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Information processing is increasingly recognized as a fundamental component of life in variable environments, including the evolved use of environmental cues, biomolecular networks, and social learning. Despite this, ecology lacks a quantitative framework for understanding how population, community, and ecosystem dynamics depend on information processing. Here, we review the rationale and evidence for 'fitness value of information' (FVOI), and synthesize theoretical work in ecology, information theory, and probability behind this general mathematical framework. The FVOI quantifies how species' per capita population growth rates can depend on the use of information in their environment. FVOI is a breakthrough approach to linking information processing and ecological and evolutionary outcomes in a changing environment, addressing longstanding questions about how information mediates the effects of environmental change and species interactions. [ABSTRACT FROM AUTHOR]

Forecasting the impacts of climate change on species persistence in diverse natural communities requires a way to account for indirect effects mediated through species interactions. In particular, we expect species to experience major changes in competition as they track favorable climates. Here, we combine experimental data with a recently developed theoretical framework based on coexistence theory to measure the impact of climate‐driven range shifts on alpine plant persistence under climate change. We transplanted three co‐dominant alpine perennial species to five elevations, creating a maximum of 5°C increase in average growing‐season temperature. We statistically modeled species' demographic rates in response to the environment and interpolated species' intrinsic ranges—the environmental mapping of reproduction in the absence of competition. We used low‐density population growth rates—species' initial rate of invasion into an established community—as a metric of persistence. Further analysis of low‐density growth rates (LGRs) allowed us to parse the direct impacts of climate change from indirect impacts mediated by shifting competition. Our models predict qualitatively different range shifts for each species based on the climate conditions under which growth rates are maximized and where they are zero. Overall, climate change is predicted to increase the intrinsic (competition free) growth rates of all species, as warmer and wetter conditions increase the favorability of alpine habitat. However, these benefits are entirely negated by increased competition arising from greater overlap between competitors in their intrinsic ranges. Species were highly dispersal limited, which can prevent species from tracking shifting intrinsic ranges by reducing population spread rates. Yet dispersal limitation also promoted species' persistence because it promotes persistence mechanisms. Our study demonstrates the complex pathways by which climate change impacts species' persistence by altering their competitive environment, and highlights how a persistence framework based on LGRs can help disentangle impacts. [ABSTRACT FROM AUTHOR]

Forecasting the impacts of climate change on biological diversity requires better ways to incorporate competitive interactions into predictions of species' range dynamics and persistence. This problem has been studied extensively in a different context by theoreticians evaluating the coexistence of species in spatially heterogeneous environments. Here, we show how spatial coexistence theory can be adapted to provide a mathematical framework for understanding species persistence in competitive communities under climate change. We first show how the spatial low‐density growth rate provides the relevant metric of species persistence along a climate gradient. We then analyse a model of multiple migrating competitors to show how mechanisms contributing to low‐density growth rates quantify the effect of different competitive processes on persistence, and how these processes change in strength with species' asynchronous migration under climate change. Finally, we outline the empirical utility of the framework, showing how the theory can scale up from local measurements of species performance and competitive interactions to range‐scale metrics of persistence. Treating species' range dynamics as a geographical‐scale coexistence problem presents its own set of challenges, but building from a well‐established body of theory may greatly improve the predictability of species persistence in competitive communities under climate change. [ABSTRACT FROM AUTHOR]

Globally, ecosystem services are threatened by increasing urbanization and more variable precipitation patterns driven by climate change. However, how these drivers interact over long-time scales to affect underlying processes remains poorly understood, hindering our ability to predict their long-term consequences. Here, we use long-term data spanning nearly a century to investigate changes in hydrologic attributes for two lakes in the Upper Midwest with urbanizing watersheds. We quantified flashiness-the variability of runoff rate, volume, or stage-level of waterways-to investigate the concurrent impacts of urbanization and climate change on flashiness and flooding potential. Our results indicate that flashiness generally increased for both lakes over the period of 1916-2013, although this overall trend consists of sub-periods of increase and decrease. Increasing impervious surface area has been the stronger driver of flashiness historically; however, our results suggest that the impact of urbanization may reach a threshold, such that saturation effects would cause large magnitude precipitation events to become a relatively stronger driver of flashiness. Increasing flashiness indicates an increase in flooding potential, documented by increases in the 10- and 100-year flood threshold levels as large as 30 cm. Since flashiness is strongly related to the provisioning of multiple ecosystem services, the methodology and results presented here provide a unique approach to gain insight into how non-linear interactions between global change drivers, at multiple time scales, impact the simultaneous provision of multiple services. [ABSTRACT FROM AUTHOR]

Temporal variation can facilitate the coexistence of competitors through the temporal storage effect. However, this theoretical result was derived with the assumption that species have high dispersal rates. Here, I show that limited dispersal diminishes the storage effect in the classical lottery model. Populations become highly clustered during invasion, and population growth rates and extinction probabilities are functions of cluster size. I adopt the term "nucleation" from the physics literature to describe these characteristics. I developed approximations that incorporated nucleation to capture the spatiotemporal dynamics of the simulated model. Using analytical results from these approximations, I show that limited dispersal dampens asynchronous fluctuations in reproduction between species. This makes species appear to be more similar in their growth rate responses to the environment, thus reducing the potential for the storage effect. Theoretical results lead to simple rules relating average dispersal distances to relative reductions in potential coexistence. To demonstrate their use, I perform a preliminary analysis of two plant communities: tropical trees and desert annuals. In both communities, small-seeded species that disperse short distances on average have the strongest reductions in potential coexistence; species with wind- or animal-driven dispersal disperse farther distances, on average, and experience moderate or small reductions. [ABSTRACT FROM AUTHOR]

The storage effect is a mechanism that can facilitate the coexistence of competing species through temporal fluctuations in reproductive output. Numerous natural systems have the prerequisites for the storage effect, yet it has rarely been quantitatively assessed. Here, we investigate the possible importance of the storage effect in explaining the coexistence of tree species in the diverse tropical forest on Barro Colorado Island, Panama. This tropical forest has been monitored for more than 20 years, and annual seed production is asynchronous among species, a primary requirement for the storage effect. We constructed a model of forest regeneration that includes species-specific recruitment through seed, sapling, and adult stages, and we parameterized the model using data for 28 species for which information is known about seedling germination and survival. Simulations of the model demonstrated that the storage effect alone can be a strong mechanism allowing long-term persistence of species. We also developed a metric to quantify the strength of the storage effect in a way comparable to classical resource partitioning. Applying this metric to seed production data from 108 species, the storage effect reduces the strength of pairwise interspecific competition to 11-43% of the strength of intraspecific competition, thereby demonstrating strong potential to facilitate coexistence. Finally, for a subset of 51 species whose phylogenetic relationships are known, we compared the strength of the storage effect between pairs of species to their phylogenetic similarity. The strength of the storage effect between closely related species was on average no different from distantly related species, implying that the storage effect can be important in promoting the coexistence of even closely related species. [ABSTRACT FROM AUTHOR]

How terrestrial ecosystems will accumulate carbon as the climate continues to change is a major source of uncertainty in projections of future climate. Under growth‐stimulating environmental change, time lags inherent in population and community dynamic processes have been posed to dampen, or alternatively amplify, short‐term carbon gain in terrestrial vegetation, but these outcomes can be difficult to predict. To theoretically frame this problem, we developed a simple model of vegetation dynamics that identifies the stage‐structured demographic and competitive processes that could govern the timescales of carbon storage and loss. We show that demographic lags associated with growth‐stimulating environmental change can allow a rapid increase in population‐level carbon storage that is lost back to the atmosphere in later years. However, this transient carbon storage only emerges when environmental change increases the transition of adult individuals into a larger size class that suffers markedly higher mortality. Otherwise, demographic lags simply slow carbon accumulation. Counterintuitively, an analogous tradeoff between maximum adult size and survivorship in two‐species models, coupled with environmental change‐driven replacement, does not generate the transient carbon gain seen in the single‐species models. Instead lags in competitive replacement slow the approach to the eventual carbon trajectory. Together, our results suggest that time lags inherent in demographic and compositional turnover tend to slow carbon accumulation in systems responding to growth‐stimulating environmental change. Only under specific conditions will lagged demographic processes in such systems drive transient carbon accumulation, conditions that investigators can examine in nature to help project future carbon trajectories. [ABSTRACT FROM AUTHOR]