A Networked Sensor System for the Analysis of Plot-Scale Hydrology

German Villalba; Fernando Plaza; Xiaoyang Zhong; Tyler W Davis; Miguel Navarro; Yimei Li; Thomas A Slater; Yao Liang; Xu Liang

doi:10.3390/s17030636

A Networked Sensor System for the Analysis of Plot-Scale Hydrology

Sensors (Basel). 2017 Mar 20;17(3):636. doi: 10.3390/s17030636.

Authors

German Villalba¹, Fernando Plaza², Xiaoyang Zhong³, Tyler W Davis^{4

5}, Miguel Navarro⁶, Yimei Li⁷, Thomas A Slater⁸, Yao Liang⁹, Xu Liang¹⁰

Affiliations

¹ Department of Civil and Environmental Engineering, University of Pittsburgh, 3700 O'Hara Street, 728 Benedum Engineering Hall, Pittsburgh, PA 15261, USA. gev5@pitt.edu.
² Department of Civil and Environmental Engineering, University of Pittsburgh, 3700 O'Hara Street, 728 Benedum Engineering Hall, Pittsburgh, PA 15261, USA. fjp9@pitt.edu.
³ Department of Computer and Information Science, Indiana University Purdue University, 723 West Michigan Street, SL 280, Indianapolis, IN 46202, USA. xiaozhon@umail.iu.edu.
⁴ Department of Civil and Environmental Engineering, University of Pittsburgh, 3700 O'Hara Street, 728 Benedum Engineering Hall, Pittsburgh, PA 15261, USA. twd34@cornell.edu.
⁵ Currently at USDA-ARS, Robert W. Holley Center for Agriculture and Health, 538 Tower Road, Ithaca, NY 14853, USA. twd34@cornell.edu.
⁶ Department of Computer and Information Science, Indiana University Purdue University, 723 West Michigan Street, SL 280, Indianapolis, IN 46202, USA. mignavar@iupui.edu.
⁷ Department of Computer and Information Science, Indiana University Purdue University, 723 West Michigan Street, SL 280, Indianapolis, IN 46202, USA. liyim@imail.iu.edu.
⁸ Department of Civil and Environmental Engineering, University of Pittsburgh, 3700 O'Hara Street, 728 Benedum Engineering Hall, Pittsburgh, PA 15261, USA. tas186@pitt.edu.
⁹ Department of Computer and Information Science, Indiana University Purdue University, 723 West Michigan Street, SL 280, Indianapolis, IN 46202, USA. yaoliang@iupui.edu.
¹⁰ Department of Civil and Environmental Engineering, University of Pittsburgh, 3700 O'Hara Street, 728 Benedum Engineering Hall, Pittsburgh, PA 15261, USA. xuliang@pitt.edu.

Abstract

This study presents the latest updates to the Audubon Society of Western Pennsylvania (ASWP) testbed, a $50,000 USD, 104-node outdoor multi-hop wireless sensor network (WSN). The network collects environmental data from over 240 sensors, including the EC-5, MPS-1 and MPS-2 soil moisture and soil water potential sensors and self-made sap flow sensors, across a heterogeneous deployment comprised of MICAz, IRIS and TelosB wireless motes. A low-cost sensor board and software driver was developed for communicating with the analog and digital sensors. Innovative techniques (e.g., balanced energy efficient routing and heterogeneous over-the-air mote reprogramming) maintained high success rates (>96%) and enabled effective software updating, throughout the large-scale heterogeneous WSN. The edaphic properties monitored by the network showed strong agreement with data logger measurements and were fitted to pedotransfer functions for estimating local soil hydraulic properties. Furthermore, sap flow measurements, scaled to tree stand transpiration, were found to be at or below potential evapotranspiration estimates. While outdoor WSNs still present numerous challenges, the ASWP testbed proves to be an effective and (relatively) low-cost environmental monitoring solution and represents a step towards developing a platform for monitoring and quantifying statistically relevant environmental parameters from large-scale network deployments.

Keywords: MPS-2 sensor; TelosB mote; environment sensors; outdoor deployment; sap flow; sensor board; soil moisture; soil water potential; wireless sensor network.