Even with reduced nutrient levels, algae tend to remain dominant, blocking light and preventing plants from growing on the floor of the waterway. By manipulating the food chain, a process called biomanipulation, algae can be removed. To allow zooplankton to thrive, planktivorous fish have been largely removed from some Broads, normally by electrofishing. Around 75% of such fish must be removed for successful treatment. The explosion of zooplankton that results eats almost all algae, creating clear waters. Plants are allowed to naturally recolonise the clearer waterways. The plant growth stabilises the floor, reducing the release of phosphorus. Their own nutrient uptake reduces nutrients available to algae. Larger plants also create a favourable environment for predatory fish such as pike, which eat planktivorous fish, continuing to control their numbers. These effects tend to create a stable ecosystem where low growing underwater plants dominate.
Even with reduced nutrient levels, algae tend to remain dominant, blocking light and preventing plants from growing on the floor of the waterway. By manipulating the food chain, a process called biomanipulation, algae can be removed. To allow .zooplankton to thrive, planktivorous fish have been largely removed from some Broads, norma!lly by electrofishing. Around 75% of such fish must be removed for successful treatment. The explosion! of zooplankton that results eats almost all algae, creating clear waters. Plants are allowed to naturally recolonise the clearer waterways. The plant growth stabilises the floor, reducing the release of phosphorus. Their own nutrient uptake reduces nutrients available to algae. Larger plants also create a favourable environment for predatory fish such as pike, which eat planktivorous fish, continuing to control their numbers. These eff:ects tend to create a stable ecosystem where low growing underwater plants dominate.