TY  - GEN
A1  - Hodgkins, Suzanne B.
A1  - Richardson, Curtis J.
A1  - Dommain, René
A1  - Wang, Hongjun
A1  - Glaser, Paul H.
A1  - Verbeke, Brittany
A1  - Winkler, B. Rose
A1  - Cobb, Alexander R.
A1  - Rich, Virginia I.
A1  - Missilmani, Malak
A1  - Flanagan, Neal
A1  - Ho, Mengchi
A1  - Hoyt, Alison M.
A1  - Harvey, Charles F.
A1  - Vining, S. Rose
A1  - Hough, Moira A.
A1  - Moore, Tim R.
A1  - Richard, Pierre J. H.
A1  - De La Cruz, Florentino B.
A1  - Toufaily, Joumana
A1  - Hamdan, Rasha
A1  - Cooper, William T.
A1  - Chanton, Jeffrey P.
T1  - Tropical peatland carbon storage linked to global latitudinal trends in peat recalcitrance
T2  - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe
N2  - Peatlands represent large terrestrial carbon banks. Given that most peat accumulates in boreal regions, where low temperatures and water saturation preserve organic matter, the existence of peat in (sub)tropical regions remains enigmatic. Here we examined peat and plant chemistry across a latitudinal transect from the Arctic to the tropics. Near-surface low-latitude peat has lower carbohydrate and greater aromatic content than near-surface high-latitude peat, creating a reduced oxidation state and resulting recalcitrance. This recalcitrance allows peat to persist in the (sub)tropics despite warm temperatures. Because we observed similar declines in carbohydrate content with depth in high-latitude peat, our data explain recent field-scale deep peat warming experiments in which catotelm (deeper) peat remained stable despite temperature increases up to 9 degrees C. We suggest that high-latitude deep peat reservoirs may be stabilized in the face of climate change by their ultimately lower carbohydrate and higher aromatic composition, similar to tropical peats.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1125 
KW  - dissolved organic matter
KW  - greenhouse gas fluxes
KW  - permafrost thaw
KW  - Northern Minnesota
KW  - FTIR spectroscopy
KW  - lignin content
KW  - brown rot
KW  - decomposition
KW  - chemistry
KW  - dynamics
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-459658
SN  - 1866-8372
IS  - 1125
ER  - 
TY  - JOUR
A1  - Cohen, Andrew
A1  - Campisano, C.
A1  - Arrowsmith, J. Ramón
A1  - Asrat, Asfawossen
A1  - Behrensmeyer, A. K.
A1  - Deino, A.
A1  - Feibel, C.
A1  - Hill, A.
A1  - Johnson, R.
A1  - Kingston, J.
A1  - Lamb, Henry F.
A1  - Lowenstein, T.
A1  - Noren, A.
A1  - Olago, D.
A1  - Owen, R. B.
A1  - Potts, R.
A1  - Reed, Kate
A1  - Renaut, R.
A1  - Schäbitz, Frank
A1  - Tiercelin, J. -J.
A1  - Trauth, Martin H.
A1  - Wynn, J.
A1  - Ivory, S.
A1  - Brady, K.
A1  - Rodysill, J.
A1  - Githiri, J.
A1  - Russell, J.
A1  - Förster, Verena
A1  - Dommain, René
A1  - Rucina, S.
A1  - Deocampo, D.
A1  - Russell, J.
A1  - Billingsley, A.
A1  - Beck, C.
A1  - Dorenbeck, G.
A1  - Dullo, L.
A1  - Feary, D.
A1  - Garello, D.
A1  - Gromig, R.
A1  - Johnson, T.
A1  - Junginger, A.
A1  - Karanja, M.
A1  - Kimburi, E.
A1  - Mbuthia, A.
A1  - McCartney, T.
A1  - McNulty, E.
A1  - Muiruri, V.
A1  - Nambiro, E.
A1  - Negash, E. W.
A1  - Njagi, D.
A1  - Wilson, J. N.
A1  - Rabideaux, N.
A1  - Raub, T.
A1  - Sier, M. J.
A1  - Smith, P.
A1  - Urban, J.
A1  - Warren, M.
A1  - Yadeta, M.
A1  - Yost, C.
A1  - Zinaye, B.
T1  - The Hominin Sites and Paleolakes Drilling Project: inferring the environmental context of human evolution from eastern African rift lake deposits
JF  - Scientific Drilling
N2  - The role that climate and environmental history may have played in influencing human evolution has been the focus of considerable interest and controversy among paleoanthropologists for decades. Prior attempts to understand the environmental history side of this equation have centered around the study of outcrop sediments and fossils adjacent to where fossil hominins (ancestors or close relatives of modern humans) are found, or from the study of deep sea drill cores. However, outcrop sediments are often highly weathered and thus are unsuitable for some types of paleoclimatic records, and deep sea core records come from long distances away from the actual fossil and stone tool remains. The Hominin Sites and Paleolakes Drilling Project (HSPDP) was developed to address these issues. The project has focused its efforts on the eastern African Rift Valley, where much of the evidence for early hominins has been recovered. We have collected about 2 km of sediment drill core from six basins in Kenya and Ethiopia, in lake deposits immediately adjacent to important fossil hominin and archaeological sites. Collectively these cores cover in time many of the key transitions and critical intervals in human evolutionary history over the last 4 Ma, such as the earliest stone tools, the origin of our own genus Homo, and the earliest anatomically modern Homo sapiens. Here we document the initial field, physical property, and core description results of the 2012-2014 HSPDP coring campaign.
Y1  - 2016
U6  - https://doi.org/10.5194/sd-21-1-2016
SN  - 1816-8957
SN  - 1816-3459
VL  - 21
SP  - 1
EP  - 16
PB  - Copernicus
CY  - Göttingen
ER  - 
TY  - GEN
A1  - Cohen, Abby
A1  - Campisano, Christopher
A1  - Arrowsmith, J. Ramon
A1  - Asrat, Asfawossen
A1  - Behrensmeyer, A. K.
A1  - Deino, A.
A1  - Feibel, C.
A1  - Hill, A.
A1  - Johnson, R.
A1  - Kingston, J.
A1  - Lamb, Henry F.
A1  - Lowenstein, T.
A1  - Noren, A.
A1  - Olago, D.
A1  - Owen, Richard Bernhart
A1  - Potts, R.
A1  - Reed, Kate
A1  - Renaut, R.
A1  - Schäbitz, F.
A1  - Tiercelin, J.-J.
A1  - Trauth, Martin  H.
A1  - Wynn, J.
A1  - Ivory, S.
A1  - Brady, K.
A1  - O’Grady, R.
A1  - Rodysill, J.
A1  - Githiri, J.
A1  - Russell, Joellen
A1  - Foerster, Verena
A1  - Dommain, René
A1  - Rucina, J. S.
A1  - Deocampo, D.
A1  - Russell, J.
A1  - Billingsley, A.
A1  - Beck, C.
A1  - Dorenbeck, G.
A1  - Dullo, L.
A1  - Feary, D.
A1  - Garello, D.
A1  - Gromig, R.
A1  - Johnson, T.
A1  - Junginger, Annett
A1  - Karanja, M.
A1  - Kimburi, E.
A1  - Mbuthia, A.
A1  - McCartney, Tannis
A1  - McNulty, E.
A1  - Muiruri, V.
A1  - Nambiro, E.
A1  - Negash, E. W.
A1  - Njagi, D.
A1  - Wilson, J. N.
A1  - Rabideaux, N.
A1  - Raub, Timothy
A1  - Sier, Mark Jan
A1  - Smith, P.
A1  - Urban, J.
A1  - Warren, M.
A1  - Yadeta, M.
A1  - Yost, Chad
A1  - Zinaye, B.
T1  - The Hominin Sites and Paleolakes Drilling Project
BT  - inferring the environmental context of human evolution from eastern African rift lake deposits
T2  - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe
N2  - The role that climate and environmental history may have played in influencing human evolution has been the focus of considerable interest and controversy among paleoanthropologists for decades. Prior attempts to understand the environmental history side of this equation have centered around the study of outcrop sediments and fossils adjacent to where fossil hominins (ancestors or close relatives of modern humans) are found, or from the study of deep sea drill cores. However, outcrop sediments are often highly weathered and thus are unsuitable for some types of paleoclimatic records, and deep sea core records come from long distances away from the actual fossil and stone tool remains. The Hominin Sites and Paleolakes Drilling Project (HSPDP) was developed to address these issues. The project has focused its efforts on the eastern African Rift Valley, where much of the evidence for early hominins has been recovered. We have collected about 2 km of sediment drill core from six basins in Kenya and Ethiopia, in lake deposits immediately adjacent to important fossil hominin and archaeological sites. Collectively these cores cover in time many of the key transitions and critical intervals in human evolutionary history over the last 4 Ma, such as the earliest stone tools, the origin of our own genus Homo, and the earliest anatomically modern Homo sapiens. Here we document the initial field, physical property, and core description results of the 2012-2014 HSPDP coring campaign.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 611 
KW  - Turkana-Basin
KW  - Adar formation
KW  - climate-change
KW  - olorgesailie formation
KW  - Southern Ethiopia
KW  - global climate
KW  - Kenya Rift
KW  - Pleistocene
KW  - variability
KW  - patterns
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-412498
IS  - 611
ER  - 
TY  - GEN
A1  - Dommain, René
A1  - Andama, Morgan
A1  - McDonough, Molly M.
A1  - Prado, Natalia A.
A1  - Goldhammer, Tobias
A1  - Potts, Richard
A1  - Maldonado, Jesús E.
A1  - Nkurunungi, John Bosco
A1  - Campana, Michael G.
T1  - The Challenges of Reconstructing Tropical Biodiversity With Sedimentary Ancient DNA
BT  - A 2200-Year-Long Metagenomic Record From Bwindi Impenetrable Forest, Uganda
T2  - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe
N2  - Sedimentary ancient DNA has been proposed as a key methodology for reconstructing biodiversity over time. Yet, despite the concentration of Earth’s biodiversity in the tropics, this method has rarely been applied in this region. Moreover, the taphonomy of sedimentary DNA, especially in tropical environments, is poorly understood. This study elucidates challenges and opportunities of sedimentary ancient DNA approaches for reconstructing tropical biodiversity. We present shotgun-sequenced metagenomic profiles and DNA degradation patterns from multiple sediment cores from Mubwindi Swamp, located in Bwindi Impenetrable Forest (Uganda), one of the most diverse forests in Africa. We describe the taxonomic composition of the sediments covering the past 2200 years and compare the sedimentary DNA data with a comprehensive set of environmental and sedimentological parameters to unravel the conditions of DNA degradation. Consistent with the preservation of authentic ancient DNA in tropical swamp sediments, DNA concentration and mean fragment length declined exponentially with age and depth, while terminal deamination increased with age. DNA preservation patterns cannot be explained by any environmental parameter alone, but age seems to be the primary driver of DNA degradation in the swamp. Besides degradation, the presence of living microbial communities in the sediment also affects DNA quantity. Critically, 92.3% of our metagenomic data of a total 81.8 million unique, merged reads cannot be taxonomically identified due to the absence of genomic references in public databases. Of the remaining 7.7%, most of the data (93.0%) derive from Bacteria and Archaea, whereas only 0–5.8% are from Metazoa and 0–6.9% from Viridiplantae, in part due to unbalanced taxa representation in the reference data. The plant DNA record at ordinal level agrees well with local pollen data but resolves less diversity. Our animal DNA record reveals the presence of 41 native taxa (16 orders) including Afrotheria, Carnivora, and Ruminantia at Bwindi during the past 2200 years. Overall, we observe no decline in taxonomic richness with increasing age suggesting that several-thousand-year-old information on past biodiversity can be retrieved from tropical sediments. However, comprehensive genomic surveys of tropical biota need prioritization for sedimentary DNA to be a viable methodology for future tropical biodiversity studies.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 970 
KW  - sedimentary ancient DNA
KW  - tropical biodiversity
KW  - DNA preservation
KW  - sediment
KW  - tropical swamp
KW  - shotgun sequencing
KW  - metagenomic analysis
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-474305
SN  - 1866-8372
IS  - 970
ER  - 
TY  - JOUR
A1  - Dommain, René
A1  - Andama, Morgan
A1  - McDonough, Molly M.
A1  - Prado, Natalia A.
A1  - Goldhammer, Tobias
A1  - Potts, Richard
A1  - Maldonado, Jesús E.
A1  - Nkurunungi, John Bosco
A1  - Campana, Michael G.
T1  - The Challenges of Reconstructing Tropical Biodiversity With Sedimentary Ancient DNA
BT  - A 2200-Year-Long Metagenomic Record From Bwindi Impenetrable Forest, Uganda
JF  - Frontiers in Ecology and Evolution
N2  - Sedimentary ancient DNA has been proposed as a key methodology for reconstructing biodiversity over time. Yet, despite the concentration of Earth’s biodiversity in the tropics, this method has rarely been applied in this region. Moreover, the taphonomy of sedimentary DNA, especially in tropical environments, is poorly understood. This study elucidates challenges and opportunities of sedimentary ancient DNA approaches for reconstructing tropical biodiversity. We present shotgun-sequenced metagenomic profiles and DNA degradation patterns from multiple sediment cores from Mubwindi Swamp, located in Bwindi Impenetrable Forest (Uganda), one of the most diverse forests in Africa. We describe the taxonomic composition of the sediments covering the past 2200 years and compare the sedimentary DNA data with a comprehensive set of environmental and sedimentological parameters to unravel the conditions of DNA degradation. Consistent with the preservation of authentic ancient DNA in tropical swamp sediments, DNA concentration and mean fragment length declined exponentially with age and depth, while terminal deamination increased with age. DNA preservation patterns cannot be explained by any environmental parameter alone, but age seems to be the primary driver of DNA degradation in the swamp. Besides degradation, the presence of living microbial communities in the sediment also affects DNA quantity. Critically, 92.3% of our metagenomic data of a total 81.8 million unique, merged reads cannot be taxonomically identified due to the absence of genomic references in public databases. Of the remaining 7.7%, most of the data (93.0%) derive from Bacteria and Archaea, whereas only 0–5.8% are from Metazoa and 0–6.9% from Viridiplantae, in part due to unbalanced taxa representation in the reference data. The plant DNA record at ordinal level agrees well with local pollen data but resolves less diversity. Our animal DNA record reveals the presence of 41 native taxa (16 orders) including Afrotheria, Carnivora, and Ruminantia at Bwindi during the past 2200 years. Overall, we observe no decline in taxonomic richness with increasing age suggesting that several-thousand-year-old information on past biodiversity can be retrieved from tropical sediments. However, comprehensive genomic surveys of tropical biota need prioritization for sedimentary DNA to be a viable methodology for future tropical biodiversity studies.
KW  - sedimentary ancient DNA
KW  - tropical biodiversity
KW  - DNA preservation
KW  - sediment
KW  - tropical swamp
KW  - shotgun sequencing
KW  - metagenomic analysis
Y1  - 2019
U6  - https://doi.org/10.3389/fevo.2020.00218
SN  - 2296-701X
VL  - 8
PB  - Frontiers Media
CY  - Lausanne
ER  - 
TY  - JOUR
A1  - Cobb, Alexander R.
A1  - Hoyt, Alison M.
A1  - Gandois, Laure
A1  - Eri, Jangarun
A1  - Dommain, René
A1  - Abu Salim, Kamariah
A1  - Kai, Fuu Ming
A1  - Harvey, Charles F.
T1  - How temporal patterns in rainfall determine the geomorphology and carbon fluxes of tropical peatlands
JF  - Proceedings of the National Academy of Sciences of the United States of America
N2  - Tropical peatlands now emit hundreds of megatons of carbon dioxide per year because of human disruption of the feedbacks that link peat accumulation and groundwater hydrology. However, no quantitative theory has existed for how patterns of carbon storage and release accompanying growth and subsidence of tropical peatlands are affected by climate and disturbance. Using comprehensive data from a pristine peatland in Brunei Darussalam, we show how rainfall and groundwater flow determine a shape parameter (the Laplacian of the peat surface elevation) that specifies, under a given rainfall regime, the ultimate, stable morphology, and hence carbon storage, of a tropical peatland within a network of rivers or canals. We find that peatlands reach their ultimate shape first at the edges of peat domes where they are bounded by rivers, so that the rate of carbon uptake accompanying their growth is proportional to the area of the still-growing dome interior. We use this model to study how tropical peatland carbon storage and fluxes are controlled by changes in climate, sea level, and drainage networks. We find that fluctuations in net precipitation on timescales from hours to years can reduce long-term peat accumulation. Our mathematical and numerical models can be used to predict long-term effects of changes in temporal rainfall patterns and drainage networks on tropical peatland geomorphology and carbon storage.
KW  - tropical peatlands
KW  - peatland geomorphology
KW  - peatland hydrology
KW  - peatland carbon storage
KW  - climate-carbon cycle feedbacks
Y1  - 2017
U6  - https://doi.org/10.1073/pnas.1701090114
SN  - 0027-8424
VL  - 114
SP  - E5187
EP  - E5196
PB  - National Acad. of Sciences
CY  - Washington
ER  - 
TY  - JOUR
A1  - Deino, A. L.
A1  - Dommain, René
A1  - Keller, C. B.
A1  - Potts, R.
A1  - Behrensmeyer, A. K.
A1  - Beverly, E. J.
A1  - King, J.
A1  - Heil, C. W.
A1  - Stockhecke, M.
A1  - Brown, E. T.
A1  - Moerman, J.
A1  - deMenocal, P.
A1  - Deocampo, D.
A1  - Garcin, Yannick
A1  - Levin, N. E.
A1  - Lupien, R.
A1  - Owen, R. B.
A1  - Rabideaux, N.
A1  - Russell, J. M.
A1  - Scott, J.
A1  - Riedl, S.
A1  - Brady, K.
A1  - Bright, J.
A1  - Clark, J. B.
A1  - Cohen, A.
A1  - Faith, J. T.
A1  - Noren, A.
A1  - Muiruri, V.
A1  - Renaut, R.
A1  - Rucina, S.
A1  - Uno, K.
T1  - Chronostratigraphic model of a high-resolution drill core record of the past million years from the Koora Basin, south Kenya Rift: Overcoming the difficulties of variable sedimentation rate and hiatuses
JF  - Quaternary science reviews : the international multidisciplinary research and review journal
N2  - The Olorgesailie Drilling Project and the related Hominin Sites and Paleolakes Drilling Project in East Africa were initiated to test hypotheses and models linking environmental change to hominin evolution by drilling lake basin sediments adjacent to important archeological and paleoanthropological sites. Drill core OL012-1A recovered 139 m of sedimentary and volcaniclastic strata from the Koora paleolake basin, southern Kenya Rift, providing the opportunity to compare paleoenvironmental influences over the past million years with the parallel record exposed at the nearby Olorgesailie archeological site. To refine our ability to link core-to-outcrop paleoenvironmental records, we institute here a methodological framework for deriving a robust age model for the complex lithostratigraphy of OL012-1A. Firstly, chronostratigraphic control points for the core were established based on 4 Ar/39Ar ages from intercalated tephra deposits and a basal trachyte flow, as well as the stratigraphic position of the Brunhes-Matuyama geomagnetic reversal. This dataset was combined with the position and duration of paleosols, and analyzed using a new Bayesian algorithm for high-resolution age-depth modeling of hiatus-bearing stratigraphic sections. This model addresses three important aspects relevant to highly dynamic, nonlinear depositional environments: 1) correcting for variable rates of deposition, 2) accommodating hiatuses, and 3) quantifying realistic age uncertainty with centimetric resolution. Our method is applicable to typical depositional systems in extensional rifts as well as to drill cores from other dynamic terrestrial or aquatic environments. We use the core age model and lithostratigraphy to examine the inter connectivity of the Koora Basin to adjacent areas and sources of volcanism. (C) 2019 Elsevier Ltd. All rights reserved.
KW  - Pleistocene
KW  - Paleolimnology
KW  - East Africa
KW  - Sedimentology
KW  - Radiogenic isotopes
KW  - Bayesian modeling
KW  - paleosol
KW  - Tephrostratigraphy
KW  - Magnetostratigraphy
KW  - Kenya Rift
Y1  - 2019
U6  - https://doi.org/10.1016/j.quascirev.2019.05.009
SN  - 0277-3791
VL  - 215
SP  - 213
EP  - 231
PB  - Elsevier
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Dommain, René
A1  - Frolking, Steve
A1  - Jeltsch-Thömmes, Aurich
A1  - Joos, Fortunat Ulrich
A1  - Couwenberg, John
A1  - Glaser, Paul H.
T1  - A radiative forcing analysis of tropical peatlands before and after their conversion to agricultural plantations
JF  - Global change biology
N2  - The tropical peat swamp forests of South-East Asia are being rapidly converted to agricultural plantations of oil palm and Acacia creating a significant global “hot-spot” for CO2 emissions. However, the effect of this major perturbation has yet to be quantified in terms of global warming potential (GWP) and the Earth's radiative budget. We used a GWP analysis and an impulse-response model of radiative forcing to quantify the climate forcing of this shift from a long-term carbon sink to a net source of greenhouse gases (CO2 and CH4). In the GWP analysis, five tropical peatlands were sinks in terms of their CO2 equivalent fluxes while they remained undisturbed. However, their drainage and conversion to oil palm and Acacia plantations produced a dramatic shift to very strong net CO2-equivalent sources. The induced losses of peat carbon are ~20× greater than the natural CO2 sequestration rates. In contrast, a radiative forcing model indicates that the magnitude of this shift from a net cooling to warming effect is ultimately related to the size of an individual peatland's carbon pool. The continuous accumulation of carbon in pristine tropical peatlands produced a progressively negative radiative forcing (i.e., cooling) that ranged from −2.1 to −6.7 nW/m2 per hectare peatland by 2010 CE, referenced to zero at the time of peat initiation. Peatland conversion to plantations leads to an immediate shift from negative to positive trend in radiative forcing (i.e., warming). If drainage persists, peak warming ranges from +3.3 to +8.7 nW/m2 per hectare of drained peatland. More importantly, this net warming impact on the Earth's radiation budget will persist for centuries to millennia after all the peat has been oxidized to CO2. This previously unreported and undesirable impact on the Earth's radiative balance provides a scientific rationale for conserving tropical peatlands in their pristine state.
KW  - Acacia plantation
KW  - CO2 emissions
KW  - drainage-based land use
KW  - global warming potential
KW  - oil palm plantation
KW  - radiative forcing
KW  - tropical peatland
Y1  - 2018
U6  - https://doi.org/10.1111/gcb.14400
SN  - 1354-1013
SN  - 1365-2486
VL  - 24
IS  - 11
SP  - 5518
EP  - 5533
PB  - Wiley
CY  - Hoboken
ER  -