Location: Southwest Watershed Research2013 Annual Report
1a. Objectives (from AD-416):
Science direction for SMAP mission. Specifically the investigation of applicability of the SMAP mission to watershed and ecosysytem management decisions in the southwest.
1b. Approach (from AD-416):
Using existing and developing data assimilation and data fusion techniques to combine SMAP provided data and products with existing knowledge of the watershed environment in a modeling framework to produce information and tools which will be of value to researchers and policymakers.
3. Progress Report:
New satellite sensors are planned to measure plant fluorescence (F) to monitor plant health on a regular basis over large agricultural regions. We conducted a study to determine the relationship between photosynthesis (P) and F with changes in light intensity, and to define the optimum photosynthetic active radiation (PAR) range for assessing physiological plant status with F. This project contributes to objective 1 of the in-house parent project, "Improve watershed management by developing the capacity to more accurately predict soil and plant water dynamics utilizing a combination of remote sensing, modeling and in-situ measurements". A new analytical model was derived to explain the change in F due to varying light intensity. It was demonstrated that for PAR levels close to those used for plant growth, F was directly correlated with P, and differed significantly between the well-watered and water-deficit treatments. This new information provides a promising starting point for interpretation of seasonal changes in F using satellite-based sensors.