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1.
Proc Natl Acad Sci U S A ; 121(41): e2313098121, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39312679

RESUMO

One of the remaining issues regarding the Anthropocene is the lack of stratigraphic evidence indicating when the cumulative human pressure from the early Holocene began to fundamentally change the Earth system. Herein, we compile anthropogenic fingerprints from various high-precision-dated proxy records for 137 global sites to determine the age of the unprecedented surge in these records over the last 7700 y. The cumulative number of fingerprints revealed an unprecedented surge in diverse anthropogenic fingerprints starting in 1952 ± 3 CE, corresponding to the onset of the Great Acceleration. Notably, the period from 1953 to 1958 CE saw a nearly simultaneous surge in fingerprints across all regions, including Antarctica, the Arctic, East Asia, Europe, North America, and Oceania. This synchronous upsurge reflects the moment when human impacts led to rapid transformations in various natural processes and cycles, with humans becoming a geological force capable of inscribing abundant and diverse anthropogenic fingerprints in global strata. Following this global fingerprint explosion, profound planetary-scale changes, including deviations from the established natural climatic conditions, begin. This unprecedented surge in anthropogenic signals worldwide suggests that human influences started to match many natural forces controlling the processes and cycles and overwhelm some of the functioning of the Earth system around 1952.


Assuntos
Efeitos Antropogênicos , Humanos , Geologia , Planeta Terra , Arquivos
2.
Biol Open ; 13(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38427427

RESUMO

The 53rd Ontario Ecology, Ethology, and Evolution Colloquium (OE3C 2023) took place at Western University (London, Canada) on 25-27 May 2023, attracting 160 participants. This Meeting Review aims not only to recapitulate what was discussed during the event, but also to provide a brief synthesis of how biologists can move forward. The event was organised and run by graduate students and postdoctoral researchers from the Department of Biology at Western University. With three international keynote speakers, seventy talks, and fifty poster presentations, the OE3C 2023 spanned a wide range of contemporary research in Ecology, Ethology, and Evolution ("the 3 E's"). The colloquium theme was "Surviving the Anthropocene: future steps for the 3 E's under pressing planetary issues", which was complemented by illustrations depicting the fauna and flora of the "Canadian Anthropocene". Participants discussed what biologists and researchers can do regarding future climate and environmental catastrophes. The meeting culminated in a panel discussion comprising three climate change specialists who examined topics such as the Anthropocene and the Great acceleration, the living planet index, and carbon bombs. Although not exhaustive, these topics served as a starting point for the necessary discussions about how biologists can contribute to the fight for the survival of life on Earth.


Assuntos
Mudança Climática , Etologia , Humanos , Canadá
3.
Anthropocene Rev ; 10(1): 146-176, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37255737

RESUMO

An annually laminated succession in Crawford Lake, Ontario, Canada is proposed for the Global boundary Stratotype Section and Point (GSSP) to define 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 early 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, highly unusual in a meromictic lake, inhibits the mobilization of Pu, the proposed primary stratigraphic guide for the Anthropocene.

4.
Sci Total Environ ; 703: 134926, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-31731148

RESUMO

Trace element concentrations in the youngest Holocene sedimentary archives, historical mining, and archaeological sites are reliable indicators for historical anthropogenic contamination. The Pleistocene-Holocene strata and the overlying archaeological sites of the Peshawar Basin, NW Pakistan provide sedimentary archives to explore historical anthropogenic controls on the distributions of trace elements. The basin with 2500 y of human civilization was sampled using archaeological trenches at Gor Khuttree and Hund, and six sections of youngest Pleistocene-Holocene strata along river banks. Geochemical analysis of high-resolution samples were conducted for both the lacustrine-floodplain sediments and archaeological sites. Results from various horizons of the archaeological sites provide signals for anthropogenic control on the distribution of As, Zn, Cu, Mo, Pb, Hg, Ag, and Au during the Meghalayan Stage of Holocene that gain progressive strength since the 18th century. The geochemical proxies negate direct mining of Cu-Pb and Zn in the area. The consistent, anthropogenic Ag and Au contribution to the system throughout the basin's archaeological history is a significant finding. When correlated against the anthropogenic mercury contamination, it appears that Hund was a major silver-gold panning site throughout its known history whereas Gor Khuttree was the major silver-gold processing center. The Peshawar Basin anthropogenic signals contribute to widespread European early Anthropocene signals at around 2000 BP related to the Greek and Roman mining. Signals during the Hindu Shahi period correlate well with the Medieval period mining and smelting peak signals observed in Europe and China. Hg, Ag, and Au concentrations in the area since the start of the 19th century CE correlates to the start of industrialisation. During the mid-20th century, these geochemical signals from the Gor Khuttree reflect anthropogenic contributions to the local system and correlate to the suggested base of a formalised Anthropocene.

5.
One Earth ; 2(4): 329-340, 2020 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-33501419

RESUMO

Despite the decades-long efforts of sustainability science and related policy and action programs, humanity has not gotten closer to global sustainability. With its focus on the natural sciences, sustainability science is not able to contribute sufficiently to the global transition to sustainability. This Perspective argues for transforming sustainability science into a transdisciplinary enterprise that can generate positive social and environmental change globally. In such transformation, the social sciences, humanities, and the arts can play an important role to address the complex problems of culture, institutions, and human behavior. To realize a truly integrated sustainability science, we need renewed research and public policies that reshape the research ecosystem of universities, funding agencies, science communications, policymaking, and decision making. Sustainability science must also engage with society and creatively employ all available sources of knowledge in favor of creating a sustainable Earth.

6.
Glob Environ Change ; 52: 131-140, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30679887

RESUMO

The size and structure of the socioeconomic metabolism are key for the planet's sustainability. In this article, we provide a consistent assessment of the development of material flows through the global economy in the period 1900-2015 using material flow accounting in combination with results from dynamic stock-flow modelling. Based on this approach, we can trace materials from extraction to their use, their accumulation in in-use stocks and finally to outflows of wastes and emissions and provide a comprehensive picture of the evolution of societies metabolism during global industrialization. This enables outlooks on inflows and outflows, which environmental policy makers require for pursuing strategies towards a more sustainable resource use. Over the whole time period, we observe a growth in global material extraction by a factor of 12 to 89 Gt/yr. A shift from materials for dissipative use to stock building materials resulted in a massive increase of in-use stocks of materials to 961 Gt in 2015. Since materials increasingly accumulate in stocks, outflows of wastes are growing at a slower pace than inputs. In 2015, outflows amounted to 58 Gt/yr, of which 35% were solid wastes and 25% emissions, the reminder being excrements, dissipative use and water vapor. Our results indicate a significant acceleration of global material flows since the beginning of the 21st century. We show that this acceleration, which took off in 2002, was not a short-term phenomenon but continues since more than a decade. Between 2002 and 2015, global material extraction increased by 53% in spite of the 2008 economic crisis. Based on detailed data on material stocks and flows and information on their long-term historic development, we make a rough estimate of what a global convergence of metabolic patterns at the current level in industrialized countries paired with a continuation of past efficiency gains might imply for global material demand. We find that in such a scenario until 2050 average global metabolic rates double to 22 t/cap/yr and material extraction increases to around 218 Gt/yr. Overall the analysis indicates a grand challenge calling for urgent action, fostering a continuous and considerable reduction of material flows to acceptable levels.

7.
NTM ; 24(3): 309-335, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27567637

RESUMO

In 2000, when atmospheric chemist Paul J. Crutzen and limnologist Eugene F. Stoermer proposed to introduce a new geological era, the Anthropocene, they could not have foreseen the remarkable career of the new term. Within a few years, the geological community began to investigate the scientific evidence for the concept and established the Anthropocene Working Group. While the Working Group has started to examine possible markers and periodizations of the new epoch, scholars from numerous other disciplines have taken up the Anthropocene as a cultural concept. In addition, the media have developed a deep interest in the Anthropocene's broader societal ramifications. The article sheds light on the controversial debate about the Anthropocene and discusses its inextricably linked dual careers, first as a geological term and second as a cultural term. Third, it argues that the debate about the "Age of Humans" is a timely opportunity both to rethink the nature-culture relation and to re-assess the narratives that historians of science, technology, and the environment have written until now. Specifically, it examines both the heuristic and analytical power of the concept. It discusses new histories, new ideas to understand historical change, and new temporalities shaped by scholars who have taken up the challenge of the Anthropocene as a cultural concept that has the ability to question established stories and narratives. Fourth, it ends by stressing the potential of the Anthropocene concept to blur established epistemological boundaries and to stimulate cross-disciplinary collaborations between the sciences and the humanities.

8.
Glob Chang Biol ; 22(1): 271-83, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26313740

RESUMO

Coherent timing of agricultural expansion, fertilizer application, atmospheric nutrient deposition, and accelerated global warming is expected to promote synchronous fertilization of regional surface waters and coherent development of algal blooms and lake eutrophication. While broad-scale cyanobacterial expansion is evident in global meta-analyses, little is known of whether lakes in discrete catchments within a common lake district also exhibit coherent water quality degradation through anthropogenic forcing. Consequently, the primary goal of this study was to determine whether agricultural development since ca. 1900, accelerated use of fertilizer since 1960, atmospheric deposition of reactive N, or regional climate warming has resulted in coherent patterns of eutrophication of surface waters in southern Alberta, Canada. Unexpectedly, analysis of sedimentary pigments as an index of changes in total algal abundance since ca. 1850 revealed that while total algal abundance (as ß-carotene, pheophytin a) increased in nine of 10 lakes over 150 years, the onset of eutrophication varied by a century and was asynchronous across basins. Similarly, analysis of temporal sequences with least-squares regression revealed that the relative abundance of cyanobacteria (echinenone) either decreased or did not change significantly in eight of the lakes since ca. 1850, whereas purple sulfur bacteria (as okenone) increased significantly in seven study sites. These patterns are consistent with the catchment filter hypothesis, which posits that lakes exhibit unique responses to common forcing associated with the influx of mass as water, nutrients, or particles.


Assuntos
Cianobactérias/crescimento & desenvolvimento , Eutrofização , Sedimentos Geológicos/química , Lagos/microbiologia , Pigmentos Biológicos/análise , Agricultura , Alberta , Mudança Climática , Monitoramento Ambiental , Eucariotos/crescimento & desenvolvimento , Fertilizantes , Água Doce/química , Água Doce/microbiologia , Lagos/química , Qualidade da Água
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