An interoperable wireless sensor network platform for spatio-temporal soil moisture and soil temperature estimation

Spatio-temporal root zone soil moisture (STRZSM) plays a vital role in the understanding of land-surface dynamics, climate change, soil-water-balance, hydrologic processes, vegetation growth and yield modeling. STRZSM trails can be captured using remote sensing, in-situ or ground based measurements or through land surface models. Apart from this, new generation of low-cost soil moisture sensors present cost effective way of in-situ measurement of soil moisture, but suffer from inherent heterogeneity between sensing techniques, protocol variations and non-standard calibration methods. Thus, long term monitoring of spatial and temporal variations in soil moisture trails requires interoperability between sensing platforms, process-based and statistical modeling and inclusion of remote sensing techniques. In this study, an attempt has been made to design and deploy an interoperable sensing platform that complies with Open Geospatial Consortium (OGC) Sensor Web Enablement (SWE) framework. Proposed system uses sensors to estimate point-based soil moisture and temperature observation at different depths of 15, 30, 45 and 60cm each. Pilot feasibility study was carried out for the duration of three months from Jan-Mar 2016 in the study area. The results include visualizations for soil moisture and soil temperature profiles at different depths over the period of three months. This study also explores the possibility of deploying dense interoperable sensor networks to capture spatio-temporal variability of soil moisture over heterogeneous landscapes.