Journal articles: 'Proxy paleoenvironmental'

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Moldovan, O. T., S. Constantin, C. Panaiotu, R. D. Roban, P. Frenzel, and L. Miko. "Fossil invertebrates records in cave sediments and paleoenvironmental assessments – a study of four cave sites from Romanian Carpathians." Biogeosciences 13, no. 2 (January 25, 2016): 483–97. http://dx.doi.org/10.5194/bg-13-483-2016.

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Abstract. Fossil invertebrates from cave sediments have been recently described as a potential new proxy for paleoenvironment and used in cross-correlations with alternate proxy records from cave deposits. Here we present the results of a fossil invertebrates study in four caves from two climatically different regions of the Romanian Carpathians, to complement paleoenvironmental data previously reported. Oribatid mites and ostracods are the most common invertebrates in the studied cave sediments. Some of the identified taxa are new to science, and most of them are indicative for either warm and/or cold stages or dry and/or wetter oscillations. In two caves the fossil invertebrates records indicate rapid climate oscillations during times known for a relatively stable climate. By corroborating the fossil invertebrates' record with the information given by magnetic properties and sediment structures, complementary data on past vegetation, temperatures and hydraulic regimes could be gathered. This paper analyzes the potential of fossil invertebrate records as a paleoenvironmental proxy, potential problems and pitfalls.

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Moldovan, O. T., S. Constantin, C. Panaiotu, R. D. Roban, P. Frenzel, and L. Miko. "Fossil invertebrates records in cave sediments and paleoenvironmental assessments: a study of four cave sites from Romanian Carpathians." Biogeosciences Discussions 12, no. 11 (June 15, 2015): 8849–81. http://dx.doi.org/10.5194/bgd-12-8849-2015.

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Abstract. Fossil invertebrates from cave sediments have been recently described as a potential new proxy for paleoenvironment and used in cross-correlations with alternate proxy records from cave deposits. Here we present the results of a fossil invertebrates study in four caves from two climatically different regions of the Romanian Carpathians, to complement paleoenvironmental data previously reported. Oribatid mites and ostracods are the most common invertebrates in the studied cave sediments. Some of the identified taxa are new for science, and most of them are indicative for either warm/cold stages or dry/wetter oscillations. In two caves the fossil invertebrates records indicate rapid climate oscillations during times known for a relatively stable climate. By corroborating the fossil invertebrates' record with the information given by magnetic properties and sediment structures, complementary data on past vegetation, temperatures, and hydraulic regimes could be gathered. This paper analyses the potential of fossil invertebrate records as a paleoenvironmental proxy, potential problems and pitfalls.

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Liu, Bing, Robert K. Booth, Jaime Escobar, Zhiqiang Wei, Broxton W. Bird, Andres Pardo, Jason H. Curtis, and Jun Ouyang. "Ecology and paleoenvironmental application of testate amoebae in peatlands of the high-elevation Colombian páramo." Quaternary Research 92, no. 1 (February 18, 2019): 14–32. http://dx.doi.org/10.1017/qua.2018.143.

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AbstractWe investigated the ecology and paleoecology of testate amoebae in peatlands of the Colombian páramo to assess the use of testate amoebae as paleoenvironmental indicators. Objectives were to (1) identify environmental controls on testate amoebae, (2) develop transfer functions for paleoenvironmental inference, and (3) examine testate amoebae in a Holocene peat core and compare our findings with other proxy records. Results from 96 modern samples indicate that testate amoebae are sensitive to pH and surface moisture, and cross-validation of transfer functions indicates potential for paleoenvironmental applications. Testate amoebae from the Triunfo Peatland in the Central Cordillera provided a proxy record of pH and water-table depth for the late Holocene, and inferred changes were correlated with peat C/N measurements during most of the record. Comparison with a lake-level reconstruction suggests that at least the major testate amoeba–inferred changes were driven by climate. Our work indicates that testate amoebae are useful paleoenvironmental indicators in high-elevation tropical peatlands.

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Börner, Nicole, Bart De Baere, Qichao Yang, Klaus Peter Jochum, Peter Frenzel, Meinrat O. Andreae, and Antje Schwalb. "Ostracod shell chemistry as proxy for paleoenvironmental change." Quaternary International 313-314 (November 2013): 17–37. http://dx.doi.org/10.1016/j.quaint.2013.09.041.

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DOCIO, L., M. PAROLIN, and U. PINHEIRO. "A contribution to adequate use of freshwater sponges as a proxy in paleoenvironmental studies." Zootaxa 4915, no. 4 (January 25, 2021): 506–28. http://dx.doi.org/10.11646/zootaxa.4915.4.3.

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This paper provides a comprehensive review of the environments where freshwater sponges occur and evaluates the use of sponge spicules as a proxy in paleoenvironmental studies in the Neotropical region. The paper aims to: I) review the information about the ecology of inland sponges to facilitate the use of spicules as a paleoenvironmental tool; and II) identify possible incongruities in the use of this information in paleoenvironmental reconstructions that have been conducted in Neotropical regions. The study compiled data on 77 sponge species, specialist or generalist that occur under certain environmental conditions, such as: substrate type for growth, hydrodynamic types, as well as salinity and acidity concentrations. In addition, it provides a comparison of the paleoenvironmental conditions applied to reconstruction studies that have been carried out within this biogeographic region, highlighting incongruities regarding the current ecology of the sponges.

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Bowen, Gabriel J., Brenden Fischer-Femal, Gert-Jan Reichart, Appy Sluijs, and Caroline H. Lear. "Joint inversion of proxy system models to reconstruct paleoenvironmental time series from heterogeneous data." Climate of the Past 16, no. 1 (January 9, 2020): 65–78. http://dx.doi.org/10.5194/cp-16-65-2020.

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Abstract. Paleoclimatic and paleoenvironmental reconstructions are fundamentally uncertain because no proxy is a direct record of a single environmental variable of interest; all proxies are indirect and sensitive to multiple forcing factors. One productive approach to reducing proxy uncertainty is the integration of information from multiple proxy systems with complementary, overlapping sensitivity. Mostly, such analyses are conducted in an ad hoc fashion, either through qualitative comparison to assess the similarity of single-proxy reconstructions or through step-wise quantitative interpretations where one proxy is used to constrain a variable relevant to the interpretation of a second proxy. Here we propose the integration of multiple proxies via the joint inversion of proxy system and paleoenvironmental time series models in a Bayesian hierarchical framework. The “Joint Proxy Inversion” (JPI) method provides a statistically robust approach to producing self-consistent interpretations of multi-proxy datasets, allowing full and simultaneous assessment of all proxy and model uncertainties to obtain quantitative estimates of past environmental conditions. Other benefits of the method include the ability to use independent information on climate and environmental systems to inform the interpretation of proxy data, to fully leverage information from unevenly and differently sampled proxy records, and to obtain refined estimates of proxy model parameters that are conditioned on paleo-archive data. Application of JPI to the marine Mg∕Ca and δ18O proxy systems at two distinct timescales demonstrates many of the key properties, benefits, and sensitivities of the method, and it produces new, statistically grounded reconstructions of Neogene ocean temperature and chemistry from previously published data. We suggest that JPI is a universally applicable method that can be implemented using proxy models of wide-ranging complexity to generate more robust, quantitative understanding of past climatic and environmental change.

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Mitchell, Edward A. D., Richard J. Payne, Willem O. van der Knaap, Łukasz Lamentowicz, Maciej Gąbka, and Mariusz Lamentowicz. "The performance of single- and multi-proxy transfer functions (testate amoebae, bryophytes, vascular plants) for reconstructing mire surface wetness and pH." Quaternary Research 79, no. 1 (January 2013): 6–13. http://dx.doi.org/10.1016/j.yqres.2012.08.004.

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AbstractPeatlands are widely exploited archives of paleoenvironmental change. We developed and compared multiple transfer functions to infer peatland depth to the water table (DWT) and pH based on testate amoeba (percentages, or presence/absence), bryophyte presence/absence, and vascular plant presence/absence data from sub-alpine peatlands in the SE Swiss Alps in order to 1) compare the performance of single-proxy vs. multi-proxy models and 2) assess the performance of presence/absence models. Bootstrapping cross-validation showing the best performing single-proxy transfer functions for both DWT and pH were those based on bryophytes. The best performing transfer functions overall for DWT were those based on combined testate amoebae percentages, bryophytes and vascular plants; and for pH, those based on testate amoebae and bryophytes. The comparison of DWT and pH inferred from testate amoeba percentages and presence/absence data showed similar general patterns but differences in the magnitude and timing of some shifts. These results show new directions for paleoenvironmental research, 1) suggesting that it is possible to build good-performing transfer functions using presence/absence data, although with some loss of accuracy, and 2) supporting the idea that multi-proxy inference models may improve paleoecological reconstruction. The performance of multi-proxy and single-proxy transfer functions should be further compared in paleoecological data.

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Cruz, J. Alberto, Julián A. Velasco, Joaquín Arroyo-Cabrales, and Eileen Johnson. "Paleoclimatic Reconstruction Based on the Late Pleistocene San Josecito Cave Stratum 720 Fauna Using Fossil Mammals, Reptiles, and Birds." Diversity 15, no. 7 (July 24, 2023): 881. http://dx.doi.org/10.3390/d15070881.

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Advances in technology have equipped paleobiologists with new analytical tools to assess the fossil record. The functional traits of vertebrates have been used to infer paleoenvironmental conditions. In Quaternary deposits, birds are the second-most-studied group after mammals. They are considered a poor paleoambiental proxy because their high vagility and phenotypic plasticity allow them to respond more effectively to climate change. Investigating multiple groups is important, but it is not often attempted. Biogeographical and climatic niche information concerning small mammals, reptiles, and birds have been used to infer the paleoclimatic conditions present during the Late Pleistocene at San Josecito Cave (~28,000 14C years BP), Mexico. Warmer and dryer conditions are inferred with respect to the present. The use of all of the groups of small vertebrates is recommended because they represent an assemblage of species that have gone through a series of environmental filters in the past. Individually, different vertebrate groups provide different paleoclimatic information. Birds are a good proxy for inferring paleoprecipitation but not paleotemperature. Together, reptiles and small mammals are a good proxy for inferring paleoprecipitation and paleotemperature, but reptiles alone are a bad proxy, and mammals alone are a good proxy for inferring paleotemperature and precipitation. The current paleoclimatic results coupled with those of a previous vegetation structure analysis indicate the presence of non-analog paleoenvironmental conditions during the Late Pleistocene in the San Josecito Cave area. This situation would explain the presence of a disharmonious fauna and the extinction of several taxa when these conditions later disappeared and do not reappear again.

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SOWA, Kohki, Tsuyoshi WATANABE, Michiyo SHIMAMURA, Tatsuhiko SAKAMOTO, and Seiya NAGAO. "Coral skeletal luminescence- its causes and availability as a paleoenvironmental proxy." Journal of the Japanese Coral Reef Society 12 (2010): 1–15. http://dx.doi.org/10.3755/jcrs.12.1.

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Beaudoin, Alwynne B. "On the Identification and Characterization of Drought and Aridity in Postglacial Paleoenvironmental Records from the Northern Great Plains." Géographie physique et Quaternaire 56, no. 2-3 (October 7, 2004): 229–46. http://dx.doi.org/10.7202/009108ar.

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Abstract The Northern Great Plains region is especially sensitive to drought and is likely to be even more drought-prone under projected global warming. Drought has been invoked as an explanatory factor for changes seen in postglacial paleoenvironmental records. These proxy records may extend drought history derived from instrumental data. Moreover, in the last decade, some paleoenvironmental studies have been expressly undertaken for the examination of long-term drought history. Nevertheless, few such studies explicitly define drought. This makes it difficult to compare results or to understand what the results mean in terms of the operational drought definitions that are used in resource management. Operational drought is defined as usually short-term; longer sustained dry intervals reflect a shift to aridity. Therefore, high resolution paleoenvironmental proxies (annual or subdecadal) are best for the investigation of drought history. Such proxies include tree rings and some lake records. However, most lake-based records are sampled at lower resolution (decadal or subcentury) and are therefore providing aridity signals.

11

Juggins, Steve. "A PEP III Multi-Proxy Database for Managing and Analyzing Paleoenvironmental Data." PAGES news 6, no. 2 (December 1998): 6. http://dx.doi.org/10.22498/pages.6.2.6.

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Brown, Sabrina R., Rosine Cartier, Christopher M. Schiller, Petra Zahajská, Sherilyn C. Fritz, Lisa A. Morgan, Cathy Whitlock, et al. "Multi-proxy record of Holocene paleoenvironmental conditions from Yellowstone Lake, Wyoming, USA." Quaternary Science Reviews 274 (December 2021): 107275. http://dx.doi.org/10.1016/j.quascirev.2021.107275.

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Kuznetsova, Alsu M., and Olga S. Khokhlova. "Submicromorphology of pedogenic carbonate accumulations as a proxy of modern and paleoenvironmental conditions." Boletín de la Sociedad Geológica Mexicana 64, no. 2 (2012): 199–205. http://dx.doi.org/10.18268/bsgm2012v64n2a5.

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Xiao, Liang, BaiNian Sun, XiangChuan Li, WenXiu Ren, and Hui Jia. "Anatomical variations of living and fossil Liquidambar leaves: A proxy for paleoenvironmental reconstruction." Science China Earth Sciences 54, no. 4 (April 2011): 493–508. http://dx.doi.org/10.1007/s11430-010-4135-4.

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Layzell, Anthony L., Rolfe D. Mandel, Greg A. Ludvigson, Tammy M. Rittenour, and Jon J. Smith. "Forces driving late Pleistocene (ca. 77–12 ka) landscape evolution in the Cimarron River valley, southwestern Kansas." Quaternary Research 84, no. 1 (July 2015): 106–17. http://dx.doi.org/10.1016/j.yqres.2015.05.003.

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This study presents stratigraphic, geomorphic, and paleoenvironmental (δ13C) data that provide insight into the late Pleistocene landscape evolution of the Cimarron River valley in the High Plains of southwestern Kansas. Two distinct valley fills (T-1 and T-2) were investigated. Three soils occur in the T-2 fill and five in the T-1 fill, all indicating periods of landscape stability or slow sedimentation. Of particular interest are two cumulic soils dating to ca. 48–28 and 13–12.5 ka. δ13C values are consistent with regional paleoenvironmental proxy data that indicate the prevalence of warm, dry conditions at these times. The Cimarron River is interpreted to have responded to these climatic changes and to local base level control. Specifically, aggradation occurred during cool, wet periods and slow sedimentation with cumulic soil formation occurred under warmer, drier climates. Significant valley incision (~ 25 m) by ca. 28 ka likely resulted from a lowering of local base level caused by deep-seated dissolution of Permian evaporite deposits.

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Kouli, Katerina, Maria V. Triantaphyllou, Olga Koukousioura, Margarita D. Dimiza, Constantine Parinos, Ioannis P. Panagiotopoulos, Theodora Tsourou, et al. "Late Glacial Marine Transgression and Ecosystem Response in the Landlocked Elefsis Bay (Northern Saronikos Gulf, Greece)." Water 13, no. 11 (May 27, 2021): 1505. http://dx.doi.org/10.3390/w13111505.

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Coastal landscapes are sensitive to changes due to the interplay between surface and submarine geological processes, climate variability, and relative sea level fluctuations. The sedimentary archives of such marginal areas record in detail the complex evolution of the paleoenvironment and the diachronic biota response. The Elefsis Bay is nowadays a landlocked shallow marine basin with restricted communication to the open Saronikos Gulf. A multi-proxy investigation of a high-resolution sediment core recovered from the deepest part of the basin offered a unique opportunity to record the paleoenvironmental and aquatic ecosystem response to climate and glacioeustatic sea level changes since the Late Glacial marine transgression. The retrieved sedimentary deposits, subjected to thorough palynological (pollen, non-pollen palynomorphs, dinoflagellates), micropaleontological (benthic foraminifera, calcareous nannoplankton, ostracods), and mollusc analyses, indicates isolation of the Elefsis Bay from the Saronikos Gulf and the occurrence of a shallow freshwater paleolake since at least 13,500 cal BP, while after 11,350 cal BP the transition towards lagoon conditions is evidenced. The marine transgression in the Elefsis Bay is dated at 7500 cal BP, marking the establishment of the modern marine realm.

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Garnier, J. M., J. Garnier, P. Debnath, L. F. Prado, E. Yokoyama, R. K. Das, P. E. Mathé, and M. S. Islam. "Late Holocene paleoenvironmental records in Eastern Bangladesh from lake sediments: A multi-proxy approach." Quaternary International 558 (August 2020): 39–46. http://dx.doi.org/10.1016/j.quaint.2020.06.049.

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Argiriadis, Elena, Matteo Martino, Michela Segnana, Luisa Poto, Marco Vecchiato, Dario Battistel, Andrea Gambaro, and Carlo Barbante. "Multi-proxy biomarker determination in peat: Optimized extraction and cleanup method for paleoenvironmental application." Microchemical Journal 156 (July 2020): 104821. http://dx.doi.org/10.1016/j.microc.2020.104821.

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Chen, Jingan, Jian Li, Shihong Tian, Ivan Kalugin, Andrey Darin, and Sheng Xu. "Silicon isotope composition of diatoms as a paleoenvironmental proxy in Lake Huguangyan, South China." Journal of Asian Earth Sciences 45 (February 2012): 268–74. http://dx.doi.org/10.1016/j.jseaes.2011.11.010.

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Torricella, Fiorenza, Olivia Truax, Danilo Morelli, Francesca Battaglia, Nicola Corradi, Xavier Crosta, Laura De Santis, et al. "Multi-proxy paleoenvironmental reconstruction of Robertson Bay, East Antarctica, since the last glacial period." Quaternary Science Reviews 332 (May 2024): 108629. http://dx.doi.org/10.1016/j.quascirev.2024.108629.

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Thompson, Natalie S., and Beth E. Caissie. "Evaluating the paleoenvironmental significance of sediment grain size in Bering Sea sediments during Marine Isotope Stage 11." Stratigraphy 19, no. 2 (June 2022): 119–39. http://dx.doi.org/10.29041/strat.19.2.03.

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Grain size is an important textural property of sediments and is widely used in paleoenvironmental studies as a means to infer changes in the sedimentary environment. However, grain size parameters are not always easy to interpret without a full understanding of the factors that influence grain size. Here, we measure grain size in sediment cores from the Bering slope and the Umnak Plateau, and review the effectiveness of different grain size parameters as proxies for sediment transport, current strength, and primary productivity, during a past warm interval (Marine Isotope Stage 11, 424-374 ka). In general, sediments in the Bering Sea are hemipelagic, making them ideal deposits for paleoenvironmental reconstructions, but there is strong evidence in the grain size distribution for contourite deposits between ~408-400 ka at the slope sites, suggesting a change in bottom current transport at this time.We show that the grain size of coarse (>150 micrometers) terrigenous sediment can be used effectively as a proxy for ice rafting, although it is not possible to distinguish between iceberg and sea ice rafting processes, based on grain size alone. We find that the mean grain size of bulk sediments can be used to infer changes in productivity on glacial-interglacial timescales, but the size and preservation of diatom valves also exert a control on mean grain size. Lastly, we show that the mean size of sortable silt (10-63 micrometers) is not a valid proxy for bottom current strength in the Bering Sea, because the input of ice-rafted silt confounds the sortable silt signal.

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Pérez-Huerta, Alberto, Sally E. Walker, and Chiara Cappelli. "In Situ Geochemical Analysis of Organics in Growth Lines of Antarctic Scallop Shells: Implications for Sclerochronology." Minerals 10, no. 6 (June 10, 2020): 529. http://dx.doi.org/10.3390/min10060529.

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Bivalve shells are extensively used as bioarchives for paleoclimate and paleoenvironmental reconstructions. Proxy calibrations in recent shells are the basis for sclerochronology and the applications of geochemistry data to fossils. Shell geochemical information, however, could be altered with the disappearance of intercrystalline organic matrix components, including those linked to shell growth increments, during early diagenesis. Thus, an evaluation of the chemistry of such organics is needed for the correct use of sclerochronological records in fossil shells. Here, we use atom probe tomography (APT) for in situ geochemical characterization of the insoluble organic matrix in shell growth increments in the Antarctic scallop, Adamussium colbecki. We confirm the presence of carboxylated S-rich proteoglycans, possibly involved in calcite nucleation and growth in these scallops, with significant concentrations of magnesium and calcium. Diagenetic modification of these organic components could impact proxy data based on Mg/Ca ratios, but more importantly the use of the δ15N proxy, since most of the shell nitrogen is likely bound to the amide groups of proteins. Overall, our findings reinforce the idea that shell organics need to be accounted for in the understanding of geochemical proxies.

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Holcová, Katarína, and Attila Demeny. "The oxygen and carbon isotopic composition of Langhian foraminiferal tests as a paleoecological proxy in a marginal part of the Carpathian Foredeep (Czech Republic)." Geologica Carpathica 63, no. 2 (April 1, 2012): 121–37. http://dx.doi.org/10.2478/v10096-012-0010-x.

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The oxygen and carbon isotopic composition of Langhian foraminiferal tests as a paleoecological proxy in a marginal part of the Carpathian Foredeep (Czech Republic)Foraminiferal assemblages from three locations of the Moravian part of the Carpathian Foredeep (Kralice, Přemyslovice, Židlochovice) have been studied in order to determine the paleoenvironmental conditions during the Early Badenian (Middle Miocene). Paleobiological characteristics (plankton/benthos-ratio, relative abundances of warm-water plankton species, five-chamberedGloboturborotalitaspp.,Coccolithus pelagicusand high nutrient markers [benthos], test sizes and ranges ofGlobigerinasp. and cibicidoids, Benthic Foraminiferal Oxygen Index) were determined along with stable C and O isotope compositions. The stable isotope compositions show large variabilities indicating sample inhomogeneity in well preserved foraminiferal samples, interpreted as a sign of primary environmental variation and postmortem mixing of tests of different populations and sources. Based on the combined interpretation of paleobiological indicators and isotopic compositions, two theoretical models were established to describe the observed paleobiological and stable isotope data, that were used to categorize the locations studied. Several types of near-shore paleoenvironment were distinguished using the theoretical models: (i) bay influenced by seasonal phytodetritus supply from the continent (Kralice); (ii) dynamic shore characterized by variable isotopic compositions probably due to mixing of indigenous, transported and reworked tests (Přemyslovice); (iii) shore of alternating normal marine and continentally influenced environments (Židlochovice).

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Mîndrescu, Marcel, Alexandra Németh, Ionela Grădinaru, Árpád Bihari, Tibor Németh, József Fekete, Gábor Bozsó, and Zoltán Kern. "Bolătău sediment record – Chronology, microsedimentology and potential for a high resolution multimillennial paleoenvironmental proxy archive." Quaternary Geochronology 32 (April 2016): 11–20. http://dx.doi.org/10.1016/j.quageo.2015.10.007.

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Kuder, Tomasz, and Michael A. Kruge. "Preservation of biomolecules in sub-fossil plants from raised peat bogs — a potential paleoenvironmental proxy." Organic Geochemistry 29, no. 5-7 (November 1998): 1355–68. http://dx.doi.org/10.1016/s0146-6380(98)00092-8.

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Zilhão, João, Aurélie Ajas, Ernestina Badal, Christoph Burow, Martin Kehl, José Antonio López-Sáez, Carlos Pimenta, et al. "Cueva Antón: A multi-proxy MIS 3 to MIS 5a paleoenvironmental record for SE Iberia." Quaternary Science Reviews 146 (August 2016): 251–73. http://dx.doi.org/10.1016/j.quascirev.2016.05.038.

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Wei, Hai-Zhen, Fang Lei, Shao-Yong Jiang, Hua-Yu Lu, Ying-Kai Xiao, Han-Zhi Zhang, and Xue-Feng Sun. "Implication of Boron Isotope Geochemistry for the Pedogenic Environments in Loess and Paleosol Sequences of Central China." Quaternary Research 83, no. 1 (January 2015): 243–55. http://dx.doi.org/10.1016/j.yqres.2014.09.004.

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AbstractWe investigated the boron isotopic composition in loess–paleosol sequences in five different profiles in the Chinese Loess Plateau. Three possible boron sources are identified: atmospheric input, carbonates, and weathered silicate rocks. Variations of [Sr], [B], δ11B and the magnetic susceptibility correlate well with the pedogenetic intensity in three out of the five studied profiles, where pedogenesis under a cold–dry climate indicates lower δ11B, lower [B], lower magnetic susceptibility and higher [Sr] values. Exceptions to the variations between the δ11B and other known proxies were observed in arenaceous soils and the Red Clay sequence: the former suggested that vertical redistribution probably occurred with the boron migration, and the latter indicated an unknown mechanism of susceptibility enhancement. A better correlation between the δ11B and magnetic susceptibility and the quantitative estimation of boron budget from each source confirms the influence of paleoenvironmental changes on boron geochemical cycle. Significant positive correlations in Sr/Ca vs. B/Ca and Mg/Ca vs. B/Ca reflect consistent enrichment behavior of those mobile elements into calcium carbonate. The preliminary results imply that boron isotopic compositions in soils can be a potential geochemical proxy to reconstruct the paleoenvironmental changes in loess–paleosol sequences.

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Stuut, J. B. W., M. Marchant, J. Kaiser, F. Lamy, M. Mohtadi, O. Romero, and D. Hebbeln. "The late quaternary paleoenvironment of Chile as seen from marine archives." Geographica Helvetica 61, no. 2 (June 30, 2006): 135–51. http://dx.doi.org/10.5194/gh-61-135-2006.

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Abstract. Many variables have been used to reconstruct Chilean paleoenvironmental changes during the late Quaternary. In this paper we present an overview of a number of these variables, so-called proxies, that have been inferred from marine sediments from the Chilean continental margin and summarise the results. In general, a glacial-interglacial pattern of climate changes can be recognised in the proxy records with high-frequency variabilities superposed. The synthesis shows that the records in the Southeast Pacific are clearly dominated by a high-latitude climate forcing mechanism and that there is a noticeable gradual increase of tropical forcing moving from south to north along the South American continental margin.

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Machado, Maria J., Alfredo Pérez-González, and Gerardo Benito. "Paleoenvironmental Changes during the Last 4000 yr in the Tigray, Northern Ethiopia." Quaternary Research 49, no. 3 (May 1998): 312–21. http://dx.doi.org/10.1006/qres.1998.1965.

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In the Tigray region at the northern Ethiopian Highlands, paleoenvironmental reconstruction based on several infilled valley deposit sequences suggests that the past 4000 yr comprised three major wetter periods (ca. 4000–3500 yr B.P., 2500–1500 yr B.P., and 1000–960 yr B.P.), during which soils were formed, and two degradation episodes (ca. 3500–2500 yr B.P. and 1500–1000 yr B.P.), during which there was an increase of sediment yield from the slopes into the valleys. For the past 1000 yr, and in particular since the early 17th century, stratigraphic records together with historic chronicles suggest increasing aridity. Although difficulties arise in distinguishing between natural and human impacts, particularly in a region with a long established agricultural background, stratigraphical and proxy paleoclimatic data have indicated climate as the main controlling factor responsible for the environmental changes in the Tigray.

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Kiage, Lawrence M. "A 1200-year history of environmental changes in Bay Jimmy area, coastal Louisiana, USA." Holocene 30, no. 2 (September 14, 2019): 201–9. http://dx.doi.org/10.1177/0959683619875801.

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Paleoecological studies from the northern Gulf of Mexico (GOM) have mostly aimed at understanding long-term paleoenvironmental changes. Only a few studies have been performed in the southern United States focusing on paleoenvironmental changes during the common era. This study investigated paleoenvironmental changes in coastal Louisiana over the past 1200 years by utilizing proxy data, including loss-on-ignition (LOI) and pollen from a sediment core collected from a wetland in Bay Jimmy. The results indicate that the marsh in the study area was formed at ca. AD 1090 and has been primarily shaped by prevailing climatic conditions, including rare extreme events. At least four major hurricanes impacted the site over the 1200 years, including two that made landfall in recent times. The findings show that coastal Louisiana was warm and dry during the ‘Medieval Warm Period’ (ca. AD 950–1250). The environment after AD 1090 contained scattered Pinus and Juglans vegetation communities that were later succeeded by a closed forest that included Quercus and Morus. Red mangrove ( Rhizophora) was established in the vicinity of Bay Jimmy until shortly after cal AD 1450 and 1640. The pollen record indicates that the ‘Little Ice Age’ period (AD 1550–1850) was cold and dry, characterized by a more open vegetation community. There is evidence of forest disturbance that is marked by a rise in Ambrosia pollen in the 1700s, coinciding with the time of European settlement in North America. The presence of Ambrosia and Cheno/Am pollen throughout the record suggests that anthropogenic influence has been part of the fabric of the southern Louisiana landscapes throughout the 1200 years.

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Tribovillard, Nicolas, Viviane Bout-Roumazeilles, Marion Delattre, Sandra Ventalon, Romain Abraham, and Oussenatou Nzié. "Syndepositional glauconite as a paleoenvironmental proxy - the lower Cenomanian Chalk of Cap Blanc Nez (N-France)." Chemical Geology 584 (December 2021): 120508. http://dx.doi.org/10.1016/j.chemgeo.2021.120508.

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Weinstein-Evron, M., L. Weissbrod, A. Haber, and S. Chaim. "Decomposing biases in paleoenvironmental proxy data from pollen and micromammalian remains in caves: An actualistic approach." Palaeogeography, Palaeoclimatology, Palaeoecology 377 (May 2013): 86–101. http://dx.doi.org/10.1016/j.palaeo.2013.03.013.

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Cordova, Carlos E., and William C. Johnson. "An 18 ka to present pollen- and phytolith-based vegetation reconstruction from Hall's Cave, south-central Texas, USA." Quaternary Research 92, no. 2 (May 7, 2019): 497–518. http://dx.doi.org/10.1017/qua.2019.17.

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AbstractPollen, spores, phytoliths, and microscopic charcoal from a sedimentary column in Hall's Cave, south-central Texas, provide information for local and regional vegetation change during the last deglaciation and the Holocene in the context of broader regional and global climatic changes. The combination of paleoenvironmental proxy data from the cave indicates that between about 18,000 and 16,500 cal yr BP the cave area was dominated by an open plant community consisting of herbaceous vegetation, dominated by C3 grasses, and scattered trees, primarily Quercus and Pinus species. After about 16,500 cal yr BP, the arboreal component fluctuated, attaining a peak between 14,000 and 13,000 cal yr BP with relatively equal proportions of C3 and C4 grasses, including a sizable proportion of Panicoideae grasses. The Younger Dryas is marked by a conspicuous decrease in arboreal pollen with an apparent increase of C4 grasses toward its termination. Early Holocene recovery of arboreal vegetation is followed by a drying trend marked by the increasing dominance of C4 drought-tolerant Chloridoideae grasses. Increasing human use of the cave in middle to late Holocene times creates noise in the climatic significance of pollen, phytolith, and other proxies, a factor to consider when interpreting paleoenvironmental proxies in other cave sedimentary records.

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Cahill, Niamh, Andrew C. Kemp, Benjamin P. Horton, and Andrew C. Parnell. "A Bayesian hierarchical model for reconstructing relative sea level: from raw data to rates of change." Climate of the Past 12, no. 2 (February 29, 2016): 525–42. http://dx.doi.org/10.5194/cp-12-525-2016.

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Abstract. We present a Bayesian hierarchical model for reconstructing the continuous and dynamic evolution of relative sea-level (RSL) change with quantified uncertainty. The reconstruction is produced from biological (foraminifera) and geochemical (δ13C) sea-level indicators preserved in dated cores of salt-marsh sediment. Our model is comprised of three modules: (1) a new Bayesian transfer (B-TF) function for the calibration of biological indicators into tidal elevation, which is flexible enough to formally accommodate additional proxies; (2) an existing chronology developed using the Bchron age–depth model, and (3) an existing Errors-In-Variables integrated Gaussian process (EIV-IGP) model for estimating rates of sea-level change. Our approach is illustrated using a case study of Common Era sea-level variability from New Jersey, USA We develop a new B-TF using foraminifera, with and without the additional (δ13C) proxy and compare our results to those from a widely used weighted-averaging transfer function (WA-TF). The formal incorporation of a second proxy into the B-TF model results in smaller vertical uncertainties and improved accuracy for reconstructed RSL. The vertical uncertainty from the multi-proxy B-TF is ∼ 28 % smaller on average compared to the WA-TF. When evaluated against historic tide-gauge measurements, the multi-proxy B-TF most accurately reconstructs the RSL changes observed in the instrumental record (mean square error = 0.003 m2). The Bayesian hierarchical model provides a single, unifying framework for reconstructing and analyzing sea-level change through time. This approach is suitable for reconstructing other paleoenvironmental variables (e.g., temperature) using biological proxies.

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Cahill, N., A. C. Kemp, B. P. Horton, and A. C. Parnell. "A Bayesian hierarchical model for reconstructing relative sea level: from raw data to rates of change." Climate of the Past Discussions 11, no. 5 (October 16, 2015): 4851–93. http://dx.doi.org/10.5194/cpd-11-4851-2015.

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Abstract. We present a holistic Bayesian hierarchical model for reconstructing the continuous and dynamic evolution of relative sea-level (RSL) change with fully quantified uncertainty. The reconstruction is produced from biological (foraminifera) and geochemical (δ13C) sea-level indicators preserved in dated cores of salt-marsh sediment. Our model is comprised of three modules: (1) A Bayesian transfer function for the calibration of foraminifera into tidal elevation, which is flexible enough to formally accommodate additional proxies (in this case bulk-sediment δ13C values), (2) A chronology developed from an existing Bchron age-depth model, and (3) An existing errors-in-variables integrated Gaussian process (EIV-IGP) model for estimating rates of sea-level change. We illustrate our approach using a case study of Common Era sea-level variability from New Jersey. USA We develop a new Bayesian transfer function (B-TF), with and without the δ13C proxy and compare our results to those from a widely-used weighted-averaging transfer function (WA-TF). The formal incorporation of a second proxy into the B-TF model results in smaller vertical uncertainties and improved accuracy for reconstructed RSL. The vertical uncertainty from the multi-proxy B-TF is ∼ 28 % smaller on average compared to the WA-TF. When evaluated against historic tide-gauge measurements, the multi-proxy B-TF most accurately reconstructs the RSL changes observed in the instrumental record (MSE = 0.003 m2). The holistic model provides a single, unifying framework for reconstructing and analysing sea level through time. This approach is suitable for reconstructing other paleoenvironmental variables using biological proxies.

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Souto, Castro, García-Rodeja, and Pontevedra-Pombal. "The Use of Plant Macrofossils for Paleoenvironmental Reconstructions in Southern European Peatlands." Quaternary 2, no. 4 (October 1, 2019): 34. http://dx.doi.org/10.3390/quat2040034.

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The analysis of plant macrofossils in peatland ecosystems has been widely used for the climatic and ecological reconstruction of the Holocene in the high latitudes of the northern hemisphere. By contrast, perhaps associated with rarity of these ecosystems, this proxy has barely been explored for southern Europe. In this work, a compilation and review of existing knowledge on the study of plant macrofossils of peatlands in southern Europe has been carried out, both from a paleoenvironmental perspective and in terms of biodiversity dynamics. Although small in surface area, the peatlands of southern Europe stand out for their diversity (botanical, edaphogenic, morphological, etc.), which has allowed the recovery of a large number of macrofossils from both vascular plants and bryophytes. The southern zone of Europe contains refuge zones with a high plant diversity that have not suffered the intense glaciation of the northern zones, this allows a continuous record since the beginning of the Holocene and the detection of climatic events in lower latitudes, where the ice recession was earlier.

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Yanes, Yurena, María P. Asta, Miguel Ibáñez, María R. Alonso, and Christopher S. Romanek. "Paleoenvironmental implications of carbon stable isotope composition of land snail tissues." Quaternary Research 80, no. 3 (November 2013): 596–605. http://dx.doi.org/10.1016/j.yqres.2013.08.010.

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Land snail shell δ13C value is often used as a paleovegetation proxy assuming that snails ingest all plants in relation to their abundance, and that plants are the only source of carbon. However, carbonate ingestion and variable metabolic rates complicate these relationships. We evaluate if live-collected snails from Lanzarote (Canary Islands) reflect the abundance of C3 and CAM plants. Snails were collected on either CAM or C3 plants for isotope analysis of shell and body, and shell size. Respective shell and body δ13C values of snails collected on CAM plants averaged − 8.5 ± 1.7‰ and − 22.8 ± 1.6‰, whereas specimens from C3 plants averaged − 10.1 ± 0.7‰ and − 24.9 ± 1.1‰. A flux balance model suggests snails experienced comparable metabolic rates. A two-source mass balance equation implies that snails consumed ~ 10% of CAM, which agrees with their abundance in the landscape. Snails collected on CAM plant were smaller than those on C3 plants. Conclusively: 1) snails consume CAM plants when they are available; 2) migration of snails among C3 and CAM plants is a common phenomenon; and 3) C3 plants may be a more energetic food for growth than CAM plants. This study shows that shell δ13C values offer approximate estimates of plants in C3–CAM mixed environments.

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Izeta, Andrés D., Roxana Cattaneo, Andrés Robledo, and Julián Mignino. "Aproximación multiproxy a los estudios paleoambientales de la provincia de Córdoba: el Valle de Ongamira como caso." Revista del Museo de Antropología 10 (July 26, 2017): 33. http://dx.doi.org/10.31048/1852.4826.v10.n0.14401.

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El objetivo general de este trabajo es el de contribuir con nueva información arqueológica que aporte a un modelo paleoecológico general para las Sierras Pampeanas Australes desde un caso de estudio: el valle de Ongamira, donde han sido planteados cambios, discontinuidades y procesos de complejización durante el Holoceno. Se pretende asociar estos procesos a un marco paleoambiental con datos multi-proxy (dataciones absolutas por 14C y datos isotópicos asociados a estudios sedimentológicos, moluscos, microvertebrados y macro y micro-restos vegetales, entre otros). Abstract The aim of this work is to contribute with new archaeological information to the human paleoecology model for the Southern Pampean Hills from a case study: the valley of Ongamira, where changes, discontinuities and complexity processes arise throughout the Holocene. It is intended to associate these processes to a multi-proxy data generated paleoenvironmental framework using absolute dating by 14C and isotopic data associated with sedimentological studies, terrestrial gastropods shells, microvertebrates and macro and micro-debris from plants, among others.

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Kwiecien, Ola. "Paleoenvironmental changes in the Black Sea region during the last glacial and deglaciation: a multi-proxy approach." Quaternary International 279-280 (November 2012): 260. http://dx.doi.org/10.1016/j.quaint.2012.08.640.

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Peacock, Evan, and Jennifer L. Seltzer. "A comparison of multiple proxy data sets for paleoenvironmental conditions as derived from freshwater bivalve (Unionid) shell." Journal of Archaeological Science 35, no. 9 (September 2008): 2557–65. http://dx.doi.org/10.1016/j.jas.2008.04.006.

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Escudé, Élise, Élodie Renvoisé, Vincent Lhomme, and Sophie Montuire. "Why all vole molars (Arvicolinae, Rodentia) are informative to be considered as proxy for Quaternary paleoenvironmental reconstructions." Journal of Archaeological Science 40, no. 1 (January 2013): 11–23. http://dx.doi.org/10.1016/j.jas.2012.03.003.

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Wang, Rujian, Wenshen Xiao, Christian März, and Qianyu Li. "Late Quaternary paleoenvironmental changes revealed by multi-proxy records from the Chukchi Abyssal Plain, western Arctic Ocean." Global and Planetary Change 108 (September 2013): 100–118. http://dx.doi.org/10.1016/j.gloplacha.2013.05.017.

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Wilkinson, Keith N. "Colluvial deposits in dry valleys of southern England as proxy indicators of paleoenvironmental and land-use change." Geoarchaeology 18, no. 7 (September 11, 2003): 725–55. http://dx.doi.org/10.1002/gea.10090.

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McDonough, Katelyn N., Daniel G. Gavin, Richard L. Rosencrance, Loren G. Davis, Stephen C. Kuehn, Morgan F. Smith, Grant Snitker, Chantel V. Saban, and Ryan Szymanski. "Multi-proxy paleoenvironmental data from Paulina Marsh inform human-environmental dynamics in the Northern Great Basin U.S.A." Quaternary Science Advances 14 (June 2024): 100184. http://dx.doi.org/10.1016/j.qsa.2024.100184.

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Zhao, Xinnan, Jian Wang, Wei Zhao, and Hai Cheng. "Hydroclimate and Paleoenvironmental Variability from the Tonle Sap Lake Basin during the Angkor Period." Minerals 14, no. 6 (May 31, 2024): 581. http://dx.doi.org/10.3390/min14060581.

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The profound impact of the Khmer Empire on Southeast Asia renders the Angkor Period particularly significant in guiding contemporary societies to advocate and promote policies that respond to climate change. We present a new continuous multi-proxy speleothem dataset from Tonle Sap Lake Basin, investigating hydroclimate variability and the paleoenvironment of Cambodia during the Angkor Period from the 9th to 15th centuries. In addition, two important climatic events on a decadal scale are clearly reconstructed. The first is the reduction of precipitation between 800 and 1000 AD and the relatively significant drought that the regional environment may have experienced from 950 to 1000 AD. The second is the anomalous wet period between 1000 and 1200 AD, during which the Southern Oscillation Index also reached its negative peak after a thousand years. The wet and dry conditions are highly consistent with the El Niño-dominated and northward Intertropical Convergence Zone.

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Giaccio, B., E. Regattieri, G. Zanchetta, B. Wagner, P. Galli, G. Mannella, E. Niespolo, et al. "A key continental archive for the last 2 Ma of climatic history of the central Mediterranean region: A pilot drilling in the Fucino Basin, central Italy." Scientific Drilling 20 (December 17, 2015): 13–19. http://dx.doi.org/10.5194/sd-20-13-2015.

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Abstract. An 82 m long sedimentary succession was retrieved from the Fucino Basin, the largest intermountain tectonic depression of the central Apennines. The basin hosts a succession of fine-grained lacustrine sediments (ca. 900 m-thick) possibly continuously spanning the last 2 Ma. A preliminary tephrostratigraphy study allows us to ascribe the drilled 82 m long record to the last 180 ka. Multi-proxy geochemical analyses (XRF scanning, total organic/inorganic carbon, nitrogen and sulfur, oxygen isotopes) reveal noticeable variations, which are interpreted as paleohydrological and paleoenvironmental expressions related to classical glacial–interglacial cycles from the marine isotope stage (MIS) 6 to present day. In light of the preliminary results, the Fucino sedimentary succession is likely to provide a long, continuous, sensitive, and independently dated paleoclimatic archive of the central Mediterranean area.

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Park, Jungjae, Keun Bae Yu, Hyoun Soo Lim, and Young Ho Shin. "Multi-proxy evidence for late Holocene anthropogenic environmental changes at Bongpo marsh on the east coast of Korea." Quaternary Research 78, no. 2 (June 8, 2012): 209–16. http://dx.doi.org/10.1016/j.yqres.2012.05.003.

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AbstractWe present a multi-proxy record (pollen, microscopic charcoal, magnetic susceptibility, carbon-isotopic composition, total organic carbon [TOC], carbon/nitrogen [C/N] ratios, and particle size) of the late Holocene environmental change and human activities from Bongpo marsh on the east coast of Korea. Mutual interaction between the environment and humans during the late Holocene has not been properly investigated in Korea due to the lack of undisturbed samples with high sedimentation rates. In this study, the history of human responses to late Holocene environmental changes is clearly reconstructed using a multi-proxy paleoenvironmental approach that has not previously been applied in Korea. The evidence from Bongpo marsh indicates that 1) Bongpo marsh began to develop ca. 650 BC as a coastal lagoon was rapidly filled with organic matter, 2) agricultural disturbance around the study site remained slight until ca. AD 600, 3) full-scale intensive agriculture prevailed and the area of deforestation increased between ca. AD 600 and ca. AD 1870, and 4) the land use changed from lowland rice agriculture to upland cultivation when agricultural productivity declined after AD 1870, probably due to severe deforestation and the consequent heavy influx of clastic sediment on rice fields, as described in various historical documents.

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Bowen, Gabriel J., Kristine E. Nielson, and Timothy I. Eglinton. "Multi-Substrate Radiocarbon Data Constrain Detrital and Reservoir Effects in Holocene Sediments of the Great Salt Lake, Utah." Radiocarbon 61, no. 4 (June 14, 2019): 905–26. http://dx.doi.org/10.1017/rdc.2019.62.

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ABSTRACTThe radiocarbon (14C) content of simultaneously deposited substrates in lacustrine archives may differ due to reservoir and detrital effects, complicating the development of age models and interpretation of proxy records. Multi-substrate 14C studies quantifying these effects remain rare, however, particularly for large, terminal lake systems, which are excellent recorders of regional hydroclimate change. We report 14C ages of carbonates, brine shrimp cysts, algal mat biomass, total organic carbon (TOC), terrestrial macrofossils, and n-alkane biomarkers from Holocene sediments of the Great Salt Lake (GSL), Utah. 14C ages for co-deposited aquatic organic substrates are generally consistent, with small offsets that may reflect variable terrestrial organic matter inputs to the system. Carbonates and long-chain n-alkanes derived from vascular plants, however, are ∼1000–4000 14C years older than other substrates, reflecting deposition of pre-aged detrital materials. All lacustrine substrates are 14C-depleted compared to terrestrial macrofossils, suggesting that the reservoir age of the GSL was > 1200 years throughout most of the Holocene, far greater than the modern reservoir age of the lake (∼300 years). These results suggest good potential for multi-substrate paleoenvironmental reconstruction from Holocene GSL sediments but point to limitations including reservoir-induced uncertainty in 14C chronologies and attenuation and time-shifting of some proxy signals due to detrital effects.

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Leleu, Thomas, Valerie Chavagnac, Adelie Delacour, Catherine Noiriel, Georges Ceuleneer, Markus Aretz, Celine Rommevaux, and Sandra Ventalon. "Travertines Associated With Hyperalkaline Springs: Evaluation As A Proxy For Paleoenvironmental Conditions And Sequestration of Atmospheric CO 2." Journal of Sedimentary Research 86, no. 11 (November 2016): 1328–43. http://dx.doi.org/10.2110/jsr.2016.79.

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Faur, Luchiana, Virgil Drăgușin, Daniela Dimofte, Ferenc Lázár Forray, Maria Ilie, Constantin Marin, Cristian Mănăilescu, et al. "Multi-Proxy Study of a Holocene Soil Profile from Romania and Its Relevance for Speleothem Based Paleoenvironmental Reconstructions." Minerals 11, no. 8 (August 12, 2021): 873. http://dx.doi.org/10.3390/min11080873.

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In this study, we describe a sedimentary deposit situated above Ascunsă Cave (SW Romania) that should be in depositional connection with coeval stalagmites from the cave. We excavated a 2.5 m deep soil profile and took contiguous bulk samples every 5 cm. Soil samples were analyzed for clay mineralogy, grain size, chemical composition, magnetic susceptibility, and stable carbon isotopes. Radiocarbon dating revealed that the soil is of Holocene age, and presents a depositional hiatus between 5.4 and 2.3 thousand years before the present. Due to the open system behavior of soils and mobility of organic matter, a few hundred years of uncertainty should be considered for the duration of this hiatus. The fine fraction is dominated by silt, while the clay mineralogical association is made of illite, chlorite, kaolinite, vermiculite, and illite–vermiculite and illite–chlorite mixed layered minerals. The sediment source of this soil is represented by a nearby mélange complex, as well as by an underlying terra rossa-type soil. As this latter type of soil is widespread in our study area, we performed luminescence dating on two samples from a representative location close to our site and it appears that this type of Mediterranean soil was formed during the Last Interglacial period. δ13C variability in soil organic matter and a stalagmite from the cave are comparing well, and could help future studies identify modifications in isotopic fractionation processes within the cave.

Journal articles on the topic 'Proxy paleoenvironmental'

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