Environmental History Research Articles

Scars on the Land: An Environmental History of Slavery in the American South, by David Silkenat

<i>Scars on the Land: An Environmental History of Slavery in the American South</i>, by David Silkenat

Primary and Secondary Geochemical Signals in the Chemical Composition of Exoskeleton of Corumbella werneri (Tamengo Formation, Corumbá Group, Brazil): A Pilot Study

The study of Neoproterozoic carbonate sequences is complicated due to several variables influencing the geochemical and mineralogical composition, compounded by the scarcity of environmental analogs. The Tamengo Formation in the Corumbá Group is one of the most extensively studied archives of the Neoproterozoic in South America and encompasses Ediacaran guide fossils of Corumbella werneri and Cloudina lucianoi. This research focused on a marl sample containing well-preserved bioclasts of exoskeletons of Corumbella werneri, which is one of the earliest biomineralizing organisms. By utilizing diverse techniques such as optical and SEM microscopy, QEMSCAN imaging, electron microprobe, in situ ICP-MS, and isotope analyses, this study reveals primary and secondary signals in the bioclastic exoskeletons and the matrix within. These findings shed light on the sedimentary environment and diagenetic history of the Tamengo Formation. It is revealed that Corumbella werneri likely inhabited calm conditions, just below the base of storm waves and above a sharp chemocline at the bottom. In addition, the presence of distinct hydrothermal signals in the composition of REEs indicates a potential magmatic event that occurred in the region after the deposition of the succession. This pilot study highlights that the history recorded in the Neoproterozoic rocks of the Tamengo Formation is complex, and thus more detailed studies integrating lithological, paleontological, and geochemical parameters are necessary to reach a correct interpretation of this sequence.

An overview of Upper Pleistocene coastal deposits on Mallorca island

This review paper delves into the geological history of Mallorca, focusing on the Middle to Late Pleistocene period and its impact on the landscape and climate of the island. The Quaternary, particularly, the Last Interglacial, represents a relatively short timeframe on the global chronological scale, yet it is notable for its climatic instability and complex alternation of glacial and interglacial phases, leading to fluctuations in sea levels. During the last interglacial, millennial-scale fluctuations, known as Dansgaard–Oeschger and Heinrich events, occurred. Aeolianites are thought to have formed during periods of sparse vegetation cover and abundant sediment availability from the sea bed or platform (Heinrich events), while colluvial deposits and paleosols are believed to represent periods of reduced sediment supply and enhanced pedogenesis (Dansgaard–Oeschger events). These different deposits reflect climatic shifts and sea-level changes, offering insights into the environmental history of the island. Fossil evidence, including Strombus bubonius (currently known as Thetystrombus lauts) or “Senegalese hosts,” reveals past warm climatic fluctuations, particularly during the Last Interglacial. Myotragus balearicus exemplifies evolutionary adaptation and isolation on the island, offering a unique perspective on its paleontological legacy. The integration of stratigraphic characteristics and literature research on Optically Stimulated Luminescence (OSL) dating techniques provides a comprehensive temporal framework, spanning from Marine Isotope Stage 6 (MIS 6) to Marine Isotope Stage 2 (MIS 2), enabling the precise dating of geological events and a stratigraphic correlation.

Microhabitat acclimatization alters sea anemone-algal symbiosis and thermal tolerance across the intertidal zone.

Contemporary symbioses in extreme environments can give an insight into mechanisms that stabilize species interactions during environmental change. The intertidal sea anemone, Anthopleura elegantissima, engages in a nutritional symbiosis with microalgae similar to tropical coral, but withstands more intense environmental fluctuations during tidal inundations. In this study, we compare baseline symbiotic traits and their sensitivity to thermal stress within and among anemone aggregations across the intertidal using a laboratory-based tank experiment to better understand how fixed genotypic and plastic environmental effects contribute to the successful maintenance of this symbiosis in extreme habitats. High intertidal anemones had lower baseline symbiont-to-host cell ratios under control conditions, but their symbionts had higher baseline photosynthetic efficiency compared to low intertidal anemone symbionts. Symbiont communities were identical across all samples, suggesting that shifts in symbiont density and photosynthetic performance could be an acclimatory mechanism to maintain symbiosis in different environments. Despite lower baseline symbiont-to-host cell ratios, high intertidal anemones maintained greater symbiont-to-host cell ratios under heat stress compared with low intertidal anemones, suggesting greater thermal tolerance of high intertidal holobionts. However, the thermal tolerance of clonal anemones acclimatized to different zones was not explained by tidal height alone, indicating additional environmental variables contribute to physiological differences. Host genotype significantly influenced anemone weight, but only explained a minor proportion of variation among symbiotic traits and their response to thermal stress, further implicating environmental history as the primary driver of holobiont tolerance. These results indicate that this symbiosis is highly plastic and may be able to acclimatize to climate change over ecological timescales, defying the convention that symbiotic organisms are more susceptible to environmental stress.

Cinematic Activism and Tasmania’s Lake Pedder: How Film Shaped Environmental History

Film has played a seminal role in Australian environmental history, as an instrument of advocacy to shape political disputes and government actions. Such cinematic activism originated in the 1960s with the dispute over the damming of Tasmania’s iconic Lake Pedder. Here, documentary filmmaking was used by the protagonists to influence public opinion and convey rival views of the remote wilderness lake. For conservationists, film helped build an emotional connection and sense of place, whilst for pro-dam proponents, film helped curate an ideology of economic progress. The protagonists’ mutually reinforcing tactics, especially the intermediary role of the Tasmanian Department of Film Production, combined with the outstanding beauty of Lake Pedder, drove the turn to cinematic activism. Understanding how these films were produced and screened is also important to appreciating their significance for cinematic activism.

Tracing Holocene temperatures and human impact in a Greenlandic Lake: Novel insights from hyperspectral imaging and lipid biomarkers

Global warming particularly impacts terrestrial and aquatic ecosystems in the Arctic. To constrain the sensitivity of Arctic lakes and make meaningful predictions about future change under global warming, we need to examine their response to previous warm phases. Lake sediments from Greenland's deglaciated area offer valuable archives to investigate past climate variability and associated lake changes.Here, we applied hyperspectral imaging and lipid biomarker thermometry to a Holocene-length sediment record from Lake 578 in the Eastern Settlement of the Norse (61.08° N, 45.62° W; ∼155 m a.s.l) to investigate local temperature, productivity, and anoxia histories. We calibrated branched glycerol dialkyl glycerol tetraethers (brGDGTs) with summer mean water temperatures (SMWT) using a previously published site-specific calibration and analyzed pigment fluxes based on hyperspectral imaging. Notably, the anoxia reconstructions were corroborated with two independent proxies (GDGT-0/Crenarchaeol and bacterio pheophytins). We investigated the lake's environmental history and identified periods of significant change by employing generalized additive models (GAMs).Our results reveal significant transitions in Lake 578 driven both by natural climate shifts and anthropogenic impacts. During the early Holocene, low SMWT and productivity coupled with high anoxia suggest strong seasonality and prolonged inverted thermal stratification, possibly enhanced by extended ice cover. The mid-Holocene showed higher SMWT and productivity along with low anoxia, indicating a dimictic lake system. The early Holocene temperature rise lagged that of to the Northern Hemisphere, but closely followed the Atlantic-Fennoscandian stack. The Holocene Thermal Maximum (7.5–4.5 cal ka BP) aligns with other regional reconstructions. After 3 cal ka BP, we observed a Neoglacial cooling characterized by increased anoxia and reduced temperatures due to enhanced stratification. At around 1.0 cal ka BP, Lake 578 saw a surge in productivity and anoxia, which we attribute to land use and lake damming by the Norse. Despite a post-Norse decline in productivity and disappearance of anoxia, the lake never reverted to its pre-Norse state, with modern sheep farming further intensifying productivity in recent decades. While early Holocene anoxia resulted from natural cold temperature stratification, anoxia during the Norse period was anthropogenically induced.This research underscores the value of integrating lipid biomarkers with hyperspectral imaging for detailed reconstructions of changes within Arctic lakes. It provides crucial insights for anticipating the ecologic and climatic resilience of Arctic lakes to ongoing global warming and anthropogenic influence.

From Man vs. Nature to Environment vs. Budget - The Shifting Battles in the History of Pollution and Toxicity in Hamilton Harbour

Hamilton Harbour is the principle port serving South Western Ontario and the Niagara Peninsula region with two of Canada’s largest steel manufacturers occupying the waterfront. As early as the 1860s fishery inspectors in Hamilton noted that fish tasted of coal, and that there were dead ducks and small animals that were coated in oil from refineries. In the 1950s the Hamilton Harbour was deemed unfit for recreational use and, even today, has yet to be delisted from the International Joint Commission’s Area of Concerns designations list. Giglia’s article seeks to add to the growing scholarship on the environmental history of Ontario. She analyzes historical sources of pollution and shows how they have affected Hamilton Harbor’s ecology. Furthermore, Giglia weighs the efforts and effectiveness of specific groups in their attempt to delist the Hamilton Harbour from the Area of Concerns designation list.

‘Welcome to the Anthropocene’

The geological concept ‘the Anthropocene’ circulates widely outside Earth System Science – in museum communities, public culture, social sciences, and amongst social science and humanities scholars, artists, activists and public historians too. It is an evident idea for public historians today working with environmental history to engage with a concept that successfully and popularly bridges academic and public interests. This article discusses the concept of the Anthropocene within public environmental history’s historiography and brings in Dipesh Chakrabarty’s influential discussions from the academic field of history and theory about the non-synchronous temporalities geological time and historical time. The article categorizes public environmental history’s methodological approaches since the field emerged in the 1990s, revealing the important concepts being landscapes, human-nature interactions, climate change, sustainability and the Anthropocene. It concludes that the Anthropocene is a concept that can further develop public environmental history but that it also a paradox to the field potentially affecting a core idea in public history – relationships to publics. This has to do with temporal implications of the concept: it squeezes the temporality of memory important to public history and humans out of view; it imposes an extremely slow and long chronological time that is unfamiliar if not foreign to ordinary people to perceive of; it carries with it the idea about a future without humans and other species of today.

Long-term biotic homogenization in the East African Rift System over the last 6 million years of hominin evolution.

Eastern Africa preserves the most complete record of human evolution anywhere in the world but we have little knowledge of how long-term biogeographic dynamics in the region influenced hominin diversity and distributions. Here, we use spatial beta diversity analyses of mammal fossil records from the East African Rift System to reveal long-term biotic homogenization (increasing compositional similarity of faunas) over the last 6 Myr. Late Miocene and Pliocene faunas (~6-3 million years ago (Ma)) were largely composed of endemic species, with the shift towards biotic homogenization after ~3 Ma being driven by the loss of endemic species across functional groups and a growing number of shared grazing species. This major biogeographic transition closely tracks the regional expansion of grass-dominated ecosystems. Although grazers exhibit low beta diversity in open environments of the Early Pleistocene, the high beta diversity of Mio-Pliocene browsers and frugivores occurred in the context of extensive woody vegetation. We identify other key aspects of the Late Cenozoic biogeographic development of eastern Africa, their likely drivers and place the hominin fossil record in this context. Because hominins were undoubtedly influenced by many of the same factors as other eastern African mammals, this provides a new perspective on the links between environmental and human evolutionary histories.

Dating the middle and late Quaternary Caspian Sea-level fluctuations: First luminescence data from the coast of Turkmenistan

The Caspian region provides the basis of the stratigraphy and palaeogeography of the Pleistocene of Central Eurasia, and has been actively studied for more than 200 years. Many issues concerning the palaeogeographic history of the various basins of Caspian Quaternary remain unsolved, but the main problem centres on uncertainties in the chronology. Previous chronological studies have focused on a detailed description of the sedimentation history in the Lower Volga and Eastern Caucasus, ignoring a number of unique sites on the eastern Caspian coast, mainly due to inaccessibility. We obtained access to one of the most complete sections, western Cheleken, located on the Caspian coast of Turkmenistan. Within this sandy and generally lowland coast, the western part of the Cheleken peninsula forms a 10 km wide cliff opening a unique series of Middle Pleistocene - Holocene sediments which record in detail the history of Caspian transgressions and regressions. Stratigraphical, geomorphological and palaeontological studies of the section were supplemented with luminescence and radiocarbon dating. Analysis of Caspian molluscs and luminescence ages allowed the reconstruction of the sedimentary history of this region during one of the most important events of the Caspian Basin: the Early and Late Khazarian, Khvalynian and Novocaspian transgression/regression series. Luminescence dating of quartz and feldspar provided 12 OSL, IR50 and pIRIR290 ages, comparison of which showed that quartz grains were sufficiently bleached before deposition. Our chronology provides, for the first time, a deeper understanding of the sedimentation and environmental history in this region and the entire Caspian Sea. The Early Khazarian transgression occurred here at ∼220–200 ka (MIS 7). The Late Khazarian stage recorded in shallow-marine clays had relatively stable level ∼150–130 ka ago. In the second half of MIS 5 sea-level decreased and sedimentation was controlled by a large river, most probably the palaeo-Amu-Daria. The Early Khvalynian stage started at ∼27 ka and continued presumably until ∼14 ka.

Using machine learning to link climate, phylogeny and leaf area in eucalypts through a 50‐fold expansion of leaf trait datasets

Abstract Leaf area varies within and between species, and previous work has linked this variation to environment and evolutionary history. However, many previous studies fail to examine both these factors and often are data‐limited. To address this, our study developed a new workflow using machine learning to automate the extraction of leaf area from herbarium collections of Australian eucalypts (Eucalyptus, Angophora and Corymbia). This dataset included 136,599 measurements, expanding existing data on this taxon's leaf area by roughly 50‐fold. Our methods were validated using field standard metrics of accuracy, and comparisons to manual measurements both from the present study and existing datasets. With this dataset for the eucalypt clade, we observed positive relationships between leaf area and mean annual temperature and precipitation similar to those reported for the global flora. However, these relationships were not consistently observed within species, potentially due to gene flow suppressing local adaptation. When we examined these relationships at different phylogenetic levels, the slope of trait–climate associations within lineages converged towards the overall eucalypt slope at shallow phylogenetic scales (5–12 MY), suggesting that effects of gene flow relax just above the species level. The strengthening of trait–climate correlations at evolutionary scales just beyond the intraspecific level may represent a widespread phenomenon across various traits and taxa. Future studies can unveil these relationships with the larger sample sizes of new trait datasets generated through machine learning. Synthesis. Using machine learning, researchers are able to confirm current positive global relationships between leaf area and mean annual temperature and precipitation. Additionally, they were able to take this a step further and examine how it changes across time. Here they saw that at roughly 5–12 million years ago in the phylogenetic tree, the trait–climate slope begins to show significantly less variation. Overall, the study shows the potential of machine learning in ecology, with exciting new potential findings with its use.

The «Cultural Turn» in American Historiography of Environmental History from the 1980s to the Early 2000s: Causes and Consequences

The period since the 1970s has seen a «cultural turn» that affected many areas of historical research. Environmental history is no exception. It emerged in the United States five decades ago and was strongly influenced by intellectual history. However, in the 1990s, the focus of environmental historians gradually shifted towards «new cultural history». Although foreign historiography has repeatedly acknowledged this shift, the underlying reasons that prompted historians to pursue the new research path remain overlooked. This article seeks to bridge the «gap» in the historiography of human interactions with the natural world over time, an important branch of history. The results of a thorough analysis of the major works written by American historians between the 1970s and 2010s show that the «cultural turn» in the American historiography of environmental history was gradual and included two distinct stages. During the first stage, from the 1980s to the mid-1990s, historians explored the problems of environmental history from the perspectives of postcolonial and gender discourses. The second stage, from the mid-1990s to the present day, was marked by a rethinking of the concept of «wilderness», as well as an emphasis on a variety of previously unaddressed problems of environmental history.

The Environmental History of the Navazo Agroecosystem in Late Holocene Sand Bodies Along the Atlantic Coast of Andalusia, Spain

ABSTRACT Since the late Spanish Enlightenment, the agroecosystem of the Atlantic coast of Andalusia, through which coastal dune systems are cultivated via sunken gardens between sand berms, have attracted scholarly attention. The environmental history of these systems, known as Navazo, is the focus of this article. Through analysis of historical aerial photographs, we identify eight areas in which traditional Navazo land use was practiced. By studying landscape diversity and historical documentation we identify key aspects of the emergence and evolution of this agroecosystem. The results of this study indicate that Navazos originated through a combination of the natural properties offered by the region's coastal dune geomorphology, which was cultivated as vineyards since ancient times, as well as external cultural influences. Coinciding with the popularisation of potato consumption in the eighteenth century, earlier vineyards were, in some cases, completely replaced by Navazos. Due to transformations in traditional land use practices, created a contemporary version of the Navazo. The location and physical configuration of the Navazos, meanwhile, display strong similarities with archaeological remains of Plot-and-Berm agroecosystems from the southeastern Mediterranean dating from the Early Islamic period. This study presents evidence to better understand the function, cropping practices and irrigation of these systems. .

A visual construction history of the West Lothian shale bings

The West Lothian shale bings are large deposits of spent-shale rock in Scotland, created by the first industrial scale oil refineries which operated in the region from the mid-19th to the mid-20th century. Through its visual format, this gallery essay eschews formal investigative strategies to break with previous scholarship and interpret the bings as structures with their own construction history. Images of their current shape have been substituted for plans, photos and representations of them in development, to highlight the various logics and designs that converged within their construction. First-hand accounts from archived interviews have also been used to integrate the sensory and personal information that animated the bings as they were built. Social production is centred in this way to undermine an ideological narrative that sees waste as either aberrant corollary to intensive industry, or a neutral object without history. Analysing each image of the bings reveals intent, calculation and purpose which are pointedly incongruous with the view of waste as monolithic, accidental or unconscious. Such interpretations must be challenged because they obfuscate the necessarily profound impact of capital upon environmental history, as well as denuding ecology of its social aspects.

Conservation genomics of the wild pumpkin Cucurbita radicans in Central Mexico: The influence of a changing environment on the genetic diversity and differentiation of a rare species

The genetic diversity found in natural populations is the result of the evolutionary forces in response to historical and contemporary factors. The environmental characteristics and geological history of Mexico promoted the evolution and diversification of plant species, including wild relatives of crops such as the wild pumpkins (Cucurbita). Wild pumpkin species are found in a variety of habitats, evidencing their capability to adapt to different environments. Despite the potential value of wild Cucurbita as a genetic reservoir for crops, there is a lack of studies on their genetic diversity. Cucurbita radicans is an endangered species threatened by habitat destruction leading to low densities in small and isolated populations. Here, we analyze Genotype by Sequencing genomic data of the wild pumpkin C. radicans to evaluate the influence of factors like isolation, demographic history, and the environment shaping the amount and distribution of its genetic variation. We analyzed 91 individuals from 14 localities along its reported distribution. We obtained 5,107 SNPs and found medium-high levels of genetic diversity and genetic structure distributed in four main geographic areas with different environmental conditions. Moreover, we found signals of demographic growth related to historical climatic shifts. Outlier loci analysis showed significant association with the environment, principally with precipitation variables. Also, the outlier loci displayed differential changes in their frequencies in response to future global climate change scenarios. Using the results of genetic structure, outlier loci and multivariate analyses of the environmental conditions, we propose priority localities for conservation that encompass most of the genetic diversity of C. radicans.

Climate and environmental history of Laguna Polo, Santa Cruz, Southern Patagonia (49°S) since 1300 CE

Climate and environmental history of Laguna Polo, Santa Cruz, Southern Patagonia (49°S) since 1300 CE

Otoliths as chemical archives through ontogeny reveal distinct migratory strategies of Atlantic halibut within the Gulf of St. Lawrence

Abstract In marine fishes of commercial interest, defining habitat use and migration strategies through ontogeny can help better understand the structure and dynamics of harvested populations and guide their management. The present study relied on otolith chemistry to identify three contingents within the Atlantic halibut (Hippoglossus hippoglossus) stock in the Gulf of St. Lawrence (GSL). We differentiated two chemical signatures from otolith edges, one for shallow (&amp;lt;100 m) and another one for deep (&amp;gt;100 m) waters. By identifying transitions between the deep and shallow habitats, we found that most halibut display migrations from the deep waters to shallow waters during the first 3 years of life. After reaching maturity, most halibut distributing in northern regions of the GSL became full-time residents in deep areas of the GSL. In contrast, halibut found in summer on the shallow plateau of the southern GSL displayed migrating behaviour between shallow (summer) and deep (winter) waters throughout their lives, either on an annual or irregular basis. Overall, our results demonstrate that otolith chemical signatures serve as natural markers of geographically distinct marine environments, facilitating the identification and reconstruction of environmental histories of long-lived marine fishes.

Retrospective assessment of mine impacts: a case study using palaeoecology, aerial photography and maps from North Stradbroke Island (Minjerribah), Australia

ABSTRACT Mining is an environmentally destructive human activity. Consequently, community expectations and legislation require minimisation of impacts and rehabilitation once mining ceases. Rehabilitation standards now include restoration of structural and functional attributes of pre-disturbed landscapes. However, insufficient baseline data before, and during, mining often makes it difficult to assess impacts and develop rehabilitation objectives. Techniques that retrospectively document the pre-impact condition and environmental history of wetlands affected by mines can provide this information. We demonstrate how this can be achieved using data from palaeoecology and remote sensing, to understand mine impact on Fishermans Wetland, North Stradbroke Island (Minjerribah), by inferring its environmental history from formation to present. Fishermans Wetland is a small, clear, open water, wetland with extensive macrophyte growth. A lack of information about the wetland’s pre-mine condition created uncertainty about the effects of upstream sand mining. Contrary to local community concerns that Fishermans Wetland was ancient and hydrologically modified by mining, it only formed in the 1950s. Moreover, changes to site hydrology predated mining. Consequently, ongoing supplementation of water is unnecessary for maintaining the wetland’s ecological character. Similar techniques could be used elsewhere where mine impacts are poorly understood or contested.

Wide-Temperature Characteristics of Additively PBF-LB/M Processed Material Ti6Al4V

Titanium-based alloys are a widely applicable engineering material with high strength, low weight, non-magnetic, and corrosion resistance. At the same time, resistance to low temperatures is declared, which offers the material’s applicability for, e.g., aircraft or ship technology. Additive technologies are part of the industrial spectrum of material processing, especially the Laser Powder Bed Fusion of Metals method for metal alloys, which creates a layered structure of the resulting body. The topology of the internal structure, in relation to the temperature history of the functional environment, influences thermal expansion and the associated functional characteristics. Knowledge of the thermal expansion of printed strength and non-strength functional components and accessories is essential for future applications, especially in environments with high repeatable temperature changes, such as the aerospace industry. This paper presents the results of testing the expansion, mechanical, microstructural, and mineralogical characteristics of Ti6Al4V over the temperature range of −70 to 60 °C using a combination of instrumental techniques such as X-ray diffraction and nanoindentation. It was found that the topological orientations of the printed samples directly influenced the tested properties, e.g., the coefficient of thermal expansion in the direction perpendicular to the printed layers showed approximately 12% lower value compared to the other directions. Due to the progression of the application of the manufacturing method and its applicability within selected industries, the research provides results in a new area, which is supported by the relevant research.

The Undiagnosed Diseases Network: Characteristics of solvable applicants and diagnostic suggestions for nonaccepted ones

PurposeCan certain characteristics identify as solvable some undiagnosed patients who seek extensive evaluation and thorough record review, such as by the Undiagnosed Diseases Network (UDN)? MethodsThe UDN is a national research resource to solve medical mysteries through team science. Applicants provide informed consent to access to their medical records. After review, expert panels assess if applicants meet inclusion and exclusion criteria to select participants. When not accepting applicants, UDN experts may offer suggestions for diagnostic efforts. Using minimal information from initial applications, we compare features in applicants who are not accepted with those who are accepted and either solved or still not solved by the UDN. The diagnostic suggestions offered to nonaccepted applicants and their clinicians were tallied. ResultsNonaccepted applicants were more often female, older at first symptoms and application, and longer in review compared with accepted applicants. The accepted and successfully diagnosed applicants were younger, shorter in review time, more often non-White, of Hispanic ethnicity, and presenting with nervous system features. Half of nonaccepted applicants were given suggestions for further local diagnostic evaluation. A few seemed to have 2 major diagnoses or a provocative environmental exposure history. ConclusionComprehensive UDN record review generates possibly helpful advice.