Written by Industry Expert, Shannon Junior, Senior Business Development Consultant and Aquatic Ecologist
Beneficial bacteria occur naturally in lakes and ponds, and are the microbes responsible for processing dead organic material. There are many different types of bacteria, which work in different ways to break down organic compounds. Aerobic bacteria use oxygen and rapidly break down organic compounds. Anaerobic bacteria are able to work without oxygen, but work much more slowly. Both types of bacteria produce enzymes that allow them to break down organic compounds and take them into their cells as nutrients. Many bacteria also perform denitrification, transforming nitrate into nitrogen gas and removing it from the pond system. They can also convert soluble phosphorus from the water column into calcium phosphate and calcium iron phosphate, which are insoluble minerals that are not available to most types of pond algae.
Since the bacteria convert nutrients into unavailable forms, they can be beneficial in reducing nuisance algae blooms in lakes and ponds. In fresh water, phosphorus is generally the limiting nutrient for algal growth. The ratio of nitrogen to phosphorus determines the types of algae that will grow and thrive in a pond. In situations where there is excess phosphorus, nuisance species of filamentous and bluegreen algae (cyanobacteria) will dominate the waterbody instead of the beneficial planktonic green algae that form the base of the food web. The bacteria themselves can also contribute to the food web, becoming a food source for zooplankton and benthos, which then become food for fish and other organisms.