Transcript No Slide Title - The Ocean Inquiry Project

“Life in Puget Sound, or
What you (almost) can’t see…”
Puget Sound -- a
fjord, an estuary, an
ecosystem
Earth data from SEAWifs; Puget Sound data from PRISM project
Somewhere here is the
secret to life in Puget
Sound...
and here...
and here...
and here...
South tip of Camano Island, September 2, 2002
Why is Puget Sound such a great place
for marine life? Primary Productivity!
• Primary productivity is a
bio-chemical process
(mostly photosynthesis) that
converts the sun’s energy
into food for the entire
ecosystem.
• Primary producers need
nutrients, water, carbondioxide, and energy (light)
to create the organic carbon
all other life depends on.
Primary production measurement
Ocean productivity is
measured in grams of
carbon produced per
square meter per year.
A typical ocean rate is
~ 120 gC/m2/yr, but in
the main basin of
Puget Sound the rate
is ~ 460 gC/m2/yr.
Why is Puget Sound so productive?
(let’s look at nutrient cycling in the open ocean)
Hint: find the four things phytoplankton need in this diagram.
Land and ocean productivity by season
September - November
March - May
December - February
June - September
Global Distribution of
Plankton Productivity
The distribution of phytoplankton corresponds to the distribution of
macronutrients. The productivity of plankton varies between the
seasons.
© 2002 Brooks/Cole, a division of Thomson Learning, Inc.
Washington coast productivity over time
Productivity is typically nutrient limited;
how do we get nutrients to the surface?
The coast has
upwelling...
…and the Sound
has mixing!
Computer
models
can
help us to
predict
circulation
(and thus
upwelling)
in Puget
Sound . . .
Model provided
by Mitsuhiro
Kawase, UW
Oceanography
. . .this movie
shows
surface
temperature
in Puget
Sound
over 1 tidal
cycle.
Plankton serves as the base of the food chain
(and as the source of oceanic organic carbon) .
..
…but feeding efficiency is only about 10% per trophic level.
In a food web,
phytoplankton and
cyanobacteria are
at the lowest level,
zooplankton at the
next, and so on.
Detritus (and
bacteria that break
it down) reconnect
all levels to the
primary producers.
© 2002 Brooks/Cole, a division of Thomson Learning, Inc.
A local food web - Padilla Bay, WA
Plankton and how to catch it
Plankton are drifting plants, bacteria, and animals of many different
species and sizes. We collect plankton with nets and study it in
many ways, from simple observation under a microscope to genetic
analysis with sophisticated DNA techniques.
© 2002 Brooks/Cole, a division of Thomson Learning, Inc.