Forest elephant crop depredation incidents (CDIs) threaten both villagers' livelihoods and conservation efforts for endangered forest elephants in countries such as Gabon, Africa. We argue that improving crop protection alone will not solve the problem. Rather, CDIs will continue to escalate unless both villagers' and elephants' needs are mutually satisfied so as to create conditions for coexistence. For that reason, we developed a landscape framework for human-elephant coexistence to support collaborative planning at village and landscape scales by addressing both human and elephant needs. To this end, we interviewed villagers and conservation professionals, and searched the literature to identify actions to mitigate each of five previously identified CDI problem types that were derived from stakeholder interviews. These actions were synthesized to formulate five overarching coexistence strategies and detailed objectives that address unmet human or elephant needs underlying each problem type. The resulting landscape coexistence framework comprises a transferable structure with three goals: supporting elephants, supporting villagers, and differentiating their territories. Coexistence strategies are nested under goals, and objectives under strategies. The accompanying action toolbox organizes the 60 actions under the strategies and objectives, with sources for each action. The framework and toolbox are designed for use in collaborative planning forums to address a broad suite of spatially situated processes that interact to increase CDIs.

Fire is a key disturbance process that shapes the structure and function of montane temperate rainforest in the Pacific Northwest (PNW). Recent research is revealing more frequent historical fire activity in the western central Cascades than expected by conventional theory. Indigenous peoples have lived in the PNW for millennia. However, Indigenous people's roles in shaping vegetation mosaics in montane temperate forests of the PNW has been overlooked, despite archaeological evidence of long-term, continuous human use of these landscapes. In this paper, we present a generalizable research framework for overcoming biases often inherent in historical fire research. The framework centers Indigenous perspectives and ethnohistory, leveraging theory in human ecology and archaeology to interpret fire histories. We apply this framework to place-based, empirical evidence of Indigenous land use and dendroecological fire history. Our framework leads us to conclude that the most parsimonious explanation for the occurrence of historical high fire frequency in the western Cascades is Indigenous fire stewardship. Further, our case study makes apparent that scholars can no longer ignore the role of Indigenous people in driving montane forest dynamics in the PNW.

Premise: 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. Methods: 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. Results: 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. Conclusions: 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.

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.

Stanford Synchrotron Radiation Lightsource serves a wide scientific community with its variety of X-ray capabilities. Recently, a wiggler X-ray source located at beamline 10-2 has been employed to perform high-resolution rocking curve imaging (RCI) of diamond and silicon crystals. X-ray RCI is invaluable for the development of upcoming cavity-based X-ray sources at SLAC, including the cavity-based X-ray free-electron laser and X-ray laser oscillator. In this paper, the RCI apparatus is described and experimental results are provided to validate its design. Future improvements of the setup are also discussed.

Forest elephant crop depredation incidents (CDIs) around Gabon’s national parks threaten both villagers’ livelihoods and conservation efforts for critically endangered forest elephants. Most CDI-mitigation efforts have focused on improving crop protection. We argue that conflicts will continue to escalate unless broader villager and elephant needs are addressed simultaneously. For that reason, we investigated the factors contributing to CDIs as a first step toward mitigating conflict by fostering coexistence. We compiled perceptions of 24 villagers and 22 conservation professionals at Lopé National Park in Gabon using semi-structured interviews, allowing participants to create individual narratives. We analyzed the narratives through content analysis, categorizing CDI perceptions into four connected _themes_ to build a synthetic framework based on three landscape _contexts_ across which six socioecological _drivers_ fostered five landscape _dynamics_ that led to five proximal _problem types_ leading directly to CDIs. Two problem types were centered on ineffective crop protection methods and socioeconomic changes that have intensified rural exodus. The other two were centered on unmet elephant needs pushing them to seek crops. The fifth type, regular human-elephant negative interactions, resulted from increasing land use overlap by both villagers and elephants. Villagers framed the CDI problem primarily through their experiences of conflict in village areas. Professionals likewise saw the importance of direct conflict in village areas but also identified a broader suite of factors, including conservation policies, logging, and declining native fruit production pushing elephants toward villages in search of food and a safe environment. Common to both stakeholders’ narratives was the perception that increased spatial and temporal overlap was the greatest contributor to increasing CDIs. Points of agreement, such as those around regular human-elephant negative interactions and ineffective crop protection, may provide opportunities to build trust and prioritize initial interventions. Differences in perspectives should be investigated further to seek possible resolutions.

We integrated a mechanistic wildfire simulation system with an agent-based landscape change model to investigate the feedbacks among climate change, population growth, development, landowner decision-making, vegetative succession, and wildfire. Our goal was to develop an adaptable simulation platform for anticipating risk-mitigation tradeoffs in a fire-prone wildland–urban interface (WUI) facing conditions outside the bounds of experience. We describe how five social and ecological system (SES) submodels interact over time and space to generate highly variable alternative futures even within the same scenario as stochastic elements in simulated wildfire, succession, and landowner decisions create large sets of unique, path-dependent futures for analysis. We applied the modeling system to an 815 km2 study area in western Oregon at a sub-taxlot parcel grain and annual timestep, generating hundreds of alternative futures for 2007–2056 (50 years) to explore how WUI communities facing compound risks from increasing wildfire and expanding periurban development can situate and assess alternative risk management approaches in their localized SES context. The ability to link trends and uncertainties across many futures to processes and events that unfold in individual futures is central to the modeling system. By contrasting selected alternative futures, we illustrate how assessing simulated feedbacks between wildfire and other SES processes can identify tradeoffs and leverage points in fire-prone WUI landscapes. Assessments include a detailed “post-mortem” of a rare, extreme wildfire event, and uncovered, unexpected stabilizing feedbacks from treatment costs that reduced the effectiveness of agent responses to signs of increasing risk.

Background The natural removal of carbon dioxide (CO2) from the atmosphere through land conservation, restoration, and management is receiving increasing attention as a scalable approach for climate change mitigation. However, different land-use sectors compete for resources and incentives within and across geopolitical regions, resulting in divergent goals and inefficient prioritization of CO2 removal efforts. Thus, a unifying framework is needed to accelerate basic research and coordinated interventions to accelerate climate change mitigation. Scope We propose a generalizable framework for Enhanced Natural Climate Solutions (NCS +), which we define as activities that can be coordinated to increase carbon drawdown and permanence on land while improving livelihoods and the provision of natural resources in vulnerable communities and ecosystems. The framework builds on interdisciplinary scientific convergence, including critical socioecological interactions, to inform both top-down policy incentives and bottom-up adoption by industries and managers. To achieve this goal, we suggest a multi-tiered approach for the prioritization of projects at local to regional scales that would simultaneously accelerate scientific discovery and broad implementation of CO2 removal projects. Conclusions Our vision leverages input from hundreds of researchers and land managers, including social and environmental scientists as well as representatives from tribal governments, state, and federal agencies in the Pacific Northwest of the USA, as a model system. Five guiding principles orient the framework which would be applicable in any region. As evidence of feasibility, we provide a synthesis of interdisciplinary studies that illustrate how coordinated action, with explicit consideration of system-specific technical and socioecological limitations, can lead to scalable projects with multiple co-benefits. Using theory as a linchpin for innovation, we propose that NCS + could better align climate change mitigation, adaptation, and justice goals at multiple scales.

Net primary productivity (NPP) is a key ecosystem function of plant communities. Climate change is expected to affect NPP both directly and indirectly through associated edaphic and plant community factors. Changes in soil nutrients, plant species richness and/or functional group dominance may amplify or counteract direct climatic effects on NPP, and responses may differ above-versus belowground, making it challenging to predict the net effects on NPP. In this study, we manipulated temperature and precipitation at four sites spanning a latitudinal Mediterranean-climate gradient in the Pacific Northwest, USA, and measured aboveground, belowground, and total NPP responses in experimentally assembled prairie plant communities. Using structural equation models, we disentangled the direct effects of climate from its indirect effects through soil nutrient availability and plant community responses. We found that warming, primarily by reducing soil moisture (that is, drying), had a net negative effect on all aspects of NPP, but these negative effects were partially ameliorated by increasing nitrogen and phosphorus availability, as well as changes to the plant community. Specifically, warming, drying, and greater nutrient availability caused species richness to decline, leading to greater dominance by a restricted set of functional groups, which positively affected aboveground NPP. Furthermore, a shift from perennial grass to annual grass dominance increased the ratio of aboveground to belowground NPP. Our results demonstrate that the indirect effects of climate change can help partially buffer the negative direct effects on NPP in Mediterranean-climate prairies. However, increasing soil moisture limitation may still overwhelm the positive effects of such intermediary pathways.

Private landowners in the southern Willamette Valley of Oregon, USA were surveyed. The survey queried probabilities of implementing specific fuels reduction projects in extensive areas of specific forest types on their property. The projects were described in relation to the beginning and target forest types, the actions required, costs, and long-term maintenance. Forest types were first rated for scenic beauty and informed levels of wildfire risk reduction, scarce habitat production, and associated property rights risks. Propensities to perform each fuels reduction project were then obtained. These were adversely affected by disbelief in heightened wildfire risks or climate change, higher project costs, feelings of hopeless vulnerability to wildfire, and low aesthetic affections for target forests. Propensities were enhanced by aesthetic affection for target forests, belief in the efficaciousness of fuels reduction, previous experience with wildfire evacuation, and higher incomes. All landowners favored thinning of young conifer forests, but some were averse to thinning of mature conifer forests. Anthropocentric landowners, mainly farmers, foresters, and some small holders, tended to favor conventional thinnings toward commercially valuable conifer forests and avoided long-term habitat maintenance. Nature-centric landowners, mainly some rural residents and wealthy estate owners, leaned more toward long term habitat goals and oak forests.

Aim How climate change will alter plant functional group composition is a critical question given the well-recognized effects of plant functional groups on ecosystem services. While climate can have direct effects on different functional groups, indirect effects mediated through changes in biotic interactions have the potential to amplify or counteract direct climatic effects. As a result, identifying the underlying causes for climate effects on plant communities is important to conservation and restoration initiatives. Location Western Pacific Northwest (Oregon and Washington), USA. Methods Utilizing a 3-year experiment in three prairie sites across a 520-km latitudinal climate gradient, we manipulated temperature and precipitation and recorded plant cover at the peak of each growing season. We used structural equation models to examine how abiotic drivers (i.e. temperature, moisture and soil nitrogen) controlled functional group cover, and how these groups in turn determined overall plant diversity. Results Warming increased the cover of introduced annual species, causing subsequent declines in other functional groups and diversity. While we found direct effects of temperature and moisture on extant vegetation (i.e. native annuals, native perennials and introduced perennials), these effects were typically amplified by introduced annuals. Competition for moisture and light or space, rather than nitrogen, were critical mechanisms of community change in this seasonally water-limited Mediterranean-climate system. Diversity declines were driven by reductions in native annual cover and increasing dominance by introduced annuals. Main conclusions A shift towards increasing introduced annual dominance in this system may be akin to that previously experienced in California grasslands, resulting in the "Californication" of Pacific Northwest prairies. Such a phenomenon may challenge local land managers in their efforts to maintain species-rich and functionally diverse prairie ecosystems in the future.

Stanford Synchrotron Radiation Lightsource (SSRL) serves a wide scientific community with its variety of X-ray capabilities. Recently, we have employed a wiggler source located at beamline 10-2 to perform high resolution rocking curve imaging (RCI) of diamond and silicon crystals. Inhouse X-ray RCI capability is important for the upcoming cavity-based X-ray source development projects at SLAC, such as cavity-based XFEL (CBXFEL) and X-ray laser oscillator (XLO). In this proceeding, we describe theoretical considerations, and provide experimental results, validating the design of our apparatus. We also provide a plan for future improvements of the RCI@SSRL program.

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.

With ongoing climate change, populations are expected to exhibit shifts in demographic performance that will alter where a species can persist. This presents unique challenges for managing plant populations and may require ongoing interventions, including in situ management or introduction into new locations. However, few studies have examined how climate change may affect plant demographic performance for a suite of species, or how effective management actions could be in mitigating climate change effects. Over the course of two experiments spanning 6 yr and four sites across a latitudinal gradient in the Pacific Northwest, United States, we manipulated temperature, precipitation, and disturbance intensity, and quantified effects on the demography of eight native annual prairie species. Each year we planted seeds and monitored germination, survival, and reproduction. We found that disturbance strongly influenced demographic performance and that seven of the eight species had increasingly poor performance with warmer conditions. Across species and sites, we observed 11% recruitment (the proportion of seeds planted that survived to reproduction) following high disturbance, but just 3.9% and 2.3% under intermediate and low disturbance, respectively. Moreover, mean seed production following high disturbance was often more than tenfold greater than under intermediate and low disturbance. Importantly, most species exhibited precipitous declines in their population growth rates (λ) under warmer-than-ambient experimental conditions and may require more frequent disturbance intervention to sustain populations. Aristida oligantha, a C4 grass, was the only species to have λ increase with warmer conditions. These results suggest that rising temperatures may cause many native annual plant species to decline, highlighting the urgency for adaptive management practices that facilitate their restoration or introduction to newly suitable locations. Frequent and intense disturbances are critical to reduce competitors and promote native annuals' persistence, but even such efforts may prove futile under future climate regimes.

Earth and Space Science Open Archive PosterOpen AccessYou are viewing the latest version by default [v1]Seasonal Effects of Experimental Warming on Soil Biogeochemistry and Plant Functional Diversity in Pacific Northwest PrairiesAuthorsBarbaraBomfimiDHilary RoseDawsoniDLucasSilvaiDBrendanBohannanScottBridghamPaulReedGrahamBailesBartJohnsonLaurelPfeifer-MeisterSee all authors Barbara BomfimiDCorresponding Author• Submitting AuthorUniversity of OregoniDhttps://orcid.org/0000-0001-9510-2496view email addressThe email was not providedcopy email addressHilary Rose DawsoniDUniversity of Oregon, EugeneiDhttps://orcid.org/0000-0003-4613-762Xview email addressThe email was not providedcopy email addressLucas SilvaiDUniversity of OregonEugeneiDhttps://orcid.org/0000-0002-4838-327Xview email addressThe email was not providedcopy email addressBrendan BohannanUniversity of OregonEugeneview email addressThe email was not providedcopy email addressScott BridghamUniversity of OregonEugeneview email addressThe email was not providedcopy email addressPaul ReedUniversity of OregonEugeneview email addressThe email was not providedcopy email addressGraham BailesUniversity of Oregonview email addressThe email was not providedcopy email addressBart JohnsonUniversity of OregonEugeneview email addressThe email was not providedcopy email addressLaurel Pfeifer-MeisterUniversity of OregonEugeneview email addressThe email was not providedcopy email address

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.

Exposure to biodiverse environments such as forests can benefit human well-being, and evidence suggests exposure to high microbial diversity may improve mental and immune health. However, the factors that drive microbial community assembly are poorly understood, as is the relationship between exposure to these communities and human health. We characterized airborne bacterial communities in two disparate types of urban greenspace (forest and grass) in late-spring 2017 at sites previously sampled in late-summer 2015 in Eugene-Springfield, Oregon, using high-throughput metabarcode sequencing. While all sites shared a core aerobiome in late-spring consisting of plant- and soil-associated genera, forests had significantly higher diversity than grass sites (F = 12, P = 0.004). Vegetation type explained 14% of the difference between forest and grass aerobiomes, yet individual site location explained 41% of the variation. These results were similar to but amplified over those from late summer, suggesting that both aerobiome diversity and vegetation-driven effects are higher when deciduous foliage is fresher and more active, temperatures cooler, and humidity higher. Continued exploration and hypothesis-driven research will enable development of mechanistic theory describing key drivers of urban aerobiome assembly and its relationship to human health, which, in turn, will help urban designers and planners create evidence-based salutogenic cities for future generations.

Interactions between climate change and urbanization may affect stream ecosystems in unexpected ways. With an integrated modelling framework, we assessed the combined hydrological impacts of climate change and urbanization under historical and future climate regimes across varied development scenarios in three watersheds in the Willamette Valley, Oregon. First, through an agent-based land use change model Envision, we created four development scenarios that consisted of 2 x 2 combinations of regional growth (compact population growth in urban cores vs. dispersed growth into rural areas) and stormwater management scenarios (with vs. without integrated stormwater management, ISM). ISM was defined as the integration of strategic organization of land uses with site-scale stormwater best management practices. Next, two future climate regimes were developed by statistically downscaling projections from two general circulation models (CanESM2 and CNRM-CM5) that performed well in replicating historical climate. The hydrological assessment of these scenarios was then conducted with the Soil and Water Assessment Tool. Using 10 ecologically significant flow metrics, we evaluated each scenario based on the magnitude of change in each metric and the degree to which such changes could be mitigated. Climate change alone led to a drying trend in flow regimes under both future climates. Combined with urbanization, it magnified changes in six of 10 metrics but attenuated impacts for three other measures of flashiness in at least one basin. The combination of compact growth and ISM effectively mitigated alterations for seven (out of nine) metrics sensitive to the combined impacts in at least one basin, with ISM being more effective than compact growth. The modelling framework teased out both nuanced differences and generalizable trends in hydrological impacts of urbanization and climate change and offers key methodological innovations towards an integrated framework capable of linking landscape planning mechanisms with the goal of sustaining stream ecosystem health.

Greater exposure to environmental microorganisms has been hypothesized to reduce the likelihood of developing autoimmune disorders, and vegetation is known to be a source of diverse microbiota to the air. However, the spatiotemporal dynamics of airborne microbial communities in urban environments with varying amounts and types of vegetation are poorly understood. In this study we used high-throughput sequencing of the bacterial 16S rRNA gene to assess whether fine-scale variation in urban vegetation influences the diversity, composition, or structure of airborne bacterial communities over time. We used passive settling dishes to collect airborne bacteria from 36 sites representing three urban land cover types (forest, grassland, paved) over a 3-month period in Eugene-Springfield, Oregon, USA. We used remote sensing data (aerial 4-band orthoimagery and LiDAR) and geographic information systems (GIS) to assess detailed site characteristics (e.g., total vegetation cover and structural diversity) for each site. Our initial analysis indicated that site was the most important factor explaining variation in bacterial community structure (R2 = 0.32, p < 0.001), followed by sampling date (R2 = 0.24, p < 0.001), while land cover type was a significant but weak predictor (R2 = 0.06, p < 0.001) and other vegetation metrics were even less predictive. However, when samples were analyzed separately by date, the explanatory power of land cover type increased substantially; six of nine dates showed significant effects (p < 0.05) with R2 ranging from 0.16–0.31, indicating that land cover type had a marked influence on bacterial community structure that was obscured by the effects of site and sampling date. Despite the importance of site as a predictor of bacterial community structure, Mantel tests for spatial correlation were insignificant for most sampling dates, suggesting that localized site characteristics were driving this relationship. We use our results to propose a space-time conceptual model of the interactions between site-scale environmental features (e.g., vegetation characteristics) and regional-scale temporal processes and events (e.g., agricultural harvesting) to understand and perhaps manage intraurban airborne bacterial communities.

Abstract 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.