Regional to global correlation of Eocene–Oligocene boundary transition successions using biostratigraphic, geophysical and geochemical methods

AbstractRegional to global high-resolution correlation and timing is critical when attempting to answer important geological questions, such as the greenhouse to icehouse transition that occurred during the Eocene–Oligocene boundary transition. Timing of these events on a global scale can only be answered using correlation among many sections, and multiple correlation proxies, including biostratigraphy, lithostratigraphy, geochemistry and geophysical methods. Here we present litho- and biostratigraphy for five successions located in the southeastern USA. To broaden the scope of correlation, we also employ carbon and oxygen stable isotope and magnetic susceptibility (χ) data to interpret these sections regionally, and correlate to the Global Boundary Stratotype Section and Point (GSSP) near Massignano in central Italy. Our results indicate that approaching the Eocene–Oligocene boundary, climate warmed slightly, but then δ18O data exhibit an abrupt c. +5 ‰ positive shift towards cooling that reached a maximum c. 1 m below the boundary at St Stephens Quarry, Alabama. This shift was accompanied by a c. −3 ‰ negative shift in δ13C interpreted to indicate environmental changes associated with the onset of the Eocene–Oligocene boundary planktonic foraminiferal extinction event. The observed cold pulse may be responsible for the final extinction of Hantkeninidae, used to define the beginning of the Rupelian Stage. Immediately preceding the boundary, Hantkeninidae species dropped significantly in abundance and size (pre-extinction dwarfing occurring before the final Eocene–Oligocene extinctions), and these changes may be the reason for inconsistencies in past Eocene–Oligocene boundary placement in the southeastern USA.

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The Holocene record of environmental changes in the ‘Stagno di Maccarese’ marsh (Tiber river delta, central Italy)

The Holocene ◽

10.1177/0959683612455543 ◽

2012 ◽

Vol 22 (12) ◽

pp. 1461-1471 ◽

Cited By ~ 7

Author(s):

C Giraudi

Keyword(s):

Environmental Changes ◽

Central Italy ◽

Global Scale ◽

Beach Ridges ◽

The Holocene ◽

Tiber River ◽

Environmental Variations ◽

Holocene Record ◽

The 19Th Century ◽

Ird Events

The stratigraphic study of the Stagno di Maccarese, carried out on the sediments exposed in about 7 km of trenches excavated in an area of approximately 1.5 km2, has shown that in the course of the Holocene many environmental variations have taken place. The complex evolution of the marsh is demonstrated by the variations in water salinity and the presence of erosion surfaces and soils between the sediments. In the early Holocene, the area studied was an isolated marsh with water having variable salinity, and it was only about 6000 cal. yr BP that it was encompassed in the system of inner delta marshes. In the delta environment, the water of the marsh was oligohaline until about 9th–8th centuries bc, brackish from 9th–8th centuries bc to about 600 yr BP, and later oligohaline until the 19th century drainage. A number of environmental variations are connected with local phenomena, such as erosion of the beach ridges and Tiber floods, but the others can be correlated chronologically with climatic events recorded at regional and global scale. The millennial variations seem to be connected with changes in insolation, while abrupt variations can be correlated chronologically with the IRD events dated at 8200, 5900, 4200, 2800, 1400 and 500 cal. yr BP.

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Geology and geophysics at the archeological park of Vulci (central Italy)

Annals of Geophysics ◽

10.4401/ag-6361 ◽

2014 ◽

Vol 57 (1) ◽

Author(s):

Marco Marchetti ◽

Vincenzo Sapia ◽

Adriano Garello ◽

Donatella De Rita ◽

Alessandra Venuti

Keyword(s):

Electrical Resistivity ◽

Magnetic Susceptibility ◽

Cultural Heritage ◽

Central Italy ◽

Geophysical Methods ◽

Archaeological Sites ◽

Local Authorities ◽

Resistivity Tomography ◽

Geological Information ◽

Geological Map

<p>The Vulci archeological site was object of interest by the Soprintendenza ai beni culturali dell’Etruria meridionale (Italian government department responsible for southern Etruria’s cultural heritage) since the beginning of the 20th century. In 2001, the Ministero dei Beni Culturali (Italian ministry of cultural heritage) along with the local authorities, opened a natural-archeological park. In this area, it lies most of the ancient Etruscan city of Velch (today known by its Latin name, Vulci) including the Osteria Necropolis that is the object of this study. Recently, new archaeological excavations were made and the local authorities needed major geological information about the volcanic lithotypes where the Etruscans used to build their necropolis. The aim of this study is to define the geological and geophysical characteristics of the rock lithotypes present in the Vulci park. For this purpose, a geological map of the area (1:10000) has been realized. Moreover, two different geophysical methods were applied: measurements of magnetic susceptibility and electrical resistivity tomography. Magnetic susceptibility analyses clearly identify magnetic contrasts between different lithotypes; the characteristics of the pyroclastic flow that originated the Sorano unit 2 and its vertical facies variations are well recorded by this parameter that along with lithostratigraphic observations provides information about the depositional conditions. Two electrical resistivity tomographies were performed, which show the Sorano unit 2 thickness to be of c. 7 m with resistivity values ranging from 200 to 400 Ω·m. This kind of multidisciplinary approach resulted to be suitable to study this type of archaeological sites, revealing that areas characterized by a relevant thickness and wide areal extension of volcanic lithotypes can be a potential site where Etruscans might have excavated their necropolis.</p>

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Thinning of the Quelccaya Ice Cap over the last thirty years

10.5194/tc-2016-40 ◽

2016 ◽

Cited By ~ 3

Author(s):

C. D. Chadwell ◽

D. R. Hardy ◽

C. Braun ◽

H. H. Brecher ◽

L. G. Thompson

Keyword(s):

Unit Volume ◽

Environmental Changes ◽

Statistical Significance ◽

Geophysical Methods ◽

Snow Accumulation ◽

Dual Frequency ◽

The Past ◽

Ice Cap ◽

Ice Surface ◽

Quelccaya Ice Cap

Abstract. Direct measurements of the decadal response of Tropical glaciers to environmental changes are difficult to acquire within their accumulation zones. In 2013, we used dual-frequency kinematic GPS to re-measure the surface elevations at 46 sites, from the margin to across the summit of the Quelccaya Ice Cap, first measured in 1983 using terrestrial surveying methods. In 2015, six additional sites on the western margin, first observed in 1978, were remeasured. Over the past 30 years, the ice cap summit has thinned by 4.41 &pm; 0.23 m (2σ), with a maximum ice loss at one site near the margin of 63.4 &pm; 0.34 m (2σ) over 37 years. Using geophysical methods that located the sub-glacial bedrock, we estimate the unit-volume of ice in 1983 along a profile from the 1983 margin to the summit and then the change in volume from 1983 to 2013 by differencing the surface elevations. Over the past 30 years, 21.2 &pm; 0.3 % (2σ) of the ice unit-volume has been lost suggesting an average annual mass balance rate of −0.5 &pm; 0.1 m w.e. a−1 (2σ). Increasing air temperature at high elevations of the Andes is likely a major driver of the observed changes. Specifically, within the ablation zone, thinning is likely caused by a 1–2 m w.e. a−1 increase in melting and sublimation above steady-state.Within the accumulation zone, analysis of annual, dry-season summit pits suggests that surface lowering may be caused by both a slight decrease in net snow accumulation and an increase in firnification rate, though this interpretation yet lacks statistical significance. The role of ice flux changes since 1983/4 remains unconstrained, awaiting updated measurements of ice surface velocities across the ice cap.

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Ubiquitous Computing for Microbial Forensics and Bioterrorism

Risk Assessment and Management in Pervasive Computing ◽

10.4018/978-1-60566-220-6.ch005 ◽

2011 ◽

pp. 86-101

Author(s):

Gaya Prasad

Keyword(s):

Ubiquitous Computing ◽

Environmental Changes ◽

Database Systems ◽

Global Scale ◽

Genetically Engineered ◽

Microbial Diseases ◽

High Resolution Data ◽

Microbial Forensics ◽

Genetically Engineered Bacteria ◽

Diverse Data

Microorganisms are ubiquitous in their presence. They are present in air, soil, water, and all kinds of living creatures. Varieties of microbes have been linked to diseases of humans, animals, and plants. Advances in molecular biology, electronics, nanotechnology, computer sciences, and information technology have made it possible to hybridize these to create ubiquitous devices and biosensors that would indicate presence of microbial agents in water, foods, air, hospitals, animal farms, and other environments. Analyses of microbial genomes and phylogenies have become increasingly important in the tracking and investigation of events leading to spread of microbial diseases and biocrimes. The capability of microorganisms to communicate with similar as well as different microorganisms, the ability to react to the environmental changes, and most of all, the intelligence to manage themselves without the need for supervision during deployment and operation; makes them attractive agents for use in Biosensors. Biosensors such as genetically engineered bacteria have been proven useful. It appears possible to develop biosensors that could detect the presence of biocrime/bioterror agents in diverse environments. Ubiquitous computing technology has the potential to develop integrated small devices which could detect bioterrorism agents. Similarly, pervasive computing could be a tool to monitor the microbial pollution in water, milk, and other edible commodities. Microbial forensics has become an important field for research and development due to increased threats of biocrimes. Microbial forensics requires utilization of diverse data that are acquired through standard processes in distributed locations. Technologies for data production are evolving rapidly, especially with respect to instrumentation and techniques that produce high-resolution data about the molecular constituents of living cells (DNA, mRNA, proteins, and metabolites) that are used as microbial signatures/fingerprints. Both bioinformatics and computational biology have grown over the last 20 years, and diverse database systems and analytical tools have been developed and deployed. Some public domain resources, such as GenBank, have become very important resources of research on a global scale. Effective responses to natural, accidental, or intentional outbreaks of infectious diseases in humans, livestock, and agricultural crops, will require that the information be easily accessed in realtime or near real-time. Flexible, decentralized, modular information system architectures, able to adapt to evolving requirements and available on the Internet, are needed.

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β-Glucosidase genes differentially expressed during composting

Biotechnology for Biofuels ◽

10.1186/s13068-020-01813-w ◽

2020 ◽

Vol 13 (1) ◽

Author(s):

Xinyue Zhang ◽

Bo Ma ◽

Jiawen Liu ◽

Xiehui Chen ◽

Shanshan Li ◽

...

Keyword(s):

Microbial Communities ◽

Environmental Changes ◽

Cellulose Degradation ◽

Degradation Mechanism ◽

Degradation Process ◽

Global Scale ◽

Expression Of Genes ◽

Glucose Tolerant ◽

Cooling Phase ◽

And Function

Abstract Background Cellulose degradation by cellulase is brought about by complex communities of interacting microorganisms, which significantly contribute to the cycling of carbon on a global scale. β-Glucosidase (BGL) is the rate-limiting enzyme in the cellulose degradation process. Thus, analyzing the expression of genes involved in cellulose degradation and regulation of BGL gene expression during composting will improve the understanding of the cellulose degradation mechanism. Based on our previous research, we hypothesized that BGL-producing microbial communities differentially regulate the expression of glucose-tolerant BGL and non-glucose-tolerant BGL to adapt to the changes in cellulose degradation conditions. Results To confirm this hypothesis, the structure and function of functional microbial communities involved in cellulose degradation were investigated by metatranscriptomics and a DNA library search of the GH1 family of BGLs involved in natural and inoculated composting. Under normal conditions, the group of non-glucose-tolerant BGL genes exhibited higher sensitivity to regulation than the glucose-tolerant BGL genes, which was suppressed during the composting process. Compared with the expression of endoglucanase and exoglucanase, the functional microbial communities exhibited a different transcriptional regulation of BGL genes during the cooling phase of natural composting. BGL-producing microbial communities upregulated the expression of glucose-tolerant BGL under carbon catabolite repression due to the increased glucose concentration, whereas the expression of non-glucose-tolerant BGL was suppressed. Conclusion Our results support the hypothesis that the functional microbial communities use multiple strategies of varying effectiveness to regulate the expression of BGL genes to facilitate adaptation to environmental changes.

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WITHDRAWN: A Last Interglacial record of environmental changes from the Sulmona Basin (central Italy)

Palaeogeography Palaeoclimatology Palaeoecology ◽

10.1016/j.palaeo.2017.01.012 ◽

2017 ◽

Author(s):

Eleonora Regattieri ◽

Biagio Giaccio ◽

Sebastien Nomade ◽

Alexander Francke ◽

Hendrik Vogel ◽

...

Keyword(s):

Environmental Changes ◽

Central Italy ◽

Last Interglacial

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A Review of Earth Observation-Based Analyses for Major River Basins

Remote Sensing ◽

10.3390/rs11242951 ◽

2019 ◽

Vol 11 (24) ◽

pp. 2951 ◽

Cited By ~ 1

Author(s):

Soner Uereyen ◽

Claudia Kuenzer

Keyword(s):

Land Surface ◽

Spatial Databases ◽

Spatial Information ◽

Environmental Changes ◽

River Basins ◽

Global Scale ◽

Earth Observation ◽

Basin Scale ◽

The Status ◽

Major River

Regardless of political boundaries, river basins are a functional unit of the Earth’s land surface and provide an abundance of resources for the environment and humans. They supply livelihoods supported by the typical characteristics of large river basins, such as the provision of freshwater, irrigation water, and transport opportunities. At the same time, they are impacted i.e., by human-induced environmental changes, boundary conflicts, and upstream–downstream inequalities. In the framework of water resource management, monitoring of river basins is therefore of high importance, in particular for researchers, stake-holders and decision-makers. However, land surface and surface water properties of many major river basins remain largely unmonitored at basin scale. Several inventories exist, yet consistent spatial databases describing the status of major river basins at global scale are lacking. Here, Earth observation (EO) is a potential source of spatial information providing large-scale data on the status of land surface properties. This review provides a comprehensive overview of existing research articles analyzing major river basins primarily using EO. Furthermore, this review proposes to exploit EO data together with relevant open global-scale geodata to establish a database and to enable consistent spatial analyses and evaluate past and current states of major river basins.

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Threshold effects of hazard mitigation in coastal human–environmental systems

Earth Surface Dynamics ◽

10.5194/esurf-2-35-2014 ◽

2014 ◽

Vol 2 (1) ◽

pp. 35-45 ◽

Cited By ~ 9

Author(s):

E. D. Lazarus

Keyword(s):

Climate Change ◽

Human Activities ◽

Social Dynamics ◽

Environmental Changes ◽

Hazard Mitigation ◽

Nonlinear Effects ◽

Time Frame ◽

Global Scale ◽

Coupling Mechanism ◽

Environmental Systems

Abstract. Despite improved scientific insight into physical and social dynamics related to natural disasters, the financial cost of extreme events continues to rise. This paradox is particularly evident along developed coastlines, where future hazards are projected to intensify with consequences of climate change, and where the presence of valuable infrastructure exacerbates risk. By design, coastal hazard mitigation buffers human activities against the variability of natural phenomena such as storms. But hazard mitigation also sets up feedbacks between human and natural dynamics. This paper explores developed coastlines as exemplary coupled human–environmental systems in which hazard mitigation is the key coupling mechanism. Results from a simplified numerical model of an agent-managed seawall illustrate the nonlinear effects that economic and physical thresholds can impart into coastal human–environmental system dynamics. The scale of mitigation action affects the time frame over which human activities and natural hazards interact. By accelerating environmental changes observable in some settings over human timescales of years to decades, climate change may temporarily strengthen the coupling between human and environmental dynamics. However, climate change could ultimately result in weaker coupling at those human timescales as mitigation actions increasingly engage global-scale systems.

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Modelling the extinction of Steller's sea cow

Biology Letters ◽

10.1098/rsbl.2005.0415 ◽

2005 ◽

Vol 2 (1) ◽

pp. 94-97 ◽

Cited By ~ 14

Author(s):

S.T Turvey ◽

C.L Risley

Keyword(s):

Environmental Changes ◽

Historical Period ◽

Sea Otter ◽

Commander Islands ◽

Mammal Species ◽

Life History Data ◽

Extinction Event ◽

Sea Cow ◽

Bering Island ◽

Catastrophic Impact

Steller's sea cow, a giant sirenian discovered in 1741 and extinct by 1768, is one of the few megafaunal mammal species to have died out during the historical period. The species is traditionally considered to have been exterminated by ‘blitzkrieg’-style direct overharvesting for food, but it has also been proposed that its extinction resulted from a sea urchin population explosion triggered by extirpation of local sea otter populations that eliminated the shallow-water kelps on which sea cows fed. Hunting records from eighteenth century Russian expeditions to the Commander Islands, in conjunction with life-history data extrapolated from dugongs, permit modelling of sea cow extinction dynamics. Sea cows were massively and wastefully overexploited, being hunted at over seven times the sustainable limit, and suggesting that the initial Bering Island sea cow population must have been higher than suggested by previous researchers to allow the species to survive even until 1768. Environmental changes caused by sea otter declines are unlikely to have contributed to this extinction event. This indicates that megafaunal extinctions can be effected by small bands of hunters using pre-industrial technologies, and highlights the catastrophic impact of wastefulness when overexploiting resources mistakenly perceived as ‘infinite’.

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