Location: Rangeland Resources Research
Project Number: 3018-11000-005-00
Start Date: May 01, 2010
End Date: Apr 30, 2015
To address our first objective concerning the responses of rangelands to global changes, we will use a well-replicated Free Air CO2 Enrichment (FACE) and warming experiment to determine how global change influences the northern mixed-grass prairie. We will examine responses of plant production and quality, composition of native plant communities, carbon and nitrogen cycling, and plant invasion. To understand the mechanisms underlying these responses, we will make extensive use of gas exchange, stable isotope, soil water and nitrogen monitoring, and computer simulation methods. We will use additional treatments to learn how seasonality of precipitation influences the northern mixed-grass prairie, and how the magnitude of those effects compares to effects of CO2 and warming. To address our second objective concerning greenhouse gas mitigation tools, we will measure soil respiration and fluxes of nitrous oxide (N2O) and methane (CH4) using static chambers, and net ecosystem CO2 exchange (NEE) using dynamic chambers within plots of the FACE, warming and irrigation manipulative experiment. Results from the static and dynamic chambers will allow us to quantify CO2-enrichment and warming effects on soil trace gas fluxes and ecosystem level CO2 fluxes, and how these fluxes are related to soil moisture and other environmental factors. We will also take advantage of three ongoing NP215 long-term grazing studies to assess the effects of grazing management strategies (stocking rate and season of use) on the size and dynamics of soil C and N pools, and the potential of these strategies to mitigate greenhouse gas emissions in NMP and SGS. We will use natural variation in precipitation to determine the relative influence of above- and below-average years of precipitation on C and N pool changes. The insights provided by these experiments will help scientists and land managers adapt management practices to sustain ecosystem services in the face of global change, and provide critical information for policy makers. Utilize collaborative efforts within USDA (ARS, FS, NRCS, RMA, FSA and ERS) as well with other governmental entities (NOAA, USGS, BLM, NWS), land grant university agricultural experiment stations and agricultural extension (in Northern Plains regional states of WY, CO, MT, ND, SD and NE) to synthesize information and data and knowledge to develop technologies (management strategies, management practices) and decision support tools (applications for mobile devices, enhanced models) that can be delivered to land managers via web portals and other technology transfer providers (extension, education, NRCS field offices, eXtension, etc.). An outreach coordinator is needed to manage the 6 state efforts.