Peat bog archives of atmospheric metal deposition: geochemical evaluation of peat profiles, natural variations in metal concentrations, and metal enrichment factors

1996 ◽  
Vol 4 (2) ◽  
pp. 149-183 ◽  
Author(s):  
William Shotyk
Keyword(s):  
Atmospheric Deposition ◽  
Bulk Density ◽  
Human Activity ◽  
Metal Deposition ◽  
Geochemical Data ◽  
Peat Accumulation ◽  
Metal Concentrations ◽  
The Past ◽  
Natural Variations ◽  
Ombrotrophic Peat

The surface layers in ombrotrophic peat bogs are fed solely by atmospheric deposition; there is no chemical influence by groundwaters and other mineral soil waters. Bogs that have remained in this condition for the past hundreds or thousands of years may act as archival repositories of a wide variety of atmospheric constituents. Thus, peat cores taken from such bogs have the potential to provide detailed records of the changing rates of atmospheric metal deposition. However, not all bogs are appropriate for this type of investigation and the emphasis of this paper is on the geochemical factors that must be considered to select proper sites. Specifically, the objectives of this review are to (i) outline some of the geochemical characteristics that can be used to establish the existence of an ombrotrophic zone and illustrate the importance of this condition, (ii) provide examples of variations in bulk density and mineral matter contents and show how this can affect metal concentration profiles, and (iii) explain how natural variations in metal concentrations can be separated from anthropogenic inputs. Examples are taken mainly from two Sphagnum bogs in the Jura Mountains of Switzerland. At La Tourbière des Genevez (TGe), the geochemical properties of both the solid and aqueous phases indicate that there exists only a thin veneer of ombrotrophic peat, extending no deeper than 20 cm and representing less than 50 years of peat accumulation; the remainder of the profile is essentially minerotrophic. Here there is a striking natural As enrichment with increasing depth, which clearly shows the great danger in using inappropriate peat samples (such as those from peatlands that are mainly minerotrophic and whose metal budgets may be dominated by mineral-water interactions and groundwater flow patterns) for studying atmospheric processes. At Étang de la Gruyère (EGr), the geochemical data reveal an ombrotrophic layer that extends down to 250 cm and is estimated to represent 5000 years of peat accumulation. The uppermost 102 cm of this profile (core 2f) was studied in some detail and found to represent 2110 ± 30 years of peat formation. This core preserves the changing record of atmospheric Pb deposition since the Roman period. Normalizing metal concentrations to Sc provides an effective means to correct for variations in bulk density and ash content and to separate natural from anthropogenic metal inputs. In core 2f the minimum Pb/Sc ratios are at least seven times higher than the crustal ratio, showing that human activity has had a significant effect on the atmospheric Pb fluxes throughout the past 2110 years. The background Pb concentrations at EGr are found only at depths below 150 cm. The results from this profile emphasize the need to examine complete, ombrotrophic peat cores, not only to identify possible natural sources of the metals to the peat but also to quantify the true impact of human activity on atmospheric metal deposition.Key words: heavy metals, atmospheric deposition, peat cores, ombrotrophic bogs, historical records, Pb.

Atmospheric deposition of arsenic and selenium in ombrotrophic peat bogs

2003 ◽  
Vol 107 ◽  
pp. 1427-1427 ◽  
Author(s):  
J. Frank ◽  
M. Krachler ◽  
W. Shotyk
Keyword(s):  
Atmospheric Deposition ◽  
Peat Bogs ◽  
Ombrotrophic Peat

scholarly journals Lake-level variability in Salar de Coipasa, Bolivia during the past ∼40,000 yr

2018 ◽  
Vol 91 (2) ◽  
pp. 881-891 ◽  
Author(s):  
J. Andrew Nunnery ◽  
Sherilyn C. Fritz ◽  
Paul A. Baker ◽  
Wout Salenbien
Keyword(s):  
Lake Level ◽  
Sediment Accumulation ◽  
Geochemical Data ◽  
South American ◽  
Climate History ◽  
Oxygen Isotope Stage ◽  
The Past ◽  
History Of ◽  
Diatom Stratigraphy ◽  
The Last Glacial

AbstractVarious paleoclimatic records have been used to reconstruct the hydrologic history of the Altiplano, relating this history to past variability of the South American summer monsoon. Prior studies of the southern Altiplano, the location of the world’s largest salt flat, the Salar de Uyuni, and its neighbor, the Salar de Coipasa, generally agree in their reconstructions of the climate history of the past ∼24 ka. Some studies, however, have highly divergent climatic records and interpretations of earlier periods. In this study, lake-level variation was reconstructed from a ∼14-m-long sediment core from the Salar de Coipasa. These sediments span the last ∼40 ka. Lacustrine sediment accumulation was apparently continuous in the basin from ∼40 to 6 ka, with dry or very shallow conditions afterward. The fossil diatom stratigraphy and geochemical data (δ13C, δ15N, %Ca, C/N) indicate fluctuations in lake level from shallow to moderately deep, with the deepest conditions correlative with the Heinrich-1 and Younger Dryas events. The stratigraphy shows a continuous lake of variable depth and salinity during the last glacial maximum and latter stages of Marine Oxygen Isotope Stage 3 and is consistent with environmental inferences and the original chronology of a drill core from Salar de Uyuni.

scholarly journals Anti-Memorials and the Art of Forgetting: Critical Reflections on a Memorial Design Practice

2008 ◽  
Vol 15 ◽  
Author(s):  
SueAnne Ware
Keyword(s):  
Human Activity ◽  
The Other ◽  
Complex Spectrum ◽  
Design Practice ◽  
Design Work ◽  
The Past ◽  
Heroin Overdose ◽  
The Future ◽  
Changes Over Time ◽  
Over Time

Andreas Huyssen writes, ‘Remembrance as a vital human activity shapes our links to the past, and the ways we remember define us in the present. As individuals and societies, we need the past to construct and to anchor our identities and to nurture a vision of the future.’ Memory is continually affected by a complex spectrum of states such as forgetting, denial, repression, trauma, recounting and reconsidering, stimulated by equally complex changes in context and changes over time. The apprehension and reflective comprehension of landscape is similarly beset by such complexities. Just as the nature and qualities of memory comprise inherently fading, shifting and fleeting impressions of things which are themselves ever-changing, an understanding of a landscape, as well as the landscape itself, is a constantly evolving, emerging response to both immense and intimate influences. There is an incongruity between the inherent changeability of both landscapes and memories, and the conventional, formal strategies of commemoration that typify the constructed landscape memorial. The design work presented in this paper brings together such explorations of memory and landscape by examining the ‘memorial’. This article examines two projects. One concerns the fate of illegal refugees travelling to Australia: The SIEVX Memorial Project. The other, An Anti-Memorial to Heroin Overdose Victims, was designed by the author as part of the 2001 Melbourne Festival.

scholarly journals Conservation of the group Piperia (Orchidaceae) and associated plant communities

Lankesteriana ◽  
2015 ◽  
Vol 7 (1-2) ◽  
Author(s):  
Robert Lauri
Keyword(s):  
Plant Community ◽  
Plant Communities ◽  
Human Activity ◽  
Mediterranean Climate ◽  
The Past ◽  
The Mediterranean

The conservation and protection of California native orchids has not been a large focus recently. All California native orchids are terrestrial and many are associated with forest and woodland plant com- munities. However, a number are associated with the Mediterranean Climate plant community known as Chaparral; this includes at least three Piperia Rydb. species. Many Piperia populations and associated Chaparral plant communities have been impacted by human activity over the past several decades, howev- er, there is very little documentation regarding the size, and overall impact to the populations. 

scholarly journals Impact of climate change and human activity on the runoff in the upper reaches of the Shiyang River, Northwest China

2014 ◽  
Author(s):  
Peng Li ◽  
Jianhua Xu ◽  
Zhongsheng Chen ◽  
Benfu Zhao
Keyword(s):  
Climate Change ◽  
Human Activity ◽  
Climatic Factors ◽  
Meteorological Data ◽  
Northwest China ◽  
Potential Evaporation ◽  
The Past ◽  
Shiyang River Basin ◽  
Runoff Change ◽  
Increasing Trend

Based on the hydrological and meteorological data of the upper reaches of Shiyang River basin in Northwest China from 1960 to 2009, this paper analyzed the change in runoff and its related climatic factors, and estimated the contribution of climate change and human activity to runoff change by using the moving T test, cumulative analysis of anomalies and multiple regression analysis. The results showed that temperature revealed a significant increasing trend, and potential evaporation capacity decreased significantly, while precipitation increased insignificantly in the past recent 50 years. Although there were three mutations in 1975, 1990 and 2002 respectively, runoff presented a slight decreasing trend in the whole period. The contributions of climate change and human activity to runoff change during the period of 1976-2009 were 45% and 55% respectively.

Introduction

2015 ◽  
Author(s):  
Joanna D. Haigh ◽  
Peter Cargill
Keyword(s):  
Climate Change ◽  
Magnetic Field ◽  
Human Activity ◽  
The Sun ◽  
The Past ◽  
Key Features ◽  
Composition Structure ◽  
Earth’S Climate ◽  
Fundamental Requirement

This introductory chapter provides an overview of the Earth's climate system—its composition, structure, and circulation—and some of the ways in which these vary naturally with time. It examines the key features of the structure of the Sun, its magnetic field, atmosphere, and its emission of radiation and particles. A comprehension of how the sun affects the Earth is a fundamental requirement for understanding how climate has varied in the past and how it might change in the future. This is particularly important in the context of determining the cause(s) of climate change and understanding natural factors in order to be able to attribute to human activity any past or potential future influence on a range of timescales.

The Archaeology of Global Environment Change

2013 ◽  
Author(s):  
Carole L. Crumley
Keyword(s):  
Human Activity ◽  
Global Environmental Change ◽  
Earth System ◽  
Human Environment ◽  
The Past ◽  
The Earth ◽  
Global Environmental ◽  
Urgent Task ◽  
The Two Cultures ◽  
Non Linear System

Recent, widely recognized changes in the Earth system are, in effect, changes in the coupled human–environment system. We have entered the Anthropocene, when human activity—along with solar forcing, volcanic activity, precession, and the like—must be considered a component (a ‘driver’) of global environmental change (Crutzen and Stoermer 2000; Levin 1998). The dynamic non-linear system in which we live is not in equilibrium and does not act in a predictable manner (see Fairhead, chapter 16 this volume for further discussion of non-equilibrium ecology). If humankind is to continue to thrive, it is of utmost importance that we identify the ideas and practices that nurture the planet as well as our species. Our best laboratory for this is the past, where long-, medium-, and short-term variables can be identified and their roles evaluated. Perhaps the past is our only laboratory: experimentation requires time we no longer have. Thus the integration of our understanding of human history with that of the Earth system is a timely and urgent task. Archaeologists bring two particularly useful sets of skills to this enterprise: how to collaborate, and how to learn from the past. Archaeology enjoys a long tradition of collaboration with colleagues in both the biophysical sciences and in the humanities to investigate human activity in all planetary environments. Archaeologists work alongside one another in the field, live together in difficult conditions, welcome collaboration with colleagues in other disciplines—and listen to them carefully—and tell compelling stories to an interested public. All are rare skills and precious opportunities. Until recently few practitioners of biophysical, social science, and humanities disciplines had experience in cross-disciplinary collaboration. Many scholars who should be deeply engaged in collaboration to avert disaster (for example, specialists in tropical medicine with their counterparts in land use change) still speak different professional ‘languages’ and have very different traditions of producing information. C. P. Snow, in The Two Cultures (1993 [1959]), was among the first to warn that the very structure of academia was leading to this serious, if unintended, outcome.

11. Humans and mammals: the past and the future

2017 ◽  
pp. 128-138
Author(s):  
T. S. Kemp
Keyword(s):  
Human Activity ◽  
Mammalian Species ◽  
Mammalian Fauna ◽  
Mammal Species ◽  
The Past ◽  
The Future ◽  
Huge Impact

From the very start of the spread of humans, the world’s mammals have been irreversibly, and mostly detrimentally, affected through direct exploitation for food and for skins to make clothes and shelter. Our domestication of certain mammal species has also had a huge impact on the rest of the world’s mammalian fauna, and indeed on its whole biota. ‘Humans and mammals: the past and the future’ considers how human activity has caused the latest megafaunal extinction and looks at the future crisis facing many mammalian species. A quarter of mammalian species are, today, faced with severe population decreases that may result in extinction. What can be done to conserve them?

Ethics and politics in the Anthropocene

2020 ◽  
Vol 46 (10) ◽  
pp. 1167-1181 ◽  
Author(s):  
Maeve Cooke
Keyword(s):  
Climate Change ◽  
Human Activity ◽  
Land Degradation ◽  
Frankfurt School ◽  
Anthropogenic Climate Change ◽  
Considerable Evidence ◽  
The Past ◽  
Fundamental Challenge ◽  
Ecological Problems ◽  
Ethics And Politics

The most fundamental challenge facing humans today is the imminent destruction of the life-generating and life-sustaining ecosystems that constitute the planet Earth. There is considerable evidence that the strongest contemporary ecological threat is anthropogenic climate change resulting from the increasing warming of the atmosphere, caused by cumulative CO2 and other emissions as a result of collective human activity over the past few 100 years. This process of climate change is reinforced by further ecological problems such as pollution of land, air and sea, depletion of resources, land degradation and the loss of biodiversity. The name gaining currency for this emerging epoch of instability in the Earth’s eco-systems is the Anthropocene. Anthropogenic climate change calls for a categorical shift in thinking about the place of humanity in these systems and requires fundamental rethinking of ethics and politics. What would an appropriate ethical frame for politics in the Anthropocene look like? In response to this question, I sketch a proposal for an ethically non-anthropocentric ethics. I draw on early Frankfurt School Critical Theorists, and on Habermas, but move beyond these theorists in key respects.

The Pressure of the Past: Presidential Address.

1984 ◽  
Vol 50 ◽  
pp. 1-22 ◽  
Author(s):  
G. J. Wainwright
Keyword(s):  
Human Activity ◽  
Presidential Address ◽  
Vice President ◽  
Business Meeting ◽  
Annual Business ◽  
East Anglia ◽  
Inaugural Meeting ◽  
The Past ◽  
Fourth Decade ◽  
Selection Of

Fifty years ago on 17 February 1934 the Prehistoric Society of East Anglia held its annual business meeting in Norwich. Professor Breuil was elected President for that year, Professor Miles Burkitt as Vice-President and Dr J. G. D. Clark as Honorary Editor. Other elections at that meeting included Mr Stuart Piggott to Council and O. G. S. Crawford to membership of the Society. It had been founded in 1908 when on 17 October a circular had been issued by W. G. Clarke of Norwich and W. D. Dutt of Lowestoft to over 100 interested people inviting them to form an East Anglian Society of Prehistorians. That circular and a selection of replies to it still exist in the records of the Society that have recently been rediscovered. Dr W. A. Sturge of Icklingham Hall agreed to become the first President and, having received 72 favourable replies, an inaugural meeting was held on Monday 26 October 1908 at Norwich.For the better part of three decades the Society maintained an active, if somewhat parochial, role in the development of British Prehistory. Its interests were East Anglian in orientation and with little exception directed to the study of palaeolithic man and the flint implements that might (or might not) be ascribed to human activity.By 1930, however, some members of the Society were contemplating change. As C. S. Phillips (1980, 113) has pointed out, it was the only body in Britain devoted entirely to Prehistoric studies, but whilst its membership had originally been local to East Anglia, by the fourth decade of the century it was expanding outside the region.

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