Pub Date : 2024-03-08DOI: 10.1007/s10933-024-00312-4
Matthew Kirby, Samuel K. Hippard, Lisa N. Martinez, Dahlia Serrato, Joseph Carlin, Nicole Bonuso, Sinan O. Akçiz, Christian Novich
In California, severe precipitation events (SPEs) are often associated with winter season atmospheric rivers. These SPEs can generate hurricane-scale precipitation, creating a variety of natural hazards such as floods and landslides. For California, the most complete SPE-flood record yet generated is a 9000-year paleoflood reconstruction from the Santa Barbara Basin (Du et al. in Mar Geol 397:29–42, 2018). Finding terrestrial counterparts to compare to the Santa Barbara Basin is a challenge in Southern California where lake basins are rare and the terrestrial spatiotemporal signature of SPE floods remains largely unconstrained. Here, we present five 1–2 m sediment cores from a sag pond along the San Andreas Fault in the southern Carrizo Plain. The most complete record (core CLPC21-4) was selected for a variety of chronological, sedimentological, and biological analyses. Principal Component Analysis on these data reveals two end member sediment unit types: event versus ambient sedimentation. We focus on the two thickest sediment units likely generated by SPEs. These two units (EU 1 and EU 2) are especially distinct within CLPC21-4, characterized by erosive bases, above average sand content, normal grading, low magnetic susceptibility, and low total organic matter. Moreover, they are visually apparent across all five cores within the sag pond and thin from source to sink. Age control for the two units is constrained by AMS 14C dates on discrete organic materials and supported by the identification of Erodium’s first appearance ca. 1750–1765 CE in the Santa Barbara region. Using these age constraints, we infer the maximum limiting age range for Event Unit 1 from 1470 to 1640 CE and Event Unit 2 from 1740 to 1800 CE. Within the limits of dating, site-specific proxy sensitivities, and inherent meteorological heterogeneity, we propose a probable correlation to Santa Barbara Basin flood events at 1525 CE and 1760 CE. Our results suggest that sag ponds may represent a viable and untapped paleoclimatic archive for California. Future work will focus on a latitudinal series of sag ponds to determine the spatiotemporal sequence and correlativity of SPEs in the sediment record.
{"title":"Little Ice Age flood events recorded in sag pond sediments in the Carrizo Plains National Monument, California","authors":"Matthew Kirby, Samuel K. Hippard, Lisa N. Martinez, Dahlia Serrato, Joseph Carlin, Nicole Bonuso, Sinan O. Akçiz, Christian Novich","doi":"10.1007/s10933-024-00312-4","DOIUrl":"https://doi.org/10.1007/s10933-024-00312-4","url":null,"abstract":"<p>In California, severe precipitation events (SPEs) are often associated with winter season atmospheric rivers. These SPEs can generate hurricane-scale precipitation, creating a variety of natural hazards such as floods and landslides. For California, the most complete SPE-flood record yet generated is a 9000-year paleoflood reconstruction from the Santa Barbara Basin (Du et al. in Mar Geol 397:29–42, 2018). Finding terrestrial counterparts to compare to the Santa Barbara Basin is a challenge in Southern California where lake basins are rare and the terrestrial spatiotemporal signature of SPE floods remains largely unconstrained. Here, we present five 1–2 m sediment cores from a sag pond along the San Andreas Fault in the southern Carrizo Plain. The most complete record (core CLPC21-4) was selected for a variety of chronological, sedimentological, and biological analyses. Principal Component Analysis on these data reveals two end member sediment unit types: <i>event</i> versus <i>ambient</i> sedimentation. We focus on the two thickest sediment units likely generated by SPEs. These two units (EU 1 and EU 2) are especially distinct within CLPC21-4, characterized by erosive bases, above average sand content, normal grading, low magnetic susceptibility, and low total organic matter. Moreover, they are visually apparent across all five cores within the sag pond and thin from source to sink. Age control for the two units is constrained by AMS <sup>14</sup>C dates on discrete organic materials and supported by the identification of <i>Erodium’s</i> first appearance ca. 1750–1765 CE in the Santa Barbara region. Using these age constraints, we infer the maximum limiting age range for Event Unit 1 from 1470 to 1640 CE and Event Unit 2 from 1740 to 1800 CE. Within the limits of dating, site-specific proxy sensitivities, and inherent meteorological heterogeneity, we propose a probable correlation to Santa Barbara Basin flood events at 1525 CE and 1760 CE. Our results suggest that sag ponds may represent a viable and untapped paleoclimatic archive for California. Future work will focus on a latitudinal series of sag ponds to determine the spatiotemporal sequence and correlativity of SPEs in the sediment record.</p>","PeriodicalId":16658,"journal":{"name":"Journal of Paleolimnology","volume":"19 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140075048","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-07DOI: 10.1007/s10933-024-00314-2
Nora Irene Maidana
The story I offer provides an intimate look at my passion and dedication to diatoms and Paleolimnology, narrating my journey from the first discoveries to my growth as a researcher in this field.
{"title":"Diatoms and paleolimnology: a lucky journey of no return","authors":"Nora Irene Maidana","doi":"10.1007/s10933-024-00314-2","DOIUrl":"https://doi.org/10.1007/s10933-024-00314-2","url":null,"abstract":"<p>The story I offer provides an intimate look at my passion and dedication to diatoms and Paleolimnology, narrating my journey from the first discoveries to my growth as a researcher in this field.</p>","PeriodicalId":16658,"journal":{"name":"Journal of Paleolimnology","volume":"298 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140075039","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-07DOI: 10.1007/s10933-024-00315-1
Harrison Stevens, Leon A. Barmuta, Zanna Chase, Krystyna M. Saunders, Atun Zawadzki, Patricia Gadd, Bernadette C. Proemse
Reports have shown that even remote lakes have been negatively affected by anthropogenic activities. This study used metal concentrations and enrichment factors to comprehensively determine key metal sources and identify potential impacts of recent anthropogenic activity in remote Central Highland Tasmanian (Australia) lakes. Metal concentrations (Al, As, Cd, Cu, Fe, Pb, and Zn) in these lakes remain below Australian interim sediment quality guidelines but have been slowly increasing since the start of the twentieth century. This increase is likely related to increasing organic matter content, rather than any direct, increased input of metals. The largest anthropogenic impact to these systems was damming, which typically led to an increase in organic matter content either directly, by the trapping of particles and nutrients, or indirectly, by stimulating primary production in the lake. This increased organic matter content, in turn, increased the retention of metals, manifesting as an increase to measured metal concentrations. Minor impacts are the historical use of lead shot, leaded petrol, and industrial processes, which may have contributed to the higher Pb enrichment, compared to the other studied metals, in these lakes. Despite recent concerns of metal contamination in the Tasmanian Wilderness World Heritage Area from distant mining activities, there is no strong evidence in this study indicating that lakes in the Central Highlands (a similar distance away) have been impacted by long-distance atmospheric deposition. This is likely related to the decreased rainfall, and thus decreased rates of wet deposition of aerosols in the east of Tasmania, compared to that of the west and in the Tasmanian Wilderness World Heritage Area.
{"title":"Identifying the key sources of metal (loid) deposition to remote Tasmanian lakes: is legacy mining a problem?","authors":"Harrison Stevens, Leon A. Barmuta, Zanna Chase, Krystyna M. Saunders, Atun Zawadzki, Patricia Gadd, Bernadette C. Proemse","doi":"10.1007/s10933-024-00315-1","DOIUrl":"https://doi.org/10.1007/s10933-024-00315-1","url":null,"abstract":"<p>Reports have shown that even remote lakes have been negatively affected by anthropogenic activities. This study used metal concentrations and enrichment factors to comprehensively determine key metal sources and identify potential impacts of recent anthropogenic activity in remote Central Highland Tasmanian (Australia) lakes. Metal concentrations (Al, As, Cd, Cu, Fe, Pb, and Zn) in these lakes remain below Australian interim sediment quality guidelines but have been slowly increasing since the start of the twentieth century. This increase is likely related to increasing organic matter content, rather than any direct, increased input of metals. The largest anthropogenic impact to these systems was damming, which typically led to an increase in organic matter content either directly, by the trapping of particles and nutrients, or indirectly, by stimulating primary production in the lake. This increased organic matter content, in turn, increased the retention of metals, manifesting as an increase to measured metal concentrations. Minor impacts are the historical use of lead shot, leaded petrol, and industrial processes, which may have contributed to the higher Pb enrichment, compared to the other studied metals, in these lakes. Despite recent concerns of metal contamination in the Tasmanian Wilderness World Heritage Area from distant mining activities, there is no strong evidence in this study indicating that lakes in the Central Highlands (a similar distance away) have been impacted by long-distance atmospheric deposition. This is likely related to the decreased rainfall, and thus decreased rates of wet deposition of aerosols in the east of Tasmania, compared to that of the west and in the Tasmanian Wilderness World Heritage Area.</p>","PeriodicalId":16658,"journal":{"name":"Journal of Paleolimnology","volume":"62 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140057631","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-05DOI: 10.1007/s10933-023-00309-5
Jose Esteban Castro
The article discusses the challenges and opportunities facing interdisciplinary attempts to produce knowledge about water and lake-related processes. It examines key aspects of the long-standing debates on this topic and discusses the state of the art providing empirical examples. The article argues that, notwithstanding the significant progress achieved in disciplines and fields of knowledge relevant to water-related research, the development of interdisciplinary coordination, particularly between the physical–natural and the social sciences remains underdeveloped. However, the fact that the extreme global crisis affecting water and life in the planet, more generally, has a primarily anthropogenic nature suggests that there are urgent reasons to promote greater collaboration between different forms of knowledge relevant to these processes. The main objective is contributing to raise awareness about obstacles and opportunities for enhanced interdisciplinary coordination in these areas, to tackle the urgent problems facing the socio-hydrosphere.
{"title":"Of lakes and knowledges: between disciplinary enclosures and the pursuit of “full transdisciplinarity”","authors":"Jose Esteban Castro","doi":"10.1007/s10933-023-00309-5","DOIUrl":"https://doi.org/10.1007/s10933-023-00309-5","url":null,"abstract":"<p>The article discusses the challenges and opportunities facing interdisciplinary attempts to produce knowledge about water and lake-related processes. It examines key aspects of the long-standing debates on this topic and discusses the state of the art providing empirical examples. The article argues that, notwithstanding the significant progress achieved in disciplines and fields of knowledge relevant to water-related research, the development of interdisciplinary coordination, particularly between the physical–natural and the social sciences remains underdeveloped. However, the fact that the extreme global crisis affecting water and life in the planet, more generally, has a primarily anthropogenic nature suggests that there are urgent reasons to promote greater collaboration between different forms of knowledge relevant to these processes. The main objective is contributing to raise awareness about obstacles and opportunities for enhanced interdisciplinary coordination in these areas, to tackle the urgent problems facing the socio-hydrosphere.</p>","PeriodicalId":16658,"journal":{"name":"Journal of Paleolimnology","volume":"54 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140035291","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-08DOI: 10.1007/s10933-023-00308-6
Godwin Okumagbe Aigbadon, Ezekiel Obinna Igwe, Obinna Chigoziem Akakuru, Azuka Ocheli, Brume Overare, Ikenna Arisi Obasi, Ernest Orji Akudo, Nosa Samuel Igbinigie, Mu’awiya Baba Aminu
Sedimentological and palynostratigraphy studies were used to evaluate sediment-stacking patterns in a depth range between 400 and 50 m in the Kemar-1 well section, Bornu (Chad) Basin, Nigeria. The greyish-sandy claystone, rich micaceous, lithified, and unlithified greyish claystone, dark well sorted micaceous sandstone, and poorly sorted and heterolithic clayey sandstones are the major facies components recognised in the well sections. The lithofacies characteristics were used to delineate and assign depositional environments ranging from lacustrine to fluvial settings. Paleoecological results revealed that the dominant palynofloral associations are angiosperm pollen and pteridophytic spores and they were tentatively grouped under three ecological groups which include freshwater, mangrove/brackish and savannah depositional environments in wet to dry climatic conditions during sediment formation. The presence of Echitricolporites spinosus was used to define the Echitricolporites spinosus palynological zone. The basal section at 390–385 m interval in the well shows the dominance of Psilatricolporites crassus, Verrucastosporites usmensis, and Monoporites annulatus, which marked the Eocene boundary from the overlying Miocene marker bed species of Echitricolporites spinosus, Grimsdalea magnaclavata, Anthocerus sp., Nymphaea lotus, and Retistephanocolpites gracilis. The palynomorph data and lithological characteristics from the studied well section have been used to establish that the Chad Formation is of late Eocene to early Miocene age, and that it unconformably overlies the Kerri–Kerri Formation that was deposited in varying lacustrine, fluvial and prograding shoreface and deltaic settings. This study has resolved the controversy surrounding the age of the Chad Formation, the challenge in depositional environment reconstruction. Finally, the stratigraphic framework of the Chad Formation in the study area is presented.
{"title":"Sedimentological, palynostratigraphic investigation and paleoenvironmental reconstruction of the Chad Formation, Bornu (Chad) Basin Nigeria","authors":"Godwin Okumagbe Aigbadon, Ezekiel Obinna Igwe, Obinna Chigoziem Akakuru, Azuka Ocheli, Brume Overare, Ikenna Arisi Obasi, Ernest Orji Akudo, Nosa Samuel Igbinigie, Mu’awiya Baba Aminu","doi":"10.1007/s10933-023-00308-6","DOIUrl":"https://doi.org/10.1007/s10933-023-00308-6","url":null,"abstract":"<p>Sedimentological and palynostratigraphy studies were used to evaluate sediment-stacking patterns in a depth range between 400 and 50 m in the Kemar-1 well section, Bornu (Chad) Basin, Nigeria. The greyish-sandy claystone, rich micaceous, lithified, and unlithified greyish claystone, dark well sorted micaceous sandstone, and poorly sorted and heterolithic clayey sandstones are the major facies components recognised in the well sections. The lithofacies characteristics were used to delineate and assign depositional environments ranging from lacustrine to fluvial settings. Paleoecological results revealed that the dominant palynofloral associations are angiosperm pollen and pteridophytic spores and they were tentatively grouped under three ecological groups which include freshwater, mangrove/brackish and savannah depositional environments in wet to dry climatic conditions during sediment formation. The presence of <i>Echitricolporites spinosus</i> was used to define the <i>Echitricolporites spinosus</i> palynological zone. The basal section at 390–385 m interval in the well shows the dominance of <i>Psilatricolporites crassus</i>, <i>Verrucastosporites usmensis</i>, and <i>Monoporites annulatus</i>, which marked the Eocene boundary from the overlying Miocene marker bed species of <i>Echitricolporites spinosus</i>, <i>Grimsdalea magnaclavata</i>, <i>Anthocerus</i> sp., <i>Nymphaea lotus</i>, and <i>Retistephanocolpites gracilis</i>. The palynomorph data and lithological characteristics from the studied well section have been used to establish that the Chad Formation is of late Eocene to early Miocene age, and that it unconformably overlies the Kerri–Kerri Formation that was deposited in varying lacustrine, fluvial and prograding shoreface and deltaic settings. This study has resolved the controversy surrounding the age of the Chad Formation, the challenge in depositional environment reconstruction. Finally, the stratigraphic framework of the Chad Formation in the study area is presented.</p>","PeriodicalId":16658,"journal":{"name":"Journal of Paleolimnology","volume":"13 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139415459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-12DOI: 10.1007/s10933-023-00307-7
Carsten Meyer-Jacob, Andrew L. Labaj, Andrew M. Paterson, Daniel Layton-Matthews, John P. Smol
Atmospheric acid deposition disrupted terrestrial-aquatic carbon cycling by drastically lowering dissolved organic carbon (DOC) loads in many lakes across NE North America and northern Europe during the 20th century. However, little is known about how acid deposition has altered the role of lakes as long-term carbon sinks. We present contemporary (n = 80) organic carbon accumulation rates (OCAR) and OCAR trends over the past ~ 150 years (n = 8), and other supporting infrared spectroscopic, isotopic, and elemental geochemical proxies, for lakes in and near Sudbury, Ontario, Canada – an area heavily affected by acid deposition from smelting activities in the late-19th and 20th centuries. Contemporary OCAR varied between 4.9 and 35.3 g m–2 yr–1 among study lakes (mean: 13.5±6.4 g m–2 yr–1). Sediment-inferred trends in lake-water DOC showed a strong response in DOC loadings to the effects of acid deposition during the past century, which is corroborated by increasing observed lake-water DOC concentrations (i.e., lake browning) since the 1980s. Despite these changes in DOC, as well as changes in water acidity, only lakes with direct physical watershed disturbances showed short-lived increases in OCAR, whereas OCAR changed little in remote Sudbury-region lakes with minimal direct human disturbances (mean OCAR: 14.3 ± 8.7 g m–2 yr–1). This is in stark contrast to many other northern forest lakes with minimal direct catchment disturbances that experienced significant increases in OCAR during the 20th century. Our results caution that lake browning may not be a dominant driver behind the widespread increase in organic C burial in northern lakes during recovery from acid deposition in recent decades.
20世纪,大气酸性沉降通过大幅降低北美东北部和北欧许多湖泊的溶解有机碳(DOC)负荷,破坏了陆水碳循环。然而,人们对酸沉积如何改变湖泊作为长期碳汇的作用知之甚少。我们提出了当代(n = 80)有机碳积累率(OCAR)和过去~ 150年(n = 8)的OCAR趋势,以及其他支持的红外光谱、同位素和元素地球化学指标,这些指标来自加拿大安大略省萨德伯里及其附近的湖泊,该地区在19世纪末和20世纪受到冶炼活动造成的酸沉积的严重影响。在研究湖泊中,当代OCAR在4.9和35.3 g m-2年- 1之间变化(平均值:13.5±6.4 g m-2年- 1)。沉积物推断的湖泊水中DOC趋势表明,在过去的一个世纪中,DOC负荷对酸沉积的影响有强烈的响应,自20世纪80年代以来观测到的湖泊水中DOC浓度(即湖泊褐变)的增加证实了这一点。尽管DOC和水酸度发生了这些变化,但只有受到直接流域物理干扰的湖泊OCAR出现了短期增加,而在直接人为干扰最小的偏远萨德伯里地区湖泊OCAR变化不大(平均OCAR: 14.3±8.7 g m-2年- 1)。这与许多其他北部森林湖泊形成鲜明对比,这些湖泊的直接集水区干扰最小,在20世纪经历了OCAR的显著增加。我们的研究结果提醒我们,湖泊褐变可能不是近几十年来北部湖泊酸性沉积恢复过程中有机碳埋藏广泛增加的主要驱动因素。
{"title":"Impacts of acid deposition and lake browning on long-term organic carbon storage in Canadian northern forest lakes","authors":"Carsten Meyer-Jacob, Andrew L. Labaj, Andrew M. Paterson, Daniel Layton-Matthews, John P. Smol","doi":"10.1007/s10933-023-00307-7","DOIUrl":"https://doi.org/10.1007/s10933-023-00307-7","url":null,"abstract":"<p>Atmospheric acid deposition disrupted terrestrial-aquatic carbon cycling by drastically lowering dissolved organic carbon (DOC) loads in many lakes across NE North America and northern Europe during the 20th century. However, little is known about how acid deposition has altered the role of lakes as long-term carbon sinks. We present contemporary (<i>n</i> = 80) organic carbon accumulation rates (OCAR) and OCAR trends over the past ~ 150 years (<i>n</i> = 8), and other supporting infrared spectroscopic, isotopic, and elemental geochemical proxies, for lakes in and near Sudbury, Ontario, Canada – an area heavily affected by acid deposition from smelting activities in the late-19th and 20th centuries. Contemporary OCAR varied between 4.9 and 35.3 g m<sup>–2</sup> yr<sup>–1</sup> among study lakes (mean: 13.5±6.4 g m<sup>–2</sup> yr<sup>–1</sup>). Sediment-inferred trends in lake-water DOC showed a strong response in DOC loadings to the effects of acid deposition during the past century, which is corroborated by increasing observed lake-water DOC concentrations (i.e., lake browning) since the 1980s. Despite these changes in DOC, as well as changes in water acidity, only lakes with direct physical watershed disturbances showed short-lived increases in OCAR, whereas OCAR changed little in remote Sudbury-region lakes with minimal direct human disturbances (mean OCAR: 14.3 ± 8.7 g m<sup>–2</sup> yr<sup>–1</sup>). This is in stark contrast to many other northern forest lakes with minimal direct catchment disturbances that experienced significant increases in OCAR during the 20th century. Our results caution that lake browning may not be a dominant driver behind the widespread increase in organic C burial in northern lakes during recovery from acid deposition in recent decades.</p>","PeriodicalId":16658,"journal":{"name":"Journal of Paleolimnology","volume":"287 1 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2023-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138630441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-02DOI: 10.1007/s10933-023-00305-9
Sida Fu, Jie Li, Patrick Rioual, Jingkang Wang, Luo Wang
The grain-size distribution of lake sediments is a crucial proxy for paleoclimate reconstruction, as it is closely related to the transport dynamics of clastic materials from the surrounding land. However, the presence of biogenic silica, particularly remains of diatom frustules, can significantly bias the grain-size distribution of lake-sediment samples. To remove this component, an alkaline solution, usually consisting of sodium carbonate, is commonly used during sample preparation. However, the efficiency of this method has not been fully verified under the microscope and with statistical tests. This study aims to assess the efficiency of removing diatoms from sediment samples under different concentrations and treatment durations of Na2CO3 solution, and with and without sonication. The removal efficiency was assessed using microscope examination. Two sets of sediment samples from Huguang Maar Lake with high contents of diatoms but different species compositions were used. Results show that increasing sodium carbonate concentration and treatment duration improved the removal efficiency. A treatment with 2 mol L−1 Na2CO3 solution coupled with ultrasound vibrations for 4 h was found to be the most effective method for removing biogenic silica from the lake-sediment samples that were investigated. Differences in the removal efficiency between the two samples might be due to the different dominant diatom species in the samples. The new method provides a more reliable and effective procedure for removing diatoms from lake-sediment samples.
{"title":"A new method to remove biogenic silica from lake sediments by chemical dissolution coupled with sonication","authors":"Sida Fu, Jie Li, Patrick Rioual, Jingkang Wang, Luo Wang","doi":"10.1007/s10933-023-00305-9","DOIUrl":"https://doi.org/10.1007/s10933-023-00305-9","url":null,"abstract":"<p>The grain-size distribution of lake sediments is a crucial proxy for paleoclimate reconstruction, as it is closely related to the transport dynamics of clastic materials from the surrounding land. However, the presence of biogenic silica, particularly remains of diatom frustules, can significantly bias the grain-size distribution of lake-sediment samples. To remove this component, an alkaline solution, usually consisting of sodium carbonate, is commonly used during sample preparation. However, the efficiency of this method has not been fully verified under the microscope and with statistical tests. This study aims to assess the efficiency of removing diatoms from sediment samples under different concentrations and treatment durations of Na<sub>2</sub>CO<sub>3</sub> solution, and with and without sonication. The removal efficiency was assessed using microscope examination. Two sets of sediment samples from Huguang Maar Lake with high contents of diatoms but different species compositions were used. Results show that increasing sodium carbonate concentration and treatment duration improved the removal efficiency. A treatment with 2 mol L<sup>−1</sup> Na<sub>2</sub>CO<sub>3</sub> solution coupled with ultrasound vibrations for 4 h was found to be the most effective method for removing biogenic silica from the lake-sediment samples that were investigated. Differences in the removal efficiency between the two samples might be due to the different dominant diatom species in the samples. The new method provides a more reliable and effective procedure for removing diatoms from lake-sediment samples.</p>","PeriodicalId":16658,"journal":{"name":"Journal of Paleolimnology","volume":"70 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2023-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138517838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-17DOI: 10.1007/s10933-023-00302-y
Colin J. Courtney-Mustaphi, Enrica Steiner, Stefanie von Fumetti, Oliver Heiri
Subfossil remains of aquatic invertebrates found in lacustrine sediments are useful paleoenvironmental indicators. Strongly scleroticized chitinous body parts from the exoskeleton or exuviae from invertebrates are often the most resistant to degradation during syn- and post-depositional processes. Invertebrate mandibles and body parts that superficially resemble mandibles, such as claw-like appendages and pygopodia, are frequently found in sieved Quaternary lacustrine, palustrine, and deltaic sediments. Guides, catalogs and atlases have been published that are well suited for the identification of subfossil remains for several invertebrate groups, such as chironomids, cladocerans, and ostracods, among others. However, aquatic invertebrate remains of several ecologically important invertebrate groups continue to be underused in paleoenvironmental studies, in part, because there are few visual keys or other documentation sources (e.g. descriptions, catalogs or atlases) that increase awareness and facilitate identification. Here we present sets of digital photomicrographs of pre-identified aquatic invertebrate specimens collected from streams, lakes and ponds that have been chemically cleared to preserve structures that are observed in subfossil remains in sieved sediment samples, commonly the > 100 μm size fractions. In addition, we present examples of these structures from Quaternary lake-sediment samples and cite the dispersed literature that demonstrate that these remains are preserved and remain identifiable in the fossil record. We document mandibles from several taxonomic groups that include Crustacea: Amphipoda, Isopoda, Ostracoda, and Notostraca; and Insecta orders: Coleoptera, Diptera, Ephemeroptera, Hemiptera, Odonata, Lepidoptera, Megaloptera, Plecoptera, and Trichoptera. The compilation of microphotographs also includes pygopodia and claw appendages of Plecoptera and Trichoptera, with additional images of other common invertebrate mouthpart and head remains. We describe several types of fossilizing structures that are, to our knowledge, not previously described in the paleoecological literature (e.g. mandibles of amphipods or plecopterans) but also show that some structures are considerably more variable than expected based on available descriptions, such as the mandibles of Ephemeroptera or Trichoptera, and that these can potentially be separated into different morphotypes useful for identification of subfossil material. We also discuss the potential of analyzing and interpreting the additional remains together with the remains of more commonly analyzed invertebrate groups (e.g. Chironomidae) to contribute to paleoenvironmental interpretations, which will allow assessments of functional groups (e.g. predators, shredders, grazers) or habitat types (e.g. littoral, profundal or lotic environments) that aquatic invertebrate remains originate from.
{"title":"Aquatic invertebrate mandibles and sclerotized remains in Quaternary lake sediments","authors":"Colin J. Courtney-Mustaphi, Enrica Steiner, Stefanie von Fumetti, Oliver Heiri","doi":"10.1007/s10933-023-00302-y","DOIUrl":"https://doi.org/10.1007/s10933-023-00302-y","url":null,"abstract":"<p>Subfossil remains of aquatic invertebrates found in lacustrine sediments are useful paleoenvironmental indicators. Strongly scleroticized chitinous body parts from the exoskeleton or exuviae from invertebrates are often the most resistant to degradation during syn- and post-depositional processes. Invertebrate mandibles and body parts that superficially resemble mandibles, such as claw-like appendages and pygopodia, are frequently found in sieved Quaternary lacustrine, palustrine, and deltaic sediments. Guides, catalogs and atlases have been published that are well suited for the identification of subfossil remains for several invertebrate groups, such as chironomids, cladocerans, and ostracods, among others. However, aquatic invertebrate remains of several ecologically important invertebrate groups continue to be underused in paleoenvironmental studies, in part, because there are few visual keys or other documentation sources (e.g. descriptions, catalogs or atlases) that increase awareness and facilitate identification. Here we present sets of digital photomicrographs of pre-identified aquatic invertebrate specimens collected from streams, lakes and ponds that have been chemically cleared to preserve structures that are observed in subfossil remains in sieved sediment samples, commonly the > 100 μm size fractions. In addition, we present examples of these structures from Quaternary lake-sediment samples and cite the dispersed literature that demonstrate that these remains are preserved and remain identifiable in the fossil record. We document mandibles from several taxonomic groups that include Crustacea: Amphipoda, Isopoda, Ostracoda, and Notostraca; and Insecta orders: Coleoptera, Diptera, Ephemeroptera, Hemiptera, Odonata, Lepidoptera, Megaloptera, Plecoptera, and Trichoptera. The compilation of microphotographs also includes pygopodia and claw appendages of Plecoptera and Trichoptera, with additional images of other common invertebrate mouthpart and head remains. We describe several types of fossilizing structures that are, to our knowledge, not previously described in the paleoecological literature (e.g. mandibles of amphipods or plecopterans) but also show that some structures are considerably more variable than expected based on available descriptions, such as the mandibles of Ephemeroptera or Trichoptera, and that these can potentially be separated into different morphotypes useful for identification of subfossil material. We also discuss the potential of analyzing and interpreting the additional remains together with the remains of more commonly analyzed invertebrate groups (e.g. Chironomidae) to contribute to paleoenvironmental interpretations, which will allow assessments of functional groups (e.g. predators, shredders, grazers) or habitat types (e.g. littoral, profundal or lotic environments) that aquatic invertebrate remains originate from.</p>","PeriodicalId":16658,"journal":{"name":"Journal of Paleolimnology","volume":"70 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2023-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138517854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-15DOI: 10.1007/s10933-023-00301-z
Elizabeth Bunin, Chengjun Zhang, Gonen Sharon, Steffen Mischke
Sedimentary records of environmental conditions retrieved from archeological sites provide valuable insight into the milieux of ancient humans and context to understand societal and cultural changes. At Jordan River Dureijat, an open-air site in Israel’s Hula Valley documenting the entire Epipaleolithic period as well as the Early Neolithic, sediments exposed on the walls of the excavation pit reveal a sequence of lacustrine deposits accumulated continuously between c. 21.1 and 11.3 cal ka BP near the southeast margin of Paleolake Hula. Through sediment-grain-size, geochemical, and paleontological analyses, we describe the nature of the Paleolake Hula from the Last Glacial Maximum (LGM) to the start of the Holocene. Until c. 17.2 cal ka BP, Paleolake Hula existed as a relatively large and well-buffered waterbody. A rapid and substantial drawdown of the lake occurred at 17.2 cal ka BP, followed by more frequent changes in the position of the shoreline in a smaller and shallower lake, resulting in the deposition of alternating near-shore and deeper lacustrine facies. Since the LGM, seven beds of structureless, silty sediments preserve archeological artifacts belonging to three Epipaleolithic cultures as well as the Early Neolithic pre-pottery Neolithic A culture. These sediments were deposited during phases of low lake level during which times humans waded into the shallow part of the lake, leaving behind stone and bone tools such as bladelets, lunates and burins, fishing hooks, line weights and net sinkers. Using radiocarbon-dated charcoal and a Bayesian statistical model, we produced a chronostratigraphic model for the archeological site, which enables the comparison of proxy paleoclimate records produced from this site’s sediments with regional archives as well as with global trends and changes in the Northern Hemisphere climate. Periods of low lake stands are correlated with the end of the LGM, Heinrich Event 1, and the beginning of the Younger Dryas Stadial. High water stands occurred contemporaneously with the peak of the LGM and during the Bølling–Allerød interstadial. This new water-level record from Lake Hula confirms that lake-level changes here broadly paralleled those of the Dead Sea and Sea of Galilee during the late Pleistocene, highlighting the importance of northern water sources to the overall water balance of the lakes along the Dead Sea Transform.
从考古遗址中检索到的环境条件的沉积记录为了解古代人类的环境和背景提供了宝贵的见解,以了解社会和文化的变化。在约旦河杜雷贾特,以色列胡拉谷的一个露天遗址,记录了整个旧石器时代和新石器时代早期,挖掘坑壁上暴露的沉积物揭示了古胡拉湖东南边缘附近约21.1至11.3 cal ka BP之间连续积累的一系列湖泊沉积物。通过沉积物粒度、地球化学和古生物学分析,我们描述了从末次盛冰期(LGM)到全新世开始的古胡拉湖的性质。直到公元前17.2 calka BP,古呼拉湖作为一个相对较大且缓冲良好的水体存在。17.2 cal ka BP发生了一次快速而明显的湖泊下降,随后在一个较小的较浅湖泊中,岸线位置发生了更频繁的变化,导致近岸和较深湖泊相交替沉积。自LGM以来,七层无结构的粉质沉积物保存了属于三个上石器时代文化以及新石器时代早期前陶器新石器时代A文化的考古文物。这些沉积物是在湖泊水位较低的时期沉积的,在此期间,人类涉水进入湖泊的浅水区,留下了石头和骨头的工具,如小片、月骨和烧痕、鱼钩、线重和网沉。利用放射性碳定年的木炭和贝叶斯统计模型,我们为考古遗址建立了一个年代地层模型,该模型可以将该遗址沉积物产生的代用古气候记录与区域档案以及北半球气候的全球趋势和变化进行比较。低湖林的时期与LGM的结束、Heinrich事件1和新仙女木时期的开始有关。高水位与LGM高峰同时出现,并在b ølling - allero ød间歇期出现。胡拉湖的新水位记录证实,在更新世晚期,这里的湖泊水位变化与死海和加利利海的变化大致相似,突出了北部水源对死海沿岸湖泊整体水平衡的重要性。
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Pub Date : 2023-11-10DOI: 10.1007/s10933-023-00306-8
Daniel Marchetti Maroneze, Rosa Maria Menendez, Daniela Rabello Ferreira, Diego Guimarães Florencio Pujoni, Paulo Alves de Lima Ferreira, Rubens Cesar Lopes Figueira, Paulina Maria Maia-Barbosa
{"title":"Paleolimnological evidence of the Inverted Trophic Cascade Hypothesis in a Neotropical lake","authors":"Daniel Marchetti Maroneze, Rosa Maria Menendez, Daniela Rabello Ferreira, Diego Guimarães Florencio Pujoni, Paulo Alves de Lima Ferreira, Rubens Cesar Lopes Figueira, Paulina Maria Maia-Barbosa","doi":"10.1007/s10933-023-00306-8","DOIUrl":"https://doi.org/10.1007/s10933-023-00306-8","url":null,"abstract":"","PeriodicalId":16658,"journal":{"name":"Journal of Paleolimnology","volume":"112 42","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135136926","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}