Common Duckweed
Lemna minor
The common duckweed is a perennial, herbaceous plant that floats on the water surface. It consists of one or a few lens-shaped fronds, each with a single root hanging into the water. This species is globally distributed and known for its extremely rapid vegetative growth under nutrient-rich conditions. It plays a central role in limnic ecosystems as a primary producer and oxygen supplier.
Details
Oxygen production
High oxygen production during daylight, but may hinder gas exchange at night or when the surface mat is too dense.
Habitat function
Serves as a nursery for amphibian larvae and as a substrate for microorganisms.
Nutrient uptake
Excellent uptake of nitrate, ammonium, and phosphate.
Food source for
Anatidae, cyprinid fish, moorhens, and invertebrates.
Human use
Used as protein-rich livestock feed, in wastewater treatment (phytoremediation), and as a model organism in biological research.
Ecology
Ecological role
Important primary producer, provides hiding places for aquatic insect larvae, and contributes to water purification through high nitrogen removal.
Natural predators
Waterfowl (especially ducks), grass carp, snails, and various aquatic insects.
Competitor species
Other duckweed species such as Great Duckweed (Spirodela polyrhiza) and filamentous algae.
Ecosystem service
Nutrient elimination from polluted waters, CO2 sequestration, and provision of biomass.
Threats
Herbicide input from agriculture and the destruction of small water bodies.
Scientific profile
Profile
Reproduction
Primarily vegetative through budding (frond production in lateral pouches), which can lead to a doubling of biomass within 2-3 days under optimal conditions. Generative reproduction via seeds is rare.
Protection & threats
Main threats
No significant threats; rather benefits from anthropogenic eutrophication. Locally threatened by herbicide use or extreme water body maintenance.