A 2000-year environmental history of Jackson Hole, Wyoming, inferred from lake-sediment records

During the late Quaternary, the Jackson Hole area has reen repeatedly glaciated-the most recent and least extensive ice advance occurred during the Pinedale Glaciation (ca. 25,000-9,000 yr B.P.; Love and Reed, 1971). The objective of this research is to study the vegetation history of Jackson Hole since Pinedale time, as a means of interpreting the development and stability of modern plant communities. The research is based on an examination of pollen and plant-macrofossiil records contained in lake-sediment cores collected near the former ice margin. The environmental history of this region is poorly known and the paleoecological information provided by this study should help fill a gap in our understanding of the vegetation, climate, and glacial history of the Northern Rocky Mountains.

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Towards a history of Holocene P dynamics for the Northern Hemisphere using lake sediment geochemical records

Biogeosciences ◽

10.5194/bg-18-5609-2021 ◽

2021 ◽

Vol 18 (20) ◽

pp. 5609-5638

Author(s):

Madeleine Moyle ◽

John F. Boyle ◽

Richard C. Chiverrell

Keyword(s):

Lake Sediment ◽

Northern Hemisphere ◽

Lake Water ◽

Landscape Development ◽

Development History ◽

P Cycling ◽

Sediment Records ◽

History Of ◽

P Supply

Abstract. Present-day lake water phosphorus (P) enrichment and accelerated P cycling are changes superimposed on a dynamic Holocene history of landscape development following glaciation, changes in climate, and long-term low-intensity human activity. Knowledge of the history of long-term P dynamics is essential for understanding present-day landscape P export and for managing both terrestrial and aquatic environments. This study is the first attempt to constrain the timing and magnitude of terrestrial changes in Holocene P dynamics across the Northern Hemisphere using lake sediment records. Here we reconstruct trajectories in terrestrial Holocene P dynamics for the Northern Hemisphere. We apply a simple process model to published lake sediment geochemical P records from 24 sites, producing records of landscape P yield and reconstructing lake water total phosphorus (TP) concentrations. Individual site trajectories of landscape P yield and lake water TP vary systematically, with differences attributable to local landscape development history. Three distinct traits are apparent. Mountain sites with minimal direct human impact show falling P supply and conform to conceptual models of natural soil development (Trait 1). Lowland sites where substantial (pre-)historic agriculture was present show progressively increasing P supply (Trait 2). Lowland sites may also show a rapid acceleration in P supply over the last few centuries, where high-intensity land use, including settlements and farming, is present (Trait 3). Where data availability permitted comparison, our reconstructed TP records agree well with monitored lake water TP data, and our sediment-inferred P yields are comparable to reported catchment export coefficients. Comparison with diatom-inferred TP reveals good agreement for recent records. Our reconstructions form the first systematic assessment of average terrestrial P export for the Northern Hemisphere over the Holocene and provide the empirical data needed for constraining long-term landscape P cycling models and values for terrestrial P export that could be used for ocean P cycling models. The long-term perspective provided by our sediment-inferred TP can be used to identify pre-disturbance baselines for lake water quality, information essential to target-driven lake management. We find the first detectable anthropogenic impacts on P cycling ca. 6000 BP, with more substantial impacts as early as 3000 BP. Consequently, to characterize pre-disturbance lake P conditions at Trait 2 and Trait 3 sites, it is necessary to consider time periods before the arrival of early farmers. Our use of trait classifications has a predictive power for sites without sediment records, allowing prediction of TP baselines and P trajectories based on regional landscape development history.

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LAKE SEDIMENT BASED INSIGHT INTO THE DEGLACIATION AND POST-GLACIAL CLIMATE AND ENVIRONMENTAL HISTORY OF THE MEALY MOUNTAINS, SOUTHEASTERN LABRADOR, CANADA

10.1130/abs/2016ne-272909 ◽

2016 ◽

Author(s):

James LeNoir ◽

◽

Timothy L. Cook

Keyword(s):

Environmental History ◽

Lake Sediment ◽

History Of ◽

Insight Into ◽

Glacial Climate

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Impact of urban development on waterbodies during medieval and early modern ages in Bad Waldsee (Germany)

10.5194/egusphere-egu21-9168 ◽

2021 ◽

Author(s):

Kristin Haas ◽

Kim J. Krahn ◽

Sara Saeidi Ghavi Andam ◽

Rik Tjallingii ◽

Matthias Hinderer ◽

...

Keyword(s):

Water Quality ◽

Environmental History ◽

Human Impact ◽

Sediment Cores ◽

Reference Conditions ◽

Urban Centre ◽

Lake Ecosystems ◽

Sediment Records ◽

History Of ◽

The City

<p>Seasonally laminated lacustrine sediments of Lake Stadtsee, located in the city of Bad Waldsee (Southern Germany), offer a continuous archive that allows a unique and yearly correlation of sedimentary signals and historic documents since medieval times. Comparison of the economic and environmental history of an urban centre will provide detailed insight into how the history of a city and its periphery region affected lake development and water quality, and how fast water quality and aquatic ecosystem recovered from human impact and activities. An interdisciplinary research team consisting of geologists, biologists, and historians from various universities and institutions has been established and started its work recently. The common goal of the different working groups and disciplines is to investigate temporally highly resolved sediment records of diatom and pollen spectra, geochemical proxies, and sediment facies of profundal sediment cores from Lake Stadtsee and to compare and calibrate these results with historic documents, stock books, archive records, dendrochronology records, and maps. So far, continuous geochemical sediment records of Lake Stadtsee were acquired non-destructively using X-ray fluorescence (XRF) core scanning. These element intensity records of the major elements (e.g. Al, Si, K, Ca, Ti, Fe) were measured every 2 mm. Sampling and subsequent analyses (e.g. pollen, PAH, isotopes) are ongoing.</p><p>Overall, the environmental impact of socio-economic development for the preindustrial development phase of a city from AD 1200 to 1800 will be assessed for the first time. The research will focus on the effects of population growth or decrease, farming intensity, economic production, trade activity in relation to environmental, and climate change, including catastrophic events such as fires and floods. The results will provide important insights about the response of urban surface waters to changing emissions of the city and the long-term behaviour of persistent pollutants on lakes. The project will thereby contribute to the knowledge of historic human impact on the environment in Germany, pre-medieval reference conditions, and the limits of resilience of aquatic systems. Thus, it will target the past environmental footprint of anthropogenic induced events on urbanized lake ecosystems and help to understand the mechanism behind such processes in the future.</p>

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Towards a history of Holocene P dynamics for the northern hemisphere using lake sediment geochemical records

10.5194/bg-2021-86 ◽

2021 ◽

Author(s):

Madeleine Moyle ◽

John Francis Boyle ◽

Richard Christopher Chiverrell

Keyword(s):

Lake Sediment ◽

Northern Hemisphere ◽

Lake Water ◽

Landscape Development ◽

Development History ◽

P Cycling ◽

Sediment Records ◽

History Of ◽

P Supply

Abstract. Present day lake water phosphorus (P) enrichment and accelerated P cycling are changes superimposed on a dynamic Holocene history of landscape recovery from glaciation, changes in climate, and long-term low-intensity human activity. Knowledge of the history of long-term P dynamics is essential for understanding present-day landscape P export and for managing both terrestrial and aquatic environments. This study is the first attempt to constrain the timing and magnitude of terrestrial changes in Holocene P dynamics across the Northern Hemisphere using lake sediment records. Here we reconstruct trajectories in terrestrial Holocene P dynamics for the Northern Hemisphere. We apply a simple process model to published lake sediment geochemical P records from 24 sites, producing records of landscape P yield and reconstructing lake water total phosphorus (TP) concentrations. Individual site trajectories of landscape P yield and lake water TP vary systematically, with differences attributable to local landscape development history. Three distinct traits are apparent. Mountain sites with minimal direct human impact show falling P supply and conform to conceptual models of natural soil development (Trait 1). Lowland sites where substantial (pre-)historic agriculture was present show progressively increasing P supply (Trait 2). Lowland sites may also show a rapid acceleration in P supply over the last few centuries, where high intensity land use, including settlements and farming, are present (Trait 3). Where data availability permitted comparison, our reconstructed TP records agree well with both monitored lake water TP data and diatom inferred TP, and our sediment inferred P yields are comparable to reported catchment export coefficients. Our reconstructions form the first systematic assessment of average terrestrial P export for the Northern Hemisphere over the Holocene and provide the empirical data needed for constraining long-term landscape P cycling models and values for terrestrial P export that could be used for ocean P cycling models. The long-term perspective provided by our sediment-inferred TP can be used to identify pre-disturbance baselines for lake water quality, information essential to target-driven lake management. We find the first detectable anthropogenic impacts on P cycling ca. 6000 BP, with more substantial impacts as early as 3000 BP. Consequently, to characterise pre-disturbance lake P conditions at Trait 2 and Trait 3 sites it is necessary to consider time periods before the arrival of early farmers. Our use of trait classifications has a predictive power for sites without sediment records, allowing prediction of TP baselines and P trajectories based on regional landscape development history.

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