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Negative health impacts of water insecurity are often felt most in poor and rural communities and communities of color, who are more likely to be underserved by water infrastructure and disproportionately subject to socioeconomic stressors. Despite mandated efforts to allocate significant federal resources to infrastructure funding in ‘disadvantaged communities,’ communities with the most need risk systematic exclusion from access to resources, decision-making structures, and even benefits of research intended to address inequitable infrastructure services and health outcomes in their own communities. This project aims to describe groundwork and preliminary findings from community-engaged environmental research conducted within an ongoing community-based participatory research partnership in Robeson County, NC, a majority–minority county with the lowest median household income of NC’s 100 counties. Semi-structured interviews conducted with community members were analyzed to identify concerns about drinking water security (including safety, affordability, and reliability), perceptions of water quality, averting behaviors taken due to water insecurity, and ideas for improving water security. Findings suggest that there is a high level of mistrust in community water supplies, with perceptions of poor water quality driving a reliance on bottled water. Those relying on private wells expressed greater trust in their water and lower reliance on bottled water. Concerns about affordability were less prominent than those about water quality. Insufficient water reliability (low flow) was mentioned by many respondents, including those with community water service and those relying on private wells. Most supported increasing taxes to improve water security and also recommended increasing communications between water service providers and the public to improve trust. Overall, this work suggests the need for a comprehensive assessment of the quality and reliability of community water services in Robeson County, interventions to address problems identified, and much more engagement with the community about identifying and allocating funding to solve water security problems.

High-elevation rock outcrop ecosystems are home to a unique flora, with endemic and disjunct species hypothesized to be susceptible to shifts in species composition or phenology with climate warming. Easily accessed outcrops also are susceptible to human disturbance. We surveyed vegetation, flowering plant species, and insect pollinators on seven outcrops that range from relatively inaccessible to frequently visited to determine if: (1) vegetation composition or abundance correlates with accessibility; (2) establish baseline information on species composition and abundance; and (3) determine if specialized plant-pollinator interactions indicate susceptibility to shifts in flowering time. Richness of plant cover was not related to outcrop accessibility; however, the least accessible outcrop had the lowest frequency of bare rock, relatively high lichen cover, and vegetation patches with a distinct flora of spikemoss (Selaginella sp.), mosses, lichens, and vascular plants. Bare rock was most abundant on the most accessible outcrop. Almost half of obligate outcrop plant species within sampled vegetation occurred on only one or two of the seven outcrops. Each outcrop had a unique subset of species in flower at each sampling time. Flowering plants were visited, on average, by five different insect morpho-species and families. Each insect morpho-species visited at least two plant species; bumblebees (Bombus) and sweatbees (Halictidae) visited as many as eight plant species. Generalist interactions suggest lower susceptibility to temporal mismatches between plants and pollinators with climate warming; however, individual outcrops do not harbor the full suite of specialized and sensitive plant species, and conservation efforts should focus on retaining outcrop plant communities.

AIM: To test the Canopy Cover (CaCo) index for forest vegetation research estimation of canopy cover from hemispherical photographs, and introduce a new Android smartphone application for use of this index. METHODS: The original and modified CaCo index were evaluated using a data set of 234 hemispherical photographs taken in 78 plots in coniferous, mixed and broad‐leaved deciduous forests. The results of the CaCo analysis of these photographs were compared with expert field visual estimation of canopy cover of these plots. For each hemispherical photograph, several CaCo values were calculated based on the photograph being restricted to different degrees by artificial horizon masking. The CaCo index was also tested with respect to precision of canopy cover estimation and sensitivity to different photographic equipment, using a different set of 93 canopy photographs taken in mixed and coniferous forests. Calculation of the CaCo index was done with the newly developed GLAMA – Gap Light Analysis Mobile Application software. RESULTS: Linear regression showed a close relationship between the CaCo index and visually observed canopy cover data. A proposed calculation modification improved the stability of the CaCo index in cases in which no horizon masking was applied. The best fit, zero‐intercept and a regression slope close to1 were found in cases in which an artificial horizon mask that extended higher than 45° restricted the bottom part of the sky hemisphere. Low sensitivity of the CaCo index to type of photographic equipment used was shown. CONCLUSIONS: The CaCo index is robust and can be used for precise canopy cover estimation, comparable to visual canopy cover estimation and unaffected by observer bias. Not only can it be used on already‐captured photographs, but the index can also be employed on smartphones to rapidly capture hemispherical photographs and immediately calculate their index values. This application is freely available on the Internet and can serve as a powerful research and educational tool that can not only calculate CaCo values, but also standardize forest canopy visual estimates.

Aims: Structural and compositional changes along post-fire succession modify plant community proneness to burn (flammability). The dominant regeneration strategies and life forms, and their interactions along post-fire succession, modulate these changes by affecting density, amount and connectivity of fuels. Depending on how flammability evolves during post-fire succession it may feed back negatively, neutrally or positively into fire probability and behaviour. Negative fire-vegetation feedbacks arise when communities increase flammability as stands age, while positive feedbacks occur where early stages have higher flammability than later stages. We characterized changes in vegetation structure and fuel characteristics with time since fire in sites where either resprouters maintained dominance (shrublands), or where colonizer trees reached the sites and dominate later post-fire stages (forests). Location: Northwestern Patagonia, Argentina. Methods: We measured vegetation structure and characterized fine fuels with the intercept pole method in stands of different post-fire age in 18 shrublands (range 1–115 years) and 18 forests (range 7–216 years). Results: In shrublands fuel amount quickly recovered after fire to a relatively constant value and fine fuel density remained high. Conversely, in forests, fuel amount rapidly increased during early post-fire stages (when resprouting shrubs dominate the community), peaked at c. 30–50 years (related to the co-existence of resprouters and young trees) and decreased to a relatively constant value (when tall trees dominate the community and suppress resprouters). Moreover, forest fuel density decreased with time. These changes in fuel characteristics were largely linked to changes in vegetation structure, which in turn were modulated by the dominant regeneration strategies and life forms. Conclusions: Our results provide evidence of a positive fire–vegetation feedback for the community dominated by colonizer trees, while the community dominated by resprouter shrubs showed a neutral feedback. Given the co-existence of flammable shrublands bordering fire-sensitive forests and their low tree regeneration rates, we argue that forest communities are especially sensitive to changes in fire frequency and severity driven by global change. Anthropogenic or climate-driven changes in ignitions are threatening these landscapes, which may undergo potentially rapid transformations, as seen in other temperate ecosystems.

This volume presents the first full-scale biography of Daniel Jones, a preeminent scholar and leading British phonetician of the early twentieth century, and the first linguist to hold a chair at a British university. This book, richly illustrated with partly unpublished material traces Jones's life and career, including his contacts with other linguists, and with figures outside the linguistic world notably Robert Bridges and George Bernard Shaw.

Question It is debated whether forest understory communities will be sensitive to projected climate change or inert due to the regulating effect of local site conditions and soil parameters. A distinction between the relative importance of climate or soil is often hardly possible because both factors usually change at different spatial scales in forests. Here, we compare the relative influence of climate and soil on the forest understory vegetation in lowland beech forest ecosystems (Fagus sylvatica), which were selected for their ecological homogeneity. Location Nine sites along a strong temperature gradient (ΔT = 4 K from east to west in winter, south to north in summer) between Rostock (Germany) and Gdańsk (Poland) in a Baltic Quaternary ground moraine landscape. Methods We conducted a vegetation survey in 55 vegetation plots (80 m2 each) across nine forest sites mono‐dominated by European beech and analysed how much variation in understory plant composition is explained by climate and soil parameters. Results Soil explained 32% of the compositional variation of understory vegetation across sites, climate 22%, and their interaction 14%. Topsoil pH, subsoil organic matter content, and subsoil C/N ratio were the most important soil variables; growing season temperature and annual water availability were the most important climatic variables. Conclusion The strong dependence on soil properties could moderate the response of the forest understory vegetation to projected climate change. Forest soil properties, however, also depend on the dominant tree species and the macroclimate. To predict climate change impacts on forest understory vegetation, climate change assessments should consider indirect climate change effects as well as interactions between climate and soil. In European lowland beech forests, soil explained 32% of the compositional variation of understory vegetation across sites, climate 22%, and their interaction 14%. The stronger dependence on soil properties could moderate the response of the forest understory vegetation to projected climate change. Future climate change assessments should also account for interactions between climate and soil.

Aims: The environmental legacies of past land use generally have an important impact on the establishment and persistence of forest understorey plant species in post-agricultural forests. Here we studied how the nature of such environmental limitation changes during the first decades of forest development. Location: Deciduous forest 'Muizenbos', northern Belgium. Methods: Two forest herbs with comparable life-history traits, but contrasting rates of post-agricultural forest colonization (Primula elatior, Geum urbanum) were introduced 18 yr ago. Introduction sites were ancient or post-agricultural forest; seeds or adults were added to permanent plots where the understorey vegetation was initially cleared or left undisturbed. We measured chemical soil conditions and recorded the understorey plant community to characterize the sites. The effects of the treatments (land use, vegetation clearing) were tested on the present-day occurrence and abundance of the introduced species across the plots. We also quantified whether the temporal changes in the total number of individuals per site was different between the two land-use types and consistent within land-use types. Results: Land use had an important effect on soil and vegetation. In post-agricultural forest, the P availabilities were many times higher, the plant community diversity was lower and the competitive species were significantly more abundant compared with ancient forest. The present-day abundance of P. elatior was significantly higher in the ancient forest sites, both for planted and seeded plots, while for G. urbanum land use had no effect. The initial vegetation clearing had a persistent effect on the establishment success of both species. The 18-yr-long time series showed consistent changes in the total population sizes in ancient forest: P. elatior has been expanding and G. urbanum initially increased and then declined over the past decade. In post-agricultural forest, temporal patterns were more divergent and partly related to differences in dominant tree species: differences in acidification rates and changes in insolation caused by canopy dieback have put the populations on new and unforeseen trajectories. Conclusions: The longer the experiment is running, the more the individual sites show separate dynamics. In general, we showed that environmental limitation affects plant colonization at least during the first two decades of secondary forest succession, but also that as the post-agricultural forests develop, the nature of environmental limitation changes.

QUESTION: There are large variations in ecosystem carbon (C) exchange in desert ecosystems; however, few studies have examined the effects of community phenological staging on seasonal variations of ecosystem C exchange. We asked whether factors that control temporal changes in net ecosystem C exchange (NEE) vary with an obvious community transition from spring annuals to summer annuals and perennials in a temperate desert steppe. LOCATION: South margin of the Gurbantunggute Desert, northwestern China. METHODS: Ecosystem C and water exchange were measured regularly using closed static chambers and analysed at daily and seasonal intervals. Soil moisture and temperature, photosynthetically active radiation (PAR) and plant biomass were also investigated. RESULTS: Soil temperature had a dominant influence on C release into the atmosphere from the ecosystem during the snowmelting phase (mid‐March to early April). In the spring annual dominant phase (mid‐April to early June), the diurnal pattern of NEE was consistent with the pattern of PAR. The ecosystem became a weak C resource (0.16 ± 0.03 μmol CO₂ m⁻²·s⁻¹) and NEE was positively correlated with community biomass during this phase. In the summer annual and perennial dominant phase (late June to late September), NEE showed relatively large C release (0.74 ± 0.03 μmol CO₂ m⁻²·s⁻¹) and was negatively correlated with soil temperature. CONCLUSION: Our results indicate that the primary abiotic factor controlling NEE varies throughout the year, and NEE is determined by the interaction of a plant functional group with precipitation and temperature.

Questions: Litter quantity in grasslands is highly affected by disturbance regime and influences seed recruitment of constituent species through different mechanisms. Does litter act as a mechanical barrier to burial of freshly shed seeds, and does seed morphology affect this? How is the fate and mobility of seeds affected by litter compared to that of seeds in the seed bank? Location: Transylvanian Lowland, Romania. Methods: We analysed the seed content of litter and underlying soil collected from six dry grassland sites having different disturbance histories, ranging from sites that are currently grazed to those that have been long abandoned. We related seed content of litter to the litter quantity, seed morphology and the seed content of soil, and the estimated seed production of the above-ground vegetation. Results: Grass litter represented a natural trap for seeds; we identified significant quantities of seeds of a large number of species (37) within litter samples, and there was a mass effect in the seed trapping by litter — higher litter quantities trapped more seeds. As a long-term consequence, we expected that seed bank stores would be gradually depleted in abandoned grassland due to the elimination of seeds by litter, but this was not the case. The higher seed production of the above-ground vegetation in undisturbed sites very probably compensated for seed losses through litter. Seeds retained in the litter were larger, more rounded and had appendages than those in soil. Especially for seeds meeting any of these criteria, litter represents a hazardous medium, since the seeds may fail or have delayed germination. Conclusions: The role of litter as a seed trap is more relevant in grasslands that have not been disturbed for a long time, where litter seed entrapment can exert a selective pressure on certain species, and thus drive community assembly in grasslands.

Questions Peatland ecosystems are a globally important carbon storage that is predicted to turn into a carbon source due to water level drawdown (WLD) associated with climate change. The predictions assume stable plant communities but how realistic is this assumption? If the vegetation is not stable, what are the nature and rate of changes? Location Peatland complex in Southern Finland. Methods We conducted a water level drawdown (WLD of ~10 cm) experiment over 17 years in three peatland types differing in their fertility. On each peatland type, we included an adjacent forestry drained (FD, with water table ca. 40 cm lower than in control) area for comparison. Results Peatland type had a clear impact on the response to WLD: at the ecosystem level, the two minerotrophic fens underwent rapid species turnover, while the vegetation in nutrient‐poor bog was more resilient to change. In nutrient‐rich sites, WLD initiated tree canopy development and created understorey conditions that strengthened impact of WLD. In nutrient‐poor site, tree establishment was seen only in the FD area. In addition to high nutrient level, high wetness accelerated change at the plant community level, where we found three types of responses: accelerating change, decelerating change, and stability. Succession resulted in an overall loss of community heterogeneity. Conclusions Interaction between hydrology, nutrient availability, and biological factors in boreal peatlands is important: the drop in water table required to achieve the shift from open peatland to forested system is inversely proportional to the nutrient level of the system. The results suggest that predictive models of peatland functions under climate change should consider compositional change for fens and their diverse plant communities but are more realistic for bogs. The response of bog vegetation to climate change may, however, be more dependent on changes in rainfall regime and therefore needs to be further addressed. Our paper tracks for the first time the different development pathways of varying peatland vegetation types in response to long‐term water level drawdown. We found that the so‐called tipping point, a drop of water table at which an open peatland undergoes significant vegetation change or transitions to a forest system, is inversely proportional to the nutrient level of the system.