Quality Control of Phycoerythrin Data from The Columbia River Estuary
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Transcript of Quality Control of Phycoerythrin Data from The Columbia River Estuary
1Quality Control of
Phycoerythrin Data from The Columbia River Estuary
Development of a Correction for Turbidity Artifacts.
Observation ● Prediction ● Analysis ● Collaboration
www.stccmop.org
Sarah Riseman
Acknowldegements:
Antonio BaptistaCharles Seaton
Needoba/Peterson LabLydie Herfort
CMOP Field TeamCMOP Staff
2Background: phycoerythrin
• Chemotaxonomic pigment– Synechococcus spp.– Cryptophytes– Myrionecta rubra**
• Measured using Fluoromtry– Autofluorescent: fluorometers designed with filter sets to
specifically measure the presence of phycoerythrin
– Turbidity & temperature are two sources of bias of in situ fluorometric measurements
3Background: Basics of a Filter Fluorometer
Adapted from:http://www.turnerdesigns.com/t2/doc/appnotes/998_0050/0050_c3.html
4Chlorophyll & Phycoerythrin Spectral Properties
Chlorophyll a
Phycoerythrin
460
523
620 - 715
578
5SATURN-03 Data from 2m (July 2010 – March 2011)
Turbidity
Chlorophyll
Raw Phycoerythrin
6Combined Turbidity Correction
Turbidity
Chlorophyll
Corrected Phycoerythrin
7Preliminary Turbidity Correction
AugustJuly September
*NovemberOctober
Monthly Phycoerythrin vs. Turbidity, Colored by Chlorophyll Saturn03 - 2m
Turbidity
Phyc
oery
thrin
8Preliminary Turbidity Correction
combined remainder of data into single data set
time period not usedin regression(8/15 – 10/10)
Time
9Preliminary Turbidity Correction – Linear Fits
Low (< 225ntu)
high(225-500ntu)All Data
10Preliminary Turbidity Correction
11Preliminary Turbidity Correction
back
Turbidity
Corrected Phycoerythrin
Chlorophyll
12Combined Turbidity Correction
Turbidity
Chlorophyll
Raw Phycoerythrin
13New Turbidity Correction
14Details of Correction Determination
Simple Exonent: 3Pf = y0+a*(1-b^x)
r2 = 0.9984
Turbidity0 200 400 600
Phyc
oery
thrin
0.0
2.0e+4
4.0e+4
6.0e+4
8.0e+4
1.0e+5
1.2e+5
1.4e+5
1.6e+5
1. Data Selection: - winter only- all 3 depths- chlorophyll < 2 ug/L- turbidity < 625 NTU
2. Data Binned & Averaged- 1 NTU turbidity bins - data within mean +/- 3 s.d. averaged
3. Curve Fitted- several evaluated- simplest selected: - Exponential rise to maximum:
Single 3 parameter Exponent
15New Turbidity Correction
Corrected Phycoerythrin
Turbidity
Chlorophyll
16Comparison of Turbidity Corrections
17Conclusions
• The turbidity corrections need to be periodically evaluated for changes and updated accordingly
• With correction, the phycoerythrin data display a clear pattern corresponding to Chlorophyll
• These data clearly identified the onset of the 2010 M. rubra bloom
• With field samples a calibration to cell abundance should be possible
18Discussion Topics: where do we go from here?
• Are the corrected data useful?
- Can they be used to monitor the onset & development of M. rubra blooms in the CRE?
• How do we validate these signals?
- field sampling sampling
- monitoring sensor drift
19
• EXTRA SLIDES FOLLOW
20
21Phycoerythrin/Turbidity Relationship Over Time
RE-PLAY
JULYAUGUSTSEPTEMBEROCTOBERNOVEMBERDECEMBERJANUARYFEBRUARYMARCHJULY 2010 – MARCH 2011
22Processing of SATURN-03 Data
23Preliminary Correction
24Turbidity
Chlorophyll
Phycoerythrin - raw
25Turbidity
Chlorophyll
Phycoerythrin - corrected
26Phycoerythrin - corrected
Salinity
27Saturn01 Turbidity Correction based compiled data from 3 depths (2m,8m,13m) where chl < 1.5 ug/L during Aug 4 – Aug 22, 2010)
Saturn01 Turbidity FactorBased on Bin/Avg Regression:
TF = 1178.4*turb + 1334.1
Corrected PE = PE – TF(+2850 to raise to raw data baseline)
28Sat01 -2m PE Correction