IN23A-1072: Life Under Your Feet: A Wireless Soil Ecology Sensor Network

K. Szlavecz1, A. Terzis1, R. Musaloiu1, A. Szalay1, J. Gupchup1, C.-J. Liang1, L. Xia1, J. Cogan1, J. Silverman1, C. Swarth2, S. Matthews2, E. Ellis3

1The Johns Hopkins University 2Jug Bay Wetlands Sanctuary, MD, 3University of Maryland, Baltimore County

Sensor Network TechnologySensor Network Technology

This study was supported by: Microsoft Research, NSF EEC-0540832 (MIRTHE-ERC), NSF DEB-0423976, This study was supported by: Microsoft Research, NSF EEC-0540832 (MIRTHE-ERC), NSF DEB-0423976, DHS N00014-D6-1-0991(PACER) DHS N00014-D6-1-0991(PACER)

• 6-hour data downloads

• Ultra-Efficient data collection protocol (Koala)

• Data Authentication protected using SHA-1

• 2-phase Data Loading Pipeline• Deployment Specific Phase “Stage”• Deployment Independent Phase “Science”

• Health Monitoring Report Generation System

Architecture

Koala

“Koala” is an ultra efficient data retrieval system designed specifically for long term environmental monitoring networks such as ours. Sensor Networks run on a fixed power budget . Koala is specifically optimized to minimize the amount of radio communication thereby minimizing power cost and facilitating periodic data downloads

Data Access

• No Time-Synchronization (save power)

• Measurements as Local Timestamps

• Post Mortem Timestamp Reconstruction

• Algorithm is robust to Mote Reboots, Gateway Failures

Timestamp Reconstruction

• Data available using Microsoft SenseWeb

• Download data from Websitehttp://www.lifeunderyourfeet.org/

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• Per-mille (0.1%) duty-cycles

• Bulk download of data

• Low Power Probing (LPP) : efficient network wake up

• Flexible Control Protocol (FCP) : Network Discovery and download

Jug bay DeploymentJug bay Deployment

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Deployment Details• Period : July 13, 2008 – present• Stations: 19• Location: JHU, Baltimore MD• Sensors• Soil {Temperature, Moisture}• Ambient {Temperature, Light, Humidity}• Vaisala WXT Weather Station

Deployment Details• Period : July 29 – present• Stations: 31• Location: Carney, MD (co-located) near a CO2 flux tower• Sensors• Soil CO2• Soil {Temperature, Moisture}•Ambient {Temperature, Light, Humidity}

Deployment Details• Period : June 25 – Nov 2008• Stations: 7• Location: Jug Bay Wetlands Sanctuary, MD• Sensors:• Soil {Temperature, Moisture}• Ambient {Temperature, Light, Humidity}• Koala and the 2-

phase loading architecture were exhaustively tested in this deployment

• What is the spatial pattern of soil moisture and temperature in different microhabitats?

• Does earthworm distribution reflect this pattern?

Understanding coupled carbon and water cycle in urban ecosystems (The Baltimore Ecosystem Study LTER, www.beslter.org)

The effect of land use, land cover and land management on soil characteristics and soil biogeochemical processes

Motivation

Motivation• Gender of turtles is determined by temperature during incubation of eggs

• Global warming may affect hatching success and sex ratio

• This is part of a larger turtle monitoring study in Maryland

Earthworm Biomass (g/m2)

Earthworm Density (ind/m2)

Soil Temperature Volumetric Soil Water Content

Motivation

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BT1 – Hatched : Sep 27th 2008

RB1 – Hatched : Sep 27th 2008

RB2 – No hatchlings

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BT2 – Hatched : Oct 1st 2008

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