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Deploying onshore wind energy as a cornerstone of future global energy systems challenges societies and decision-makers worldwide. Expanding wind energy should contribute to a more sustainable electricity generation without harnessing humans and their environment. Opponents often highlight the negative environmental impacts of wind energy to impede its expansion. This study reviews 152 studies to synthesize, summarize, and discuss critically the current knowledge, research gaps, and mitigation strategies on the environmental impacts of onshore wind energy. The investigated effects comprise impacts on the abiotic and biotic environment, with birds and bats in particular, noise and visual impacts. Effects are discussed in the context of social acceptance, other energy technologies, and wind energy expansion in forests. This review illustrates that many effects are highly case-specific and must be more generalizable. Studies are biased regarding the research focus and areas, needing more standardized research methods and long-term measurements. Most studies focus on the direct mortality of birds and bats at wind farms and are concentrated in Europe and North America. Knowledge gaps persist for many impact categories, and the efficacy of mitigation strategies has yet to be proven. More targeted, unbiased research is required that allows for an objective evaluation of the environmental impacts of wind energy and strategies to mitigate them. Impacts, such as those on biodiversity, need to be addressed in the context of other anthropogenic influences and the benefits of wind energy. This forms the basis for a socially acceptable, efficient, and sustainable expansion of wind energy. [ABSTRACT FROM AUTHOR]

Model systems in biology expand the research capacity of individuals and the community. Closely related to Arabidopsis, the genus Boechera has emerged as an important ecological model owing to the ability to integrate across molecular, functional, and eco‐evolutionary approaches. Boechera species are broadly distributed in relatively undisturbed habitats predominantly in western North America and provide one of the few experimental systems for identification of ecologically important genes through genome‐wide association studies and investigations of selection with plants in their native habitats. The ecologically, evolutionarily, and agriculturally important trait of apomixis (asexual reproduction via seeds) is common in the genus, and field experiments suggest that abiotic and biotic environments shape the evolution of sex. To date, population genetic studies have focused on the widespread species B. stricta, detailing population divergence and demographic history. Molecular and ecological studies show that balancing selection maintains genetic variation in ~10% of the genome, and ecological trade‐offs contribute to complex trait variation for herbivore resistance, flowering phenology, and drought tolerance. Microbiome analyses have shown that host genotypes influence leaf and root microbiome composition, and the soil microbiome influences flowering phenology and natural selection. Furthermore, Boechera offers numerous opportunities for investigating biological responses to global change. In B. stricta, climate change has induced a shift of >2 weeks in the timing of first flowering since the 1970s, altered patterns of natural selection, generated maladaptation in previously locally‐adapted populations, and disrupted life history trade‐offs. Here we review resources and results for this eco‐evolutionary model system and discuss future research directions. [ABSTRACT FROM AUTHOR]

Anthocyanin pigments are responsible for many of the vivid pink, purple, red, and blue flower colors across angiosperms and frequently vary within and between closely related species. While anthocyanins are well known to influence pollinator attraction, they are also associated with tolerance to abiotic stressors such as extreme temperatures, reduced precipitation, and ultraviolet radiation. Using a comparative approach, we tested whether abiotic variables predict floral anthocyanin in monkeyflowers (Phrymaceae) across western North America. Within two polymorphic species, we found that abiotic variables predicted flower color across their geographic ranges. In Erythranthe discolor , the frequency of pink flowered (anthocyanin producing) individuals was greater in populations with reduced precipitation. In Diplacus mephiticus , the frequency of pink flowered individuals was greater at higher elevations that had reduced precipitation and lower temperatures but less ultraviolet radiation. At the macroevolutionary scale, across two parallel radiations of North American monkeyflowers, species with floral anthocyanins (pink, purple, or red corollas) occupied areas with reduced precipitation in Erythranthe but not Diplacus. However, after accounting for phylogenetic relatedness, we found no evidence for the joint evolution of flower color and environmental affinity in either clade. We conclude that although abiotic stressors may play a role in the evolution of flower color within polymorphic species, we found no evidence that these processes lead to macroevolutionary patterns across monkeyflowers. [ABSTRACT FROM AUTHOR]

Background: Invasive species affect community dynamics and ecosystem functions, but the mechanisms of their impacts are poorly understood. Hypotheses on invasion impact range from Superior Competitor to Novel Function, from Enemy Escape to Microbial Mediation. In this study, we examined the effects of an urban tree invader, Acer platanoides (Norway maple, NM), on a mesic deciduous forest in contrast to its native congener Acer rubrum (red maple, RM) with a split-plot design experiment. A total of 720 maple seedlings were transplanted to 72 plots under 24 trees of three canopy types. The three experimental treatments were removal of resource competition at above- and belowground and removal of leaf-litter effect. Soil moisture and nitrogen-related microbial activities were followed for each plot. Results: We found that partial canopy removal increased canopy openness and light transmission to the forest floor, but to a greater extent under NM than under RM trees. NM seedlings were more shade tolerant than RM seedlings in height growth. During the reciprocal transplantation in the mixed forest, biomass accumulation of NM seedlings under RM trees were twice as much as under NM, while that of RM seedlings under NM trees was 23.5% less than under RM. Soil net nitrification and relative nitrification were significantly higher, but mineralization rate was much lower under NM than under RM trees, which would lead to faster N leaching and lower N availability in the soil. Plots with litter removal had significantly higher seedling mortality due to herbivory by the end of 2 years, especially for NM seedlings under NM trees. Trenching enhanced soil water availability but there was no difference among canopy types. Conclusions: Our results demonstrated that invasion of NM not only altered forest canopy structure but also changed herbivory rate for seedlings and N dynamics in the soils. NM seedlings were more shade tolerant under NM canopies than RM seedlings and were more protected by NM litter under NM canopies than under RM canopies. These altered biotic and abiotic environments will likely facilitate further invasion of NM in the forests, hence positive feedbacks, and make it an increasingly serious tree invader in North America. [ABSTRACT FROM AUTHOR]

Research on the potential causes of population fluctuations in small mammals generally has focused more on biotic than abiotic factors. In this study, we asked whether the rate of population change of 2 widespread small rodents in deciduous forests of North America are associated with a set of weather events expected to affect the rodents either directly or indirectly. We analyzed a long-term (1995–2016) livetrapping data set from 6 field plots in southeastern New York, estimated rates of population change for white-footed mice and eastern chipmunks, and asked whether these rates are associated with any of a set of 5 weather variables selected a priori. Rates of population change of white-footed mice (Peromyscus leucopus), but not of chipmunks (Tamias striatus), were significantly lower during hurricane than non-hurricane years and in summers with drought than in non-drought summers. Reduced population growth of white-footed mice occurred during the same or subsequent season but we detected no longer-term effects. Neither species was affected by autumn precipitation, summer heat waves, or winter cold. Hurricane- and drought-induced changes in abundance of white-footed mice could affect their short-term interactions with prey (e.g. gypsy moth pupae, tree seeds, and songbird eggs) and parasites (e.g. ticks and zoonotic pathogens). [ABSTRACT FROM AUTHOR]

Aim Large-scale patterns linking energy availability, biological productivity and diversity form a central focus of ecology. Despite evidence that the activity and abundance of animals may be limited by climatic variables associated with regional biological productivity (e.g. mean annual precipitation and annual actual evapotranspiration), it is unclear whether plant-granivore interactions are themselves influenced by these climatic factors across broad spatial extents. We evaluated whether climatic conditions that are known to alter the abundance and activity of granivorous animals also affect rates of seed removal. Location Eleven sites across temperate North America. Methods We used a common protocol to assess the removal of the same seed species ( Avena sativa) over a 2-day period. Model selection via the Akaike information criterion was used to determine a set of candidate binomial generalized linear mixed models that evaluated the relationship between local climatic data and post-dispersal seed predation. Results Annual actual evapotranspiration was the single best predictor of the proportion of seeds removed. Annual actual evapotranspiration and mean annual precipitation were both positively related to mean seed removal and were included in four and three of the top five models, respectively. Annual temperature range was also positively related to seed removal and was an explanatory variable in three of the top four models. Main conclusions Our work provides the first evidence that energy and precipitation, which are known to affect consumer abundance and activity, also translate to strong, predictable patterns of seed predation across a continent. More generally, these findings suggest that future changes in temperature and precipitation could have widespread consequences for plant species composition in grasslands, through impacts on plant recruitment. [ABSTRACT FROM AUTHOR]

• Wider lines had greater light and diurnal temperature/humidity fluctuations. • South-facing and west-facing edges were most affected by abiotic edge effects. • Edge effects extended up to 10 m from the edge into the forest. • Regeneration increased by 5.8 times for each 10-fold increase in light intensity. Ecological impacts of linear anthropogenic disturbances may be underestimated due to edge effects extending into adjacent forests. Seismic lines are the most pervasive linear disturbance associated with oil and gas development in the boreal forests of western North America. The width and orientation of seismic lines may influence microclimatic edge effects that could alter biotic responses, including tree recruitment. We examined light intensity, air temperature, relative humidity, and tree regeneration within seismic lines and adjacent forests to: (1) compare abiotic conditions between wide (6–8 m) and narrow (3–4 m) seismic lines; (2) quantify microclimatic edge effects of seismic lines of different widths and orientations; and (3) relate patterns in tree regeneration density to local patterns in the abiotic environment. We sampled interior forests and 24 seismic lines that were wide or narrow and orientated east-west or north-south in poor mesic ecosites of northeast Alberta, Canada. Microclimatic conditions in seismic line centres were generally intermediate between interior forest and well pads, with narrow seismic lines more similar to interior forest and wide seismic lines more similar to well pads. Light intensity on wide seismic line centres was at least 1.5 times higher than on narrow seismic line centres and up to 3.8 times higher than interior forest. Edge effects on light intensity extended up to 10 m into the forest adjacent to wide lines, but were restricted to the forest edge (at the interface) of narrow lines. Compared to interior forest, day temperature was up to 2.8 °C and 0.8 °C higher at edges of wide and narrow seismic lines, respectively. Relative humidity during the day was up to 7.3% and 3% lower at the edges of wide and narrow seismic lines, respectively, as compared to interior forest. At night, wide seismic line centres were up to 1.7 °C cooler and up to 8.2% more humid than narrow seismic line centres. Tree regeneration was highest where light intensity was highest (the centre of wide north-south seismic lines) and a 10-fold increase in light intensity resulted in 5.8 times more regenerating trees. This study reveals that seismic line width and orientation affect abiotic factors within the linear disturbance and up to 10 m into the adjacent forest. Edge effects on the microclimate of seismic lines were most pronounced in wider seismic lines and along north (south-facing) forest edges. These findings provide a better understanding of the abiotic factors influencing biotic responses to linear anthropogenic disturbances. [ABSTRACT FROM AUTHOR]