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Note
From the Director
Thank you for
taking the time to read the latest edition of TD News. We have focused
much of our sales and marketing efforts in the past 4 months on
working with our customers to bring real-world examples of Turner
Designs instruments being used for a wide range of applications.
We feel strongly that presenting real-world examples and data is
the most effective marketing strategy for our customer base. We
have highlighted two examples in this Newsletter, however, to view
the complete database please visit the new Turner
Designs Data Bank that can be reached from our homepage. Also,
please contact our sales team (sales@turnerdesigns.com)
if you would like to take part in the Databank Program.
You will also
see an article titled 'History of the 10-AU' that describes the
long history of our flagship instrument. The 10-AU continues to
set the standard in field fluorometry, offering unparalleled versatility
and sensitivity.
I hope you enjoy
this edition of the TD Newsletter. We are always interested in hearing
from you; please do not hesitate to contact us with feedback on
the newsletter or our products and services.
Yours truly,
Rob Ellison
Director of Sales and Marketing
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| New
Employee Announcement |
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 We
are proud to announce the hiring of Chelsea Donovan as Application
Scientist. Chelsea has an extensive background in instrumentation
and the aquatic sciences. Most recently Chelsea spent six years
at the South Florida Management District as an Environmental Scientist
investigating the effects of freshwater inputs into Florida Bay.
Chelsea then spent the past year working for the National Park Service
at Point Reyes National Seashore in California where she focused
on wetland restoration. Chelsea's main responsibilities at Turner
will be in supporting product and application development and serving
as an applications specialist to support customers and our sales
and marketing team. Feel free to contact Chelsea with questions
related to custom products or new applications.
cdonovan@turnerdesigns.com
1(877)316-8049 ext. 148
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Request
A Visit by Turner Designs Factory Personnel |
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 If
you have been waiting for someone from Turner Designs to visit you
personally for any of the following reasons, please contact us to
schedule a visit:
- Show appreciation
for your business
- Assist with
using fluorometers
- Update you
on what's new from Turner Designs
- Demonstrate
a product
- Run a seminar
on Fluorometer Applications
- Provide application
support
- Tell us what
new products you would like to see from Turner Designs
- You just
want to talk with us…..
We're putting
together our travel plans for the next few months, and now is a
good time to tell us when would be your preferred time to visit
you. For more details, and to schedule a visit, please call Patrick
Sanders on 1(877)316-8049 ext. 117, or e-mail your request to: sales@turnerdesigns.com
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| Turner
Designs Announces Applications Databank |
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 Turner
Designs is pleased to announce the launch of their Applications
Databank, a powerful browser tool to provide access to the most
comprehensive and useful database of "real world" applications
provided by customers using Turner Designs fluorometers.
The purpose
of the Databank is to provide prospective customers with the data
they need to make the best purchasing decision, in an unbiased environment.
In addition, it will enable the exchange of information between
customers with ideas on fluorometer applications and results.
The Databank
will be continuously updated with new applications from our customers.
To encourage customers to submit applications, Turner Designs will
offer significant discounts off our products in return for databank
submissions.
To access the
Databank Search page, follow this link:
http://www.turnerdesigns.com/databank.html
Databank
Incentive Details
To encourage our customers to submit applications for publication
on the Databank, Turner Designs will offer customers a discount
on their next purchase. For orders costing more than $4,300, customers
will receive a credit note for $300 good for any future purchase
from Turner Designs. For orders costing less than $4,300, we will
provide a credit note for 7% of the cost of the purchase.
Additional details
on the Application Submission process can be found by following
the "Program and Promotion Details" link on the Databank
homepage, see above.
Use it now!
Check out the existing customer applications on chlorophyll, cyanobacteria
and dye tracing. Consider sending in details on your application
- and enjoy an attractive discount on your next purchase of a Turner
Designs fluorometer.
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| Coming
Soon - Model 200 Display Unit/Datalogger for Cyclops-7 |
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If you own the
Cyclops-7 fluorometer or SCUFA fluorometers, but want an off-the-shelf
companion display unit/data logger, ask for information on the soon
to be announced Turner Designs Model 200 Analog Display Unit.
The Model 200
interfaces to the Cyclops-7 via a 10 ft cable, and provides the
following functions:
- Real Time
Readings using LCD Display, (with backlight)
- Internal
batteries which also power the Cyclops-7
- 1,000 Point
Internal Datalogger
- Data Interface
to PC
- Gain Range
Selection to sensor, (X1, X10 and X100)
The Model 200
is completely self contained and is designed for field use. You
can select to display the sensor output in Volts, µg/L, (chlorophyll
a), or ppb (Rhodamine) in real time. Three averaging modes (Fixed,
Free Running and Moving Average) provide signal processing capability.
For more information
on the Model 200 Display Unit including pricing and availability,
e-mail sales@turnerdesigns.com
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History
of the 10AU
The 10-AU Field
Fluorometer is an instrument that has played a key role in the long
history of Turner Designs and continues to serve the scientific
community as a versatile and reliable workhorse for environmental
fluorescence applications.
 Turner
Designs has a long and sometimes confusing history that stretches
back to the mid 1960’s when our founder, George Turner, sold his
company, Turner Associates, maker of the Turner 110 and 111 Filter
Fluorometers. Often referred to as ‘The Green Box’ the Turner 110
was a great success as a sensitive laboratory instrument and an
important tool in the development of extracted and in vivo chlorophyll
detection methodology. The drawbacks of these vacuum tube instruments
were that they could not easily be used in remote field stations,
on-ships or other outdoor sites due to the high power requirements
and exposed electronics. With the new owners of Turner Associates
unwilling to invest into the development of a true field instrument,
George Turner left the company to found his second company, Turner
Designs.
 The
newly formed Turner Designs embarked on an ambitious project to
build the first truly field-ready fluorometer and developed the
Model 10 in the early 1970s, an extremely durable, sensitive and
stable analog instrument. They succeeded and developed an instrument
that was water-tight, consumed less power, accepted flowcells or
discrete samples and most importantly maintained calibration even
in the most extreme conditions. The instruments are so durable that
customers will often ship them to Turner Designs for servicing without
a box and tape shipping labels directly to the instrument (Turner
does not advocate this activity!). To this day there are 100’s of
Model 10s still working around the globe with owners who cherish
them like they would a classic car. The Model 10 has come a long
way since the early 70s but the qualities that made it such a trusted
and beloved instrument are still present and make it a truly unique
product.
 The
modern incarnation of the Model 10 is the 10-AU-005-CE and exhibits
all the qualities that made the Model 10 so popular with the addition
of modern conveniences such as automatic range control, temperature
compensation, internal data logging, digital output, calibration
and diagnostics saved to memory, etc.. The 10-AU-005-CE continues
to be the field fluorometer of choice. As an example, the US E.P.A.
has just released a new report titled, Rapid Processing of Turner
Designs Model 10-AU-005 Internally Logged Fluorescence Data (EPA/600/R-04/053,
August 2004) on the use of the 10-AU for dye tracing applications.
If you are interested in a filter fluorometer that can be used for
any application or environment and that will last a career; the
10-AU is for you.
For examples
of how the 10-AU is used by scientists today please visit the Turner
Designs DataBank.
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 Model
10-AU Standard Curve
Question:
We are preparing
to do a dispersion study in a river, using Rhodamine WT dye and
a Model 10-AU Fluorometer set up in the Flow through mode. The client
has specified that a "multi-point" calibration should
be performed on the Fluorometer. Since the Model 10-AU calibration
consists of one Standard point and a Blanking point, how can I satisfy
the multi-point requirement?
Answer:
The multi-point
requirement can be accomplished by creating a series of standard
sample concentrations of the Rhodamine WT dye. Perform the blanking
and single point calibration on the 10-AU using a standard concentration
between 20 and 100 ppb (ug/L). Then read the series of standard
samples and construct a "standard curve". The standard
curve will demonstrate that the 10-AU is producing a linear correlation
for the series of standard sample concentrations that are below
100 ppb.
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 Technically
Speaking, It All Adds Up…….
is a series
of articles for people who want to obtain the best possible results
from their fluorometer. This month's article will describe some
good measurement practices to produce consistent and reliable readings
when using submersible fluorometers in the lab. The effects of sensor
positioning, optimum bench top characteristics, etc will be described.
The principles apply to all submersible fluorometers when used for
making lab measurements.
Introduction:
While many applications for fluorometers require only monitoring
for changes in concentration, when absolute concentration values
are required, the fluorometer, or the solution, needs to be referenced
to a standard.
Turner Designs
sells Primary Standards for chlorophyll a measurements and Solid
Secondary Standards for use with all Turner fluorometers and flourophores
such as chlorophyll a, cyanobacteria, CDOM, fluorescein, etc., see
Figures 1 & 2.
For extracted
chlorophyll measurements using discrete sample fluorometers, Turner
Designs Primary Standard for chlorophyll measurements consists of
pure chlorophyll a prepared in 90% acetone. The standard is supplied
with calibration certificates for two accurately known concentrations,
a precise high value around 150 µg/L (high), and a precise
low value around 15 µg/L, (exact values are provided).
Figure 1: Turner Designs Chlorophyll a
Primary Standards are sold in 20 mL ampoules for the high and low
values.
Note that Extracted
Chlorophyll a Primary Standards should not be considered as direct
primary standards for in-vivo chlorophyll measurements, because
for in-vivo measurements, the chlorophyll is contained inside the
living algal cell. When performing in-vivo sampling, using Solid
Secondary Standards is the most convenient approach for calibrating.
Then, when you extract samples, you will determine the correlation
of the Solid Secondary Standard for a given "in-vivo"
Chlor a concentration, visit our web site for more details.
For dye trace
measurements, Primary standards are normally made from the same
dye that is being used for the study. Typically these Primary standards
are made to concentrations of 100 PPB or lower. Turner Designs sells
Rhodamine WT dye, as a liquid of 21% active ingredient. Visit our
web site for more details.
Turner Designs
Solid Secondary Standards are Secondary because they are not the
same solution as the fluorophore being measured. They are made from
a very stable fluorescent material making them ideal for validating
fluorometer calibration.
Figure
2: Selection of Solid Secondary Standards, note the SCUFA and Aquafluor
standards are adjustable.
Some other advantages
of the Solid Secondary Standard are:
- Very high
stability. The signal is extremely stable over time, (years).
- Easily adjusted
to provide a stable desired equivalent concentration value
- Low total
cost of ownership - break even point is around 2 sets of chlorophyll
standard.
- No solutions
to mix, store carefully, run out, spill, etc.
- Easily used
in the field and other "non-lab" environments.
- Check for
loss of sensitivity resulting from the growth of bio-fouling organisms
on the sensor optics.
Using Solid
Secondary Standards:
Solid Secondary Standards are very easy to use because all that
is required is to insert the standard into the fluorometer and note/set
the reading. At a subsequent time, the standard is reinserted to
the fluorometer, and any variation in reading is then applied to
the fluorometer sample readings.
Good Operating
Practices :
The Solid Standard should be treated as any other precision standard.
It should be kept in a box when not in use. This will minimize the
collection of dust on the exposed section of fluorescent material.
In the event
that dust is present on the fluorescent material, it should be removed
with one of the aerosol can dust removers.
It is possible
for humidity to effect the performance of the Secondary Standard.
To avoid/minimize this, it is suggested that the Solid Secondary
Standard is kept in a ZipLoc bag with some desiccant bags.
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Detecting
Filamentous Cyanobacteria Blooms in the Baltic Sea Using
Turner Designs Model 10-AU Fluorometer
About
The Finnish Institute of Marine Research
The Finnish Institute of Marine Research (FIMR, http://www.fimr.fi/en.html)
is a government-funded institution under the Ministry of
Transport and Communications. FIMR is a multidisciplinary
research institution carrying out basic research and providing
services in the fields of physical, chemical and biological
oceanography. The activities are mainly focused on the Baltic
Sea. FIMR employs approximately 120 people, about half of
them are directly involved in research activities.
Harmful
cyanobacteria blooms in the Baltic Sea
The Baltic Sea, in the northern Europe, is surrounded by
9 countries and approximately 85 million people live in
its catchment area. Ecologically the Baltic, which is the
second biggest brackish water basin in the world, is unique.
Since the last ice-age this basin has succession from lake
to brackish sea, nowadays the salinity varies from 20 PSU
in southern basin to near zero values in the Bothnian Bay
in north. The low salinity, together with ice winters, largely
affects the distribution of aquatic flora and fauna in the
Baltic.
Seasonality,
with varying colors, in the open sea phytoplankton community
can be perceived even by casual observer. Spring bloom with
brownish colored diatoms and dinoflagellates is followed
by clear water season in mid-summer. Towards the end of
summer some locations suffer from frequent cyanobacterial
blooms, with turquoise or green to yellow colors. In calm
and warm days in the June-August, one can observe kilometer-wide
pea soup-like surface accumulations of filamentous cyanobacteria.
These summer blooms of nitrogen-fixing filamentous cyanobacteria,
with main species Nodularia spumigena, Aphanizomenon sp,
and Anabaena spp., counteract the reduction of anthropogenic
nitrogen load, have possible toxic effects for the other
components of the ecosystem and thereby may lower the value
of fisheries, and affect the recreational use of coastal
area. The intensity of these blooms is related to low inorganic
N:P ratio, high temperature of surface waters, and low wind
mixing.
Photo
1: Aimar Rakko from University of Tartu taking sample of
filamentous cyanobacteria in a traditional way
To find
out the triggering factors for these blooms and to analyze
their environmental consequences, and thereby supporting
science based management of the Baltic Sea, phytoplankton
dynamics must be studied with the relevant spatial and temporal
resolution. For this task, in FIMR the traditional methods
for phytoplankton studies have been supplemented with automated
detection systems placed on ships of opportunity, and with
satellite data. In the Baltic Sea, the Alg@line system (www.balticseaportal.fi),
coordinated by FIMR, for the detection of phytoplankton
biomass by fluorescence has been running for ten years.
Alg@line utilizes merchant ships and ships of Finnish coastal
guard. Currently 9 vessels have flow-through fluorometers
and thermosalinographs operating, providing approximately
1.5 - 2 million observation per year.
Phycobilin
fluorescence as a tool for cyanobacteria detection
Chlorophyll in vivo fluorescence is, however, not optimal
for the detection of cyanobacteria as for these species
fluorescence at the wavelengths specific for chlorophyll
is very weak. Instead, these species contain phycobilin
pigments that have their own specific wavelengths for excitation
and fluorescence emission.
Our
previous studies with pure phytoplankton cultures and experimental
work in field has provided important background for cyanobacterial
detection by fluorescence. We have noted that bloom forming
filamentous species in the Baltic are the main source of
phycocyanin related optical signals. Picocyanobacteria (i.e.
cells <2µm), not forming the blooms, together with
some eucaryotic species, is the main source of phycoerythrin
signals. Studies with cultures provide us also information
on the environmental control of the variability in cellular
phycobilin content. That is extremely significant information
when analyzing the field data.
Already
20 - 30 years ago it was suggested that phycobilin fluorescence
could be used to estimate cyanobacterial distribution -
and since that we have made some attempts in the Baltic
Sea as well. Now, our aim in Alg@line is to start operational
detection of phycocyanin in Baltic by summer 2005.
During
EU-funded project FERRYBOX (http://www.ferrybox.org)
we have conducted vigorous laboratory tests with Turner
10-AU fluorometer with phycocyanin kit (excitation 620 nm,
emission 650 nm), and we have verified that the sensitivity
and linear range are suitable for detection of natural concentrations
of filamentous cyanobacteria. As well we have noted the
high specificity of instrument; the effects of light scattering
and overlapping fluorescence from dissolved matter and other
pigments are negligible. Phycocyanin fluorescence readings
are further normalized to known concentrations of commercially
available C-phycocyanin in buffer, as the actual in vitro
phycobilin concentration measurements are hard to perform
from discrete water samples.
Figure 1: Excitation - emission
matrix for colored dissolved organic matter (CDOM), and
for cultured green algae with high chlorophyll a fluorescence
and filamentous cyanobacteria with high phycocyanin fluorescence.
Steps
towards operational use of phycocyanin fluorescence
In pre-operational testing phase in summer 2004, we used
phycocyanin fluorometer during cruises of RV Aranda. It
was operated in flow-through mode together with two fluorometers
for chlorophyll detection (10AU and CYCLOPS-7), and flow-through
spectrofluorometer. Discrete samples were taken from water
flow to determine pigment concentrations, count phytoplankton
cells and to measure the light absorption by phytoplankton.
Yet these data are not fully available. More data is needed,
but our objective is to obtain estimates on the variability
in cyanobacterial biomass and pigment specific fluorescence
intensities for calibration purposes of phycocyanin fluorometer.
Photo
2: Pasi Ylöstalo and a set of Turner fluorometers in
RV Aranda
As an
example of data collected thus far, the grid recorded in
July 26-27, 2004 in the Gulf of Finland, Baltic Sea, shows
clearly the location of cyanobacterial bloom batches, with
high phycocyanin fluorescence, in the middle cruise grid.
The locations of these high phycocyanin areas are identical
to visual observations of bloom areas. Clearly, phycocyanin
and chlorophyll fluorescence were not directly related.
Obviously, chlorophyll measured by in vivo fluorescence
mainly reflects the eucaryotic part of the phytoplankton
community while phycocyanin reflects only filamentous cyanobacteria
in our study area.
Figure 2: Spatial variability of
Chlorophyll a concentration, phycocyanin fluorescence and
their ratio as estimated by two Turner AU-10 fluorometers
during a bloom of filamentous cyanobacteria, July 26 - 27,
2004 in the Gulf of Finland, Baltic Sea.
Next
steps in our phycocyanin fluorescence research includes
evaluation of Cyclops 7 phycocyanin fluorometer, and installation
of one phycocyanin fluorometer for operational use in 2005.
Then the seasonal phycocyanin profiles across the Baltic
Sea will be used in evaluation of bloom development, to
assist selection of sampling sites for dedicated cyanobacterial
research, in validation of ecosystem models, and in validation
of ocean color data for cyanobacterial distribution.
Study
group
Other scientist directly involved in phycocyanin related
studies in FIMR are Pasi Ylöstalo (instrument testing,
phytoplankton physiology), Seppo Kaitala (satellite images,
Ferrybox systems), Mika Raateoja (Alg@line coordinator,
phytoplankton physiology). Additional information is available
from Jukka Seppälä, Finnish Institute of Marine
Research, P.O. Box 33, FIN-00931 Helsinki, Finland, jukka.seppala@fimr.fi
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Integrating
GIS and fluorometry for real-time mapping of coastal systems
About
Cawthron Institute
Cawthron Institute provides science and technology solutions
to enable the sustainable management and development of
New Zealand's coastal and freshwater resources for the benefit
of the region and the nation. Cawthron has been operating
in Nelson, New Zealand for over 80 years and is owned by
a trust that represents the local community and employs
over 150 scientific and technical staff.
Within
Cawthron, the Coastal Group provides expert scientific advice
in both commercial and research settings in the fields of
resource management, coastal ecology, fisheries and aquaculture
sustainability, environmental effects of waste discharges
and oil spills, biosecurity and environmental modelling.
Overview
This article focuses on our integration of the 10-AU and
SCUFA fluorometers with desktop Geographical Information
System (GIS) software for real-time mapping and data collection.
To demonstrate this, we have highlighted two case studies:
(i) tracking effluent dispersion/dilution from coastal outfall
(using Rhodamine® WT dye) and (ii) mapping chlorophyll-a
depletion around marine mussel farms.
The
Monitoring Dilemma
While monitoring dye in effluent plumes or in-situ chlorophyll-a
using fluorometers is by no means new, one of the biggest
dilemmas is incorporating the data collected with positional
data to create maps and/or charts. Historically, this was
done in the field by writing down position and fluorescence
readings or entering them into a laptop. However, manual
data collection can be both tedious and fraught with potential
transcription errors.
The
change from analog to digital instruments has greatly enhanced
the ability to collect and log fluorescence data, but that's
only half the story, since position data are also required.
The advent of Global Positioning Systems (GPS), and the
subsequent removal of selective availability, has meant
that accurate (i.e. ± 2-5 m) real-time position data
are now both readily available and affordable. Also, along
with the improvements in instrumentation, the ability to
run desktop GIS has been rapidly improving. Therefore, in
order to create real-time maps, these three components:
GPS, GIS, and fluorometry need to be combined.
The
Solution
Cawthron has created a custom add-on to Arcview ® 8.3
GIS that connects to the different simultaneous serial data
streams of the instrumentation in the field (i.e. GPS, SCUFA,
10-AU), combines the incoming data and maps the fluorescence
in real-time as graduated dots. The fluorescence data are
overlaid on a rectified nautical chart or aerial photograph
so that the actual position of each fluorescence reading
in relation to the area being studied (e.g. outfall or mussel
farm) can be determined. This approach has numerous benefits,
including the ease of use, time-saving, the ability to collect
large amounts of data, and the ability to view and make
decisions in the field regarding the data collected.
The
Arcview® add-on was written in Visual Basic for Applications
(VBA®) and enables the user to select which serial port
the instruments are connected to (Figure 1), the frequency
with which data are to be collected (the capture interval)
and the file name to log the data to. In addition, there
is a real-time window that displays current position and
fluorescence.
Figure
1. Screen shot of Arcview® serial data capture form.
Once
a connection is made the incoming data are parsed into individual
variables. For general monitoring, much of the GPS data
is extraneous and just the position and time data are required.
This includes Latitude, Longitude, Speed, Direction, and
Time. Therefore, only certain GPS sentences are used in
the add-on and are converted on the fly to local New Zealand
Map Grid coordinates. All GPS and fluorometric data are
parsed and logged in Arcview® as individual fields within
a shapefile.
Case Study 1: Mapping Dye from a Coastal Outfall using
a 10-AU Fluorometer
This integrated logging system was used for a recent study
on the south coast of New Zealand's North Island, to study
dye dispersion from a nearshore coastal outfall discharging
tertiary treated wastewater.
Rhodamine®
WT dye was injected into the wastewater at a constant rate
(Figure 2) and effluent dilution and dispersion were mapped
on both an ebb and flood tide. Continuous fluorescence readings
were taken from a vessel using a 10-AU field fluorometer
set up for flow-through measurements and linked to a portable
PC and GPS. Data were collected by running a series of transects
through the effluent plume both perpendicular to and along
the effluent plume path. To verify effluent concentrations,
grab samples were collected every 15 minutes using a sequential
autosampler positioned downstream of the injection point.
Figure 2. Configuration of dye
injection system in relation to autosampler and outfall.
A screen
shot of the 4,300 data points collected on the four hour
ebb tide study is presented in Figure 3. Receiving water
dilutions of each data point were calculated from the effluent
concentrations measured in the grab samples. Contours of
these dilution factors were manually digitized using the
GIS software to better illustrate the dispersion and dilution
pattern of the effluent (Figure 4).
Figure
3. Graduated symbols of all data points collected for mapping
dye dilution/dispersion.
Figure
4. Post-generated dilution contours of ebb tide data points.
Case
Study 2: Mapping chlorophyll-a around a mussel farm
Another example of the application of this integrated GIS-fluorometry
system is the real-time mapping of chlorophyll-a depletion
around coastal mussel farms. In order to assess the sustainability
of mussel farms around New Zealand's coast, the concentrations
of chlorophyll-a (which represents phytoplankton) are measured
at 3m (i.e. the active feeding depth) and incorporated into
modelled predictions of sustainability. This information
can then also be used by the farmer to optimise farm management.
The
SCUFA can be employed in a similar way to the 10-AU in outfall
dye studies, providing continuous measurements of chlorophyll-a
(post-calibrated) through and around mussel farms (Figure
5). Typically, currents are also collected simultaneously
with the GPS positions and fluorometry data, to give insight
into the patterns of water movement around the farms.
In the
example below (Figure 5), two synoptic snap-shots were taken
in a bay containing four small farms (delineated by black
dotted lines). The data were then plotted in 2-dimensional
colour contours using an appropriate interpolation method.
Depletion areas (blue regions) are evident in the vicinity
of the farms, allowing the magnitude of depletion to be
assessed and the behaviour of the water through the bay
to be observed. The results are then compared against outputs
from various models to improve our confidence in their predictive
capabilities.
Figure 5. Subsurface (3m) contours
of Chlorophyll-a concentration in the vicinity of four mussel
farms under two different tidal states.
Conclusion:
Cawthron's integration of Turner fluorometers with GPS and
GIS for real-time mapping has had major benefits in the
way we use these instruments. The efficiency with which
data are collected ensures research is conducted in a cost
effective manner. Further, field data can be tracked visually
and any anomalies in spatial distribution are immediately
apparent. This helps ensure data validation and overall
data integrity.
For
details on this and/or other capabilities that Cawthron
offers, please contact Paul Barter (paul.barter@cawthron.org.nz)
or:
 Cawthron
Institute
98 Halifax Street East
Nelson, New Zealand
www.cawthron.org.nz
info@cawthron.org.nz
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