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Danthonia californica Bolander (Poaceae)is a native perennial bunchgrass commonly used in the restoration of prairie ecosystems in the western United States. Plants of this species simultaneously produce both chasmogamous (potentially outcrossed) and cleistogamous (obligately self‐fertilized) seeds. Restoration practitioners almost exclusively use chasmogamous seeds for outplanting, which are predicted to perform better in novel environments due to their greater genetic diversity. Meanwhile, cleistogamous seeds may exhibit greater local adaptation to the conditions in which the maternal plant exists. We performed a common garden experiment at two sites in the Willamette Valley, Oregon, to assess the influence of seed type and source population (eight populations from a latitudinal gradient) on seedling emergence and found no evidence of local adaptation for either seed type. Cleistogamous seeds outperformed chasmogamous seeds, regardless of whether seeds were sourced directly from the common gardens (local seeds) or other populations (nonlocal seeds). Furthermore, average seed weight had a strong positive effect on seedling emergence, despite the fact that chasmogamous seeds had significantly greater mass than cleistogamous seeds. At one common garden, we observed that seeds of both types sourced from north of our planting site performed significantly better than local or southern‐sourced seeds. We also found a significant seed type and distance‐dependent interaction, with cleistogamous seedling emergence peaking approximately 125 km from the garden. These results suggest that cleistogamous seeds should be considered for greater use in D. californica restoration. [ABSTRACT FROM AUTHOR]

Ecological restoration often relies on disturbance as a tool for establishing target plant communities, but disturbance can be a double‐edged sword, at times initiating invasion and unintended outcomes. Here we test how fire disturbance, designed to enhance restoration seeding success, combines with climate and initial vegetation conditions to shift perennial versus annual grass dominance and overall community diversity in Pacific Northwest grasslands. We seeded both native and introduced perennial grasses and native forbs in paired, replicated burned‐unburned plots in three sites along a latitudinal climate gradient from southern Oregon to central‐western Washington. Past restoration and climate manipulations at each site had increased the variation of starting conditions between plots. Burning promoted the expansion of extant forbs and perennial grasses across all sites. Burning also enhanced the seeding success of native perennial grass and native forbs at the northern and central site, and the success of introduced perennial grasses across all three sites. Annual grass dominance was driven more by latitude than burning, with annuals maintaining their dominance in the south and perennials in the north. At the same time, unrestored grasslands surrounding all sites remained dominated by perennial grasses, suggesting that initial plot clearing may have allowed for annual grass invasion in the southern site. When paired with disturbance, further warming may increase the risk of annual grass dominance, a potentially persistent state. [ABSTRACT FROM AUTHOR]

Abstract: Parasite damage strongly affects dynamics of boreal forests. Damage levels may be affected by climate change, either directly or indirectly through changes in properties of host trees. We examined [...]

An investigation of whether different community contexts might change pollinator preference and constancy and thus influence the possibility of hybridization among three Indian paintbrush species is conducted. Pollinator constancy was found to weaken in the hybrid context, an area where the three species co-occurred with morphologically intermediate plants.

Tree diversity inventories were undertaken. The goal of this study was to understand changes in tree community dynamics that may result from common anthropogenic disturbances at the Reserva Los Cedros, a tropical montane cloud forest reserve in northern Andean Ecuador. The reserve shows extremely high alpha and beta tree diversity. We found that all primary forest sites, regardless of age of natural gaps, are quite ecologically resilient, appearing to return to a primary-forest-type community of trees following gap formation. In contrast, forests regenerating from anthropogenic disturbance appear to have multiple possible ecological states. Where anthropogenic disturbance was intense, novel tree communities appear to be assembling, with no indication of return to a primary forest state. Even in ancient primary forests, new forest types may be forming, as we found that seedling community composition did not resemble adult tree communities. We also suggest small watersheds as a useful basic spatial unit for understanding biodiversity patterns in the tropical Andes that confound more traditional Euclidean distance as a basic proxy of dissimilarity. Finally, we highlight the conservation value of Reserva Los Cedros, which has managed to reverse deforestation within its boundaries despite a general trend of extensive deforestation in the surrounding region, to protect a large, contiguous area of highly endangered Andean primary cloud forest. [ABSTRACT FROM AUTHOR]

In 2008, Ecuador recognized the Constitutional Rights of Nature in a global first. This recognition implies a major shift in the human-nature relationship, from one between a subject with agency (humans) and an exploitable object (nature), to a more equilibrated relationship. However, the lack of a standard legal framework has left room for subjective interpretations and variable implementation. The recent widespread concessioning of pristine ecosystems to mining industries has set up an unprecedented conflict and test of these rights. Currently, a landmark case involving Los Cedros Protected Forest and mining companies has reached the Constitutional Court of Ecuador. If Ecuador's highest Court rules in favor of Los Cedros and the Rights of Nature, it would set a legal precedent with enormous impact on biological conservation. Such a policy shift offers a novel conservation strategy, through citizen oversight and action. A ruling against Los Cedros and the Rights of Nature, while a major setback for biodiversity conservation, would be taken in stride by the active social movement supporting these goals, with the case likely moving into international courts. Meanwhile, extractive activities would continue and expand, with known consequences for biodiversity. [ABSTRACT FROM AUTHOR]

Prairies in the Pacific Northwest are dominated by perennial bunchgrasses. A Mycena in the citrinomarginata complex was observed to tightly co-occur with bunchgrasses at several prairie study sites. Mapping and spatial statistics showed that it was strongly and significantly associated with Festuca roemeri tussocks. We further found that this fungus is attached to F. roemeri roots (17/17 examined) and both specific primers and next-generation DNA sequencing established that the fungus is in the roots, suggesting that M. citrinomarginata may be endophytic or biotrophic in some contexts, and not simply saprotrophic. These results combined with a literature review indicate that Mycena species are often found as endophytes in grass roots. Given the importance of grasses and grasslands for humans, this ecological association deserves further study. [ABSTRACT FROM AUTHOR]

Spatial gradients in population growth, such as across latitudinal or elevational gradients, are often assumed to primarily be driven by variation in climate, and are frequently used to infer species' responses to climate change. Here, we use a novel demographic, mixed‐model approach to dissect the contributions of climate variables vs. other latitudinal or local site effects on spatiotemporal variation in population performance in three perennial bunchgrasses. For all three species, we find that performance of local populations decreases with warmer and drier conditions, despite latitudinal trends of decreasing population growth toward the cooler and wetter northern portion of each species' range. Thus, latitudinal gradients in performance are not predictive of either local or species‐wide responses to climate. This pattern could be common, as many environmental drivers, such as habitat quality or species' interactions, are likely to vary with latitude or elevation, and thus influence or oppose climate responses. [ABSTRACT FROM AUTHOR]

Predicting species' range shifts under future climate is a central goal of conservation ecology. Studying populations within and beyond multiple species' current ranges can help identify whether demographic responses to climate change exhibit directionality, indicative of range shifts, and whether responses are uniform across a suite of species.We quantified the demographic responses of six native perennial prairie species planted within and, for two species, beyond their northern range limits to a 3‐year experimental manipulation of temperature and precipitation at three sites spanning a latitudinal climate gradient in the Pacific Northwest, USA. We estimated population growth rates (λ) using integral projection models and tested for opposing responses to climate in different demographic vital rates (demographic compensation).Where species successfully established reproductive populations, warming negatively affected λ at sites within species' current ranges. Contrarily, warming and drought positively affected λ for the two species planted beyond their northern range limits. Most species failed to establish a reproductive population at one or more sites within their current ranges, due to extremely low germination and seedling survival. We found little evidence of demographic compensation buffering populations to the climate treatments.Synthesis. These results support predictions across a suite of species that ranges will need to shift with climate change as populations within current ranges become increasingly vulnerable to decline. Species capable of dispersing beyond their leading edges may be more likely to persist, as our evidence suggests that projected changes in climate may benefit such populations. If species are unable to disperse to new habitat on their own, assisted migration may need to be considered to prevent the widespread loss of vulnerable species. [ABSTRACT FROM AUTHOR]

Fungal endophytes are a ubiquitous feature of plants, yet for many fungi the benefits of endophytism are still unknown. The Foraging Ascomycete (FA) hypothesis proposes that saprotrophic fungi can utilize leaves both as dispersal vehicles and as resource havens during times of scarcity. The presence of saprotrophs in leaf endophyte communities has been previously observed but their ability to transfer to non-foliar saprobic substrates has not been well investigated. To assess this ability, we conducted a culture study by placing surface-sterilized leaves from a single tropical angiosperm tree (Nectandra lineatifolia) directly onto sterile wood fragments and incubating them for 6 weeks. Fungi from the wood were subsequently isolated in culture and identified to the genus level by ITS sequences or morphology. Four-hundred and seventy-seven fungal isolates comprising 24 taxa were cultured from the wood. Of these, 70.8% of taxa (82.3% of isolates) belong to saprotrophic genera according to the FUNGuild database. Furthermore, 27% of OTUs (6% of isolates) were basidiomycetes, an unusually high proportion compared to typical endophyte communities. Xylaria flabelliformis, although absent in our original isolations, formed anamorphic fruiting structures on the woody substrates. We introduce the term viaphyte (literally, "by way of plant") to refer to fungi that undergo an interim stage as leaf endophytes and, after leaf senescence, colonize other woody substrates via hyphal growth. Our results support the FA hypothesis and suggest that viaphytism may play a significant role in fungal dispersal. [ABSTRACT FROM AUTHOR]

1. Dracula orchids mimic mushrooms in appearance and scent, and are pollinated by mushroom flies. This study examined the guilds of insect visitors to Dracula species and to co‐occurring mushrooms in an Ecuadorean cloud forest. Significant visitor overlap was documented (mostly in the genera Zygothrica and Hirtodrosophila; Drosophilidae). To test the brood‐site mimicry hypothesis, behavioural observations were also performed and rearing success was examined. 2. Many fly species that visit Dracula are also found on mushrooms. Furthermore, the presence of pollinia enabled us to document the fact that particular individuals visiting mushrooms also visit Dracula. Roughly two‐thirds of the visitors to these unusual flowers are fungal‐associated, and the rest appear to be Dracula specialists. 3. A variety of behaviours common on both host groups were observed, including courtship semaphoring, feeding, sheltering, defending territory, and mating. Given this suite of shared reproductive behaviour, it was hypothesised that flies may also oviposit in both substrates. Flies were reared from mushrooms, Dracula spp., and other flowers (controls) to determine which substrate led to the highest fitness for the flies. Very few flies emerged from the Dracula flowers and there was no species overlap between the emergent insects and the known pollinators. 4. Despite the fact that there is evidence for brood‐site mimicry, the Dracula situation is complex. All the flies could derive many of the same fitness benefits from the flowers as they do from mushrooms (shelter, food, mating), but they are clearly not gaining the same fitness benefit, in terms of progeny, on flowers compared with mushrooms. [ABSTRACT FROM AUTHOR]

Plant phenology will likely shift with climate change, but how temperature and/or moisture regimes will control phenological responses is not well understood. This is particularly true in Mediterranean climate ecosystems where the warmest temperatures and greatest moisture availability are seasonally asynchronous. We examined plant phenological responses at both the population and community levels to four climate treatments (control, warming, drought, and warming plus additional precipitation) embedded within three prairies across a 520 km latitudinal Mediterranean climate gradient within the Pacific Northwest, USA. At the population level, we monitored flowering and abundances in spring 2017 of eight range‐restricted focal species planted both within and north of their current ranges. At the community level, we used normalized difference vegetation index (NDVI) measured from fall 2016 to summer 2018 to estimate peak live biomass, senescence, seasonal patterns, and growing season length. We found that warming exerted a stronger control than our moisture manipulations on phenology at both the population and community levels. Warming advanced flowering regardless of whether a species was within or beyond its current range. Importantly, many of our focal species had low abundances, particularly in the south, suggesting that establishment, in addition to phenological shifts, may be a strong constraint on their future viability. At the community level, warming advanced the date of peak biomass regardless of site or year. The date of senescence advanced regardless of year for the southern and central sites but only in 2018 for the northern site. Growing season length contracted due to warming at the southern and central sites (~3 weeks) but was unaffected at the northern site. Our results emphasize that future temperature changes may exert strong influence on the timing of a variety of plant phenological events, especially those events that occur when temperature is most limiting, even in seasonally water‐limited Mediterranean ecosystems. [ABSTRACT FROM AUTHOR]

Wetlands are the major natural source of the greenhouse gas methane (CH4) and are also potentially an important source of nitrous oxide (N2O), though there is considerable variability among wetland types with some of the greatest uncertainty in freshwater mineral-soil wetlands. In particular, trace gas emissions from seasonal wetlands have been very poorly studied. We measured fluxes of CH4, N2O, and CO2 (carbon dioxide), soil nutrients, and net primary productivity over one year in natural, restored, and agricultural seasonal wetland prairies in the Willamette Valley, Oregon, USA. We found zero fluxes for CH4 and N2O, even during periods of extended waterlogging of the soil. To explore this lack of emissions, we performed a laboratory experiment to examine the controls over these gases. In a fully-factorial design, we amended anaerobic soils from all wetlands with nitrate, glucose, and NaOH (to neutralize pH) and measured production potentials of N2, N2O, CH4, and CO2. We found that denitrification and N2O production were co-limited by nitrate and carbon, with little difference between the three wetland types. This co-limitation suggests that low soil carbon availability will continue to constrainN2Oemissions and denitrification in these systems even when receiving relatively high levels of nitrogen inputs. Contrary to the results for N2O, the amended wetland soils never produced significant amounts of CH4 under any treatment. We hypothesize that high concentrations of alternative electron acceptors exist in these soils so that methanogens are noncompetitive with other microbial groups. As a result, these wetlands do not appear to be a significant source or sink of soil carbon and thus have a near zero climate forcing effect. Future research should focus on determining if this is a generalizable result in other seasonal wetlands. [ABSTRACT FROM AUTHOR]

Flowers use olfactory and visual signals to communicate with pollinators. Disentangling the relative contributions and potential synergies between signals remains a challenge. Understanding the perceptual biases exploited by floral mimicry illuminates the evolution of these signals. Here, we disentangle the olfactory and visual components of Dracula lafleurii, which mimics mushrooms in size, shape, color and scent, and is pollinated by mushroom-associated flies., To decouple signals, we used three-dimensional printing to produce realistic artificial flower molds that were color matched and cast using scent-free surgical silicone, to which we could add scent. We used GC- MS to measure scents in co-occurring mushrooms, and related orchids, and used these scents in field experiments., By combining silicone flower parts with real floral organs, we created chimeras that identified the mushroom-like labellum as a source of volatile attraction. In addition, we showed remarkable overlap in the volatile chemistry between D. lafleurii and co-occurring mushrooms., The characters defining the genus Dracula - a mushroom-like, 'gilled' labellum and a showy, patterned calyx - enhance pollinator attraction by exploiting the visual and chemosensory perceptual biases of drosophilid flies. Our techniques for the manipulation of complex traits in a nonmodel system not conducive to gene silencing or selective breeding are useful for other systems. [ABSTRACT FROM AUTHOR]

Many hypotheses address the associations of plant community composition with natural enemies, including: (i) plant species diversity may reduce enemy attack, (ii) attack may increase as host abundance increases, (iii) enemy spillover may lead to increased attack on one host species due to transmission from another host species, or enemy dilution may lead to reduced attack on a host that would otherwise have more attack, (iv) physical characteristics of the plant community may influence attack, and (v) plant vigor may affect attack. Restoration experiments with replicated plant communities provide an exceptional opportunity to explore these hypotheses. To explore the relative predictive strengths of these related hypotheses and to investigate the potential effect of several restoration site preparation techniques, we surveyed arthropod herbivore and fungal pathogen attack on the six most common native plant species in a restoration experiment. Multi-model inference revealed a weak but consistent negative correlation with pathogen attack and host diversity across the plant community, and no correlation between herbivory and host diversity. Our analyses also revealed host species-specific relationships between attack and abundance of the target host species, other native plant species, introduced plant species, and physical community characteristics. We found no relationship between enemy attack and plant vigor. We found minimal differences in plant community composition among several diverse site preparation techniques, and limited effects of site preparation techniques on attack. The strongest associations of community characteristics with attack varied among plant species with no community-wide patterns, suggesting that no single hypothesis successfully predicts the dominant community-wide trends in enemy attack. [ABSTRACT FROM AUTHOR]

Parasite damage strongly affects dynamics of boreal forests. Damage levels may be affected by climate change, either directly or indirectly through changes in properties of host trees. We examined how herbivore and pathogen damage in Alnus viridis subsp. fruticosa (Rupr.) Nym. depend on leaf morphology and chemistry, tree size, and tree neighborhood. Damage and tree properties were measured in 2003 and 2004 on eight trees at each of 20 sites in Interior Alaska. Damage varied significantly among sites and among trees within sites, but Cartesian distances between sites were not correlated with similarity in damage levels. Compared with middle leaves, terminal leaves experienced less damage from phloem-feeding insects and pathogens, whereas leaf-roller damage was largely confined to terminal leaves. Summer drought in 2004 strongly reduced damage from phloem-feeding insects, while damage from chewing insects increased. Overall, herbivore damage was best explained by leaf morphology and chemistry, and pathogen damage by the proximity of other trees; the two damage types were not correlated with each other. Reproduction was negatively correlated with herbivore damage, but positively with pathogen damage. The contrasting relationships found for individual feeding guilds suggest that they must be studied separately in assessing impacts of climate change on parasite damage. [ABSTRACT FROM AUTHOR]

Premise Methods Results Conclusions Understanding how population dynamics vary in space and time is critical for understanding the basic life history and conservation needs of a species, especially for narrow endemic species whose populations are often in similar environments and therefore at increased risk of extinction under climate change. Here, we investigated the spatial and temporal variation in population dynamics of Ranunculus austro‐oreganus, a perennial buttercup endemic to fragmented prairie habitat in one county in southern Oregon.We performed demographic surveys of three populations of R. austro‐oreganus over 4 years (2015–2018). We used size‐structured population models and life table response experiments to investigate vital rates driving spatiotemporal variation in population growth.Overall, R. austro‐oreganus had positive or stable stochastic population growth rates, though individual vital rates and overall population growth varied substantially among sites and years. All populations had their greatest growth in the same year, suggesting potential synchrony associated with climate conditions. Differences in survival contributed most to spatial variation in population growth, while differences in reproduction contributed most to temporal variation in population growth.Populations of this extremely narrow endemic appear stable, with positive growth during our study window. These results suggest that populations of R. austro‐oreganus are able to persist if their habitat is not eliminated by land‐use change. Nonetheless, its narrow distribution and synchronous population dynamics suggest the need for continued monitoring, particularly with ongoing habitat loss and climate change. [ABSTRACT FROM AUTHOR]

Phenology—recurring seasonal events in an organism's life cycle—is largely driven by local climates <1 km2 (microclimates), and changes in phenology are frequently used to indicate a species' or community response to climate change. Phenological shifts can result in trophic asynchrony, population declines of higher‐level consumers, and reduction of plant fitness. While timing of phenological events is often correlated with elevation, studies have shown that microclimates created by areas of heterogeneous topography can be decoupled from regional climate patterns and that the distribution of microclimates does not always follow the elevation gradient. To examine the interaction between regional weather patterns and microclimate, and the subsequent effect of microclimate on phenology, we conducted standardized weekly spring phenology surveys of 18 native forest plants at the H.J. Andrews Experimental Forest in the Western Cascades from 2009 to 2016. We saw a high degree of inter‐annual variability of microclimate within and across sites, resulting in a changing pattern of microclimate diversity across the landscape from year to year. Most importantly, we saw that years with regional conditions predicted by continued climate change showed a loss of diversity in both microclimate and phenological events, with a more rapid advancement in bud break occurring at higher elevation sites. This study highlights the importance of understanding the interactions between regional and local processes that determine microclimate conditions and how those conditions influence patterns of plant phenology within forest communities, across mountain landscapes and over time, with implications for the capacity of mountainous regions to buffer local communities against the effects of climate change. [ABSTRACT FROM AUTHOR]

Ecuador has among the world's highest biodiversity, despite being a tiny fraction of the world's land area. The threat of extinction for some of this biodiversity has dramatically increased since April 2016, during which time the Ecuadorian government has opened around 13% of the country to mining exploration, with many of the concessions in previously protected forests. Herein, we describe the system of protected lands in Ecuador, their mining laws, and outline the scale of threat by comparing the mammals, amphibians, reptiles, birds, and orchids from several now threatened protected areas, classed as "Bosques Protectores," in the northwestern montane cloud forests. Together, these reserves form a buffer and a southern corridor for the still-protected Cotacachi-Cayapas Ecological Reserve, which is otherwise now surrounded by mining concessions. We gathered published literature, "gray literature," information from reserve records and websites, and our previously unpublished observations to make comparative species tables for each reserve. Our results reveal the potential losses that mining could cause: eight critically endangered species, including two primates (brown-headed spider monkey and white-fronted capuchin), 37 endangered species, 153 vulnerable, 89 near threatened, and a large number of less threatened species. Our data show that each reserve protects a unique subset of taxa in this region of highly localized endemics and the reserves also generate sustainable income for local people. The short-term national profits from mining will not compensate for the permanent biodiversity losses, and the long-term ecosystem service and economic losses at the local and regional level. [ABSTRACT FROM AUTHOR]