Mathematical modeling is a convenient way for characterization of complex ecosystems. This approach was applied to study the dynamics of zooplankton in Lake Sevan (Armenia) at different stages of anthropogenic eutrophication with the use of a novel method called discrete modeling of dynamical systems with feedback (DMDS). Simulation demonstrated that the application of this method helps in characterization of inter- and intra-component relationships in a natural ecosystem. This method describes all possible pairwise inter-component relationships like “plus–plus,” “minus–minus,” “plus–minus,” “plus–zero,” (...) “minus–zero,” and “zero–zero” that occur in most ecosystems. Based on the results, a working hypothesis was formulated. It was found that the sensitivity to weak external influence in zooplanktons was the greatest during the mid period of eutrophication in Lake Sevan, whereas in the final stages of eutrophication, an outbreak in the biomass production of cyanobacteria was evident. To support this approach, a weak external disturbance in the form of magnetic storm was used to see its effect on species Daphnia longispina sevanica. A statistically significant correlation between the frequency of magnetic storms and the number of this species was revealed and an increase in the number of toxic cyanobacteria species as a consequence of eutrophication. This paper, for the first time, suggests a DMDS method, to diagnose impact of anthropogenic eutrophication on environment. (shrink)

In this paper, we investigate the dynamics of autonomous and nonautonomous stochastic toxin-producing phytoplankton–zooplankton system. For the autonomous system, we establish the sufficient conditions for the existence of the globally positive solution as well as the solution of population extinction and persistence in the mean. Furthermore, by constructing some suitable Lyapunov functions, we also prove that there exists a single stationary distribution which is ergodic, what is more important is that Lyapunov function does not depend on existence and stability (...) of equilibrium. For the nonautonomous periodic system, we prove that there exists at least one nontrivial positive periodic solution according to the theory of Khasminskii. Finally, some numerical simulations are introduced to illustrate our theoretical results. The results show that weaker white noise and/or toxicity will strengthen the stability of system, while stronger white noise and/or toxicity will result in the extinction of one or two populations. (shrink)

Sinking organic particles transfer ∼10 gigatonnes of carbon into the deep ocean each year, keeping the atmospheric CO2 concentration significantly lower than would otherwise be the case. The exact size of this effect is strongly influenced by biological activity in the ocean's twilight zone (∼50–1,000 m beneath the surface). Recent work suggests that the resident zooplankton fragment, rather than ingest, the majority of encountered organic particles, thereby stimulating bacterial proliferation and the deep‐ocean microbial food web. Here we speculate that (...) this apparently counterintuitive behaviour is an example of ‘microbial gardening’, a strategy that exploits the enzymatic and biosynthetic capabilities of microorganisms to facilitate the ‘gardener's’ access to a suite of otherwise unavailable compounds that are essential for metazoan life. We demonstrate the potential gains that zooplankton stand to make from microbial gardening using a simple steady state model, and we suggest avenues for future research. (shrink)

Intraspecific niche variation can differentially impact community processes and can represent the initial stages of adaptive radiation. Here we test for intraspecific differences in niche use in a keystone species, the alewife (Alosa pseudoharengus). To test whether feedbacks between predator foraging traits and prey communities have led to differences in niche use, we compare the diet composition and trophic position of anadromous and landlocked alewife populations. These populations differ in phenotypic traits related to foraging (gill raker spacing, gape width, and (...) prey selectivity). Trait differences appear to have resulted from eco-evolutionary feedbacks between alewives and their zooplankton prey, and suggest that these two life history forms are exploiting different niches. Direct diets show that anadromous alewives consume a greater biomass of predatory copepods than do landlocked alewives. Anadromous alewives also consume more ostracods—a littoral prey item—as the growing season progresses. These diet differences do not translate into a significant difference in trophic position, as estimated from stable isotopes. However, stable-isotope estimates of diet source show that during early fall, anadromous alewives obtain significantly more of their dietary carbon from the littoral food web. This increased reliance on littoral prey is likely a result of a diet switch that occurs in response to the alewife-driven exhaustion of large-bodied prey items available in the pelagic zone, i.e., alewife niche construction. These findings show the existence of important intraspecific niche differences in the alewife and support the role of eco-evolutionary feedbacks in shaping these niche differences. The initiation of alewife divergence is the result of dam building by humans. Therefore, alewife niche differentiation can be considered to be an eco-evolutionary byproduct of human cultural niche construction. (shrink)

Chapter 9 tracks a different kind of metal-ling (meddling). An honoring of what might be (loosely) ciphered as muck. The indigenous teacher frequented by my wife and me for more than a decade now, insists continuously that the prime modality of genuine spirituality today is something like “compost”—the need to learn how to “cook up” waste and brokenness into a matrix of possibility and fecundity. This foray rehearses what such might look like in tacking back and forth between first century (...) Palestinian “vision-questing” on the part of stone-mason Jesus, re-learning Transjordanian scree as vocational spirit-agents, and an inner-city Detroit version of shamanic alchemy, transfiguring junk-yard waste such as car-hoods into images of divinity and shared humanity by way of “spirited” scavenging and bright-color splashing, uplifting debris into epiphany. Thus, we move from earth detritus to the industrial version. The re-schooling of the Nazarene is directed by the Water Maverick, Baptizer John, himself apparently “retooled” at the hands of East Bank-dwelling bedouin, bringing Israel’s pastoral nomad origins and wisdom back into the West Bank mix. Going back through the waters under such hands, Jesus finds himself “scanned” by a Rock-Presence full of voice and test and finally “revelation.” In juxtaposition to such, the Detroit installation-initiative—a scant mile from the author’s home of 23 years—discloses a resurrection of Black urban struggle as a fragile-but-durable “spirit-sally” against the decimations of white-flight abandonment, animated by listening to and re-purposing (largely) white waste. Though immersed in global capital’s “fly-dumping” discards, the Heidelberg Project (named for its settler colonial street of origin) exhibits a “spirituality of monstrosity” kindred to the quest of this writing, re-purposing the natural “creatures” (wood, iron, algae/zooplankton remade as plastic, plant fiber as canvas, etc.) enslaved, maimed, re-engineered, and dispossessed by market and consumption, into a vocation of revelation and offering—in keeping with the best of gospel music’s sonic innovation, transmuting ugliness and depression into beauty and inspiration. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:A Far-Future Paleontology: The Baffling Case of Brunaspis enigmaticaAnne-Sophie Milon (bio) and Jan Zalasiewicz (bio)Paleontologists, for more than two centuries, have studied and debated the petrified remains of plants and animals that have evolved over the past three billion years on Earth. They have argued over the grand concepts that they reveal, such as biological evolution and climate change, and also the many specific questions thrown up by these (...) relics: was such-and-such a shell, a mollusk, or an arthropod? Did this fossil fish live high up in the water, among the plankton, or grub in the mud on the sea floor?These studies have for many paleontologists been a blessedly human-free zone, detached from the busy realities of our everyday lives. The science of paleontology, though, is simply one obscure part of a burgeoning and rapidly evolving technosphere that underpins our lives, and that is now evolving millions of new kinds of fossils—technofossils—far more rapidly than ever happened in biological evolution. Many of these objects will, quite certainly, become part of Earth’s future fossil record.If such an endeavor as paleontology were ever to arise again, in a distant post-human future, how would its practitioners deal with these bizarre relics?We provide a preview, on the following pages, of just one such enigma, and how it may be resolved (or not) by our puzzled disciplinary descendants. [End Page 31] Click for larger view View full resolution[End Page 32] Click for larger view View full resolution[End Page 33] Click for larger view View full resolution[End Page 34] Click for larger view View full resolution[End Page 35] Click for larger view View full resolution[End Page 36] Click for larger view View full resolution[End Page 37] Click for larger view View full resolution[End Page 38] Click for larger view View full resolution[End Page 39] Click for larger view View full resolution[End Page 40] Click for larger view View full resolution[End Page 41] Click for larger view View full resolution[End Page 42] Click for larger view View full resolution[End Page 43] Click for larger view View full resolution[End Page 44]Anne-Sophie Milon Anne-Sophie Milon is an artist-researcher who applies her illustration skills (HEAR, Strasbourg, France, 2010) and 2D traditional animation (UWE, Bristol, UK, 2012) to political arts (SPEAP, Sciences Po, 2015) and science and technology studies (HSTS, EHESS, 2022). For the past ten years, she has translated geological narratives–and ordinary ones for Earth sciences–into extraordinary plots for the uninitiated, including the humanities. She is currently working with Jan Zalasiewicz on a play, The Petrified Museum (2024), based on the British Geological Survey (Keyworth, UK), and on a PhD project in science and technology studies looking at limestones’ agencies in extractive industry practices (2025). She regularly collaborates with researchers from the Anthropocene Working Group: The Cosmic Oasis (Oxford University Press, 2022), “The Victims of Carbon Dioxide are Starting to Appear” in Feral Atlas (2021), and The Epochs of Nature (University of Chicago Press, 2016).Jan Zalasiewicz Jan Zalasiewicz is Emeritus Professor of Paleobiology at the University of Leicester. He was formerly a field geologist and paleontologist with the British Geological Survey, involved in the geological mapping of eastern England and central Wales. His interests include Early Paleozoic fossils, notably the graptolites (a kind of extinct zooplankton), mud and mudrocks, the Quaternary Ice Ages, the nature of geological time, and the geology made by humans. In recent years, he has helped develop the concept of an Anthropocene epoch. He enjoys writing popular science articles and books, and being involved in art/science projects.Copyright © 2023 Johns Hopkins University Press and SubStance, Inc... (shrink)

The interaction of humans, cholera bacteria, the zooplankton host of the bacterium, and the environment in the case of cholera can be employed to make reasonable predictions about this climate-driven disease. The issues are truly international and represent those that comprise a global scientific enterprise and encompass many other infectious diseases.

Ocean biology helps regulate global climate by fixing atmospheric CO2 and exporting it to deep waters as sinking detrital particles. New observations demonstrate that particle fragmentation is the principal factor controlling the depth to which these particles penetrate the ocean's interior, and hence how long the constituent carbon is sequestered from the atmosphere. The underlying cause is, however, poorly understood. We speculate that small, particle‐associated copepods, which intercept and inadvertently break up sinking particles as they search for attached protistan prey, (...) are the principle agents of fragmentation in the ocean. We explore this idea using a new marine ecosystem model. Results indicate that explicitly representing particle fragmentation by copepods in biogeochemical models offers a step change in our ability to understand the future evolution of biologically‐mediated ocean carbon storage. Our findings highlight the need for improved understanding of the distribution, abundance, ecology and physiology of particle‐associated copepods. (shrink)