TEOS GroupTEOS Group

MENTOR: Eric Graham

INTERNS:

Martin Gawecki Kathlyn Bland Devin Sevilla

The The Wonderful Wonderful World of World of Bracken Bracken Ferns…Ferns…

Or is it???Or is it???

By Kathlyn Bland

Step into my office…

Why should we study theWhy should we study theBracken Fern?Bracken Fern?

•The Bracken Fern is a worldwide pest which poses many health and agricultural problems for society.

•Learning more about how this plant responds to changes in its microenvironment, will teach us something about our environment as a whole.

•The more we know about our environment, the better prepared wewill be to react and make wise decisionson how to improve and maintain ournatural surroundings.

What types of data will be collected?What types of data will be collected?The machine we use to collect data is called the LI-COR 6400. Basically, the “Cadillac” of photosynthetic measurements.

It collects several different pieces of data…•CO2 Analyzer •Air Flow•Temperature•Light

Sample is 3 cm X 2 cm

This is my $30,000 baby!

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•Constant CO2 level equal to 400µmol/L•10 minutes shade with 20µmol of light•Then we raised the light level to 750µmol of light

Conductance VS TimeConductance VS Time

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•Conductance is a measurement of the rate which water vapor or CO2 travels across the stomata (basically small pores) of the plant.

•You can see that once we increased the light available for photosynthesis, the plant started to increase the rate in which water and CO2 passed through the stomata, thus they open quite a bit when exposed to full light.

A/CA/Cii Curves CurvesShade Medium Shade

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•Relationship between photosynthetic rate and intercellular CO2 concentrations•Blue line represents changing CO2 reference level•Pink line represents the induction curve•This relationship allows us to make conclusions about how gas exchange occurs and how the plant responds changes in its enviornment

Shading ExperimentShading Experiment

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GoalsGoals

• We would like to collect enough data to We would like to collect enough data to publish a scientific manuscript by the end of publish a scientific manuscript by the end of Fall 2006.Fall 2006.

• My main goal is to learn about CENS My main goal is to learn about CENS technology from my peers and how it applies technology from my peers and how it applies to the biological sciences.to the biological sciences.

Infrared Gas Infrared Gas Sampling for Sampling for

Terrestrial Carbon Terrestrial Carbon Dioxide and Water Dioxide and Water

Vapor Concentration Vapor Concentration GradientsGradients

Presented By:Presented By:Devin Sevilla and Martin Devin Sevilla and Martin

GaweckiGawecki

Problem StatementProblem Statement

Determine the concentration of CODetermine the concentration of CO22 and Hand H22O vapor in a terrestrial O vapor in a terrestrial environment at 6-8 different altitudes environment at 6-8 different altitudes

Sampling can take place during the Sampling can take place during the day or night day or night nighttime sampling is preferable because nighttime sampling is preferable because

of less wind-driven gas mixingof less wind-driven gas mixing Sampling must be automated and Sampling must be automated and

performed at pre-specified intervalsperformed at pre-specified intervals

Design ApproachDesign Approach HardwareHardware

Infrared Gas Analyzer (IRGA)Infrared Gas Analyzer (IRGA) Mechanical SolenoidsMechanical Solenoids Serial-controlled Relay BoardSerial-controlled Relay Board

SoftwareSoftware Written in C on LinuxWritten in C on Linux Software contains 3 components:Software contains 3 components:

IRGA controllerIRGA controller Relay Board controllerRelay Board controller Master timed controllerMaster timed controller

Experimental SetupExperimental Setup

Mass Flow Meter

Pump IRGA

Solenoids

Controlling Laptop

Relay Board

Solenoids

Experimental SetupExperimental Setup

Experimental SetupExperimental Setup

IRGA COIRGA CO22 Response (Short Response (Short Term)Term)

IRGA COIRGA CO22 Response (Long Response (Long Term)Term)

IRGA HIRGA H22O Response (Short O Response (Short Term)Term)

IRGA HIRGA H22O Response (Long O Response (Long Term)Term)

Sample Data (COSample Data (CO22))

Sample Data (HSample Data (H22O)O)

Preliminary ConclusionsPreliminary Conclusions

Sampling Time – propagation of signal takes:Sampling Time – propagation of signal takes: Approx 40/50 sec (rise and fall) for COApprox 40/50 sec (rise and fall) for CO22

Approx 80/240 sec for HApprox 80/240 sec for H22O (rise and fall)O (rise and fall) Therefore, a “good” sampling time is 5 minutes.Therefore, a “good” sampling time is 5 minutes.

Serial Port Configuration is difficultSerial Port Configuration is difficult Encountered power consumption problemEncountered power consumption problem

Future WorkFuture Work

Adaptive SamplingAdaptive Sampling More Tubes = More LevelsMore Tubes = More Levels Lower Power ConsumptionLower Power Consumption

Better SolenoidsBetter Solenoids Smaller PumpsSmaller Pumps

Compact SizeCompact Size Increased Mobility & ModularityIncreased Mobility & Modularity

AcknowledgementsAcknowledgements

Eric Graham – for always being Eric Graham – for always being there there

Eleanor Lee – for using her cameraEleanor Lee – for using her camera Eric Yuen – troubleshootingEric Yuen – troubleshooting The Dumpster – for things to mount The Dumpster – for things to mount

our prototype onour prototype on