Marine Snow-Lesson plan
Summary
Marine snow is the falling of organic and inorganic materials from the light rich
photic zone to the deep sea. As the particles fall microorganisms and bacteria
consume them, they also aggregate together into larger clumps, bound by mucus
from plankton. Marine snow is the main source of food for deep-sea animals. It
also contributes to the formation of deep-sea sediments; microfossils in the
sediments, such foraminifera, can give geologists clues about past climatic
events. Upwelling currents in some ocean basins can transport the nutrients back
up to the surface waters were they are utilized by phytoplankton completing the
cycle of matter and the flow of energy in the open oceanic food chain. The
sediments are also important to the geologists on-board the JOIDES Resolution,
if there is a good depth of sediment then it is much easier to drill a hole into the
seabed than if there isn’t. This is because the drillers need to be able to stabilize
the drilling equipment before they begin to make a hole. This work package
looks at these processes, the students learning is consolidated by the completion
of a practical activity.
Learning objectives.
 To understand the importance of marine snow as a source of food for
deep-sea animals.
 An understanding of the important role the microfossils of foraminifers
playing in understanding past climatic events.
 An appreciation of the role that upwelling currents serve in the completion
of the open oceanic food chain.
 An awareness of the differences between organic and inorganic matter.
 Feeding relationships in an open ocean food chain.
National Science Standards.
A. Science as an inquiry.
D. Earth and Space Science.
Ocean Literacy Links
1. The earth is one big ocean with many features.
2. The ocean and life in the ocean shape the features of the Earth.
5. The ocean supports a great diversity of life and ecosystems.
7. The ocean is largely unexplored.
Target age: 13-14 years old
Lesson time: 1-class periods.
Preparation
The class should have an opportunity before the session to learn about the work
of the IODP.
Information about IODP
The Integrated Ocean Drilling Programm (IODP) is an international research
program that explores the history and structure of the earth as recorded in
seafloor sediments and rocks. It seeks to expand the reach of several previous
programmes by a collaborative union between the United States, Japan and the
European Union. The JOIDES Resolution is the research vessel that is operated
by the US. Scientists from all over the world participate in expeditions aimed at
investigating the principle science themes for IODP: the deep biosphere and the
sub-seafloor ocean, environmental change, processes and their effects and solid
earth cycles and geodynamics
Materials.
Downloadable teachers notes, oceanic map and stickers.
What to do.
1. Ask the students what they understand about the term ‘marine snow’ give
them 5 minutes to jot down as many ideas as they can think of. They may
work in small groups for this task.
2. Explain to the class the cyclic process of how marine snow accumulates
in the sediments and is transported back into oceanic food chains.
3. Distribute the worksheet and stickers and ask the students to place the
stickers in the correct place, they may also annotate their work and
provide additional information.
Resources
www.youtube.com/watch?v=EF4IAGAXZsM
http://oceanservice.noaa.gov/facts/marinesnow.html
http://www.whoi.edu/oceanus/viewArticle.do?id=2387&archives=true
Authors: Susan Gebbels, Nicole Kurtz and Jean-Luc Berenguer