Mid‐latitude shrub steppe plant communities: climate change consequences for soil water resources

Abstract

In the coming century, climate change is projected to impact precipitation and temperature regimes worldwide, with especially large effects in drylands. We use big sagebrush ecosystems as a model dryland ecosystem to explore the impacts of altered climate on ecohydrology and the implications of those changes for big sagebrush plant communities using output from 10 Global Circulation Models (GCMs) for two representative concentration pathways (RCPs). We ask: (1) What is the magnitude of variability in future temperature and precipitation regimes among GCMs and RCPs for big sagebrush ecosystems, and (2) How will altered climate and uncertainty in climate forecasts influence key aspects of big sagebrush water balance? We explored these questions across 1980-2010, 2030-2060, and 2070-2100 to determine how changes in water balance might develop through the 21st century. We assessed ecohydrological variables at 898 sagebrush sites across the western US using a process-based soil water model, SOILWAT, to model all components of daily water balance using site-specific vegetation parameters and site-specific soil properties for multiple soil layers. Our modeling approach allowed for changes in vegetation based on climate. Temperature increased across all GCMs and RCPs, whereas changes in precipitation were more variable across GCMs. Winter and spring precipitation was predicted to increase in the future (7% by 2030-2060, 12% by 2070-2100), resulting in slight increases in soil water potential (SWP) in winter. Despite wetter winter soil conditions, SWP decreased in late spring and summer due to increased evapotranspiration (6% by 2030-2060, 10% by 2070-2100) and groundwater recharge (26% and 30% increase by 2030-2060 and 2070-2100). Thus, despite increased precipitation in the cold season, soils may dry out earlier in the year, resulting in potentially longer, drier summer conditions. If winter precipitation cannot offset drier summer conditions in the future, we expect big sagebrush regeneration and survival will be negatively impacted, potentially resulting in shifts in the relative abundance of big sagebrush plant functional groups. Our results also highlight the importance of assessing multiple GCMs to understand the range of climate change outcomes on ecohydrology, which was contingent on the GCM chosen.

Adapting management to a changing world: Warm temperatures, dry soil, and interannual variability limit restoration success of a dominant woody shrub in temperate drylands

“…However, enabling restoration in warmer and increasingly variable climates will require identifying key demographic transitions and environmental conditions driving species, such as sagebrush, so that intervention efforts can be planned to maximize success (Bradford et al., ; Hardegree et al., ). One of the most robust and consistent climate projections in the Great Basin is increasing temperatures which will lead to declines in snowpack, regardless of the effect on total precipitation (Collins et al., ; Palmquist et al., ). Our results suggest that this increased warming and associated declines in snowpack and spring soil moisture are likely to exacerbate ongoing challenges in establishing perennial plants like sagebrush after fire.…”

“…Here, we examine the impact of annual environmental conditions, including temperature, precipitation, snowpack, and soil moisture, on the success of sagebrush restoration after fire in the Great Basin of western North America. Big sagebrush plant communities in the Great Basin are expected to experience increased warming, declines in snowpack, and increased interannual variability in weather, including precipitation amount in the next century (Collins et al., ; Palmquist, Schlaepfer, Bradford, & Lauenroth, , ). Using field data and process‐based soil water modeling at 771 plots across the Great Basin, we examine whether environmental conditions at the time of seeding can help explain the likelihood of sagebrush occurrence at plots that were seeded after fire.…”

Habitat specialists as conservation umbrellas: Do areas managed for greater sage‐grouse also protect pygmy rabbits?

“…Additionally, increased precipitation seasonality coupled with longer dryer summers is predicted by current climate modeling which can negatively impact sagebrush communities (Schlaepfer et al 2012, Palmquist et al 2016). Additionally, increased precipitation seasonality coupled with longer dryer summers is predicted by current climate modeling which can negatively impact sagebrush communities (Schlaepfer et al 2012, Palmquist et al 2016).…”

Influences of potential oil and gas development and future climate on Sage‐grouse declines and redistribution

“…Climate can affect many sagebrush system processes and states (Palmquist et al. ), and could have lagged effects on sage‐grouse demography as a result of changes in temperature and precipitation, interspecific interactions, physiological intolerances, catastrophes, and challenges associated with increasingly severe weather (Foden et al. , Gibson et al.…”