Biology 370 – Environmental Science
Name:
.
Environmental Science Lab #2
“A Field Study of Ecosystems”
(20 points)
INTRODUCTION
In 1935, Sir Arthur Tansley coined the word “ecosystem” from the
two words “ecological” and “system”. By combining these two words he
acknowledged for the first time the interconnected nature of the surrounding
ecological world. In today’s lab you will learn about an ecosystem by
interacting with it and understanding its unique tapestry. Today’s lab
objectives are:
A.
Understand and be able to identify in the field the two (2)
broad components of an ecosystem.
B.
Understand how components interact via the “lines of
dependency”, that makes up ecosystem “structure” and
“function”.
C.
Understand and explain how humans exist and affect
ecosystem structure and function.
ECOSYSTEM BACKGROUND
In today’s lab, we will visit the MacDonald-Dunn Experimental
Forest located near Corvallis, Oregon. Adjacent to the forest is OSU’s
Peavy Arboretum. We will access the forest through the arboretum and
drive through a gate to an area near Cronemiller Lake. Once at the lake,
your task is to work in groups of two or three students to hike and observe
the lake trail and answer a series of 10 questions regarding the surrounding
ecosystem. The questions are designed to help you understand how
ecosystems are structured (i.e. the strands of the tapestry) and how they
function (the picture of the tapestry once the strands are woven together). I
will be hiking with you and will help you with clues to the answers. Please
don’t hesitate to ask and work together. As we progress through the term we
will investigate several themes in the labs:
A.
B.
C.
D.
E.
How are ecosystems structured?
How do ecosystems function?
What are ecosystem “services”?
What role(s) do plants and animals play in the structure and
function of an ecosystem?
How do humans affect the structure and function of
ecosystems as they derive ecosystem “services”?
Biology 370 – Environmental Science
The Mac-Dunn Forest is an Ecosystem (definition):
Simply stated, ecosystems are the sum of all
living and non-living organisms in an area that, as
structured, function as a whole unit. In the picture
below, locate the biome (ecosystem) that Mac-Dunn
Forest fits in terms of precipitation and temperature.
Questions
1.
What are the two primary components of
an ecosystem? In which biome does the
Mac-Dunn Forest fit?
2.
Locate the water source for
Cronemiller Lake (if you can)?
3.
As you hike around the Lake, be observant and note the types
and amount of vegetation. How many species of plants do you
suppose are found in the immediate vicinity of the lake? How
many species are found in the lake?
Biology 370 – Environmental Science
4.
Note the number and types of animals around the lake. How
many did you see? Remember, the time of the year – the number
of species found here increases during late spring and summer.
Speculate why such a difference between the seasons?
5.
How does water move through this system? In other words,
trace the path of water from the lake to plants and animals. How
does water leave plants and animals? Where does it travel next?
6.
Besides water, what other types of substances are important for
plants and animals in this system? How do they (plants and
animals) derive those substances?
Biology 370 – Environmental Science
7.
Explain in some ways how animals (land and water) interact with
each other in this system.
8.
Explain in some ways how plants (land and water) interact with
each other in this system.
9.
Finally, explain how plants and animals interact with each other
in this system.
10.
How would/could you define the boundary of this ecosystem?
Biology 370 – Environmental Science
When you have finished your hike, return to the van, so that we can
compare answers and discuss them.