University of Maine
  • Orono, Maine, United States
Recent publications
FRANCO-AMERICAN NEWSPAPERS AND PERIODICALS Franco-American newspapers and periodicals occupy an overlapping space between primary and secondary literature, and their shadow looms large over the collective body of historic Franco-American sources. Their significance to the Franco-American community is hard to overstate. These periodical publications complicate issues of identity in the U.S. Northeast and are an integral part of Québec history itself. This article details current work to inventory newspaper and periodical titles (currently over 400) and makes accessible our collectively built, evolving inventory of Franco-American newspapers. Les journaux et périodiques franco-américains occupent un espace entre la littérature primaire et la littérature secondaire, et leur ombre plane sur le corpus collectif des sources historiques franco-américaines. Leur importance pour la communauté franco-américaine est difficile à surestimer. Ces publications périodiques compliquent les questions d'identité dans le Nord-Est américain et font partie intégrante de l'histoire même du Québec. Cet article détaille les travaux en cours pour recenser les titres de journaux et de périodiques (présentement plus de 400) et rend accessible notre inventaire construit collec-tivement des journaux franco-américains. It is no surprise that scholars value the U.S. ethnic press. These newspapers both complement and counter English-language, mainstream newspapers of their time. They echo the personal and political interests of multi-generational migrant populations that cultivated institutions of business, worship, and learning in the U.S. These publications can show a diversity frequently obscured by overgeneralization. Titles reflect local concerns, express varied political affiliations, represent a range of social, religious, and cultural issues, publish serialized literature, and engage in transnational and transoceanic dialogues. Sally Miller's foundational anthology and handbook argues:
Premise: Plant traits and insect herbivory have been highly studied within the modern record but only to a limited extent within the paleontological. Preservation influences what can be measured within the fossil record but modern methods are also not compatible with paleobotanical methods. To remedy this knowledge gap, a comparable framework was created here using modern and paleobotanical methods allowing for future comparisons within the fossil record. Methods: Insect feeding damage on selected tree species at Harvard Forest, the Smithsonian Environmental Research Center, and La Selva was quantified using the damage type system prevalent within paleobotanical studies, and compared to leaf traits. Linear models and random forests analyses tested the influence of leaf traits on total, specialized, gall, and mine frequency and diversity. Results: Structural traits like LMA and palatability traits including lignin and phosphorus concentrations are important variables affecting gall and mine damage. The significance and strength of trait‐herbivory relationships varied across forest type, which is likely driven by differences in local insect populations. Conclusions: This work addresses the persistent gap between modern and paleoecological studies focusing on the influence of leaf traits on insect herbivory. This is important as modern climate change alters our understanding of plant‐insect interactions providing a need for contextualizing these relationships within evolutionary time. The fossil record provides information on terrestrial response to past climatic events and thus, should be implemented when considering how to preserve biodiversity under current and future global change. This article is protected by copyright. All rights reserved.
CNF suspensions were set to 80% or more and 1.8% or less, respectively. If the solids content of the CNF solutions was high and the fibrillation level was low, plugging was experienced in the spray head because of the high viscosity of the suspensions, resulting in production of poor-quality powders. In terms of reduction in processing energy, even if the CNF suspension solids content was increased to 1.5 wt.%, the powder quality and the production yields were excellent. It was confirmed that high-quality powder under 20 µm were produced at a 90% fibrillation level of all CNF feedstocks. The resulting dry CNF powders were characterized to determine particle size distributions and morphological properties via a scanning electron microscope and a laser diffraction particle size analyzer. The particle sizes were smaller at higher fibrillation levels and lower solids content of the CNF suspensions. The CNF suspension derived from bleached kraft pulp, the average particle size decreased by 43% and 33% with the lowered solids contents from 1.8 to 1%, and the increased fineness levels from 80 to 100%, respectively. Keywords Cellulose nanofibrils · Spray drying · Bleached kraft pulp · Unbleached kraft pulp · Old corrugated cardboard pulp Abstract Three types of wood pulp feedstocks including bleached softwood kraft, unbleached soft-wood kraft and old corrugated containers were disk refined to produce cellulose nanofibrils at different fineness levels ranging from 50 to 100%, and the resulting aqueous suspensions of cellulose nanofi-brils were spray dried. The spray drying experiments were carried out to examine different processing conditions for the different CNF feedstock types and fines level at various suspension concentrations to produce dry samples with free-flowing powder morphologies. The fineness levels and solids contents of Supplementary Information The online version contains supplementary material available at https:// doi.
Raymond Kelly’s widely cited Warless Societies and the Origin of War (University of Michigan Press, 2000) seeks to explain the origins of two central signatures of human society: war and segmented—i.e., multilevel—societies. Both, he argues, arose with the emergence of a social-substitutability principle, a rule that establishes a collective identity among a set of individuals such that any one member becomes equivalent to, and responsible for the actions of, the others. This principle emerged during the Holocene, when population increase gave rise to the first lethal ambushes. By its nature, ambush obscures attackers’ identities. Those attempting to retaliate for the ambush were therefore obliged to target members of the ambushers’ group indiscriminately—i.e., based on a social-substitutability principle. Kelly’s proposals draw welcome attention to a widespread, deeply influential, and unsettling human behavior, the disposition to hold everyone in a group culpable for the actions of a few, a proclivity that all too often results in mass slaughter. His general argument, however, is logically and empirically deficient, and cross-cultural evidence on ambush in contact-era New Guinea undermines his anonymity-of-ambush hypothesis. What then accounts for war and multilevel society? The New Guinea evidence strongly supports a contention that social-substitutability behavior arose not from offensive military action (i.e., ambush) but from the defensive military response to ambush. These findings render the social-substitutability argument’s unconventional definition of war superfluous, undermine its chronology for the emergence of war, and underwrite an alternative scenario for the origins of multilevel, segmented society.
Autonomous sensors for gravitational carbon flux in the ocean are critically needed, because of uncertainties in the projected response of the biological carbon pump (BCP) to climate change, and the proposed, engineered acceleration of the BCP to sequester carbon dioxide in the ocean. Optical sediment trap (OST) sensors directly sense fluxes of sinking particles in a manner that is independent of, and complementary to, other autonomous, sensor‐derived estimates of BCP fluxes. However, limited intercalibrations of OSTs with traditional sediment traps and uncharacterized, potential biases have limited their broad adoption. A global field data set spanning three orders of magnitude in carbon flux was compiled and used to develop empirical models predicting particulate organic carbon flux from OST observations, and intercalibrating different sensor designs. These data provided valuable constraints on the uncertainty in the predicted carbon flux and showed a quantitative, theoretically consistent relationship between observations from OSTs with collimated and diffuse optical geometries. While not designed for this purpose, commercial beam transmissometers have been used as OSTs, so two models were developed quantifying the biases arising from the transmissometer's housing geometry and optical beam diameter. Finally, an algorithm for the quality control of beam transmissometer‐derived OST data was optimized using sensitivity tests. The results of this study support the expansion of OST‐based gravitational carbon flux measurements and provide a framework for interpretation of OST measurements alongside other gravitational particle flux observations. These findings also suggest key features that should be included in designs of future, purpose‐built OST sensors.
Modern trends in the world population are on a steep upward climb, with the number of humans on the planet growing from 2.5 billion in 1950 to 4.0 billion in 1974 to 6.0 billion in 1999 to 7.0 billion in 2011 to 7.6 billion in 2018 and reaching 8.0 billion in 2022. In other words, the global population tripled in less than 70 years from 1950 onward. Today, the annual global increase in human population is over 80 million people per year, meaning that the equivalent of another US population is added to the world total approximately every 4 years. In this brief chapter, the discussion focuses on factors contributing to rapid population growth, implications of modern population growth, and policy options for the stabilization of the human population.
Many of us have spent time around and in streams and rivers but perhaps have not given much thought to the ecology and natural history of these aquatic systems. Although each stream or river is unique in its own right, it is the dominant influence of flowing water in these systems that provides a common thread distinguishing streams and rivers as a major class of aquatic resource. At any scale – from local to global – these fluvial ecosystems play a valuable role in the biosphere as habitats and as receptors, transformers, and transporters of water, materials, and energy. In this analysis of stream and river ecosystems, major topics of discussion include environmental conditions in streams and their surrounding watersheds, stream hydrology, habitat structure, stream biota and food webs, energy flow and nutrient-cycling processes, and the ecological effects of disturbances and stress in streams and their drainage basins. In one study from the Mississippi River drainage system, there is a striking example of connections between human farming activities in one region producing adverse ecological impacts in a distant region with a river network acting as the transport medium linking the two locations.
Looking across the rippling surface of a lake, it is not obvious what kinds of biotic interactions and life forms are found in this ecosystem. We see the trout jump and hear the loon call, but we are left with only a glimpse of the true diversity and complexity of the biological community in this aquatic system. What are some of the essential, but often unseen, features of feeding relationships in a lake and how is a lake ecosystem influenced by its surrounding watershed and by physical-chemical conditions in the water column? Included in this analysis of lake ecosystems are descriptions of lake trophic states, habitat zonation, lake stratification patterns and processes, lake biota and food web networks, trophic cascades, energy flow, nutrient cycling processes, and the effects of disturbance and stressors in lakes. In one illustration, a case study is described where a non-native fish predator was introduced to a large African lake in an attempt to create jobs and an edible food resource. Unfortunately, that decision set in motion a sequence of events that resulted in a loss of 150–200 endemic fish species, representing a huge decrease in fish species diversity and a massive simplification of the trophic system in the lake.
From the perspective of biological diversity, there are a few regions on Earth that can compare with the tropics in terms of sheer numbers of species; indeed, tropical rainforests contain an estimated 50% of all species diversity on Earth. The words “astounding” and “overwhelming” are barely adequate to describe the complexity of tropical life forms encompassing more species of orchids, beetles, birds, bats, butterflies, and other members of the plant, animal, and microbe kingdoms than any of us can possibly imagine. In this analysis of tropical ecology, major discussion topics include tropical forest geography, environmental conditions, species diversity patterns and origins, community and landscape ecology, and tropical deforestation. It is noted that one of the unexpected impacts of tropical forest harvesting and deforestation is an interaction with fire disturbance. Fire is regarded as a historical but infrequent factor in Amazonian rainforest disturbance regimes. However, fires have become much more common because of interactions with pasture burning, increased forest fire susceptibility from logging effects on forest edges, as well as El Niῆo influences. Unfortunately, some rainforest areas in Brazil now have fire return intervals of 7–14 years, which is a huge threat to sensitive species.
Much of what happens in terms of ecological interactions in the biosphere occurs within the context of a community – whether terrestrial, aquatic, marine, or otherwise. A biological community is comprised of an assemblage of interacting or potentially interacting species that share a habitat or an ecosystem in common. Within that community setting, a species is forced to respond to a myriad of biotic processes and relationships that help to shape the food web characteristics, species pools, ecological niches, and population abundances that we see in the mosaic fabric of the biosphere. As a means of developing a holistic perspective on community ecology, this chapter explores the nature of ecological interactions involving foraging, competition, trophic relationships, and predation; case studies of trophic cascades; influences of keystone predators in biological communities; mathematical models of species interrelationships; and the application of stable isotopes to the analysis of food webs. In one example of a trophic cascade from Yellowstone National Park, we see that the re-introduction of wolves to the food web created a ripple effect on elk prey, coyote scavengers, vegetation and riparian habitat conditions in the valley bottom, and stream ecology.
Food production is an essential part of the human enterprise on Earth; as such, it is important for us to ask how our farms or agroecosystems are doing from an ecological perspective. This chapter explores the basic attributes of modern agriculture in the context of three major questions. Can our farms feed an ever-growing world human population without compromising environmental quality and human health? Are ecological principles relevant to farming practices and crop production? Can ecological principles help to minimize the adverse impacts of human farming practices? Topics of discussion in the chapter include an overview of food production, concerns with unsustainable water use, excess fertilizer use, herbicides and insecticides, soil degradation, plant genetic diversity, crop genetic modification, antibiotic use in farm animals, and a vision for sustainable agriculture. Looking to the future, it is hoped that sustainable farming practices will greatly expand, with a focus on reducing the carbon footprint of food production and distribution; minimizing weeds and pests with low-impact approaches; minimizing nutrient runoff and pollution; minimizing pesticide use and toxicity; sustaining soil fertility, topsoil, and soil organic matter; maximizing crop yields but with lower inputs of water and nutrients; minimizing transportation expenses and impacts; and diversifying food and crop resources.
The oceans have helped to frame much of the history of our planet, shaping and transforming the surface of the Earth, influencing global climate patterns, and sustaining countless generations of evolving organisms. This chapter explores how complex, diverse, and fascinating ocean ecosystems are in terms of biological, ecological, and environmental characteristics. Chapter topics include marine policy issues, marine geography, communities and food webs, primary production and element cycling, and two contrasting top-down and bottom-up trophic cascades in different marine systems. One of the specific topics highlighted in the chapter is the ecology of coral reef ecosystems, which are well known for their spectacular diversity and productivity but are increasingly at risk from a variety of stresses and disturbances. One of the major threats is the phenomenon of coral bleaching involving the dramatic loss of pigmented endosymbiotic zooxanthellae algae that live within the coral host. Evidence indicates that elevated seawater temperatures induce the death or expulsion of zooxanthellae and the subsequent loss of function in the vital reef symbiosis. Once algal symbionts are gone and the reef turns a bleached white color, the system degrades and may or may not recover.
Some of the most subtle but significant impacts of human activities on modern global change processes have occurred as emissions of airborne substances have disrupted the balance of gases and aerosols in the atmosphere. Initially, there was an implicit assumption that the vast atmosphere could absorb these compounds without any ill effects, but that proved to be false. It is now clear that we have crossed a tipping point marked by serious and undesirable consequences. The changes in atmospheric chemistry stemming from modern anthropogenic emissions present three major challenges: erosion of the protective ozone layer that limits inputs of damaging ultraviolet (UV) radiation to the Earth’s surface, degraded air quality, and enrichment of greenhouse gases that promote warming, climate change processes, and the destabilization of our planet. These multiple atmospheric influences are a major reason why we should be concerned with understanding how the processes of atmospheric chemistry relate to ecosystem health. The atmosphere is an active and major part of the global environment and is of critical importance because of the ways in which it connects and links virtually all parts of the biosphere. This chapter examines relationships involving ozone, acidic deposition, global warming, and climate change.
Populations of species are foundational building blocks in communities and ecosystems throughout the biosphere. How do these populations achieve ecological success and evolutionary fitness? What kinds of processes, factors, and interactions are important influences for populations of species? This chapter explores questions and concepts regarding the ecology of populations, including discussions of population growth and regulation, a case study of the population ecology of the eastern coyote, methods for quantifying and analyzing populations, and concepts of evolutionary biology and behavioral ecology. One illustration from the chapter examines a report of self-medication in the behavioral repertoire of primates in the Mahale Mountains National Park in Tanzania. In this case, a chimp that was very ill with roundworm or schistosomiasis staggered through the forest understory in search of a flowering Vernonia amygdalina shrub, which is not a normal food source. The chimp selected several young shoots, peeled back the bark, and grimaced as she sucked the liquid juice from the pith; within 24 h, the chimp was no longer exhibiting signs of illness. As it turns out, the plant contains two secondary metabolites that provide exceptional anti-parasitic activity. Who would guess that herbal medications would be utilized by non-human primates?
Models in ecology vary widely in form and function. In some cases, ecological models are developed primarily as qualitative conceptual frameworks that serve as tools for organizing what is known about a problem. More often, however, a conceptual model is just the first step in the design and development of a quantitative computer-based model that combines data and insights from ecological analysis and mathematics to produce a numerical representation of an ecological process, pattern, or system. In ecology, models allow us to compile and integrate information and current understanding, to identify gaps in our knowledge base and current understanding, to explore feedbacks and interactions among multiple variables in a study system, to generate questions and hypotheses for empirical testing, to evaluate the apparent sensitivity of ecological relationships and variables, and to make predictions and simulate outcomes of new scenarios. Taken as a whole, the chapter’s contents illustrate how models can serve as powerful synergistic learning tools for advancing understanding in both research and educational applications.
Whether we are interested in brook trout or some other group of organisms, it is important to recognize that the distributions of different organisms can be influenced by variations and combinations of a wide range of environmental parameters. As such, one of our fundamental challenges in ecology is to identify ways to analyze and to interpret environmental variations within the biosphere. This chapter explores the potential ecological influences of environmental gradients, light resources, patterns of moisture and temperature, geological factors, and soil conditions. In one example from the chapter, a gradient from the desert floor to the summit of the Santa Catalina Mountains of Arizona is examined to illustrate the striking changes in environmental conditions that can occur with increasing elevation in the mountains, along with corresponding responses of plant communities to those environmental drivers.
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3,886 members
Elena Korotkikh
  • Institute of Climate Change
Yong-jiang Zhang
  • School of Biology and Ecology
Ivan J Fernandez
  • School of Forest Resources and Climate Change Insitute
Renae Moran
  • School of Food and Agriculture
04469, Orono, Maine, United States