Water quality - Wellesley College

Lake Waban: Water Quality
Shoot the Messenger:
Phytoplankton are both indicators and causes
of poor water quality
Lake Waban: Water Quality
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Eutrophic
1994: Pavla Zakova
“Cultural Eutrophication”
Carlson TSI: >50
Excess phosphorus among major
water pollutants
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Inorganic chemicals
Organic chemicals
Sediment
Radioactive materials
Thermal pollution
Infectious agents
Oxygen-demanding wastes
Plant nutrients: water soluble compounds containing
nitrate, phosphate, and ammonium ions
– Human sources: sewage, manure, and runoff of
agricultural and urban fertilizers
Source: Revenga et al. 2000
Original/Actual Design
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Original:
– Tracing the phosphorus pollution to primary
sources
– Fertilizers Algal blooms in Lake Waban
– Curtail the use of fertilizers
Actual
– determine Lake Waban’s water quality
– preventative measures Wellesley College could
take
Total Phosphorus
Source: Zakova 1994
Phytoplankton
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microscopic, photosynthetic plants and some
species of bacteria.
Green Algae, Diatoms, Euglenoids
Cyanobacteria
Algal Blooms
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overabundance of nutrients.
Eutrophication  Blooms
Phosphate levels of 0.03-0.1 mg/L of water
will trigger a bloom
Life: Block sunlight, kill plants
Death  Deplete DO
Algal Blooms
Source: http://www.agr.gc.ca/pfra/water/algcyano_e.htm
Cyanobacteria: Oscillatoria
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second most tolerant of organic pollution
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Thrive in the phosphate-rich lake waters
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Phosphorus limit growth limit
Oscillatoria
Green Algae: Spirogyra
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Grassy odor
Source: http://www.microscopy-uk.org.uk/mag/indexmag.html?http://www.microscopy-uk.org.uk/mag/artjan99/gyra.html
Spirogyra
Source: http://www.biologie.uni-hamburg.de/b-online/library/webb/BOT311/Chlorophyta/SpirogyraBig500.jpg
Diatoms: Navicula, Tabellaria, and
Fragilaria
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Clean: low populations of many different
species of diatoms.
Polluted: the variety of diatoms decreases;
pollution tolerant types increases
Tabellaria: taste and odor
Fragilaria
Navicula: among most pollutant tolerant
Tabellaria
Source: http://www.micrographia.com/specbiol/alg/diato/diat0200/tabell02.htm
Fragilaria
Source: http://www.ci.austin.tx.us/watershed/publications/files/sr0408_evalalgaebloom.pdf
Navicula
Source: http://www.micrographia.com/specbiol/alg/diato/diat0100/navicu00.htm
Euglenoids: Euglena
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the most tolerant
genus of organic
pollution.
Protozoan: Paramecium
Indicators of Water quality
Clean Water
Polluted Water
Taste and Odor
Surirella
Chlorella
Peridinium
Pinnularia
Spirogyra
Ceratium
Ulothrix
Anabaena
Anacystis
Navicula
Oscillatoria
Volvox
Cladophora
Chlamydomonas
Tabellaria
Nitzschia
Euglena
Algal Genus Pollution Index (Palmer 1969)
Genus
Anacystis
Ankistrodesmus
Chlamydomonas
Chlorella
Closterium
Cyclotella
Index
1
2
4
3
1
1
Genus
Micractinium
Navicula
Nitzschia
Oscillatoria
Pandorina
Phacus
Index
1
3
3
5
1
2
Euglena
Gomphonema
Lepocinclis
Melosira
5
1
1
1
Phormidium
Scenedesmus
Stigeoclonium
Syndra
1
4
2
2
Characteristics Determining Water Quality
Characteristic
Heavily
Polluted
Moderately
Polluted
Slightly
Polluted
Clean Water
Water
Condition
Brown,
possibly with
scum and froth
Brownish,
possibly with
scum or film
May be nearly
clear or slightly
muddied
Fairly Clear
Protozoans
Euglena,
Amoeba
Amoeba
Paramecium,
Euglena
Stentor,
Paramecium,
Euglena
Few Euglena,
but not many
ciliates
Algae and
Cyanobacteria
Oscillatoria
and possibly
Melosira
Oscillatoria
and Spirogyra
Pandorina
Oedogonium
and Navicula
Diversity Index
0-2
1-3
2-5
4-10
Source: Moody et al. 1985
Solutions?
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Biomanipulation: Zooplankton
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Prevention + Monitoring!
Cladocera Bosmina
Source: http://www.uv.es/~ciros/zoopl_en.html#CLADOCERA
Cladocera Daphnia
Source: http://www.wellesley.edu/Biology/Faculty/Mmoore/research_zooplankton.html
Copepods
Source: www.sahfos.ac.uk/Edu_plankton_bio_indicators_...
Zooplankton: Indicative of Water Quality
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At 20% grazing rate, zooplankton reduce
phytoplankton populations by 75%
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“Rapid decline in the phytoplankton population was
accompanied by a resurgence of rotifers and of
Cladocera, followed by another small resurgence of
copepods in October.”
Source: Geismar 2001
Biomanipulation: Daphnia
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filter feeder, but Oscillatoria clogs its
filtering apparatus
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Urban light pollution affects vertical
migration of Daphnia
Prevention
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Zakova:
–
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Limestone berm:
Long-term monitoring of the phosphorus,
chlorophyll a levels of the lake
Patrick Willoughby: “To my recollection there
has been no follow up regarding the
recommendations in the report you are
referring to…These may be able to be added
but I would need associated cost information
before a decision is made.”
Case Study: King County Major Lakes
Monitoring Program
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Water Quality Monitoring on Lake Washington
Algal Blooms/Phytoplankton
Zooplankton
Phosphorus Concentrations
http://dnr.metrokc.gov/wlr/Waterres/lakes/biol
ake.htm
My Stella model

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