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Most terrestrial angiosperms form mutualisms with both mycorrhizal fungi and animal pollinators. Yet, the effects of mycorrhizae on pollinator behavior and plant reproduction are unknown for most species, and whether the source or type of mycorrhizal fungi affects reproductive success has rarely been examined. We examined whether inoculating highbush blueberry ( Vaccinium corymbosum ; Ericaceae) with ericoid mycorrhizal fungi enhanced investment in flowering and attractiveness to pollinators, and thus reduced their levels of pollen limitation over that of non-inoculated plants. We also examined the degree to which pollen limitation was dependent on inoculation source and the surrounding pollinator community context. Three-year-old saplings of Vaccinium corymbosum ‘Bluecrop’ or highbush blueberry (Ericaceae) were inoculated with a) ericoid mycorrhizal fungi within soil of the rhizosphere of plants growing at a local blueberry farm, b) a commercially available ericoid inoculant, c) both the local soils and commercial inoculum, or d) were not inoculated and served as controls. They were grown for one year in pots in a common garden and, in the following year, were moved to six farms in central Vermont that were known from prior studies to differ in pollinator abundance and diversity. We conducted a hand pollination experiment at each farm to examine if inoculation or pollinator abundance (i.e., farm context) affected reproductive success. Plants treated with all types of inoculums were more likely to flower, and produced more inflorescence buds than non-inoculated plants in 2018. However, in 2019, plants in the combination inoculum treatment, alone, produced more inflorescence buds than those in the other treatments. Neither the source of inoculum nor hand pollination affected fruit set (the proportion of flowers setting fruit), or fruit sugar content. Hand pollination, but not inoculation, increased berry mass and the average number of seeds produced/berry. Our results add to the growing body of evidence that mycorrhizal fungi can affect reproductive traits of their hosts but that the effects of mycorrhizal fungi depend on the mycorrhizal symbionts. 

Food system sustainability, and ways of measuring it, are widely explored and discussed in academic literature. Measurement efforts are challenging because food systems are inherently complex and multifaceted, spanning diverse components, indus­tries, sectors, and scales. Several systems of indica­tors and metrics have been proposed to measure sustainability; however, most existing research focuses either on narrow scales (e.g., farm level or within a single supply chain), expansive scales that can gloss over complexity (e.g., national or global assessments), or limited scopes (e.g., only consider­ing environmental factors). A gap in the literature is a holistic local or regional approach to food sys­tem sustainability that integrates components across the system at a regional scale. In this reflec­tive essay, we describe our development of a framework to measure and track sustainability in such systems. We use a tiered framework that includes five sustainability dimensions and a system of indices, indicators, and metrics that allows for the measurement of important food system charac­teristics in a feasible and reproducible way. We employ a collaborative, transdisciplinary, facilitated team science process to first propose, and then refine, a sustainability assessment framework, using the U.S. state of Vermont as a case study. This paper details our process and progress, as well as reflections on challenges and recommendations for other team scientists. We further propose a plan to implement the framework, collect data, and engage with community members. The experiences and findings described here serve as a foundation for our own team’s continued work, as well as a springboard for other similar research efforts. 

Abstract Addressing how ecosystem services (ES) are distributed among groups of people is critical for making conservation and environmental policy-making more equitable. Here, we evaluate the distribution and equity of changes in ES benefits across demographic and socioeconomic groups in the United States (US) between 2020 and 2100. Specifically, we use land cover and population projections to model potential shifts in the supply, demand, and benefits of the following ES: provision of clean air, protection against a vector-borne disease (West Nile virus), and crop pollination. Across the US, changes in ES benefits are unevenly distributed among socioeconomic and demographic groups and among rural and urban communities, but are relatively uniform across geographic regions. In general, non-white, lower-income, and urban populations disproportionately bear the burden of declines in ES benefits. This is largely driven by the conversion of forests and wetlands to cropland and urban land cover in counties where these populations are expected to grow. In these locations, targeted land use policy interventions are required to avoid exacerbating inequalities already present in the US.