2013 Annual Report
1a.Objectives (from AD-416):
Quantify grassland carbon, energy, water, and GHG fluxes; grassland phenology, and biophysical and biochemical parameters to improve remote sensing monitoring methods and develop understanding of grassland ecosystem dynamics.
1b.Approach (from AD-416):
In Phase 1, we will deploy two CO2 eddy covariance flux towers, one a fixed position for long-term measurements, and one mobile flux tower for experiments (e.g., livestock grazing, fire, land use change). The eddy covariance flux towers are used to measure CO2, water and energy fluxes at 30-minute intervals. Phenology towers will be co-located with the fixed position eddy flux tower, and the mobile eddy flux tower. The phenology towers will use a webcam system to acquire digital photos to track vegetation dynamics at hourly to daily intervals. To measure biophysical and biochemical parameters, we will put deploy two spectral sensor towers, one co-located with the fixed position eddy flux tower, and the other one is co-located with the mobile eddy flux tower. Spectral sensors measure optical properties of vegetation and soils, which helps interpretation of flux data and supports retrieval of grassland biophysical and biochemical parameters from satellite images. In future phases, we will deploy instrumentation to measure soil moisture dynamics, GHG emissions, an optical sensor track system, and airborne observation systems.
One permanent greenhouse gas flux tower has been co-located with the El Reno Mesonet site over tall grass prairie and a second has been installed on improved warm-season pasture. Collection of carbon dioxide, water, and energy fluxes is underway. Calibration of the sensors for methane evaluation will be completed by the end of FY13 so that monitoring of methane emissions will begin in fall of 2013.