Event stratigraphy is used to help characterise the Anthropocene as a chronostratigraphic concept, based on analogous deep-time events, for which we provide a novel categorization. Events in stratigraphy are distinct from extensive, time-transgressive 'episodes' – such as the global, highly diachronous record of anthropogenic change, termed here an Anthropogenic Modification Episode (AME). Nested within the AME are many geologically correlatable events, the most notable being those of the Great Acceleration Event Array (GAEA). This isochronous array of anthropogenic signals represents brief, unique events evident in geological deposits, e.g.: onset of the radionuclide 'bomb-spike'; appearance of novel organic chemicals and fuel ash particles; marked changes in patterns of sedimentary deposition, heavy metal contents and carbon/nitrogen isotopic ratios; and ecosystem changes leaving a global fossil record; all around the mid-20th century. The GAEA reflects a fundamental transition of the Earth System to a new state in which many parameters now lie beyond the range of Holocene variability. Globally near-instantaneous events can provide robust primary guides for chronostratigraphic boundaries. Given the intensity, magnitude, planetary significance and global isochroneity of the GAEA, it provides a suitable level for recognition of the base of the Anthropocene as a series/epoch.
The subalpine, atmospherically fed Śnieżka peatland, located in the Polish part of the Sudetes, is one of the nominated candidates for the GSSP of the Anthropocene. Data from two profiles, Sn1 (2012) and Sn0 (2020), from this site are critical for distinguishing the proposed epoch, while an additional core Sn2 is presented to support main evidence. The Sn0 archive contains a wide array of critical markers such as plutonium (Pu), radiocarbon (F 14 C), fly ash particles, Hg and stable C and N isotopes which are consistent with the previously well documented 210 Pb/ 14 C dated Sn1 profile, which provides a high-resolution and comprehensive database of trace elements and rare earth elements (REE), Pb isotopes, Pu, Cs, pollen and testate amoebae. The 1952 worldwide appearance of Pu, owing to its global synchronicity and repeatability between the cores, is proposed here as a primary marker of the Anthropocene, supported by the prominent upturn of selected chemostratigraphic and biostratigraphic indicators as well as the appearance of technofossils and artificial radionuclides.
The Isle of Man is a large island which lies in the middle of the northern Irish Sea between Britain and Ireland and, because of its insularity and size, has an impoverished flora compared with the two main islands. This has been the case throughout the postglacial and warrants the island’s description as a separate phytogeographic province. We have considered Holocene tree pollen data from seventeen sites on the island which together preserve a vegetation history that spans the six thousand years of the early and mid-postglacial from the end of the Lateglacial at 11,700 cal. BP to the mid-Holocene Ulmus decline at ca. 5800 cal. BP. Radiocarbon dating of the rational limits of the pollen curves for the main tree taxa has allowed an appraisal of the timing of each one’s expansion to become a significant component of the island’s woodland, and comparison with the dates of their expansion on the adjacent regions of Britain and Ireland. The radiocarbon dates show that, although some variability exists probably due to local factors, there is considerable concordance between the timings of major pollen zone boundaries in Britain and Ireland around the northern Irish Sea. On the Isle of Man the expansions of both Juniperus and Betula were delayed by several centuries compared to the British/Irish data, however the timing of the expansions of Corylus, Ulmus, Quercus, Pinus and Alnus on the Isle of Man all appear closely comparable to the ages for these pollen stratigraphic events in north Wales, northwest England, southwest Scotland and eastern Ireland, as are those for the Ulmus decline. It is likely that local pedological and edaphic factors on the island account for the differences in the first Holocene millennium, while regional climatic factors governed the timings for the rest of the expansions of tree taxa across the wider region, including the Isle of Man. Disturbance, including by human agency, was important at the site scale and perhaps triggered early tree expansion in some places, including Quercus, Ulmus and Alnus. Insularity seems not to have been a significant factor in the expansion of the major forest trees.
Over the past two decades there has been an increasing awareness of the need to develop a more energy efficient transportation system. This research explored the relationship between energy efficiency and transportation by analyzing the relationship between energy efficiency and specific aspects of transportation. This research analyzed the relationship between land use patterns and transportation energy use, urban congestion and excess energy use, local bus operations and energy efficiency, park-and-ride services and energy efficiency, and vehicle speeds in an urban environment and energy efficiency. This report also provides an example of an analysis of fuel efficiency and vehicle delay under various transportation scenarios in Houston, Texas. This research highlighted a number of findings that can have a significant impact on energy savings to the citizens of Texas. If the results of this research are utilized to develop policies that encourage energy efficient land development, and policies that encourage the placement of transit routes in corridors with favorable socioeconomic characteristics, increased energy efficiency may be expected to result. Similarly, if the findings of this research, which illustrate that fuel savings are associated with decreased congestion, provide the impetus for operational and other measures that reduce congestion to be implemented, then increased energy efficiency may be expected to result. Finally, if the methodology presented for the analysis of potential fuel savings is incorporated into procedures to analyze transportation alternatives, then significant energy savings may be expected to result.
The Mexico and Central American region has a history of mercury use that began at least two millennia before European colonisation in the 16th century. Archaeologists have reported extensive deposits of cinnabar (HgS) and other mercury materials in ancient human settlements across the region. However, there has been no consideration to date of the environmental legacy of this long history of anthropogenic mercury use. This review begins by synthesising our knowledge of the history and nature of anthropogenic mercury in ancient Mesoamerica based on archaeological data, with a particular focus on the Maya culture of lowland Guatemala, Belize, the Yucatan of Mexico, El Salvador, and Honduras. The Classic Period Maya used mercury for decorative and ceremonial (including funerary) purposes: Cinnabar (HgS) predominantly, but the archaeological record also shows rare finds of elemental mercury (Hg 0 ) in important burial and religious contexts. In this review, we have located and summarised all published data sets collected from (or near) ancient Maya settlements that include environmental mercury measurements. Comparing mercury determinations from pre-Columbian Maya settlements located across the region confirms that seven sites from ten have reported at least one location with mercury concentrations that equal or exceed modern benchmarks for environmental toxicity. The locations with elevated mercury are typically former Maya occupation areas used in the Late Classic Period, situated within large urban settlements abandoned by c. 10th century CE. It is most likely that the mercury detected in buried contexts at Maya archaeological sites is associated with pre-Columbian mercury use, especially of cinnabar. In more complex contexts, where modern biological or specifically anthropogenic inputs are more probable, legacy mercury in the environment will have a more complex, and time transgressive input history. This review identifies current research gaps in our understanding of the long history of Maya mercury use and in the collection of robust total mercury datasets from the Maya world. We identify important areas for future research on the environmental persistence and legacy of mercury, including the need to interpret environment mercury data in the context of mercury exposure and human health at Maya archaeological sites.
This is the final report to Natural England on Contract No: SAE03/02/054 ‘Using
novel palaeolimnological techniques to define lake conservation objectives’.
The primary objective of this project is to use existing and recently developed
palaeoecological techniques to define reference conditions and assess the condition
of selected SSSIs in England, and thereby to assist in the setting of conservation
objectives and management goals. The eight selected sites are Aqualate Mere,
Hawes Water (Silverdale), Cunswick Tarn, Over Water, Sunbiggin Tarn, Malham
Tarn, Semer Water and Hornsea Mere. The project is divided into four main tasks
with Task 1 essentially involving the collection, processing and dating of cores from
the study sites. To date only the latter has been funded and this report describes the
outputs of this task.