Life Under Your Feet: A Wireless Soil Ecology Sensor Network

Abstract

Wireless sensor networks can revolutionize soil ecology by providing measurements at temporal and spatial granularities previously impossible. This paper presents an experimental soil monitoring network that we developed and deployed in a Baltimore urban forest as a first step towards realizing this vision. Each network node measures soil moisture and temperature every minute and stores the measurements in local memory. Raw measurements are periodically retrieved by a sensor gateway and inserted to a database in which a calibrated version is also derived and stored. At a high level, this was a successful test deployment exposing high level variations of soil factors. However, we encountered a number of challenging technical problems: need for low-level programming at multiple levels, calibration across space and time, and cross-reference of measurements with external sources. These problems must be addressed before sensor networks can fulfill their potential as experimental instruments that can be deployed by scientists without major effort or cost.