Shrub range expansion alters diversity and distribution of soil fungal communities across an alpine elevation gradient

Abstract

Global climate and land use change are altering plant and soil microbial communities worldwide, particularly in arctic and alpine biomes where warming is accelerated. The widespread expansion of woody shrubs into historically herbaceous alpine plant zones is likely to interact with climate to affect soil microbial community structure and function; however, our understanding of alpine soil ecology remains limited. This study aimed to (i) determine whether the diversity and community composition of soil fungi vary across elevation gradients and to (ii) assess the impact of woody shrub expansion on these patterns. In the White Mountains of California, sagebrush (Artemisia rothrockii) shrubs have been expanding upwards into alpine areas since 1960. In this study, we combined observational field data with a manipulative shrub removal experiment along an elevation transect of alpine shrub expansion. We utilized next-generation sequencing of the ITS1 region for fungi and joint distribution modelling to tease apart effects of the environment and intracommunity interactions on soil fungi. We found that soil fungal diversity declines and community composition changes with increasing elevation. Both abiotic factors (primarily soil moisture and soil organic C) and woody sagebrush range expansion had significant effects on these patterns. However, fungal diversity and relative abundance had high spatial variation, overwhelming the predictive power of vegetation type, elevation and abiotic soil conditions at the landscape scale. Finally, we observed positive and negative associations among fungal taxa which may be important in structuring community responses to global change.

Habitat specialisation controls ectomycorrhizal fungi above the treeline in the European Alps

“…Similarly, Collins et al . (2018) found that overall soil fungal richness and diversity declined with elevation, but differences were more pronounced between subalpine and alpine sites and were not significant within alpine sites. Adamczyk et al .…”

“…(2012) found that EM fungal richness declined monotonically with increasing elevation. This declining trend with increasing elevation has been reported from mountains around the globe, from Mount Fuji (Miyamoto et al ., 2014) to the Andes (Nottingham et al ., 2018) and White Mountains (Collins et al ., 2018). These studies were carried out across multiple habitats and included different plant hosts that covaried with elevation resulting in confounding effects.…”

Temporal and spatial succession and dynamics of soil fungal communities in restored grassland on the Loess Plateau in China

“…For example, at the local scale (within 28 km distance), soil fungal communities were found distributed along an age gradient of managed Pinus sylvestris stands (Kyaschenko, Clemmensen, Hagenbo, Karltun, & Lindahl, ) and to reciprocally interact with plant factors and soil properties (Bender et al, ; Heijden, Bruin, Luckerhoff, Logtestijn, & Schlaeppi, ). Along with elevation gradient, soil fungal communities show lineage‐specific biogeographic patterns in grassland system (Pellissier et al, ); similarly, abiotic factors and woody sagebrush range expansion have significant effects on the patterns that soil fungal diversity declines and community composition changes with increasing elevation in shrubland system (Collins, Stajich, Weber, Pombubpa, & Diez, ). In addition, soil fungal species composition differs between forests, depending on the dominant tree species (Yamashita & Hijii, ) and forest management practices (Kranabetter, Friesen, Gamiet, & Kroeger, ).…”

Soil Microbial Networks Shift Across a High-Elevation Successional Gradient

“…Previous studies have used microbial co-occurrence patterns to construct networks and make inferences about microbial interactions (Barberán et al, 2012;Widder et al, 2014;Williams et al, 2014;Morriën et al, 2017;de Vries et al, 2018); however, these methods are limited because microbial co-occurrence can reflect both species interactions (e.g., predation, facilitation, decomposition) and shared environmental niches (co-occurrence due to shared preference for abiotic conditions). Recent advances in hierarchical joint species distribution modeling allow us to parse out the effect of environmental variables to better capture interactions per se (Hui and Poisot, 2016;Ovaskainen et al, 2017); yet they have rarely been applied to microbial datasets (Collins et al, 2018). Here we used this technique to test whether patterns in the complexity of bacterial and eukaryotic networks follow patterns in diversity and compositional change across a fundamental gradient, ecological succession.…”