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Endemic species of ectomycorrhizal fungi (EMF) are found throughout many biomes, but it is unclear whether their localized distribution is dictated by habitat filtering or geographical barriers to dispersal. We examined community composition (via long-read metabarcoding) and differences in sporocarp nutrition between endemic and cosmopolitan EMF species across perhumid temperate rainforests of British Columbia, characterized by soils with high nitrogen (N) supply alongside low phosphorus (P) and cation availability. Endemic EMF species, representing almost half of the community, had significantly greater sporocarp N (24% higher), potassium (+16%), and magnesium (+17%) concentrations than cosmopolitan species. Sporocarp P concentrations were comparatively low and did not differ by fungal range. However, sporocarp N% and P% were well correlated, supporting evidence for linkages in N and P acquisition. Endemics were more likely to occur on Tsuga heterophylla (a disjunct host genus) than Picea sitchensis (a circumpolar genus). The Inocybaceae and Thelephoraceae families had high proportions of endemic taxa, while species in Cortinariaceae were largely cosmopolitan, indicating some niche conservatism among genera. We conclude that superior adaptive traits in relation to perhumid soils were skewed toward the endemic community, underscoring the potentially important contribution of these localized fungi to rainforest nutrition and productivity., (© 2023 His Majesty the King in Right of Canada and The Authors. New Phytologist © 2023 New Phytologist Foundation. Reproduced with the permission of the Minister of Forests.)

This paper presents a stable isotope and radiocarbon study on a total of 85 samples of wild boar (Sus scrofa), humans (Homo sapiens), dogs (Canis familiaris), red deer (Cervus elaphus) and roe deer (Capreolus capreolus) from four Late Mesolithic sites in Jutland, Denmark. Four of the eight Sus scrofa samples from one site, the shell midden of Fannerup F, show markedly enriched carbon and nitrogen isotope values, indicating a dietary intake of a substantial amount of marine food. In contrast to standard interpretations of Late Mesolithic animal economy, we suggest that the enriched values of Sus scrofa may be an indication of management by Ertebølle groups in the area that facilitated access to substantial amounts of marine foods for these wild boars compared to contemporaneous conspecifics. The 14C dates of the Sus scrofa range from 5290 to 4335 cal BC, suggesting that the management of Sus scrofa developed independently of contact with Neolithic societies. Although the sample size remains small, the interpretation of Late Mesolithic animal management adds to the growing evidence for political and economic complexity in the Ertebølle culture. [ABSTRACT FROM AUTHOR]

Quantifying nutritional dynamics of free-living saprotrophs and symbiotic ectomycorrhizal fungi in the field is challenging, but the stoichiometry of fruiting bodies (sporocarps) may be an effective methodology for this purpose. Carbon (C), nitrogen (N) and phosphorus (P) concentrations of soils, foliage and 146 sporocarp collections were analyzed from 14 Pseudotsuga menziesii var. menziesii stands across a podzolization gradient on Vancouver Island (Canada). N and P concentrations were considerably higher in saprotrophic fungi. Fungal N% increased with soil N content at a greater rate for saprotrophs than ectomycorrhizal fungi, while fungal P% of saprotrophs was more constrained. Fungal N : P was more responsive to soil N : P for ectomycorrhizal fungi (homeostatic regulation coefficient 'H' = 2.9) than saprotrophs (H = 5.9), while N : P of ectomycorrhizal fungi and host tree foliage scaled almost identically. Results underscore the role of ectomycorrhizal fungi as nutrient conduits, supporting host trees, whereas saprotrophs maintain a greater degree of nutritional homeostasis. Site nutrient constraints were shared in equal measure between ectomycorrhizal fungi and host trees, particularly for P, suggesting neither partner benefits from enhanced nutrition at the expense of the other. Sporocarp stoichiometry provides new insights into mycorrhizal relationships and illustrates pervasive P deficiencies across temperate rainforests of the Pacific Northwest., (© 2018 Province of British Columbia New Phytologist © 2018 New Phytologist Trust.)

The Abbotsford-Sumas aquifer (ASA) has a history of nitrate contamination from agricultural land use and manure application to soils, yet little is known about its microbial groundwater quality. The goal of this study was to investigate the spatiotemporal distribution of pathogen indicators (Escherichia coli [E. coli] and total coliform [TC]) and nitrate in groundwater, and their potential relation to hydrologic drivers. Sampling of 46 wells over an 11-month period confirmed elevated nitrate concentrations, with more than 50% of samples exceeding 10 mg-N/L. E. coli detections in groundwater were infrequent (4 of 385 total samples) and attributed mainly to surface water-groundwater connections along Fishtrap Creek, which tested positive for E. coli in every sampling event. TC was detected frequently in groundwater (70% of samples) across the ASA. Generalized additive mixed models (GAMMs) yielded valuable insights into relationships between TC or nitrate and a range of spatial, temporal, and hydrologic explanatory variables. Increased TC values over the wetter fall and winter period were most strongly related to groundwater temperatures and levels, while precipitation and well location were weaker (but still significant) predictors. In contrast, the moderate temporal variability in nitrate concentrations was not significantly related to hydrologic forcings. TC was relatively widespread across the ASA and spatial patterns could not be attributed solely to surface water connectivity. Varying nitrate concentrations across the ASA were significantly related to both well location and depth, likely due to spatially variable nitrogen loading and localized geochemical attenuation (i.e., denitrification). Vulnerability of the ASA to bacteria was clearly linked to hydrologic conditions, and was distinct from nitrate, such that a groundwater management strategy specifically for bacterial contaminants is warranted., (Copyright © 2015 Elsevier B.V. All rights reserved.)

To predict the likely effects of management action on any point source discharge into the coastal ocean, it is essential to understand both the composition of the effluent and the environmental conditions in the receiving waters. We illustrate a broadly-applicable approach to evaluating the comprehensive environmental footprint of a discharge, using regional geochemical budgets and nearfield monitoring. We take as a case study municipal effluent discharged into the Strait of Georgia (west coast of Canada), where there has been public controversy over the discharge of screened or primary-treated effluent directly into the ocean. Wastewater contributes ≤ 1% of the nitrogen, organic carbon and oxygen demand in the Strait and is unlikely to cause eutrophication, harmful algal blooms or hypoxia in this region. Metals (Hg, Pb, Cd) are controlled by natural cycles augmented by past mining and urbanization, with 0.3-5% of the flux contributed by wastewater. Wastewater contributes ~5% of PCBs but ≤ 60% of PBDEs and is likely also important for pharmaceuticals and personal care products. Effects of high organic flux on benthos are measurable in the immediate receiving environment. The availability of particle-active contaminants to enter the food chain depends on how long those contaminants remain in the sediment surface mixed layer before burial. Secondary treatment, slated for completion in Vancouver in 2030, will reduce fluxes of some contaminants, but will have negligible effect on regional budgets for organic carbon, nitrogen, oxygen, metals and PCBs. Removal of PBDEs from wastewater will affect regional budgets, depending on how the sludge is sequestered., (Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.)