Examines how climate change reshapes plant functional traits, soil respiration, and nutrient cycling across elevation gradients in subalpine meadows near Gothic, Colorado.
Mountain ecosystems like those surrounding the Rocky Mountain Biological Laboratory (RMBL) in Gothic, Colorado, are shaped by steep environmental gradients packed into short distances. As one climbs from the valley floors of the Gunnison Basin into the alpine, temperature drops, growing seasons shorten, snow lingers longer, and soils change in age, chemistry, and microbial composition. These elevational gradients act as natural laboratories: by comparing communities at different elevations, researchers can ask how plants and soils may respond to a warming climate without waiting decades for change to unfold (Sundqvist et al., 2013).
A central tool in this research is the functional trait approach. Rather than tracking species one by one, scientists measure characteristics like specific leaf area (SLA, the ratio of leaf area to dry mass), leaf dry matter content, and root mass distribution. These traits reflect plant strategies: thin, large leaves with high SLA tend to grow fast and capture resources quickly, while tough, dense leaves favor conservation and survival in harsh conditions. Traits can be summarized at the community level using community-weighted means, which weight each species' trait values by its abundance. Global databases like TRY have made this approach possible at unprecedented scales (Kattge et al., 2020), and trait responses to temperature and precipitation are now well-documented worldwide (Moles et al., 2014).
Aboveground plant communities are tightly linked to belowground systems, including soil microbes, mycorrhizal fungi, and the processes they drive: soil respiration (the release of CO2 from soils), nitrogen mineralization (conversion of organic nitrogen into plant-available forms), and extracellular enzyme activity (microbial enzymes that break down organic matter). Together these belowground processes regulate carbon and nutrient cycling, controlling whether a meadow is a net source or sink of carbon. A recurring theme in RMBL-area research is dominant species removal: experimentally pulling out the most abundant plant (such as the bunchgrass Festuca thurberi) to test whether ecosystem function hinges on a few key species or is buffered by the wider community. Researchers increasingly combine these removals with experimental warming, often using open-top chambers, to disentangle the direct effects of climate from indirect effects mediated by changes in plant composition.
The functioning of ecosystems including processes such as carbon and nutrient cycling and storage, community- and ecosystem-level responses, and overa...
Global temperature increase and associated changes in precipitation patterns and extreme weather affecting ecosystems worldwide
Spatial gradients in elevation that capture variation in temperature, soil age and type, disturbance regimes, and land-use histories providing importa...
The microbiome's ability to extract energy from dietary sources
A measure of community diversity that accounts for both species richness and relative abundance, calculated using the Shannon-Weiner index
Measurement of plant species-specific cover, identification of focal species, and collection of plant biomass and functional traits including specific...
Continuous measurement of soil CO2 concentrations at multiple depths using automated sensors to calculate soil CO2 fluxes via gradient approach. Inclu...
Comprehensive measurement of vegetative traits including specific leaf area, trichome density, water use efficiency, and percent water content from fi...
A 2×2 factorial experiment combining passive warming using open-top chambers with dominant plant species removal across elevational gradients at multi...
Factorial experiment crossing nitrogen addition treatments with dominant species removal treatments in replicated plots to test community responses to...
Multivariate analysis technique to quantify community responses over time. Treatment weights indicate response magnitude and species weights show indi...
1. Plant functional traits, in particular specific leaf area (SLA), wood density and seed mass, are often good predictors of individual tree growth ra...
Climatic warming affects ecosystem-scale carbon fluxes directly through its impact on photosynthesis and respiration, and indirectly by altering the p...
These data were collected from 2013 to 2022 near the Rocky Mountain Biological Laboratory in Colorado. They are from a climate change experiment that ...
These data are from a 2023 snowmelt manipulation experiment in Vera Meadow at the Rocky Mountain Biological Laboratory. We experimentally advanced the...
Locations and descriptions of the sites where field sampling was conducted during the 2018 National Ecological Observatory Network (NEON) Airborne Obs...
This is data collected to explore the impacts of warming and dominant species removal on the quantity and quality of plants for cattle foraging. The d...
Early synthesis papers established the conceptual scaffolding for this neighborhood. Sundqvist and colleagues showed that elevational gradients are powerful but complicated tools for understanding global change, because temperature, precipitation, and soil properties all shift together (Sundqvist et al., 2013). Global syntheses then quantified how plant traits track climate, finding that mean annual temperature explains more variation in plant traits than precipitation does (Moles et al., 2014), and that warming can drive substantial losses of soil carbon, especially where soil carbon stocks are large (Crowther et al., 2016).
At RMBL specifically, foundational measurements documented that leaf mass per area and root mass per length both decrease with elevation across many species, suggesting consistent trait shifts with the cold, short seasons of higher meadows. Early water-addition experiments revealed that belowground processes respond to changes in moisture on shorter timescales than aboveground plant growth does, foreshadowing the importance of separating short-term microbial responses from longer-term plant community change. Globally, Mayor and colleagues showed that elevation drives convergent shifts in nutrient stoichiometry across treeline ecosystems, linking plant nutrient content to changes in soil organic matter and microbial properties (Mayor et al., 2017).
A central insight from RMBL is that intraspecific variation, differences in traits within a single species, can be as important as differences between species. Read and colleagues showed that within-species trait variation along the West Elk Mountains gradient was higher than global averages and actually swamped interspecific variation, making trait-based models of community composition perform worse than a simple null model (Read et al., 2017). For root traits, almost all variation occurred within rather than between species. This means that a single species growing at different elevations can effectively become a different functional entity.
Dominant species removal and nitrogen addition experiments have repeatedly shown that montane communities are surprisingly resilient. Four years after removing the dominant Festuca thurberi, communities converged back toward the original dominant's traits, while inorganic nitrogen addition boosted aboveground biomass by about 60% without changing species diversity (Read et al., 2017). Fungal partnerships also proved robust: arbuscular mycorrhizal and dark septate endophyte colonization of co-dominant Helianthella quinquenervis did not change after years of nitrogen addition or dominant removal, although proximity to neighboring plants strongly shaped colonization patterns (Henning et al., 2019). Plant removals also had only marginal effects on nitrogen mineralization rates, though they significantly reduced the variability of those rates across the elevation gradient (Rewcastle et al., 2022).
Integrating biodiversity with ecosystem function, Prager and colleagues found that taxonomic, functional, and phylogenetic diversity were each positively linked to peak growing season carbon uptake, but in a combined model only phylogenetic diversity remained a direct driver, with climate acting indirectly through biodiversity (Prager et al., 2021). Belowground patterns, meanwhile, defy simple rules: a global meta-analysis found no consistent relationship between soil microbial diversity and either temperature or soil pH, with linear, humped, trough-shaped, and flat patterns all equally likely across studies (Hendershot et al., 2017).
Research since 2020 has shifted from documenting patterns to explicitly testing how warming and species loss interact, and how those interactions vary across elevations. The Warming and Removal in Mountains (WaRM) network, anchored at RMBL, combines passive warming with dominant species removal at high- and low-elevation sites and uses distributed experiments to overcome the limitations of single-site studies (Prager et al., 2022). Results from this framework show that effects are highly context dependent: warming roughly doubled soil respiration at low elevation but had no detectable effect at high elevation (Sharon, 2020), and warming combined with dominant removal produced interactive effects on microbial biomass and enzyme activity that neither treatment produced alone (Spinella et al., 2024). Plant community responses were similarly site-specific, with warming reducing biomass at low elevation but only removal affecting biomass at high elevation (Calhoun, 2020).
The newest frontier uses whole-community transplants to simulate climate change directly. Moving intact turfs of plants and soil across a 400-meter elevation gradient, Seltzer (Seltzer, 2025) found that soil bacteria and archaea responded fastest to warming, followed by fungi and then plants, with communities shifting within one to two growing seasons to resemble those at the destination elevation. Trait composition shifted from fast-growth strategies toward conservation and survival strategies under warming. Cooling responses were weaker and slower, hinting at asymmetry in how mountain ecosystems will track climate change.
Key uncertainties remain about how aboveground and belowground communities will stay coupled as they respond at different speeds, whether the resilience observed over four to six years of manipulation will hold over decades, and how interactions between warming, drought, nitrogen deposition, and species loss will play out as multiple stressors accumulate. The role of intraspecific trait variation in buffering or amplifying community responses to warming is poorly understood, as is the question of whether dominant species at high elevations will continue to anchor ecosystem function or be replaced by upslope migrants. Better integration of distributed experiments, long-term natural gradients, and emerging tools like hyperspectral imaging will be essential for predicting how the meadows of the Gunnison Basin will look, function, and cycle carbon by mid-century.
Calhoun, M. (2020). Investigating alpine plant community responses to simulated warming and dominant species removal at a low and high elevation in the Colorado Rocky Mountains. →
Crowther, T.W., Todd-Brown, K.E.O., Rowe, C.W., Wieder, W.R., Carey, J.C. (2016). Quantifying global soil carbon losses in response to warming. Nature. →
Hendershot, J.N., Read, Q.D., Henning, J.A., Sanders, N.J., Classen, A.T. (2017). Consistently inconsistent drivers of patterns of microbial diversity and abundance at macroecological scales. Ecology. →
Henning, J.A., Read, Q.D., Sanders, N.J., Classen, A.T. (2019). Fungal colonization of plant roots is resistant to nitrogen addition and resilient to dominant species losses. Ecosphere. →
Kattge, J., Bönisch, G., Díaz, S., Lavorel, S., Prentice, I.C., Leadley, P., Wirth, C. (2020). TRY plant trait database - enhanced coverage and open access. Global Change Biology. →
Mayor, J.R., Sanders, N.J., Classen, A.T., Bardgett, R.D., et al. (2017). Elevation alters ecosystem properties across temperate treelines globally. Nature. →
Moles, A.T., Perkins, S.E., Laffan, S.W. (2014). Which is a better predictor of plant traits: temperature or precipitation? Journal of Vegetation Science. →
Prager, C.M., Boelman, N.T., Eitel, J.U.H., Gough, L., Greaves, H.E., et al. (2021). Climate and multiple dimensions of plant diversity regulate ecosystem carbon exchange along an elevational gradient. Ecosphere. →
Prager, C.M., Classen, A.T., Sundqvist, M.K., Barrios-Garcia, M.N., et al. (2022). Integrating natural gradients, experiments, and statistical modeling in a distributed network experiment: An example from the WaRM Network. Ecology and Evolution. →
Read, Q.D., Henning, J.A., Classen, A.T., Sanders, N.J. (2017). Aboveground resilience to species loss but belowground resistance to nitrogen addition in a montane plant community. Journal of Plant Ecology. →
Read, Q.D., Henning, J.A., Sanders, N.J. (2017). Intraspecific variation in traits reduces ability of trait-based models to predict community structure. Journal of Vegetation Science. →
Rewcastle, K.E., Henning, J.A., Read, Q.D., Sanders, N.J., Classen, A.T. (2022). Plant removal across an elevational gradient marginally reduces rates, substantially reduces variation in mineralization. Ecology. →
Seltzer, L. (2025). The impacts of environmental change on plant and microbial communities: A turf transplant experiment in the Colorado Rocky Mountains. →
Sharon, A. (2020). The Impact of Warming and Species Removal on Soil Respiration at Low and High Elevations. →
Spinella, J., Rewcastle, K.E., Henning, J.A., Classen, A.T. (2024). Context dependence of warming induced shifts in montane soil microbial functions. Functional Ecology. →
Sundqvist, M.K., Sanders, N.J., Wardle, D.A. (2013). Community and Ecosystem Responses to Elevational Gradients: Processes, Mechanisms, and Insights for Global Change. Annual Review of Ecology, Evolution, and Systematics. →
CO2 efflux from soils to atmosphere representing combination of autotrophic respiration (root respiration) and heterotrophic respiration (microbial de...
Population size or density of individual species within a habitat
Net production of plant biomass above ground surface measured as standing crop minus losses to herbivores
Raw material on which ecological and evolutionary processes act - variation of traits within species that can mediate responses to biotic and abiotic ...
Measure of soil acidity/alkalinity that may influence plant phenotype expression
Plant characteristics that reflect ecological strategies, including specific leaf area and leaf dry matter content
Statistical method for recognizing evolutionarily independent lineages based on genealogical patterns in molecular data
Geographic classification system used to reduce complexity and simplify presentation of continental-scale results
Movement of seeds away from parent plants through various mechanisms including wind, animals, and gravity
Variation in organismal body size both within and between species, influenced by environmental and genetic factors
Accounting framework that tracks carbon inputs, transformations, and outputs in environmental systems to quantify net carbon fluxes
The degree to which values at nearby locations are correlated, used to assess spatial clustering in disease patterns
The reciprocal evolutionary change in interacting species driven by natural selection, where adaptations of one species create selective pressures on ...
Describes consistent and strong correlations among plant functional traits reflecting the ecological tradeoffs and constraints of plants around resour...
The percentage of ground area covered by a particular plant species when viewed from above
The ratio of dry root weight to total dry plant weight, used as an indicator of soil nutrient availability with higher values indicating nutrient-poor...
Experimental removal of the most abundant plant species to test effects of species loss on community structure and function
Maximum temperature of warmest month, capturing seasonality in contrast to average annual temperatures
The ability of a system to change but maintain its basic attributes; a resilient forest stand subjected to disturbance will return to conditions simil...
Parasitic plants that retain absorptive roots and are capable of carbon fixation through photosynthesis but still need to draw some of their resources...
Higher temperatures shorten larval developmental period leading to smaller adults, where body size exhibits temperature-mediated variation
Geographic patterns in biodiversity and chemical diversity across latitudinal and environmental gradients
Total amount of living microbial tissue in soil measured as carbon and nitrogen content
Species with greater primary production exert the main controls for the functioning of ecosystems due to greater aboveground abundance of biomass or l...
Plot showing cumulative number of species discovered as a function of sampling effort, used to assess sampling completeness
Activity of enzymes secreted by soil microorganisms that catalyze decomposition of organic matter and provide assimilable carbon and nitrogen compound...
Underground ecosystem components crucial for sustaining ecosystem function but often remain unseen
Rate of nonsynonymous substitutions per nonsynonymous site normalized by synonymous substitutions per synonymous site (dN/dS)
Biogeochemical model that accounts for moisture-dependent activation and dormancy of distinct microbial communities at different effective saturations
A relationship between plumage coloration and climate variation, predicting that darker coloration due to pigmentation occurred in warmer, more humid ...
Remote sensing technique using wavelengths from 400-1000 nanometers to capture spectral signatures
Predicts that dominant species may be more specialized on particular resources than subordinates, allowing subordinate species to coexist by better ca...
Data from: Aboveground resilience to species loss but belowground resistance to nitrogen addition in a montane plant community, Read, Quentin D., Henn...
The leaf economics spectrum (LES) describes a major axis of plant functional trait variation worldwide, defining suites of leaf traits aligned with re...
Seed size and toughness affect seed predators, and size-dependent investment in mechanical defence could affect relationships between seed size and pr...
In 1993, we installed 40 circular, 10 m radius biometric plots in the footprint of the EMS tower on Prospect Hill. We randomly placed the plots within...
While community-weighted means of plant traits have been linked to mean environmental conditions at large scales, the drivers of trait variation withi...
We examined how abiotic (warming), and biotic (presence of dominant plant species) factors interact to affect soil microbial processes in montane mead...
The manual_soil_measurements_2022_2023.csv data set contains all of the manually measured soil CO 2 efflux, volumetric water content and soil temperat...
The Gunnison Climate Working Group is piloting a on-the-ground climate adaptation project to buildresilience of riparian areas/wet meadows – priority ...
Season length and its associated variables can influence the expression of social behaviors, including the occurrence of eusociality in insects. Among...
These are the data with the accompanying R code used in the article Long-term changes in flowering synchrony reflect climatic changes across an elevat...
Our actions today to build ecosystem resilience to climate change will help us protect the Gunnison Basin’s natural resources—clean air and wildlife h...
File: Peng_et_al._20206.zip Description: There are three folders here. The Data folder contains the raw specimen phenology data and the RMBL phenology...
This is the AmeriFlux version of the carbon flux data for the site US-UR4 Gunnison - UCRB. Site Description - This site is located in Gunnison, Colora...
Webinar on Building Resilience to Climate Change in the Gunnison Basin
IPBES is an independent intergovernmental body comprising over 130 member Governments. Established by Governments in 2012, IPBES provides policymakers...