Pond Boss Forums AQUATIC VEGETATION Balance of plants in the environment Plant Impact on Winter Kill

Pond depth and water clarity also play a big rolls as to how quickly the rooted plants become a problem under ice and snow cover. Water clarity at freeze up determines how much light can enter ice or open water from an aerator. Water clarity affects how deep the plants will grow in the pond. The deeper the plant growth the faster that oxygen will be consumed in the darkness of snow cover because more plant mass to decay is present. The deeper the pond the more dissolved oxygen(DO) that will be in the pond before all DO is consumed.

Generally during winter it is the phytoplankton not rooted plants that provide DO to the pond if the microscopic phytoplankton receives sunlight. However in ponds with more rooted plants the fewer numbers of phytoplankton. The two types of plants compete with each other. Rooted plants have been shown to chemically suppress growth of phytoplankton. There are winter phytoplankton species that thrive in cold water. A pond only 8 ft deep is a lot more prone to winter kill compared to a pond 16-24ft deep. Larger volumes hold more DO for longer periods. The amount of organic decomposition starting at the bottom is where DO is lost first during winter.