Water Resources Research Act Program

Details for Project ID 2015PR169B

Mapping Field-Scale Soil Moisture Using Ground-Based L-Band Passive Microwave Observations in Western Puerto Rico

Institute: Puerto Rico
Year Established: 2015 Start Date: 2015-03-03 End Date: 2016-02-28
Total Federal Funds: $20,000 Total Non-Federal Funds: $43,469

Principal Investigators: Jonathan MunozBarreto, Tarendra Lakhankar, Xiwu Zhan

Project Summary: Soil moisture content plays an important role in the exchange of energy and water within the soil-vegetation-atmosphere domain. Successful characterization and modeling of spatial characteristics of soil moisture dynamics is crucial for the prediction of hydrological and meteorological processes. Moreover, spatial and temporal soil moisture information is needed for sustainable agricultural water management, in which large quantities of water are used. Currently, soil moisture content information is generally characterized by intrusive methods, which are limited to point and field scale measurements. In general, these techniques are restricted to small observation areas and are tedious and time consuming. In addition, interpolation of the point-measured soil moisture data can lead to errors from interpolation within the nonlinear soil moisture regime. In the other hand, microwave remote sensing offers great potential for accurate soil moisture estimation from field scale to global scale. Ground-based systems are also of particular interest to improve and validate soil moisture products obtained from satellite remote sensing. The long term goal of this research is to improve forward and inverse modeling approaches for soil moisture retrieval using a ground-based L-band radiometers, specifically over Puerto Rico soils that are representative of soils in the tropics. Therefore, this work may provide information generally applicable to the highly weathered clayey soils common among tropical islands. The proposed project length is three years, corresponding to three phases. In the first phase, the CREST L-band microwave observation unit will be used to establish 3 temporal soil moisture observational sites in Western Puerto Rico. The selected sites (Mayagajas, and Isabela) are part of the Agricultural Experiment Station program and are under the footprint of the Puerto Rico Weather Radar Network . The radar network will provide the sites with a cohesive weather/climatological data sets. The main objective of this proposal in the first phase is to generate a data sets for calibration and validation activities of the upcoming NASA Soil Moisture Active Passive (SMAP) mission. As well, this research aims, to investigate the spatiotemporal variability of soil moisture in a field-scale area with a particular focus on the analysis of the effect land surface heterogeneity(important over tropical domains) on the retrieval of soil moisture from L-band passive microwave observations. The second and third phases, will expand over phase one and will focus on characterization of crop canopies and water stress related phenomena using microwave remote sensing methods. The results of this research will promote and open new areas research in Puerto Rico (i.e. Unnamed Aerial Vehicle Crop health monitoring). To our knowledge, this study constitutes the first attempt to study, in the Caribbean, the performance of soil moisture retrievals using passive microwave observations form a ground-based L-band radiometer that mimics the upcoming NASA Soil Moisture Active Passive (SMAP) mission that will be launched in January 2015. Moreover, the entire process and results of this research will be integrated into the education process at the Civil Engineering and Surveying Department of the University of Puerto Rico.