uncertain. In this study, in Horqin Sandy Land, 27 livestock dung samples and 33 surface soil samples were collected, and the indication of coprophilous fungal spores was discussed for the first time. The results showed that a total of 38 fungal spore types were recognized in the modern samples from the Horqin Sandy Land, including seven coprophilous fungal spore types. The coprophilous fungi assemblages vary in different dung types and may enable the diagnosis of specific livestock taxa. Coprophilous fungal spores, especially Sporormiella and Podospora are the most reliable dung indicators and can indicate the presence of herbivores. Moreover, some fungal spores, including Helminthosporium, Apiosordaria, HdV-104, and Glomus A were also potential indicators of grazing activities in the Horqin Sandy Land. On this basis, the concentration of coprophilous fungal spores may have the potential to be a quantitative indicator of grazing intensity. This study clarifies the indication of coprophilous fungal spores on dung and grazing intensity in the Horqin Sandy Land and provides a theoretical reference for further research on pastoral history in the region.
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... The occurrence of Glomus during this period implies the occurrence of erosion activity. Glomus is a mycorrhizal fungus commonly found in association with plant roots, and its presence in the sediment record suggests the transportation and deposition of eroded materials (Anderson et al. 1984). Pseudoschizaea are algal spores, also known as the Concentricystes group, and may indicate soil erosion, does Glomus (Milanesi et al. 2006). ...
Exploring pre‑neolithic environmental dynamics: paleoecology around the Göbekli Tepe based on a multiproxy approach in southeastern Türkiye
Article
Full-text available
  • Feb 2024
  • PLANT SOIL
Paleoecological findings from soil samples recovered near the Göbekli Tepe indicate an environment that sustains a variety of multiproxy analyses, revealing prominent changes in ecological conditions. Soil samples were collected in the vicinity of the pre-Neolithic site in the Göbekli Tepe. These sediment samples underwent comprehensive analysis utilizing a multiproxy approach, which included pollen analysis, total organic carbon (TOC) and total inorganic carbon (TOC) measurements, and X-ray fluorescence (XRF) elemental analysis. Total organic carbon varied significantly in the SK-1 section, with lower levels at the bottom and higher levels at the top. The Ca/Ti ratio, which is indicative of weathering and moisture availability, typically increased in the early Holocene and briefly decreased at approximately 13,354 years BP. The Sr/Ti ratio, related to weathering and erosion processes, also suggests intensified weathering. The presence of deciduous forests and the increase in organic carbon values further support the notion of favorable environmental conditions during the early Holocene. In contrast, the lower levels of SK-1 show lower organic carbon values, lower Ca/Ti and Sr/Ti ratios, and greater abundances of herbaceous plants and steppes, indicating colder and drier conditions at 13,354 years BP. A significant increase in organic carbon values and the presence of deciduous Quercus in the upper levels of the SK-3 section suggest a period of increased organic productivity and the existence of deciduous forests during the early Holocene at the Göbekli Tepe.
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... The Late Medieval burning events also coincide with higher values of grazing and erosion indicators, like Chlamydospores of the mycorrhizal fungi Glomus sp. (Anderson et al. 1984) and coprophilous fungal spores (e.g., Sporormiella, Sordaria-types) (Perrotti and van Asperen 2019). These low-intensity fires occurred regularly in a landscape that was deeply impacted by intensive agro-pastoral activities up to the mid-14th century (detected peak at 653 − 591 cal bp; ad 1244-1381, Fig. 2). ...
The role of fire in the Medieval and Early Modern landscape of Bad Waldsee within the broader context of the pre-Alpine forelands of south-western Germany
Article
Full-text available
  • Dec 2023
  • VEG HIST ARCHAEOBOT
Fire, an important element of human land use strategies, was part of many early industrial activities but also of burning incidents that significantly impacted settlement structures and development. The spatial proximity of the historically well-documented medieval town and sediment archive deposited in its central lake (Stadtsee) was taken to investigate the interplay of fire and socio-environmental developments during the preindustrial phase of 750−150 bp (ad 1200–1800). The burning episodes were detected using the sediment macroscopic charcoal record (> 150 μm) and were interpreted considering sedimentological, palynological, and historical evidence. Macro-charcoal analysis revealed two main phases of biomass burning: a late Medieval one (653−533 cal bp ), followed by a distinct fire-free interval, and a second Modern Times phase (313 cal bp until today). During the late Medieval times and after ad 1750 (200 cal bp) low-magnitude local fires coincided with high-intensity land use pressure. Major historical events like the Thirty Years’ War and the fire incident near the town (ad 1386, 174 cal bp) were also documented by the charcoal sedimentary record. The specific terrain morphology and the town microclimate impacted the chance of whether certain local burning patterns were detectable at all. This study demonstrates that during the Medieval period to the present day, fire events, mainly anthropogenic, were coupled with the main vegetation developments. Anthropogenic fire was an inseparable part of the Bad Waldsee landscape, as also recorded historically by the town archives.
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... A greater soil erosion and contribution of allochthonous detrital materials is observed in the last centuries, interpreted from the increase in Glomus endomycorrhizal fungus in the LS sediment samples (Fig. 4). The abundance of Glomus in paleoecological records has been related to enhanced rates of soil erosion and other mechanical soil disturbances (Anderson et al., 1984;Van Geel et al., 1989), which could also be related to recent human impact in the LS area. The previous sedimentological study of the LS sedimentary sequence shows a significant increase in organic content and a change in the C/N in the last ~500 years that was interpreted as an anthropically-forced seasonal lake eutrophication and/or soil erosion in the catchment area . ...
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... The presence of common Glomus sp. spores, which also have high dispersal efficiency, might suggest increased erosion maybe due to anthropogenic disturbances (Anderson et al., 1984;Neumann et al., 2014). ...
Modern pollen-and phytolith - vegetation relationships at a wetland in northeastern South Africa
Article
  • Sep 2023
  • S AFR J BOT
Inpalaeoenvironmentalreconstructions,fewstudieshavefocusedoncomparingthepresenceofpollenandphytolithsinsurfacesedimentstothelocalvegetation.Notwithstandinginherentdifferentialpollenandphytolithpreservation,production,anddispersal,whichaffecttheirrecoveryandinterpretationinsedimentarchives,thereremainsaneedtoexploremodernpollen-vegetation,phytolith-vegetationandpollen-phyto-lithrelationshipstoimprovepalaeoenvironmentalreconstructions.Wecarriedoutpalynologicalandphyto-lithanalysisonsixsurfacesedimentsampleslinkedtothebotanicalsurveyoffivevegetationsurveyplotsatGustavKlingbielNatureReserve,MpumalangaprovinceinnortheasternSouthAfrica,tounderstandtherela-tionshipsbetweenthemodernpollenandphytolithassemblagesinthesurfacesedimentsandthecontem-poraryvegetationofthestudyarea.CorrespondenceAnalysis(CA)wasundertakentoexaminethefingerprintofthelocalvegetationinthemodernpollen-phytolithassemblageandevaluatewhetherthephy-tolithandpollenassemblagesweretrackingeachother.CAillustratedthatpollenandphytolithproxiesarenottrackingthesameprimaryvegetationsignals;modernpollenassemblagesbestrepresentthecompo-nentsofforestandwetlandvegetation.Incontrast,modernphytolithassemblagesbestrepresentgrasslandvegetation.Ourstudyshowsthatdifferentialpollenandphytolithpreservation,productionanddispersalsig-nificantlyaffectsedimentrecordsmorethananticipated,thuscombiningmulti-proxies(e.g.,phytoliths,pol-len)providesamoreaccuratebasisfortheinterpretationoffossilspectrainpalaeoenvironmentalreconstructions.
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Methodological Hints
Chapter
  • May 2024
The paleoecological study of Lake Montcortès began in 2004 with the first coring campaign of its varved sediments. In the first instance, these sediments were 14C dated and analyzed palynologically at low resolution (centennial). Further studies based on varve counting provided a detailed yearly chronology that allowed the development of high-resolution reconstructions of a diversity of proxies, including pollen and spores, covering the last 3000 years. The palynological reconstruction disclosed in this book is based on a composite sequence using cores from 2004 and further coring campaigns, with an average resolution of ~16 years (decadal to bidecadal). Core sampling, sample processing, and pollen analysis were conducted using standard methods, and the interpretation was based on a two-year modern-analog study of pollen sedimentation using sediment traps. These studies provided information useful for paleoecological and paleoclimatic reconstruction, such as bulk annual pollen sedimentation, seasonal patterns, and the relationship between sedimentary pollen and the main meteorological variables. Overall, pine and oak pollen were dominant (>75% of pollen assemblage), followed by Cannabis, grasses, and other herbs. These pollen types varied seasonally, defining two well-differentiated assemblages corresponding to spring/summer and fall/winter. Significant correlations were found among these pollen assemblages and meteorological parameters such as temperature, precipitation, relative humidity, and wind intensity/direction.
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Ecto- and Endomycorrhizae of Arctic Plants at Barrow, Alaska
Chapter
  • Jan 1978
The increased growth and dependence of many green plants on the presence of mycorrhizae has long been known and appreciated by biologists (Marks and Kozlowski, 1973). The early research dealt with ectomycorrhizal fungi and a series of experiments clearly indicated that greater uptake of nitrogen and phosphorus from infertile soils occurred when mycorrhizae were present. Nutritional studies of selected mycorrhizal fungi by Palmer and Hacskaylo (1970) indicated that most of these fungi utilized simple sugars most efficiently. In fact, they were unable to degrade lignin, cellulose, pectin, and other complex carbohydrates. This nutritional mode contrasted sharply with the typical fungal decomposers which possess this ability along with a faster growth rate and the ability to grow on a wide variety of natural and artificial substrates. In 1965, Lewis and Harley first described the one-way movement of carbohydrates from host roots to the mycorrhizal fungus. In this process sugar is converted by the fungus to trehelose and mannitol and eventually to the storage polysaccharide, glycogen. The host plant cannot utilize these sugars. Bevege, et al. (1975) confirmed this phenomenon with Pinus radiata and Rhizopogon luteolus. They reported the same process in the endomycorrhizal hyphae of Endogone but only a minute amount of sugar was incorporated by the fungus. The difference seems to lie in the ability of the ectomycorrhizal fungus to act as a nutrient sink. Nevertheless, both fungal-root associations have the overall effect of increasing plant growth dramatically.
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Radiocarbon Dates of Pre-Mankato Events inEastern and Central North America
Article
  • May 1955
1) A group of samples from horizons previously correlated with the upper part of the Cary substage confirms the correlation as reasonable and is consistently related in time to the dates of the peat layer at Two Creeks and subsequent Mankato events. 2) A major glaciation affected the Great Lakes region beginning 25,000 or more yr ago and reaching its maximum extent about 18,000 yr ago. It is represented by drift correlated in Ohio with the Cary substage and, at least in part, with the Tazewell substage; in Illinois and adjacent states it is correlated with most of the Tazewell substage and with the Farmdale loess. 3) The ecology and other associations implied by the dated samples are more consistent with glacial than with nonglacial conditions. 4) The lower till at Sidney, Ohio (W-188), on which is developed a soil considered a correlative of the Fox series soil on gravels and also buried by till of the major glaciation of 25,000 to 18,000 yr ago, indicates an earlier glaciation extensively exposed in Ohio and believed to be an early Wisconsin event. Table 2. List of samples and dates arranged by age groups. [See table in the PDF file] 5) An earlier glaciation, or glaciations, is implied at several localities by peat, gyttja, or wood more than 30,000 yr old, overlain by till. 6) The time interval between the middle group and the old group of samples, which has been determined within conservative radiocarbon limits to be greater than 3000 yr, is possibly of the order of 16,000 yr, as suggested by the depth of leaching at Sidney, Ohio.(The ages of all the samples discussed are listed in Table 2.) 7) An attempt should now be made to fix more closely the dates of the old samples and to reexamine in the field the stratigraphic sequence in the light of the radiocarbon dates discussed.
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