nutrient levels – Aquarius-Systems

Aquatic Plants Play Key Role in Water Clarity Balance

Tue, 05 Dec 2023 22:23:44 +0000

Posted on July 9, 2013 by Dan O’Keefe, Michigan State University Extension

Aquatic ecologists tend to avoid the term “weeds” when referring to macrophytes – the rooted aquatic plants that many swimmers and boaters disdain. These plants provide food for waterfowl and habitat for fish, but they can also play a critical role in maintaining water clarity.

Many lakes and ponds have two stable states: weedy and clear or devoid of weeds and muddy. This leaves riparian landowners and lake managers with a choice between two undesirable endpoints when nutrient levels are intermediate.

At low nutrient levels, the rooted plants win out because water is clear and plenty of light reaches the bottom of the lake. At high nutrient levels, the algae win out and effectively shade out rooted plants – this means extremely low water clarity and sometimes harmful algal blooms. At intermediate nutrient levels, things get a bit tricky. In this case, lakes can be pushed in one direction or the other – sometimes inadvertently.

When rooted plants are destroyed, mucky bottoms get stirred up and re-suspend nutrients. Competition with algae ceases and foul blooms occur. If plant biomass is not mechanically removed, the rotting vegetation further adds to nutrient availability, turbidity, and algae growth.

Some Great Lakes Fish Populations at Risk from Low Nutrient Levels

Tue, 04 Jan 2022 22:00:36 +0000

As algal blooms flourish on the edges of the Great Lakes, lake management bodies look to cut down the flow of nutrients into the water that feeds the algae. But, as a recent report by the International Joint Commission explains, not all parts of the lakes suffer from too many nutrients — in fact, the deeper offshore waters aren’t getting enough.

In late June, the Commission’s Science Advisory Board released a report on the decline in nutrients in the offshore waters of the lakes and the harmful impact this decline is having on fish populations.

Phosphorus is an essential nutrient that fuels life in the Great Lakes ecosystems. The amount of phosphorus determines how many living things can survive in the lake, from tiny plankton up to top predator fish. And in every lake except Erie, the phosphorus levels in the offshore region — waters more than twenty meters deep — are below the targets established under the Great Lakes Water Quality Agreement between the United States and Canada.

Mechanical Harvesting Removes Water Chestnut on the Charles River

Tue, 21 Dec 2021 22:28:12 +0000

The Charles River Watershed Association and local citizens have obtained funding to conduct large-scale mechanical harvesting to remove roughly 50 acres of water chestnut and other invasive weeds.

The Charles River Lakes District in Massachusetts is a popular destination for canoeists, kayakers and rowers, but the pollution from stormwater runoff resulted in an increase in nutrients resulting in the growth of water chestnut, Eurasian watermilfoil and fanwort which interfered with those activities.

The weed harvesters have will harvest for a few weeks in August before the water chestnuts drop their seeds and will start up again in the spring of 2014.

HM-1020 Harvester Removes 16,000 Pounds of Weeds in 20 Minutes at Carter Lake

Tue, 21 Dec 2021 19:26:51 +0000

Carter Lake is an old oxbow lake of the Missouri River and is now an urban lake shared by two different cities (Omaha, Nebraska and Carter Lake, Iowa), in two counties (Douglas and Pottawattamie) and two states (Nebraska and Iowa).

A vital part of the area’s watershed, Carter Lake is a natural catch basin for storm runoff and melting snows. Excess nutrients being washed into the lakes leads to excessive aquatic plant growth.

The Aquarius Systems HM-1020 Aquatic Plant Harvester is the perfect solution for Carter Lake. The 1020 easily collected a full 16,000 lbs of cut vegetation in only 20 minutes of harvesting. This harvester holds so many weeds that it took two trucks to accept all of the harvested vegetation.

Zebra Mussels Can Increase Microcystis Harmful Algal Blooms

Fri, 17 Dec 2021 15:16:14 +0000

While invasive zebra mussels consume small plant-like organisms called phytoplankton, Michigan State University researchers discovered during a long-term study that zebra mussels can actually increase Microcystis, a type of phytoplankton known as “blue-green algae” or cyanobacteria, that forms harmful floating blooms.

Zebra mussels can filter out the Microcystis with other particles, but then they spit out the Microcystis because evidently it is unpalatable to them. The researchers suspected the zebra mussels were consuming competitors of Microcystis, which paved the way for the cyanobacteria to flourish under lower nutrient availability than it usually needs.