An annually laminated succession in Crawford Lake, Ontario, Canada is proposed as the Global boundary Stratotype Section and Point (GSSP) for the Anthropocene as a series/epoch with a base dated at 1950 CE. Varve couplets of organic matter capped by calcite precipitated each summer in alkaline surface waters reflect environmental change at global to local scales. Spheroidal carbonaceous particles and nitrogen isotopes record an increase in fossil fuel combustion in the early 1950s, coinciding with fallout from nuclear and thermonuclear testing—239+240Pu and 14C:12C, the latter more than compensating for the effects of old carbon in this dolomitic basin. Rapid industrial expansion in the North American Great Lakes region led to enhanced leaching of terrigenous elements by acid precipitation during the Great Acceleration, and calcite precipitation was reduced, producing thin calcite laminae around the GSSP that is marked by a sharp decline in elm pollen (Dutch Elm disease). The lack of bioturbation in well-oxygenated bottom waters, supported by the absence of fossil pigments from obligately anaerobic purple sulfur bacteria, is attributed to elevated salinities and high alkalinity below the chemocline. This aerobic depositional environment, unusual in a meromictic lake, inhibits the mobilization of 239Pu, the proposed primary stratigraphic guide for the Anthropocene.
We examine three distinctive biostratigraphic signatures of humans associated with hunting and gathering, landscape domestication and globalization. All three signatures have significant fossil records of regional importance that can be correlated inter‐regionally and help describe the developing pattern of human expansion and appropriation of resources. While none have individual first or last appearances that provide a globally isochronous marker, all three signatures overlap stratigraphically, in that they are part of a continuum of change, with complex regional patterns. Here we show that during the later stages of globalization, late nineteenth to twentieth century records of species translocations can be used to build an interconnected web of palaeontological correlation with decadal or sub‐decadal precision that dovetails with other stratigraphic markers for the Anthropocene. This palaeontological web is also a proxy for accelerating species extinction and of a state shift in the biosphere in the twentieth century.
The earliest eukaryotes recorded in continental environments are non-pollen palynomorphs (NPP) in Mesoproterozoic strata, and NPP provide our best insights into lacustrine ecosystems through the Paleogene. They have been underexploited in studies of younger lake sediments, either ignored or only qualitatively observed, because many NPP are destroyed by standard processing techniques for pollen and embryophyte spores. The palaeoenvironmental potential of palynomorphs, with representatives from all eukaryotic kingdoms as well as cyanobacteria and from all trophic levels in various lacustrine environments, has been recognized by a few Quaternary palynologists in the past few decades. NPP have proven particularly valuable in archaeological and environmental monitoring studies of human impact on freshwater ecosystems, with spores of some fungi and eggs/ egg cases of some flatworms and roundworms associated with feces of humans and livestock, and the acid-resistant remains of various life stages of cyanobacteria, algae, and their aquatic consumers responding to increased turbidity and nutrient influx associated with permanent human settlements, particularly those associated with agricultural activity. Descriptions of NPP commonly encountered in Quaternary lake sediments and case studies illustrating applications to various research questions should encourage more palynologists that ‘Quaternary non-pollen palynomorphs' deserve our attention!’, to quote Prof. Bas van Geel, undisputed Father of NPP Research.Supplementary material at https://doi.org/10.6084/m9.figshare.c.5244661
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