Welcome to the International Conservation
Society's Freshwater Conservation Page.
Examples of freshwater ecosystems
include streams, rivers, lakes and wetlands. Each is complete with its own special blend of biodiversity. Each is also dependent
on and interacts with adjacent terrestrial ecosystems.
When runoff is not controlled, eutrophication
results. This is from an overabundance of nutrients causing disproportionate exponential growth in algae and other plant life.
This concentration of plant life chokes off fish and other aquatic animals.
With no animals to provide oxygen
the plant life can no longer sustain itself. As it decays the sediments settle to the bottom of the water, forming a rich
Below the humus, however, the denser
runoff soil settles first, filling in the body of water in question along with the decomposing organic material.
The decomposing plants, fish, etc
are highly rich in nutrients. This facilitates the growth of terrestrial plants as the river, lake, pond, or other body of
water fills in. the freshwater ecosystem thus ecologically succeeds to a bog or marsh. Should eutrophication continue this
system will further succeed into a forest. This process can also occur in wetlands, completely changing the type of wildlife
that can sustain itself there & destroying this unique source of biodiversity.
Eutrophication can be prevented
by the prevention of runoff. Some ways to accomplish this are the planting of trees and other plants to contain topsoil, the
erection of soil erosion barriers, and containment of agricultural soil.
Containing agricultural runoff is
particularly important because of the high concentrations of phosphorous in fertilizer. This phosphorous promotes plant growth
and thus drastically accelerates the eutrophication process.
Non-point source pollution is also
a killer of freshwater ecosystems. Chemicals released into the soil wash into the streams, lakes, rivers, wetlands and oceans,
contaminating and possibly eventually killing the plants and animals which inhabit them.
Click on the links below for
more information about freshwater ecosystems and how to preserve them.