Browsing by Subject "Anthropocene"
- Results Per Page
- Sort Options
Item Open Access A formal Anthropocene is compatible with but distinct from its diachronous anthropogenic counterparts: a response to W.F. Ruddiman’s ‘three flaws in defining a formal Anthropocene’(Progress in Physical Geography, 2019-06-01) Zalasiewicz, J; Waters, CN; Head, MJ; Poirier, C; Summerhayes, CP; Leinfelder, R; Grinevald, J; Steffen, W; Syvitski, J; Haff, P; McNeill, JR; Wagreich, M; Fairchild, IJ; Richter, DD; Vidas, D; Williams, M; Barnosky, AD; Cearreta, A© The Author(s) 2019. We analyse the ‘three flaws’ to potentially defining a formal Anthropocene geological time unit as advanced by Ruddiman (2018). (1) We recognize a long record of pre-industrial human impacts, but note that these increased in relative magnitude slowly and were strongly time-transgressive by comparison with the extraordinarily rapid, novel and near-globally synchronous changes of post-industrial time. (2) The rules of stratigraphic nomenclature do not ‘reject’ pre-industrial anthropogenic signals – these have long been a key characteristic and distinguishing feature of the Holocene. (3) In contrast to the contention that classical chronostratigraphy is now widely ignored by scientists, it remains vital and widely used in unambiguously defining geological time units and is an indispensable part of the Earth sciences. A mounting body of evidence indicates that the Anthropocene, considered as a precisely defined geological time unit that begins in the mid-20th century, is sharply distinct from the Holocene.Item Open Access Applying machine learning to investigate long-term insect-plant interactions preserved on digitized herbarium specimens.(Applications in plant sciences, 2020-06) Meineke, Emily K; Tomasi, Carlo; Yuan, Song; Pryer, Kathleen MPremise:Despite the economic significance of insect damage to plants (i.e., herbivory), long-term data documenting changes in herbivory are limited. Millions of pressed plant specimens are now available online and can be used to collect big data on plant-insect interactions during the Anthropocene. Methods:We initiated development of machine learning methods to automate extraction of herbivory data from herbarium specimens by training an insect damage detector and a damage type classifier on two distantly related plant species (Quercus bicolor and Onoclea sensibilis). We experimented with (1) classifying six types of herbivory and two control categories of undamaged leaf, and (2) detecting two of the damage categories for which several hundred annotations were available. Results:Damage detection results were mixed, with a mean average precision of 45% in the simultaneous detection and classification of two types of damage. However, damage classification on hand-drawn boxes identified the correct type of herbivory 81.5% of the time in eight categories. The damage classifier was accurate for categories with 100 or more test samples. Discussion:These tools are a promising first step for the automation of herbivory data collection. We describe ongoing efforts to increase the accuracy of these models, allowing researchers to extract similar data and apply them to biological hypotheses.Item Open Access Digital Environmental Metabolisms: An Ecocritical Project of the Digital Environmental Humanities(2017) Gould, Amanda StarlingBy combining literary, ecocritical, and media techniques with a mindfulness of the environment, “Digital Environmental Metabolisms: An Ecocritical Project of the Digital Environmental Humanities” contributes to the urgent task of re-orienting media theory toward environmental concerns. It is informed by the premise that, in our present Anthropocenic age defined by humans acting as a geophysical force, human bodies, cultural technologies, and the earth are intersecting material practices. I argue this intersectionality is neither cyborgian nor posthuman, as some media scholars insist, but is something far more natural: it is a metabolic relationship wherein each system is inherently implicated in the perpetuation of the others. Through a series of chapters that dispense with standard maps of cyberspace and the social network replacing them with a digital geography of wires, workers, warehouses, and waste, this project shifts the media theoretical focus from one grounded in computation to one fully rooted in the earth. Unlike others, like those mentioned here within, who are contributing to what may be called an emerging environmental media studies, I offer several practical and theoretical interventions, including Permaculture and Ecocritical Digital Humanities, that are capable of moving us toward more sustainable digital practice and a more robust Anthropocene Humanities.
Item Open Access Hydrologic Functioning of Low-Relief, Deep Soil Watersheds and Hydrologic Legacies of Intensive Agriculture in the Calhoun Critical Zone Observatory, South Carolina, USA(2020) Mallard, John McDevittWatersheds are complex, three dimensional structures that partition water between the components of the water balance and multiple storage pools within the watershed. This central function, however, remains poorly understood in a broadly transferable way despite decades of research. Perhaps one reason for this is the disciplinary bias towards studying pristine, mountainous watersheds with steep terrain and shallow soil. Although the relative simplicity of such systems has made them ideal hydrologic laboratories, understanding how watersheds function globally will require the incorporation of new types of landscapes into the studies of hillslope and watershed hydrology.
The Southern Piedmont region of the United States is situated between the Appalachian mountains and Atlantic coastal plains and stretches from Alabama to Maryland. It’s generally rolling terrain if underlain by deeply weathered and highly stratified soil characterized by relatively shallow argillic Bt horizons while weathered saprolite can extend tens of meters deep. Although it is a low-relief landscape, headwaters are often highly dissected with steep narrow valleys containing temporary streams surrounded by diverse topography. The region represents an ideal opportunity to incorporate more diverse landscapes into our studies of watershed hydrology.
As part of the NSF funded Calhoun Critical Zone Observatory, we intensively instrumented a 6.9 ha headwater (watershed 4, WS4), along with other targeted sensor locations including discharge in the 322 ha watershed that contains it (Holcombe’s Branch, HLCM), a nearby meteorological station, a deep groundwater well on a relatively flat interfluve, and a small network of wells in the buried floodplain. Sensors were continuously monitored for over 3 years while logging at 5 minute intervals. This sensor network allowed us to quantify the timing and magnitude of runoff, precipitation, deep and shallow groundwater levels distributed across a watershed, and soil moisture at multiple depths and hillslope positions. By doing so we were able to 1) describe the interactions between water balance components in WS4, 2) compare these watershed-scale measurements to internal hydrologic dynamics to determine what parts of the watershed are responsible for distinct watershed functions, and 3) explore how headwaters connect to higher order streams.
Using the monthly water balance in WS4, we calculated changes in integrated watershed storage and then derived a cumulative monthly storage time series from its running integral. We found that storage changes within the year by hundreds of millimeters (~25% of annual precipitation) in conjunction with seasonal peaks in evapotranspiration. Additionally, of all the potential variables that correlated to runoff magnitudes at the watershed scale, we found storage to be the best, particularly above a threshold value which remained remarkably consistent across all three years even with substantial differences in precipitation.
However, despite the storage threshold dependence of runoff, when we calculated daily storage we found that while runoff increased primarily in response to major precipitation events and then decreased again shortly thereafter, storage primarily wet up once from its low point at the end of the growing season and then drained starting at the growing season and continuing through the summer. Similarly, individual measurements of internal watershed hydrology like soil moisture or water table level displayed either seasonal or event-scale changes. We determined that measurements taken at watershed positions with more convergent hillslopes, or farther from the watershed divide, or installed deeper in the soil are more likely to display seasonal changes, and vice versa for event-scale changes. These three gradients are essentially proxies for vertical, lateral, and longitudinal distances, and so it appeared that the underlying gradient being measured was actually contributing volume. We determined the functions of different landscape components based on this analysis, and came to understand that storage-linked sites wet up first and then stay consistently so, making conditions for runoff. Subsequently, when runoff-linked sites wet-up, they mobilize significant runoff fluxes either by hydraulic displacement, or interflow, or a transmissivity feedback, or likely some combination of them all. During these times a substantial portion of the watershed is connected before drying down again with the exception of more storage-linked locations.
The result of this threshold setting followed by large runoff events is extremely flashy outputs from WS4. In contrast, we found HLCM to be far less flashy and relatively less sensitive to year to year fluctuations in precipitation. Further, we observed that except in the most extreme storms, surface flow from WS4 across the former floodplain in between it and HLCM always fully infiltrates into the sandy, legacy sediments deposited along the entire former floodplain. These sediments are the legacy of centuries of intensive and poorly managed agriculture across the Southern Piedmont. Wells in these sediments revealed a highly dynamic water table that was very responsive to outflow from WS4. A simple geometric simplification of the shape of these sediments and an estimate of their porosity revealed that these sediments had ~900 m3 of available storage space, space that was constantly filling and draining. Interestingly, that available storage volume level was sufficient to absorb discharge from WS4 on 97% of the days we measured. Through most of WS4 flow states, this storage served to buffer HLCM from flashier runoff coming from WS4, and then subsequently releasing it much more slowly and drawn out as shallow subsurfaceflow. However, when it reached volumes within 15% of maximum, usually in conjunction with large fluxes coming from WS4, runoff in HLCM reacted closely with WS4. So the storage volume in legacy sediments serves as an effective buffer from flashy upstream hydrology, but when the reach or approach saturation they become effective at transmitting surface flow, likely via saturation excess. Although we observed this phenomenon in only one alluvial fan, we have reason to think that such features are quite common locally and regionally, and represent a heretofore underappreciated legacy of historic agriculture.
Taken together, these findings describe a hydrologic system that is much more dynamic than its abundant rainfall and surface water resources would suggest. Further, they indicate that even a century or more after agricultural land abandonment and forest regrowth, legacies of the 18th and 19th century remain in the landforms and soils of the region. We feel that these findings are strong support for continued and expanded hydrologic study at the CCZO and in the Southern Piedmont in general.
Item Open Access Low-intensity logging and hunting have long-term effects on seed dispersal but not fecundity in Afrotropical forests.(AoB PLANTS, 2019-02) Nuñez, Chase L; Clark, James S; Clark, Connie J; Poulsen, John RHunting and logging, ubiquitous human disturbances in tropical forests, have the potential to alter the ecological processes that govern population recruitment and community composition. Hunting-induced declines in populations of seed-dispersing animals are expected to reduce dispersal of the tree species that rely on them, resulting in potentially greater distance- and density-dependent mortality. At the same time, selective logging may alter competitive interactions among tree species, releasing remaining trees from light, nutrient or space limitations. Taken together, these disturbances may alter the community composition of tropical forests, with implications for carbon storage, biodiversity conservation and ecosystem function. To evaluate the effects of hunting and logging on tree fecundity and seed dispersal, we use 3 years of seed rain data from a large-scale observational experiment in previously logged, hunted and protected forests in northern Republic of Congo (Brazzaville). We find that low-intensity logging had a meaningful long-term effect on species-specific seed dispersal distances, though the direction and magnitude varied and was not congruent within dispersal vector. Tree fecundity increased with tree diameter, but did not differ appreciably across disturbance regimes. The species-specific dispersal responses to logging in this study point towards the long-lasting toll of disturbance on ecological function and highlight the necessity of conserving intact forest.Item Open Access Maintenance Works: The Aesthetics and Politics of Collective Support.(2021) Symuleski, Max J.Maintenance Works: The Aesthetics and Politics of Collective Support investigates the cultural visibility and value of maintenance labor through a critical examination of American visual and material culture, post-1969. Starting from the visual and performance practice of self-proclaimed “maintenance artist” Mierle Laderman Ukeles and her Manifesto For Maintenance Art 1969!, I develop a conceptual definition of maintenance as sustaining activity that occurs across scales, from the intimate labor of caring for bodies, to the collective, macro-scale problems of sustaining infrastructures and environments. I argue that, with the gesture of assigning her own and others’ maintenance labor the status of “artwork”, Ukeles prompts a critical re-valuation of the visibility and social and economic value of maintenance that resonates with a host of historical and contemporary discourses on the gendered and stratified distribution of material and social reproduction, including Marxist-feminist approaches to care work, critiques of innovation discourse in science and technology studies, and concern with issues of social and economic precarity in recent cultural criticism and critical theory. At the center of both Ukeles’ project and these discussions lie important questions about the status, conditions, and social distribution of care and support: Who is doing it? How does it get done? How does it feel to maintain or be maintained? What happens when practices and structures of social and material support fail, whether through immediate crisis or prolonged neglect? How do those affected find ways of maintaining otherwise? Each chapter of Maintenance Works approaches these questions by examining the visual and material culture around what I define as late 20th-century “crises of maintenance”: shifting economies of care and support, global environmental destruction, and institutionalized abandonment and neglect. The cultural objects I discuss span decades and genres, including land and environmental art, feminist and queer performance, and social practice. Through these material case studies I add important theoretical and cultural foundation to contemporary discussions on care, precarity, and sustainability across disciplines from queer and feminist theory to eco-critical humanities, to science and technology studies, and center the production and reception of artwork as sites for critical inquiry and knowledge production.
Item Open Access Making the case for a formal Anthropocene Epoch: An analysis of ongoing critiques(Newsletters on Stratigraphy, 2017-01-01) Zalasiewicz, J; Waters, CN; Wolfe, AP; Barnosky, AD; Cearreta, A; Edgeworth, M; Ellis, EC; Fairchild, IJ; Gradstein, FM; Grinevald, J; Haff, P; Head, MJ; do Sul, JAI; Jeandel, C; Leinfelder, R; McNeill, JR; Oreskes, N; Poirier, C; Revkin, A; Richter, DDB; Steffen, W; Summerhayes, C; Syvitski, JPM; Vidas, D; Wagreich, M; Wing, S; Williams, M© 2017 The Authors. A range of published arguments against formalizing the Anthropocene as a geological time unit have variously suggested that it is a misleading term of non-stratigraphic origin and usage, is based on insignificant temporal and material stratigraphic content unlike that used to define older geological time units, is focused on observation of human history or speculation about the future rather than geologically significant events, and is driven more by politics than science. In response, we contend that the Anthropocene is a functional term that has firm geological grounding in a well-characterized stratigraphic record. This record, although often lithologically thin, is laterally extensive, rich in detail and already reflects substantial elapsed (and in part irreversible) change to the Earth System that is comparable to or greater in magnitude than that of previous epoch-scale transitions. The Anthropocene differs from previously defined epochs in reflecting contemporary geological change, which in turn also leads to the term's use over a wide range of social and political discourse. Nevertheless, that use remains entirely distinct from its demonstrable stratigraphic underpinning. Here we respond to the arguments opposing the geological validity and utility of the Anthropocene, and submit that a strong case may be made for the Anthropocene to be treated as a formal chronostratigraphic unit and added to the Geological Time Scale.Item Open Access Marine resource management and conservation in the Anthropocene(Environmental Conservation, 2018-06-01) ASWANI, SHANKAR; BASURTO, XAVIER; FERSE, SEBASTIAN; GLASER, MARION; CAMPBELL, LISA; CINNER, JOSHUAE; DALTON, TRACEY; JENKINS, LEKELIAD; MILLER, MARCL; POLLNAC, RICHARD; VACCARO, ISMAEL; CHRISTIE, PATRICK© 2017 Foundation for Environmental Conservation. Because the Anthropocene by definition is an epoch during which environmental change is largely anthropogenic and driven by social, economic, psychological and political forces, environmental social scientists can effectively analyse human behaviour and knowledge systems in this context. In this subject review, we summarize key ways in which the environmental social sciences can better inform fisheries management policy and practice and marine conservation in the Anthropocene. We argue that environmental social scientists are particularly well positioned to synergize research to fill the gaps between: (1) local behaviours/needs/worldviews and marine resource management and biological conservation concerns; and (2) large-scale drivers of planetary environmental change (globalization, affluence, technological change, etc.) and local cognitive, socioeconomic, cultural and historical processes that shape human behaviour in the marine environment. To illustrate this, we synthesize the roles of various environmental social science disciplines in better understanding the interaction between humans and tropical marine ecosystems in developing nations where issues arising from human-coastal interactions are particularly pronounced. We focus on: (1) the application of the environmental social sciences in marine resource management and conservation; (2) the development of 'new' socially equitable marine conservation; (3) repopulating the seascape; (4) incorporating multi-scale dynamics of marine social-ecological systems; and (5) envisioning the future of marine resource management and conservation for producing policies and projects for comprehensive and successful resource management and conservation in the Anthropocene.Item Open Access Oceans as the Paradigm of History(Theory, Culture and Society, 2021-01-01) Duara, PThe temporality of historical flows can be understood through the paradigm of oceanic circulations of water. Historical processes are not linear and tunneled but circulatory and global, like oceanic currents. The argument of distributed agency deriving from the ‘ontological turn’ dovetails with the oceanic paradigm of circulatory histories. The latter allows us to grasp modes of both natural and historical inter-temporal communication through the medium of the natural and built environment. Yet the inclination in these new studies to deny any particular privilege to human will or design risks neglecting the changing role of human agency. Analytically I distinguish historiographical time from historical time. Historiographical time may be seen as the purposive capture of historical processes for various goals whereas historical time is more continuous with natural flows. More than origins and causes, the paradigm emphasizes the ramifying con-sequences of purposive actions. The gap in our understanding of the two temporalities has had a devastating impact on the planet.Item Open Access Oceans, Gardens, and Jungles: World Politics and the Planet(Duke Global Working Paper Series, 2022-04-27) Duara, PrasenjitItem Open Access Persistent anthropogenic legacies structure depth dependence of regenerating rooting systems and their functions(Biogeochemistry, 2020-02-01) Hauser, E; Richter, DD; Markewitz, D; Brecheisen, Z; Billings, SA© 2020, Springer Nature Switzerland AG. Biotically-mediated weathering helps to shape Earth’s surface. For example, plants expend carbon (C) to mobilize nutrients in forms whose relative abundances vary with depth. It thus is likely that trees’ nutrient acquisition strategies—their investment in rooting systems and exudates—may function differently following disturbance-induced changes in depth of rooting zones and soil nutrient stocks. These changes may persist across centuries. We test the hypothesis that plant C allocation for nutrient acquisition is depth dependent as a function of rooting system development and relative abundances of organic vs. mineral nutrient stocks. We further posit that patterns of belowground C allocation to nutrient acquisition reveal anthropogenic signatures through many decades of forest regeneration. To test this idea, we examined fine root abundances and rooting system C in organic acid exudates and exo-enzymes in tandem with depth distributions of organically- and mineral-bound P stocks. Our design permitted us to estimate C tradeoffs between organic vs. mineral nutrient benefits in paired forests with many similar aboveground traits but different ages: post-agricultural mixed-pine forests and older reference hardwoods. Fine roots were more abundant throughout the upper 2 m in reference forest soils than in regenerating stands. Rooting systems in all forests exhibited depth-dependent C allocations to nutrient acquisition reflecting relative abundances of organic vs. mineral bound P stocks. Further, organic vs. mineral stocks underwent redistribution with historic land use, producing distinct ecosystem nutritional economies. In reference forests, rooting systems are allocating C to relatively deep fine roots and low-C exudation strategies that can increase mobility of mineral-bound P stocks. Regenerating forests exhibit relatively shallower fine root distributions and more diverse exudation strategies reflecting more variable nutrient stocks. We observed these disparities in rooting systems’ depth and nutritional mechanisms even though the regenerating forests have attained aboveground biomass stocks similar to those in reference hardwood forests. These distinctions offer plausible belowground mechanisms for observations of continued C sink strength in relatively old forests, and have implications for soil C fates and soil development on timescales relevant to human lifetimes. As such, depth-dependent nutrient returns on plant C investments represent a subtle but consequential signal of the Anthropocene.Item Open Access Speculative Biologies: New Directions in Art in the Age of the Anthropocene(2016) Yoldas, PinarThis dissertation is an attempt to explain art in the 21st century by an artist/researcher. It is a theoretical writing on art informed by current discourses that influence art such as science and technology. There are two goals of this project. The first one is to understand art’s cultural role in the age of the anthropocene. What is the anthropocene? How does art’s role in society change in this particular geological epoch (following Crutzen’s definition), compared to for instance Holocene? This brings us to the second goal of my project. To better understand art’s role in society, can we benefit from a theory of art, that could present an insight on the dynamics within an artistic experience? What are the current tools and tendencies that can help form such a theory of art? Which fields can contribute to such an understanding?
As an instance of artistic research practice which involves both academic research and art practice, I will be using art projects as case studies to reach these goals. Case studies will consist of my own projects as well as projects by other artists who had been working on similar topics such as Edward Burtynsky, Chris Jordan, Louis Bec, Trevor Paglen, Patricia Piccinini and Lynn Hershmann to name a few. From Timothy Morton to Mackenzie Wark to Donna Haraway cultural theorists of our time, highlight the fact that there is a need for a cultural theory that can attend to what we might call the anthropocene. What is the contribution of art for such a theory? Or can art be instrumental in building a cultural theory at all? My dissertation offers a multi-disciplinary argument for the need to address such questions . Starting from art’s roots in biology and extending to what we might call our biological imagination, the dissertation focuses on art’s connection to biology to initiate a formula for art in the age of the anthropocene.
Item Open Access Woman, Nature, and Observer in Tess of the D'Urbervilles and To the Lighthouse: An Ecofeminist Approach(2017-09-19) George, ElizabethThis thesis discusses narration as a tool that mediates the portrayal of women and nature by subjecting both to the perspective of an observer. Realist fiction provides us with material to study this phenomenon in depth because of its intention to reflect reality. Accordingly, Miss George argues that there are ecological stakes in narrative technique because the way we narrate fictional human relationships to nature reflects and influences actual human relationships with the environment. In the late nineteenth and early twentieth centuries, massive shifts were occurring in those relationships. This period also saw the end of one literary tradition (Victorian realism) and the start of another (modernist experimentalism). Miss George believes that the two are related, that transformations in narration techniques coincided with a consciousness of planetary change.