Warming-El Nino-Nitrogen Deposition Experiment (WENNDEx): Soil Temperature, Moisture, and Carbon Dioxide Data from the Sevilleta National Wildlife Refuge, New Mexico

Humans are creating significant global environmental change,
including shifts in climate, increased nitrogen (N) deposition, and
the facilitation of species invasions. A multi-factorial field
experiment is being performed in an arid grassland within the
Sevilleta National Wildlife Refuge (NWR) to simulate increased
nighttime temperature, higher N deposition, and heightened El Nino
frequency (which increases winter precipitation by an average of
50%). The purpose of the experiment is to better understand the
potential effects of environmental drivers on grassland community
composition, aboveground net primary production and soil
respiration. The focus is on the response of two dominant grasses
(Bouteloua gracilis and B eriopoda), in an ecotone near their range
margins and thus these species may be particularly susceptible to
global environmental change. It is hypothesized that warmer summer
temperatures and increased evaporation will favor growth of black
grama (Bouteloua eriopoda), a desert grass, but that increased
winter precipitation and/or available nitrogen will favor the growth
of blue grama (Bouteloua gracilis), a shortgrass prairie species.
Treatment effects on limiting resources (soil moisture, nitrogen
availability, species abundance, and net primary production (NPP)
are all being measured to determine the interactive effects of key
global change drivers on arid grassland plant community dynamics and
ecosystem processes. This dataset shows values of soil moisture,
soil temperature, and the CO2 flux of the amount of CO2 that has
moved from soil to air. On 4 August 2009 lightning ignited a ~3300
ha wildfire that burned through the experiment and its surroundings.
Because desert grassland fires are patchy, not all of the replicate
plots burned in the wildfire. Therefore, seven days after the
wildfire was extinguished, the Sevilleta NWR Fire Crew thoroughly
burned the remaining plots allowing us to assess experimentally the
effects of interactions among multiple global change presses and a
pulse disturbance on post-fire grassland dynamics.