Phosphorus levels, phenology of roots and shoots, and development of vesicular arbuscular mycorrhizal (VAM) fungi were monitored for two years in natural populations of the perennial alpine herb, Ranunculus adoneus. The purpose of this study was to understand how phosphorus uptake relates to the phenology of R. adoneus and to ascertain whether arbusculus, fungal structures used for nutrient transfer, were present when maximum phosphorus accumulation was occurring. Arbuscules were only present for a few weeks during the growing season of R. adoneus and their presence corresponded with increased phosphorus accumulation in both the roots and shoots of R. adoneus. In addition, phosphorus accumulation and peaks in mycorrhizal development occurred well after plant reproduction and most plant growth had occurred. The late season accumulation of phosphorus by mycorrhizal roots of R. adoneus is stored for use during early season growth and flowering the following spring. In this way R. adoneus can flower before soils thaw and root or mycorrhizal nutrient uptake can occur.

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Alpine areas in northwestern Yunnan, China possess globally significant levels of biodiversity and are important locally for livelihood activities such as livestock grazing and medicinal plant collection. Because local land use has important impacts on alpine conditions and communities have significant capacity to manage alpine resources, we emphasized local collaboration during the initial stages of conservation planning. Our collaboration with local communities investigated how livelihood strategies affect the condition of alpine resources in northwestern Yunnan and how future conservation efforts can be compatible with local livelihoods. We sampled three livestock herding sites, each within a different alpine sub-region, using open-ended interviews and maximum variation sampling. According to interviewees, livestock grazing within the alpine zone currently does not appear to be negatively impacting the availability of forage. Medicinal plant collection, however, is showing unsustainable trends. Tourism is as yet a nascent industry, but is seen as having great potential by those interviewed. It is clear that with increases in population, access to regional markets, and tourism, northwestern Yunnan's rich alpine resources will require careful management. In addition to the data collected, we found that the methodology used may be widely applicable to organizations with limited resources that wish to engage local communities during the formative stages of regional-level conservation planning.

Summary• Dark-septate endophytic (DSE) fungi are ubiquitous in the roots of Arctic and alpine plants, yet very little is known about their phylogenetic identities or effects on their host plants.• Several such fungi were isolated from the alpine snowbed plant Ranunculus adoneus in the Front Range of Colorado, USA; one isolate was chosen for detailed study. The ability of this isolate to re-colonize plant roots in pot cultures was assessed, and phylogenetic analyses were performed using small-subunit (SSU), 5.8S and internal transcribed spacer (ITS) 2 ribosomal DNA sequences.• This isolate had the ability to produce root endophytic structures in pot cultures similar to those reported from other sources and observed in R. adoneus roots. SSU phylogenetic analyses showed this isolate to be related to a clade within the Euascomycetes containing the Leotiales and Erysiphales. In addition, SSU and 5.8S -ITS2 sequences showed high phylogenetic similarity to a variety of isolates reported from other plants of diverse geographical origins. Although most of these isolates remain unidentified, one closely related isolate was the anamorphic taxon Phialophora gregata .• The results suggest that this DSE isolate might belong to the fairly closely related group of plant endophytes that have varied effects on the plants that they inhabit.