Anthropocene Theater and the Shakespearean Stage

Plant communities are more sensitive than soil microbial communities to multiple environmental changes in the Eurasian steppe

It is widely understood that anthropogenic environmental change has great potential to adversely affect human health. But the processes and pathways leading to illness are often (at least initially) poorly understood, which makes calls for reversing behavior that causes environmental change difacult. Yet despite the ever-present risk of confounding those they seek to persuade, scholars and activists from a broad range of disciplines and issue areas are nevertheless increasingly framing environmental issues in public health terms. Can concern over adverse health outcomes attributed to human activities be an effective motivator for social change? If so, can such concern catalyze changes within institutions charged with managing human-environmental interaction? The three books reviewed in this essay suggest three conclusions. The arst is that concern for public health is indeed an effective catalyst for initiating debate on environmental issues. Second, framing environmental change through its health consequences depends on analysis from a range of disciplines, which runs the risk of confusing, instead of convincing, target audiences. Third, despite the inherent analytical complexity, concern for public health will increasingly be used to justify attempts to radically alter the governance of human-environmental interactions. Framing adverse anthropogenic environmental change as a public health threat featured prominently in early inouential work associated with the emergence of environmentalism as a social movement oriented towards institutional change. While Silent Spring is best remembered for illustrating how indiscrimi-

The effects of natural and anthropogenic environmental changes on ecosystem processes at the catchment scale

Parasites are part of ecosystems and can regulate populations. The diseases they cause may negatively impact wildlife, sometimes linked to the imbalance created by anthropogenic environmental changes. Mexico harbors more than 10% of the world's avifauna, but there have been few studies on gastrointestinal (GIT) parasites in wild birds of Mexico. The aim of this review was to provide a comprehensive summary of knowledge on GIT parasites of Mexican wild birds and offer suggestions for approaches for future parasitological research on birds in Mexico. We analyzed 85 documents reporting gastrointestinal parasites in wild birds in Mexico. Overall, 73 genera and 96 bird species were reported as hosts for gastrointestinal parasites, representing approximately 8.17% of the bird species richness in Mexico, with the Anseriformes and Pelecaniformes being the most studied hosts. A total of 187 gastrointestinal parasite species have been identified to species level; the least studied phyla are Metamonada and Apicomplexa. Gastrointestinal parasites have been detected in 30 states; the central region of Mexico has been best studied. Game and aquatic species have been the most studied hosts, with few parasitological studies on nonaquatic bird species. Further studies are needed to understand the host-parasite relationships in Mexican landbirds, the diversity of parasites, the ecological factors underlying parasitism, and the impact of parasites in Mexican wild birds under anthropogenic changes.

Human-induced environmental and climate change are widely blamed for causing rapid global biodiversity loss, but direct estimation of the proportion of biodiversity lost at local or regional scales are still infrequent. This prevents us from quantifying the main and interactive effects of anthropogenic environmental and climate change on species loss. Here, we demonstrate that the estimated proportion of species loss of 252 key protected vertebrate species at a county level of China during the past half century was 27.2% for all taxa, 47.7% for mammals, 28.8% for amphibians and reptiles and 19.8% for birds. Both human population increase and species richness showed significant positive correlations with species loss of all taxa combined, mammals, birds, and amphibians and reptiles. Temperature increase was positively correlated with all-taxa and bird species loss. Precipitation increase was negatively correlated with species loss of birds. Human population change and species richness showed more significant interactions with the other correlates of species loss. High species richness regions had higher species loss under the drivers of human environmental and climate change than low-richness regions. Consequently, ongoing human environmental and climate changes are expected to perpetuate more negative effects on the survival of key vertebrate species, particularly in high-biodiversity regions.

Conference on Remote Sensing, Natural Hazards, and Environmental Change; Singapore, 28–29 July 2011 Natural hazards and anthropogenic environmental changes, both significant in the Asia‐Pacific region, were the two themes of a conference organized by the National University of Singapore's Centre for Remote Imaging, Sensing and Processing (CRISP) and the Université Blaise Pascal's Laboratoire Magmas et Volcans. The application of satellite imagery at a wide range of resolutions, from 500 meters to 50 centimeters, was a unifying approach in many of the studies presented. The recent arrival of a new generation of satellites with extremely high resolution (50 centimeters) has improved scientists' ability to carry out detailed studies of natural hazards and environmental change.

Anthropogenic environmental change can affect species directly by altering physiological rates or indirectly by changing competitive outcomes. The unknown strength of competition-mediated indirect effects makes it difficult to predict species abundances in the face of ongoing environmental change. Theory developed with phenomenological competition models shows that indirect effects are weak when coexistence is strongly stabilized, but these models lack a mechanistic link between environmental change and species performance. To extend existing theory, we examined the relationship between coexistence and indirect effects in mechanistic resource competition models. We defined environmental change as a change in resource supply points and quantified the resulting competition-mediated indirect effects on species abundances. We found that the magnitude of indirect effects increases in proportion to niche overlap. However, indirect effects also depend on differences in how competitors respond to the change in resource supply, an insight hidden in nonmechanistic models. Our analysis demonstrates the value of using niche overlap to predict the strength of indirect effects and clarifies the types of indirect effects that global change can have on competing species.

Urban ecosystems are profoundly modified by human activities and thereby provide a unique ‘‘natural laboratory‘‘ to study potential ecosystem responses to anthropogenic environmental changes. Because urban environments are now affected by urban heat islands, carbon dioxide domes, and high-level nitrogen deposition, to some extent they portend the future of the global ecosystem. Urbanization in the metropolitan region of Phoenix, Arizona (USA) has resulted in pronounced changes in air temperature (Tair), atmospheric CO2 concentration, and nitrogen deposition (Ndep). In this study, we used a process-based ecosystem model to explore how the Larrea tridentata dominated Sonoran Desert ecosystem may respond to these urbanization-induced environmental changes. We found that water availability controls the magnitude and pattern of responses of the desert ecosystem to elevated CO2, air temperature, N deposition and their combinations. Urbanization effects were much stronger in wet years than normal and dry years. At the ecosystem level, aboveground net primary productivity (ANPP) and soil organic matter (SOM) both increased with increasing CO2 and Ndep individually and in combinations with changes in Tair. Soil N (Nsoil) responded positively to increased N deposition and air temperature, but negatively to elevated CO2. Correspondingly, ANPP and SOM of the Larrea ecosystem decreased along the urban‐suburban‐ wildland gradient, whereas Nsoil peaked in the suburban area. At the plant functional type (FT) level, ANPP generally responded positively to elevated CO2 and Ndep, but negatively to increased Tair .C 3 winter annuals showed a greater ANPP response to higher CO2 levels (>420 ppm) than shrubs, which could lead over the long term to changes in species composition, because competition among functional groups is strong for resources such as soil water and nutrients. Overall, the combined effects of the three environmental factors depended on rainfall variability and nonlinear interactions within and between plant functional types and environmental factors. We intend to use these simulation results as working hypotheses to guide our field experiments and observations. Experimental testing of these hypotheses through this process should improve our understanding of urban ecosystems under increasing environmental stresses.

Climatic versus human impact on the Holocene sedimentation in river valleys of different order: Examples from the upper Dnieper basin, Belarus

Anthropogenic environmental change is altering the behavior of animals in ecosystems around the world. Although behavior typically occurs on much faster timescales than demography, it can nevertheless influence demographic processes. Here, we use detailed data on behavior and empirical estimates of demography from a coral reef ecosystem to develop a coupled behavioral-demographic ecosystem model. Analysis of the model reveals that behavior and demography feed back on one another to determine how the ecosystem responds to anthropogenic forcing. In particular, an empirically observed feedback between the density and foraging behavior of herbivorous fish leads to alternative stable ecosystem states of coral population persistence or collapse (and complete algal dominance). This feedback makes the ecosystem more prone to coral collapse under fishing pressure but also more prone to recovery as fishing is reduced. Moreover, because of the behavioral feedback, the response of the ecosystem to changes in fishing pressure depends not only on the magnitude of changes in fishing but also on the pace at which changes are imposed. For example, quickly increasing fishing to a given level can collapse an ecosystem that would persist under more gradual change. Our results reveal conditions under which the pace and not just the magnitude of external forcing can dictate the response of ecosystems to environmental change. More generally, our multiscale behavioral-demographic framework demonstrates how high-resolution behavioral data can be incorporated into ecological models to better understand how ecosystems will respond to perturbations.

The human species has been altering the environment over large geographic areas since the domestication of fire, plants, and animals. The progression from hunter to farmer to technologist has increased the variety and pace more than the geographic extent of human impact on the environment. A number of regions of the earth have experienced significant climatic changes closely related in time to anthropogenic environmental changes. Plausible physical models suggest a causal connection. The magnitudes of probable anthropogenic global albedo changes over the past millennia (and particularly over the past 25 years) are estimated. The results suggest that humans have made substantial contributions to global climate changes during the past several millennia, and perhaps over the past million years; further such changes are now under way.

Anthropogenic environmental change, including climate change and urbanization, results in warmer temperatures in both terrestrial and aquatic habitats and changes in community assemblages including invasive species introductions, among many other alterations. Anurans are particularly susceptible to these changes because generally they have a biphasic lifecycle and rely on aquatic and terrestrial habitats for survival. Changes such as warmer water temperature can result in direct and carryover effects, after metamorphosis that decrease fitness. However, Gulf Coast toads (Incilius (Bufo) nebulifer) are expanding their range, including into anthropogenically disturbed areas. We hypothesize that I. nebulifer copes with warmer water, reduced water levels, and invasive species by altering their physiology and/or behavior. Corticosterone is the primary glucocorticoid in amphibians, and it modulates many aspects of physiology and behavior, potentially including lipid storage and hop performance, during unpredictable (stressful) events. As a true toad, I. nebulifer also produces bufadienolide toxins that aid in its antipredator defense and may have tradeoffs with corticosterone. In a fully factorial design, we measured baseline corticosterone levels in tadpoles in response to two treatments: decreased water levels and increased water temperatures. After metamorphosis, we measured the corticosterone profile and other associated responses to exposure to the predatory red imported fire ant (Solenopsis invicta; RIFA). We found that tadpoles had elevated baseline corticosterone release rates when reared in warmer water and reduced water levels. Toadlets also had elevated baseline corticosterone release rates when exposed to any combination of two of the three treatments but when exposed to all three treatments toadlets instead showed elevated magnitude of their stress response. Predator avoidance (as measured by hop performance) was reduced after exposure to RIFA. Tadpoles from warmer water developed more quickly and were smaller in mass after metamorphosis. Toadlets had reduced production of two of the three detected bufadienolides and increased energy storage (lipids) after exposure to warmer water and reduced growth after exposure to reduced water levels. We found direct and carryover effects of common anthropogenic changes in I. nebulifer that may aid in their ability to persist despite these changes.

Anthropogenic environmental change can impact community and population traits such as species diversity and population densities, which have been shown to influence the prevalence of viruses in wildlife reservoirs. In particular, host species resilient to changes in their natural habitat may increase in numbers, which in turn can affect the prevalence of directly transmitted viruses. We have carried out a survey of small mammal communities in three tropical landscapes differing in their degree of environmental change in Central Panama and investigated the effects of community changes on Hepacivirus prevalence. The modification of continuous habitat into partly connected or isolated habitat patches during the past century was linked to changes in species diversity and species assemblages, which was further associated with shifts in the abundance of generalist marsupial (Didelphis marsupialis, Philander opossum) and rodent (Proechimys semispinosus) species. The latter has become dominant in isolated habitat patches and was the only identified Hepacivirus host in our study system. Our analyses suggest that, in addition to the effects of host age and sex, host population density in interaction with sex ratio is a crucial predictor of infection probability. Although we found no significant relationships between species diversity per se and infection probability, the lowest prevalence detected in the landscape with the highest species diversity indicates that shifts in species assemblages (e.g. changes in the presence and abundance of marsupial predators) impact the host's intraspecific contact rates, the probability of virus transmission and, thus, the virus prevalence. Our study additionally provides important data on the influence of human-induced landscape changes on infection probability and, therefore, on virus prevalence in wildlife and emphasizes the importance of a landscape-scale approach with concomitant consideration of the complex interactions between ecological factors.

Despite the decades-long recognition of the importance of scaling in ecology, our knowledge about many ecological patterns and processes is still largely restricted to particular spatial and temporal scale domains with relatively narrow ranges. There is no exception when it comes to the study of biodiversity, one of the most important and active research fields in ecology. Increasing work suggests that such narrow ranges of scales are in most cases inadequate for addressing conservation challenges associated with biodiversity change. The need for understanding how biodiversity is shaped and will change across different scales is stronger than ever. Here, we review recent progresses of up-scaling and down-scaling biodiversity in the context of global environmental change, with focus on two relatively large spatial scale domains, i.e., the landscape and macroecological scales. Landscape ecology and macroecology are both active, but so-far poorly connected research fields. They share a common central motivation of unraveling spatial patterning of biodiversity and the underlying mechanisms. Our literature review suggests that landscape-scale processes may exert unexpected up-scaling effects to shape biodiversity patterns at macroecological scales, while macroecological processes may generate a range of down-scaling effects on landscape biodiversity. Specifically, although there is a lack of consensus on the underlying mechanisms, it is likely that landscape processes scale up through connectivity and feedback loops within and across landscapes to affect macroecological biodiversity responses. On the other hand, the down-scaling effects of macroecological processes on biodiversity is often confounded with small-scale processes, leading to various responses inconsistent with direct down-scaling extrapolations. In addition, the temporal dimension is indispensable to investigating effects and mechanisms of cross-scale processes. Specifically, long-term (decades and beyond) perspectives are necessary for re-evaluating ecological knowledge obtained from biodiversity responses to short-term environmental changes and recognizing historical legacies of both landscape and macroecological processes on biodiversity at the two spatial scales. Overall, scaling analyses of ecological processes across spatial extents ranging from small habitats to the globe have revealed biodiversity responses to anthropogenic environmental changes as inconsistent with assumptions and extrapolations based on extant ecological knowledge at a few fixed scales. Such analyses are needed to better inform conservation actions and planning practiced mainly at local to macroecological scales. We suggest that elucidating cross-scaling mechanisms and accumulating long-term time series at multiple spatial scales are key to linking landscape ecology and macroecology in terms of biodiversity dynamics. Such efforts would be an important contribution to the ecological basis for managing biodiversity change in the Anthropocene, as these dynamics involve multiple up-scaling and down-scaling processes over time.

Sediment magnetic record of anthropogenic environmental changes in the catchment of a typical submerged macrophyte-dominated lake over the last approximately 168 years.