Name __________________________________
Freshwater Ecosystems – Chapter 7, Part I
Environmental Science
I.
Objectives:
a. Describe the factors that determine where an organisms lives in an aquatic ecosystem
b. Describe the littoral zone and the benthic zone that make up a lake or a pond
c. Describe two environmental functions of wetlands
d. Describe one threat against river ecosystems
II.
Freshwater Ecosystems
a. The types of organisms in an aquatic ecosystem are _____________________________
______________________. As a result, aquatic ecosystems are ___________________
_______________________________________________________________________
b. Freshwater ecosystems include
i. ________________________
ii. ________________________
iii. ________________________
iv. ________________________
v. ________________________
c. Wetlands are __________________________________________________________ or
________________________________________________________________________
III.
Characteristics of Aquatic Ecosystems
a. Factors that determine which organisms live in which are of the water include
i. ______________________________
ii. ______________________________
iii. ______________________________
iv. ______________________________
b. Aquatic ecosystems contain _________________________________________________
________________________________________________________________________
c. Three groups of organisms
i. Plankton – ________________________________________________________
_________________________________________________________________
1. Zooplankton –
_______________________________________________
2. Phytoplankton – _________________________________
3.
IV.
ii. Nekton – ___________________________________________________ in open
water, independent of currents
iii. Benthos – ______________________________________________ of the sea or
ocean and are _____________________________________________________
d. Decomposers are also _____________________________________________________
Lakes and Ponds
a. Lakes, ponds and wetlands can form __________________________________________
________________________________________________________________________
b. Humans intentionally create ________________________________________________
and streams to use them for ________________________________________________
c. Lakes and ponds can be structured into _______________________________________.
The types of organisms present ______________________________________________
d. Life in a Lake
i. The littoral zone is a ___________________________________________ where
light reaches the ___________________________________ and aquatic life is
_________________________________________________________________
ii. Some plants are ____________________________________________________
_________________________________________________________________.
iii. Other plants have __________________________________________________
iv. In open water, plants, algae and some bacteria __________________________
_________________________________________________________________
photosynthesis
v. Some bodies of fresh water have areas _________________________________
_________________________________________________________________
vi. Bacteria live in the _____________________________________________. Fish
adapted to _______________________________________________________.
vii. Eventually, ________________________________________________________
reach the benthic zone
viii. The benthic zone is the region ________________________________________
which is __________________________________________________________
_________________________________________________________________
ix. Animals that live in lakes and ponds have _______________________________
_________________________________________________________________
1. Examples – Water beetles use the hairs under their bodies to trap
__________________________________________________________
__________________________________________________________
2. In regions where lakes partially freeze in the winter, _______________
__________________________________________________________
__________________________________________________________
e. How Nutrients affect lakes
i. Eutrophication is an ________________________________________________,
such as nitrates, in an aquatic ecosystem
ii. As the amount of plants and algae grow, the ____________________________
_________________________________________________________________
iii. These bacteria use the ______________________________________________.
Eventually the _____________________________________________________
_________________________________________________________________
iv. A lake that has large amounts of plant growth ___________________________
_________________________________________________________________
v. Lakes naturally ____________________________________________________
vi. However, eutrophication can be accelerated by __________________________
_________________________________________________________________
into bodies of water
V.
Freshwater Wetlands
a. Wetlands perform several important environmental _____________________________
b. Wetlands act like _________________________________________________________
___________________________________________________________ from the water
c. They control flooding by ___________________________________________________
d. These areas provide a home for _____________________________________________
in addition to ____________________________________________________________
________________________________________________________________________
e. Environmental Functions of Wetlands
i. _____________________________________________, nutrients and
pollutants, which keep these materials from entering lakes, reservoirs and
oceans
ii. ______________________________________________________________,
roads, buildings and human health and safety
iii. ______________________________________________________________
iv. _____________________________________________________________ for
commercially important fish and shellfish
v. _________________________________________________________________
plants and animals
vi. _____________________________________________________ for activities
such as fishing, bird-watching, hiking, canoeing, photography, and painting
f. Marshes
i. Freshwater marshes tend to occur on __________________________________
_________________________________________________________________
ii. In shallow water, plants root _________________________________________
while their leaves ______________________________________________ of
the water year-round
iii. There are several kinds of marshes
1. _______________________________________
2. _______________________________________
3. _______________________________________
iv. Benthic zone – ___________________________________________, numerous
types of decomposers and scavengers
v. Water fowl (ducks) – adaptations such as _______________________________
_________________________________________________________________
vi. Water Birds (herons etc). – adaptations such as _________________________
________________________________________________________________
vii. Marshes also attract ________________________________________________
_________________________________________________________________
g. Swamps
i. Occur on _____________________________________, often near streams
ii. Dominated by __________________________________________________
iii. Are ideal habitat for _____________________________________________
iv. Birds are attracted to ____________________________________________
v. Reptiles are the ______________________________________, eating almost all
other animals
h. Human Impact on Wetlands
i. Wetlands were previously considered to be _____________________________
_________________________________________________________________
ii. As a result, _______________________________________________ for farms
or residential and commercial development
iii. The importance of wetlands is now recognized, as the law and federal
government ______________________________________________________
_________________________________________________ of certain wetlands
VI.
Rivers
a. At its headwaters, a river is ____________________________________________ and
_____________________________________________________________________
b. As a river flows down a mountain, it may ____________________________________
______________________________________________________________________
c. A river changes __________________________ and the ____________________
through which it flows
d. In and near the headwater, mosses _______________________________ to rocks by
using rootlike structures called _______________________________.
e. Trout and minnows are __________________________________________________
f. Farther downstream, ___________________________________________________
i. Plants here can set _______________________________________, and the
plants leaves vary in ___________________________________________ of the
rivers current
ii. Fish such as _______________________________________ also live in these
calmer waters
g. Rivers in Danger
i. Industries use _____________________________________________________
________________________________________________________for wastes
ii. People have used rivers to __________________________________________
iii. These practices have ___________________________________, which have
killed river ________________________________________________________
iv. Runoff from the land puts ______________________________________- into
rivers and ________________________________________________________