ALIENS? INVADERS?... ALGAE!
These past few months area lakes have seen some incredible almost “other-worldly,” sights. We guarantee that the puzzling green spheres
under the surface of the water are not signs of extraterrestrials. It’s algae,
as much a part of the ecosystem as you, me and the trees.
The Discovery Center has received various samples of the
algae and upon sending them to a DNR laboratory for identification, has learned
what the E.T.-esque blooms contain. (Can you believe that one local lake alone
had thirty species of algae in it?!) A portion of the samples were identified
as “green algae,” a group that is not harmful to species higher up in the
trophic system (e.g. birds, dogs, humans).
Some of the samples also contained “blue-green algae.”
Infamous due to the Toledo, Michigan incident last summer, it is well known
that blue-green algae can emit toxins harmful to mammals. It is strongly believed,
however, that this particular species is native to the area and therefore has a
role in our lake ecosystem.
EARLIEST PIONEERS
To be more precise, algae was part of Earth’s ecosystem
before you, me and the trees ever existed. The birth of our planet was not
overly hospitable to any species. It can be surmised, then, that this
particular form of algae had to be hardy and adaptable in order to survive.
It is due to that same adaptability that Earth has one of
its most defining characteristics- an atmosphere.
Being a mess of molten rocks and toxic fumes, the newly
created Earth was at its most impressionable stage. One minor change in the
chemical exchange of respiration allowed algae to take a mound of clay and
create a masterpiece; everything that we have today- water, immense
biodiversity, numerous ecosystems and the laws of nature- can be linked back to
an act of adaptation at an opportune time. Quite a coincidence, right?
IMPORTANCE OF EXISTENCE…
Algae is ingrained into lake ecosystems. It can be difficult
to picture these simple, single-celled organisms being as significant to the
balance of nature as the much larger fish and birds, but they are. Fact is, most
algae species are the basis of energy in the food web.
All living species rely on energy to undergo basic
biological processes. We need it to breathe, to digest, to think, and to move.
Algae are essentially tiny power plants that undergo photosynthesis to create
their own energy. Then, when consumed, the predator attains a portion of that
energy and so on and so forth as it goes up the food chain to those large
fishes, aquatic birds and nearby mammals. If algae were not present, the food
web would be crippled at the base.
Another important function of algae in water is their
assistance of pollutant regulation. Chemicals and heavy metals, vastly
detrimental to the health of every living thing in the lake, can be
bioaccumulated (accumulation through biological means and processes) in algae.
By consolidating these toxic compounds in one location, there is less risk of
harm towards other species. Thanks, algae!
…IN MODERATION
All healthy lake systems contain algae. This, like every
other aspect of water systems, needs to be in moderation. Too much algae or too
little algae can create far-reaching and long-lasting problems. As previously
mentioned, small algae populations can restrict the flow of energy through
predator-prey interactions.
Algal blooms, an example of excessive algae, undermine order
and balance in the water. A bloom can cause havoc by killing plants, reducing
oxygen levels and either killing or driving away aquatic species. Such events
are common in lakes populated by humans or near anthropogenic activity. How
does that work?
It has to do with the nutrients being loaded into water
systems. More specifically, additions of nitrogen and phosphorus into the water
body will increase the potential for massive increases in algae production.
Combined with abundant sunlight and slow moving water (i.e. lakes), the
likelihood of an algal bloom is higher.
ACTION FOR PREVENTION
So how do we stop the algae take over? Sometimes it will
inevitably happen, but we can reduce the severity and extent of its spread.
- First and foremost, we can reduce the amount of nutrients we are adding into the outside ecosystems. Via water runoff into lakes, any nitrogen or phosphorus additions to lawns, gardens, et cetera near water bodies will get into the lake.(Note: Examples of nutrient additions include fertilizers, animal feces, cleaning soap for motor vehicles, improperly maintained or failing septic tanks)
- Second, we can limit the amount of nutrients we use within the four walls of our homes. For example, phosphate-free soaps will reduce the amount of phosphorus that inevitably goes down the drain and into the surface water.
- Third, monitoring the lake for increased algae activity. By knowing what alga growth is normal and what is not, we can better work with our lakes to reduce nutrient input and maintain a happy balance.
