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Climate change negatively impacts reindeer grazing in Fennoscandia, with the encroachment of Empetrum nigrum (crowberry) being a significant, yet largely unrecognized problem. Crowberry encroachment affects the neighboring palatable vegetation negatively, homogenizing the pasture and decreasing ecosystem biodiversity. Current husbandry management aims are based on sustainable use of the pasture land, yet pasture quality is not considered a central indicator. To prevent overgrazing, reindeer numbers are limited, but as the animals avoid crowberry, this invasive species exacerbates the Norwegian reindeer husbandry's pasture crisis. Herders therefore intervene with two adaptive strategies, supplementary feeding and/or crowberry control. We develop a general three-species bioeconomic model with five variants to understand the economic impact of an invasive species on herbivore husbandry, and the net benefits of the two adaptive measures at the steady state. Our analytical results show that the native invasive encroachment causes a decrease in not only the nutrient-high grazing land but also the optimal herbivore herd and slaughter volume. Supplementary feeding is implemented to increase the herd size, yet the measure further depletes the grazing pasture, making this practice unsustainable. Instead, controlling crowberry protects both the grazing pasture and reindeer herd size. Applying this to the Norwegian reindeer husbandry case, we find crowberry control more cost-effective and less stressful for the pasture land than supplementary feeding. Government subsidies are shown to be essential for restoring herd sizes to the status quo., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Pham Minh Nhat reports financial support was provided by Norges Forskiningsrad. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

How the multiple facets of soil fungal diversity vary worldwide remains virtually unknown, hindering the management of this essential species-rich group. By sequencing high-resolution DNA markers in over 4000 topsoil samples from natural and human-altered ecosystems across all continents, we illustrate the distributions and drivers of different levels of taxonomic and phylogenetic diversity of fungi and their ecological groups. We show the impact of precipitation and temperature interactions on local fungal species richness (alpha diversity) across different climates. Our findings reveal how temperature drives fungal compositional turnover (beta diversity) and phylogenetic diversity, linking them with regional species richness (gamma diversity). We integrate fungi into the principles of global biodiversity distribution and present detailed maps for biodiversity conservation and modeling of global ecological processes.

Small rodents are prevalent and functionally important across the world's biomes, making their monitoring salient for ecosystem management, conservation, forestry, and agriculture. There is a growing need for cost-effective and noninvasive methods for large-scale, intensive sampling. Fecal pellet counts readily provide relative abundance indices, and given suitable analytical methods, feces could also allow for the determination of multiple ecological and physiological variables, including community composition. In this context, we developed calibration models for rodent taxonomic determination using fecal near-infrared reflectance spectroscopy (fNIRS). Our results demonstrate fNIRS as an accurate and robust method for predicting genus and species identity of five coexisting subarctic microtine rodent species. We show that sample exposure to weathering increases the method's accuracy, indicating its suitability for samples collected from the field. Diet was not a major determinant of species prediction accuracy in our samples, as diet exhibited large variation and overlap between species. fNIRS could also be applied across regions, as calibration models including samples from two regions provided a good prediction accuracy for both regions. We show fNIRS as a fast and cost-efficient high-throughput method for rodent taxonomic determination, with the potential for cross-regional calibrations and the use on field-collected samples. Importantly, appeal lies in the versatility of fNIRS. In addition to rodent population censuses, fNIRS can provide information on demography, fecal nutrients, stress hormones, and even disease. Given the development of such calibration models, fNIRS analytics could complement novel genetic methods and greatly support ecosystem- and interaction-based approaches to monitoring., Competing Interests: The authors declare no competing interests., (© 2023 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)

Fungi are highly diverse organisms, which provide multiple ecosystem services. However, compared with charismatic animals and plants, the distribution patterns and conservation needs of fungi have been little explored. Here, we examined endemicity patterns, global change vulnerability and conservation priority areas for functional groups of soil fungi based on six global surveys using a high-resolution, long-read metabarcoding approach. We found that the endemicity of all fungi and most functional groups peaks in tropical habitats, including Amazonia, Yucatan, West-Central Africa, Sri Lanka, and New Caledonia, with a negligible island effect compared with plants and animals. We also found that fungi are predominantly vulnerable to drought, heat and land-cover change, particularly in dry tropical regions with high human population density. Fungal conservation areas of highest priority include herbaceous wetlands, tropical forests, and woodlands. We stress that more attention should be focused on the conservation of fungi, especially root symbiotic arbuscular mycorrhizal and ectomycorrhizal fungi in tropical regions as well as unicellular early-diverging groups and macrofungi in general. Given the low overlap between the endemicity of fungi and macroorganisms, but high conservation needs in both groups, detailed analyses on distribution and conservation requirements are warranted for other microorganisms and soil organisms., (© 2022 The Authors. Global Change Biology published by John Wiley & Sons Ltd.)

Plant communities worldwide show varied responses to nutrient enrichment-including shifts in species identity, decreased diversity, and changes in functional trait composition-but the factors determining community recovery after the cessation of nutrient addition remain uncertain. We manipulated nutrient levels in a tundra community for 6 years of nutrient addition followed by 8 years of recovery. We examined how community recovery was mediated by traits related to plant resource-use strategy and plant ability to modify their environment. Overall, we observed persistent effects of fertilization on plant communities. We found that plants with fast-growing traits, including higher specific leaf area, taller stature and lower foliar C:N, were more likely to show a persistent increase in fertilized plots than control plots, maintaining significantly higher cover in fertilized plots 8 years after cessation of fertilization. Additionally, although graminoids responded most strongly to the initial fertilization treatment, forb species were more vulnerable to fertilization effects in the long-term, showing persistent decline and no recovery in 8 years. Finally, these persistent fertilization effects were accompanied by modified environmental conditions, including persistent increases in litter depth and soil phosphorous and lower soil C:N. Our results demonstrate the potential for lasting effects of nutrient enrichment in nutrient-limited systems and identify species traits related to rapid growth and nutrient-use efficiency as the main predictors of the persistence of nutrient enrichment effects. These findings highlight the usefulness of trait-based approach for understanding the persistent feedbacks of nutrient enrichment, plant dynamics, and niche construction via litter and nutrient build-up., (© 2021. The Author(s).)

The boreal forest consists of drier sunlit and moister-shaded habitats with varying moss abundance. Mosses control vascular plant-soil interactions, yet they all can also be altered by grazers. We determined how 2 decades of reindeer (Rangifer tarandus) exclusion affect feather moss (Pleurozium schreberi) depth, and the accompanying soil N dynamics (total and dissolvable inorganic N, δ 15 N), plant foliar N, and stable isotopes (δ 15 N, δ 13 C) in two contrasting habitats of an oligotrophic Scots pine forest. The study species were pine seedling (Pinus sylvestris L.), bilberry (Vaccinium myrtillus L.), lingonberry (V. vitis-idaea L.), and feather moss. Moss carpet was deeper in shaded than sunlit habitats and increased with grazer exclusion. Humus N content increased in the shade as did humus δ 15 N, which also increased due to exclusion in the sunlit habitats. Exclusion increased inorganic N concentration in the mineral soil. These soil responses were correlated with moss depth. Foliar chemistry varied due to habitat depending on species identity. Pine seedlings showed higher foliar N content and lower foliar δ 15 N in the shaded than in the sunlit habitats, while bilberry had both higher foliar N and δ 15 N in the shade. Thus, foliar δ 15 N values of co-existing species diverged in the shade indicating enhanced N partitioning. We conclude that despite strong grazing-induced shifts in mosses and subtler shifts in soil N, the N dynamics of vascular vegetation remain unchanged. These indicate that plant-soil interactions are resistant to shifts in grazing intensity, a pattern that appears to be common across boreal oligotrophic forests., (© 2021. The Author(s).)

The interactive effects of consumers and nutrients on terrestrial plant communities, and the role of plant functional traits in mediating these responses, are poorly known. We carried out a six-year full-factorial field experiment using mammalian herbivore exclusion and fertilization in two habitat types (fertile and infertile alpine tundra heaths) that differed in plant functional traits related to resource acquisition and palatability. Infertile habitats were dominated by species with traits indicative of a slow-growing strategy: high C:N ratio, low specific leaf area, and high condensed tannins. We found that herbivory counteracted the effect of fertilization on biomass, and that this response differed between the two habitats and was correlated with plant functional traits. Live biomass dominated the treatment responses in infertile habitats, whereas litter accumulation dominated the treatment responses in fertile habitats and was strongly negatively associated with resident community tannin concentration. Species richness declined under herbivore exclusion and fertilization in fertile habitats, where litter accumulation was greatest. Community means of plant C:N ratio predicted treatment effects on diversity: fertilization decreased and herbivory increased dominance in communities originally dominated by plants with high C:N, while fertilization increased and herbivory diminished dominance in communities where low C:N species were abundant. Our results highlight the close interdependence between consumer effects, soil nutrients, and plant functional traits and suggest that plant traits may provide an improved understanding of how consumers and nutrients influence plant community productivity and diversity.