Transcript Off-Site Impacts Affecting Water

Off-Site Impacts Affecting Water
Fall 2012 , Lecture 8
Areas Affected
• Many factors influence water quality in rivers, lakes, estuaries,
seas, and oceans
• An estuary is a place where fresh water from a river mixes with
ocean water
 The water is brackish, meaning it has a salinity between that of fresh water
(very low salinity) and the open ocean (about 35,000 parts per million salt)
• A sea is a large body of saline water that may be connected with
an ocean, like the Mediterranean Sea, or may be a large saline
lake that, like the Caspian Sea, lacks a natural outlet
2
Previously Encountered Factors
• Some of these factors we have encountered
previously
 Agricultural runoff
• Sediment due to erosion
• Fertilizers
• Pesticides
 Deforestation, often leading to sediment erosion
3
Storm Water Runoff
 Storm water runoff, particularly from urban to suburban
regions
• May include fertilizers applied to lawns and gardens, and pet and
wildlife waste
• Also include pollutants like motor oil, gasoline, antifreeze, power
steering fluids, and tire residue from roads
• Household hazardous wastes like insecticides, pesticides, paint,
solvents, used motor oil, and other auto fluids
• Can also include debris carried into drainage networks and streams
 Examples: plastic bags, six-pack rings, bottles, and cigarette butts washed into waterbodies can choke, suffocate, or disable aquatic life
like ducks, fish, turtles, and birds
4
Effect of Stormwater Runoff
• Polluted stormwater often affects drinking water
sources
• This, in turn, can affect human health and increase
drinking water treatment costs
• Bacteria and other pathogens can wash into
swimming areas and create health hazards, often
making beach closures necessary
5
What is Pollution?
• A very useful definition of pollution is , “something
in the wrong place at the wrong time in the wrong
quantity” (from Holdgate, M.W. 1979. A Perspective of Environmental
Pollution. New York: Cambridge University Press. 278 pp.)
• The word pollution is derived from the Latin term
polluere, which means to soil or defile
6
Non-Point Source Pollution
• Most of the discussion of pollution in this
lecture involves non-point source pollution, a
very difficult source of pollution to clean up
7
Effect of Pollution in Water
• One of the most important effects of pollution in
waterbodies is called eutrophication
• Eutrophication is a word which comes from Greek:
eutrophia—healthy, adequate nutrition, development
• Although this is the word origin, it is really applied
incorrectly - a more correct term would be
hypertrophication – excessive nutrients
8
Eutrophication definition
• The addition of artificial or natural substances,
such as nitrates and phosphates, through
fertilizers or sewage, to an aquatic system
• It is sometimes called nutrient pollution, and
involves Holdgate’s “wrong quantity”
definition of pollution
9
Eutrophication Caused Problems
• Nitrogen and phosphorus are nutrients that plants need to grow
• Problems occur when an excess amount of these nutrients are
delivered to a water body, which causes an excessive growth
of algae, clouding the water
• This leads to more serious problems
 Hypoxia - low levels of dissolved oxygen as the algae decomposes,
defined as dissolved oxygen ≤ 2.0 mg l-1
 Anoxia – Near zero oxygen levels, defined as dissolved oxygen <0.2
mg l-1
10
Dissolved Oxygen (DO)
• Dissolved oxygen is critical to the survival of
aquatic life
• The amount of dissolved oxygen needed
before aquatic organisms are stressed, or even
die, varies from species to species
11
Nutrient Sources
• Nutrients are carried from the land by rivers as
a result of weathering of rocks and soil in the
watershed
• These nutrients enter estuaries and the ocean
• In estuaries, they can also come from the
ocean due to mixing of water currents
12
Anthropogenic Nutrients: Coastal Zone
• Anthropogenic nutrients are mainly related to people living on
and in the coastal zone because human-related impacts are
much greater than natural inputs
• More people living in the coastal zone means more nutrients
entering our coastal waters




From wastewater treatment facilities
Runoff from land in urban areas during rains
From farming in the coastal zone
Pet and wildlife waste also contributes
13
Anthropogenic Nutrients: Upstream Sources
• Upstream sources impact water bodies as well
• It’s important to focus on the coastal zone, and
on upstream sources of nutrients
• Eutrophication can happen in lakes, streams,
estuaries, or in portions of the ocean
14
Estuarine Research
• Most research is done in estuaries or bays
• Estuaries are of particular interest because of their use for
recreational and commercial fishing
• These are supported because estuaries are typically full of fish
populations, being among the most biodiverse regions on earth
• Since eutrophication can cause low dissolved oxygen which
kills fish, fisheries are in danger from nutrient pollution
15
Sandlake
Estuary Video
• Sandlake Estuary, Tillamook County, Oregon
showing the large biodiversity typical of estuaries
16
Initial Eutrophication
• Green masses of algae growing on a pond, a lake, or in an
embayment, are the first signs of eutrophication
• The layer of algae blocks light that is needed for seagrasses to
grow
• Seagrasses are plants that grow in shallow waters
• They live rooted at the bottom of the pond or in shallow
coastal areas and in extreme cases the lack of light will kill
them
17
Eutrophication Graphic
18
Algae on Ponds
19
• Photo caption: “Duckweed
and filamentous algae are
predominant in this photo. Too
much of both for any pond
which can cause fatally low
dissolved oxygen levels
causing fish loss.”
• Duckweed is a tiny plant with
little leaflets and roots,
which can literally cover an
entire pond.
• It is commonly transferred
from pond to pond by
waterfowl
Duckweed
20
Dr. Suzanne Bricker
• She is a physical Scientist and Manager
of NOAA's National Estuarine
Eutrophication Assessment, National
Centers for Coastal Ocean Science
• She was the lead scientist in the U.S.
National Estuarine Eutrophication
Assessment study (NEEA), which
provided a integrated framework for
eutrophication assessment and carried
out a comprehensive overview of 141
estuaries in the United States
• Slides 22-35 are based on the NEEA
assessments, and there are links on the
additional information page to this work
21
Eutrophication Locations
• Eutrophication is not limited to ponds or lakes
– it can also occur is estuaries, more open
coastal waters, and even in the deep ocean
• In coastal areas, algae blooms can appear red
or brown in color.
22
Stinky Beach
• In some areas, floating algae will wash up on a beach
and really smell as it decays making the beach an
undesirable place to go.
• Some estuaries have a place called “stinky beach,”
that is very characteristic thing with those decaying
algal mats
• These things may make the water body look murky
and smell unhealthy
23
Economic Harm
• Toxic algal blooms can decrease fishing
success and can cause losses of tourism
• They can also decrease real estate values
24
NEEA Estuary Reports
• Starting in the early 1990’s, NOAA’s National Estuarine Eutrophication
Assessment division conducted a national study of eutrophication
• They looked at 141 estuaries, measuring nutrient levels in the estuaries, and
trying to determine the source of the nutrients
• NEEA reported more than half of those estuaries had significant nutrientrelated problems
• The report also suggested that conditions in most estuaries were at risk of
becoming worse in the future due to expected increases in population in
coastal areas
• An updated report was issued in 2007, that looked at conditions in the early
2000s and how things had changed since the early 1990s
25
Data Agglomeration
• NEEA relied on local experts who monitor the 141
estuaries to provide data
• These investigators take measurements of algae,
dissolved oxygen, and seagrasses, as well as other
things, several times a year in their particular, or
specific, estuary
• By looking at the changes that occur over time, those
scientists can examine how the estuary is doing and
whether things are changing in an undesirable way
26
2007 Report Conclusions
• Overall, the U.S. is holding the line against further
eutrophication problems
• There were improvements in some estuaries, which is
good news, but in about an equal number of estuaries
conditions have worsened since the early 1990s.
• However, there are regional trends which differ from
the national trend
27
Least Impacted Estuaries
• The U.S. was divided into five regions - the North Atlantic,
Mid-Atlantic, South Atlantic, Gulf of Mexico, and the Pacific
Coast
• The least impacted estuaries, nationally speaking, occurred or
are located in the North Atlantic region, which includes the
coastline from Cape Cod to Maine
• These systems are different from most other regions:
 They have fewer people living in the watershed
 The tidal range is very high, so there is very good mixing with the
ocean for most of the systems that occur there
28
Most Impacted Estuaries
• The most impacted systems we found were in the
Middle Atlantic, from Cape Cod down to Chesapeake
Bay
• The Middle Atlantic region has probably the highest
density of people living in the region
• Many of the estuaries in the Middle Atlantic have a
smaller tidal range and poor mixing with the ocean
29
Source of Problems
• Human activities that impacted the systems
include:
 Agriculture including both the use of fertilizers
and animal operations
 Wastewater treatment plant effluent
 Urban/suburban runoff
30
Global Eutrophication
• NEEA also found that eutrophication is not just a
problem in the United States
• It impacts estuaries on a global level – consequences:
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Loss of seagrasses
Loss of fish habitat
Low levels of dissolved oxygen
Longer-lasting or first-time blooms of nuisance or toxic
algal
31
Global Cooperation
• Chinese and European scientists have worked with NEEA, and
NEEA learned that there are serious problems with
eutrophication in estuaries and coastal water bodies in both
places
• By sharing NEEA methods and learning from scientists in
other places about management measures that have been
successful in reducing eutrophication, NEEA is trying to
improve management techniques
• Eutrophication is a global problem and everyone can benefit
from working together
32
Shellfish
• One way to reduce algal growth within a water body
is to have large populations of oysters or clams
• In Chesapeake Bay, there used to be very large,
thriving populations of oysters which filtered the
water body and kept the Chesapeake Bay waters
clearer
• When those oysters died, Chesapeake Bay started
having problems, in addition to the fact that there
were more nutrients entering the system
33
Shellfish Farming
• Shellfish farming or encouraging natural
populations can be used for natural water
filtration even though the nutrient load is not
actually reduced
34
Seasonal Variation in Estuaries
• Many estuaries receive varying amounts of
freshwater inputs seasonally
 This can be due to terrestrial wet/dry seasons
 It can also be due to high inputs of snowmelt
waters in spring, especially after a winter with
heavy snowfall
35
Snowmaggedon
• The February 5–6, 2010 North American blizzard, also known
as "Snowmaggedon", was a Category 3 ("Major") nor'easter
and severe weather event
• Most crippling was the widespread 20 to 35 in (50 to 90 cm)
of snow dropped across southern Pennsylvania, the Eastern
Panhandle of West Virginia, northern Virginia, Washington,
D.C., Maryland, Delaware, and southern New Jersey
36
Snowmaggedon Photos
In Pittsburgh, over 20 inches (51 cm) of snow
fell causing numerous power lines and tree
branches to buckle.
19th Street in Dupont Circle, Washington D.C.,
Northwest, where ~24" of snow had fallen on
February 6th by day's end.
37
Eastern
U.S.
Satellite
Image
• North American blizzard of 2010, imaged by NASA's Aqua satellite on
February 5, 2010
38
Four Nor’easters
• Snowmaggedon was the second of four nor'easters during the
2009-2010 winter that brought heavy snow to enough of the
Northeast's population to be numerically recognized by
NOAA's NESIS intensity rating
• The first and third of these systems, the December 2009
Nor'easter and the February 9–10, 2010 North American
blizzard, respectively, combined with this event to bring the
snowiest winter on record to much of the Mid-Atlantic
39
Three Nor’easters in 12 Days
• Snowmaggedon was the second of three major Mid-Atlantic
snowstorms that occurred over a 12-day period
• Each subsequent storm focused its heaviest snow slightly
farther north: the January 30, 2010 storm (not recognized by
NESIS) dropped more than a foot of snow across Virginia and
the lower Chesapeake Bay region, while the February 9–10,
2010 North American blizzard bulls-eyed the MarylandPennsylvania border with as much as 28 inches
40
Chesapeake Bay, 2009-2010
• In 2010, river flow to the Chesapeake Bay was above average
in winter (November and December 2009, January 2010) and
March, and lower than average in late spring (April, May) and
summer (June-September)
• Above average flow in winter coincides with the significant
amount of snow that the Chesapeake watershed received
during December 2009 and January-February 2010
41
Increased River flow effect
• As river flow
increases the
amount of
nutrients
entering the
Chesapeake
Bay
42
March 2010 Bloom
• The nutrients
fuel
phytoplankton
growth and
subsequent
algae blooms
43
Production of Hypoxia
• Phytoplankton eventually die and sink to deeper water where
bacteria consume the dead phytoplankton in a process that
consumes oxygen, leading to potentially hypoxic or anoxic
conditions
• An increase in fresh water entering Chesapeake Bay from its
surrounding rivers also reduces the amount of oxygen that can
be mixed into deeper waters
• The water from the rivers tends to flow on top of the salty
water because fresh water is lighter than brackish water
44
Density Stratification
• This “layering” of water is an example of stratification, due to
density
• It prevents mixing between the fresher water on top and the
saltier water on the bottom
• The only source of oxygen for deeper waters is from the
surface water (where phytoplankton grow and produce oxygen
and where oxygen from the atmosphere mixes into the water)
45
Reduced Mixing
• Stratification of the water reduces mixing of
oxygen into deeper waters
• This makes it more likely for anoxia and
hypoxia to develop in the deeper waters
46
Early Hypoxia/Anoxia Maximum
• The flow into Chesapeake Bay in 2010 appears to have
affected summer conditions by shifting the intensity of low
dissolved oxygen conditions to earlier in the summer
• Higher flow in winter and March led to an early maximum of
anoxia and hypoxia in late June because an especially large
and dense phytoplankton bloom developed in March in the
mid to upper Bay
47
Thermal Stratification
• Water above 4̊ C is less dense than colder water, due to thermal
expansion
• The high early spring flow combined with hot temperatures in
early summer led to strong stratification in June
• The impact of the high winter and March flow would likely be
complete by the end of June because the effects of strong
March river flow only last for 90-120 days
48
Low River Flow
• Extremely low river flow
from April to July led to less
nutrients entering the Bay
(which slowed the growth of
phytoplankton) and reduced
stratification later in the
summer, allowing the
bottom waters to be mixed
with oxygen-rich surface
water
49
June Maximum
• The winds in August blew from the southeast most
frequently, a direction of wind that favors the mixing
of oxygen from surface water and the atmosphere into
deeper waters to relieve low dissolved oxygen
conditions
• As a result of all these processes, hypoxia was
reduced and the anoxia disappeared in late summer
50
2010 June Maximum
• In 2010, the largest volume of
anoxia and hypoxic waters occurred
in late June
• This map shows the late June
bottom minimum DO for
Chesapeake Bay
• A very large amount of anoxia
occurred in late June, the second
highest amount on record
51
Late Summer Reduction
• After March, the flow and nutrients
slowed down, with below average
amounts from April through August
• Anoxia cannot be sustained at high
levels throughout the summer
without new nutrients coming into
the Bay
• By the end of August, the volume of
anoxia was smaller, and by late
September, anoxia was completely
gone
52
Change in Pattern
• Thus, the Snowmaggedon and other severe
Nor’easter events of 2010 drastically changed
the usual pattern of anoxia and hypoxia in
Chesapeake Bay
• This has a profound effect on the ecological
cycles
53
Climate Change?
• Were the Nor’easter events related to climate change?
• Present day climate science cannot say with certainty
if a particular event is due to climate change
• Statistical analyses reveals far more frequent
“maximum” events
• Many scientists feel the large deviation of the
maximum events from the norm are a very likely
indicator of the influence of climate change
54
Chesapeake Bay Video
• NASA video about satellite monitoring of Chesapeake Bay
55
Tampa Bay, Florida
• Between 1950 and 1980, half of the acres of seagrass
beds in Tampa Bay were lost as a result of the
murkiness of the water due to algae blooms
• Starting in the 1980s, local officials worked on
various actions to reduce nutrients that would then
reduce those algal blooms
56
Treatment of Tampa Bay Problems
• Wastewater treatment plants were required to
provide advanced treatment.
• Stormwater discharges were regulated
• The phosphate industry changed their practices
to reduce fertilizer spills at port facilities from
which fertilizer products were shipped
57
Tampa Bay Success
• The combination of these actions reduced
nutrient loads resulting in less algal growth
and the waters cleared up
• Seagrasses started growing again
 By 2004, researchers observed the highest level of
seagrass acreage since 1950
58
HAB
• HAB stands for Harmful Algal Bloom
• A number of different organisms can cause HAB’s – examples:
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Red Tide - Karenia brevis
Brown Tide - Aureoumbra lagunensis
Takayama tuberculata
Peridinium quinquecorne
Noctiluca scintillans
Prymnesium parvum
59
Red Tide
• Off the west coast of
Florida, Karenia brevis,
a marine dinoflagellate
common in Gulf of
Mexico waters, is the
organism responsible
for Florida red tide, as
well as red tide in Texas
60
Brevetoxins
• K. brevis is a microscopic, single-celled, photosynthetic
organism that can bloom frequently along Florida coastal
waters
• Cells have two flagella that allow them to move through the
water in a spinning motion.
• K. brevis naturally produces a suite of potent neurotoxins
collectively called brevetoxins, which cause gastrointestinal
and neurological problems in other organisms and are
responsible for large die-offs of marine organisms and seabirds
61
Safety
• Oysters clams, mussels, whelks and scallops can
accumulate red tide toxins in their tissues
• People that eat oysters or other shellfish containing
red tide toxins may become seriously ill with
neurotoxic shellfish poisoning (NSP)
• Once a red tide appears to be over, toxins can remain
in the oysters for weeks to months
62
Red Tide
Timeline
• The diagram illustrates known
occurrences of Red Tide in
Florida going back to 1844
• In recent years, Red Tide has
been a nearly annual
occurrence, particularly for the
period October through March
63
Current Red Tide Status
• The Florida Fish and Wildlife Conservation
Commission maintains a website at
http://myfwc.com/research/redtide/events/statu
s/statewide/ which lists current Red Tide
outbreaks
64
Red Tide Photo
• The photo shows Red Tide
associated with outflow from
the Caloosahatchee River flowing
into the Gulf of Mexico on
October 12, 2012
• Rick Bartleson, research scientist
for the Sanibel-Captiva
Conservation Foundation, said the
bloom started about a month ago
off Sarasota and has been slowly
moving south toward Lee County
65
Cause of Current Red Tide
• There are two reasons for the current outbreak:
 Runoff from the Caloosahatchee River due to recent heavy
rains
 Water releases into the Caloosahatchee River by the Army
Corps of Engineers from Lake Okeechobee, in response to
the rapid increase in lake level following Tropical Storm
Isaac (fro 12 to nearly 16’ a.s.l.)
• The increase in discharge rate carries increased
nutrients levels
66
Google Earth link
• The following link is to
a Google Earth map of
K. brevis
• GE-10-12-12.kmz
• The photo is a static
image of the web site
image
67
Brown Tides
• Aureoumbra lagunensis causes Brown tides, which
occur naturally and can be common in waters with
high salinity
• The brown tide algae have been noted from Florida to
Maine on the east coast and throughout coastal areas
of the Gulf of Mexico, but July, 2012 is the first time
FWC has documented a bloom of the algae in state
waters, in the Indian River Lagoon
68
Brown Tide Consequences
• Brown tide organisms are nontoxic and there are no known
human health concerns
• Shellfish and fish kills can occur during blooms due to brown
tides production of mucus that can prevent shellfish from
feeding
• A sustained bloom could impact shellfish populations in the
northern Indian River Lagoon
• Fish kills can occur when the algae deplete oxygen from the
water
69
Takayama tuberculata
• On July 5, 2011, Takayama tuberculata blooms were observed
at Vanderbilt Beach and Naples Pier
• Takayama tuberculata blooms have been documented along
Collier County annually since 2008
• High concentrations of T. tuberculata can deplete dissolved
oxygen and discolor the water red to brown
• Whether T. tuberculata blooms in Florida produce toxins is
undetermined
70
Takayama tuberculata Fish Kills
• On July 18, 2011 fish kills associated with low dissolved
oxygen concentrations were reported at Clam Pass and
Vanderbilt Beach
• Many aquatic species washed up, dead or dying, onto the
county's beaches
• Beachgoers were warned by to exercise caution due to the
"large number of stressed and dying animals in the surf zone
that could cause injury if stepped on."
71
Nurse Sharks in Shallow Water
• Local residents and
county officials were
surprised to see the
variety of creatures that
normally do not appear
in the shallows, such as
lobsters and nurse
sharks
72
Peridinium quinquecorne
• Peridinium quinquecorne can be found year-round in many
brackish and estuarine waters in Florida because it can tolerate
temperatures from 16 to 38ºC (60-100ºF) and survive in a wide
range of salinities (11 to more than 32 parts per thousand)
• When Peridinium quinquecorne occurs in blooms, it can cause
discoloration, from red to brown
• Although the organism is not toxic, it can cause fish kills as
the result of anoxia
73
Peridinium quinquecorne Blooms
• Blooms of Peridinium quinquecorne have occurred
alongshore of southwest Florida from late summer to
early fall since 2005
• In June 2010, water samples collected southern Lee
and northern Collier counties indicated a bloom of P.
quinquecorne extending from southern Sanibel Island
down to Seagate
74
Noctiluca scintillans
• Noctiluca scintillans bloom
offshore of Walton county on
Feb. 19, 2011
• It is a large, bloom-forming
dinoflagellate and is nontoxic
• No fish kills or other adverse
effects were reported in
February or March as a result of
the bloom in northwest Florida.
75
Noctiluca scintillans Fish Kills
• Blooms have been linked to
massive fish and marine
invertebrate kills from the
toxic levels of ammonia that
accumulate in surrounding
waters
• A pocket of air inside the
cell wall allows this algal
species to float
76
Prymnesium parvum
• Prymnesium parvum, also known as golden
algae, is a naturally occurring microscopic
member of the phytoplankton community
• It has been found in brackish waters
worldwide and has been noted in Florida
waters since 2005
77
Prymnesium parvum Toxicity
• It is a known toxin producer and has caused large-scale fish
kills in other parts of the United States and the world
• It can cause ecological and economic harm particularly to
aquaculture industries
• In Florida, fish kills caused by P. parvum have been localized
to small ponds in residential areas and golf courses and the
Intracoastal Waterway
78
Types of Toxins
• P. parvum can produce allelopathic compounds,
chemicals that inhibit growth in another species of
plant, that give the cells a competitive advantage over
other phytoplankton and grazers
• P. parvum also produces an ichthyotoxin, or fish
toxin, called prymnesin, which affects gill-breathing
organisms by rupturing gill membranes
79
Florida West Coast, Fall 2001
• In fall 2001, the SeaWiFS images showed an
extensive red tide off Florida's central west
coast, near Charlotte Harbor
• The waters containing this red tide migrated to
the south along the coast
80
Nutrient Transport
• Winter storms caused large amounts of fresh water to
drain from the Everglades into Florida Bight (the
curve in the shoreline from the Keys north to
Everglades National Park on the mainland), carrying
high levels of nutrients such as silicate, phosphorus,
and nitrogen to the sea
• These caused a bloom of the microscopic marine
plants known as diatoms in the same patch
81
• The diatom bloom turned the
water dark and the "black
water" patch re-circulated for
several months in a slow
clockwise motion off southwest
Florida in the Florida Bight
• Slowly, the dark water drifted
farther south and toward the
Florida Keys
Photo Caption: NASA's Terra satellite
acquired this image of a red tide
bloom along Florida's west coast
December 22, 2001
Diatom Bloom
82
Florida Bay, Early 2002
• A patch of "black water" spanning over 60 miles in diameter
formed off SW Florida and contributed to severe coral reef
stress and death in the Florida Keys, according to results
published from research funded by NASA, the U.S.
Environmental Protection Agency and the National Oceanic
and Atmospheric Administration (NOAA)
• The "black water" contained a high abundance of toxic and
non-toxic microscopic plants
83
Florida Bay
• True color
(brightness
enhanced 20%)
MODIS/Terra
image from
February 17, 2002,
shows black water
in Florida Bay
84
Florida Bay Video Animation
• SeaWiFS Image of
Blackwater
• True color date Jan. 9,
2002
85
Florida Bay False-Color Video Animation
• SeaWiFS Image of
Blackwater, date Jan. 9,
2002
• False color visualization
showing chlorophyll
• Reds and oranges represent
high concentrations of
chlorophyll
86
On-Site Studies in Florida Bay
• Chuanmin Hu and colleagues at USF Institute for Marine
Remote Sensing examined data collected by divers from the
dark water area in the Florida Keys
• They discovered a 70 percent decrease in stony coral cover, a
40 percent reduction of coral species, and a near-elimination of
sponge colonies at two reef sites after the dark water passed
87
Florida Bay Dead Zone
• They concluded that the coral reef ecosystem had
been stressed by a red tide of algal blooms and toxins
contained in the dark water
• Recent evidence also points to these phytoplankton
blooms being fed by increased nutrient input from
agricultural and urban run-off
• This is an example of what oceanographers call a
“dead zone”
88