Rugose stonewort
Chara rudis
The Rugose stonewort is a large, perennial macroalga that primarily inhabits lime-rich, oligo- to mesotrophic lakes. It is characterized by a robust growth habit and often appears greyish-green due to heavy lime encrustation. The plant forms dense carpets on the lake floor and plays a crucial role in the nutrient cycling of clear hard-water lakes.
Details
Oxygen production
High; contributes significantly to oxygen saturation in the benthic zone.
Habitat function
Structural engineer; provides hiding places for zooplankton and serves as spawning substrate.
Nutrient uptake
High capacity for phosphate binding through co-precipitation with calcium carbonate.
Food source for
Important food source for waterfowl such as the Red-crested Pochard (Netta rufina).
Human use
Historically used in some cases as lime-rich fertilizer in agriculture.
Ecology
Ecological role
Primary producer, stabilization of the clear-water state through phosphate sequestration and sediment fixation.
Natural predators
Waterfowl, herbivorous fish, and various aquatic invertebrates.
Competitor species
Other macrophytes such as pondweeds (Potamogeton spp.) under increasing nutrient levels.
Ecosystem service
Water purification, carbon sequestration, provision of habitat for juvenile fish.
Threats
Eutrophication, water turbidity, mechanical disturbances from boat traffic and shore engineering.
Scientific profile
Profile
Reproduction
Monoecious. Generative reproduction via oogonia and antheridia, forming oospores as resting stages. Vegetative reproduction occurs through shoot fragmentation and occasionally via bulbils on the rhizoids.