Daphnia carinata

Daphnia carinata belongs to the phylum Arthropoda, subphylum Crustacea, and order Cladocera. This species is a common component of freshwater zooplankton. In traditional field agriculture, it is not considered a pest as it does not consume plant tissues. However, in hydroponic, aquaponic, and commercial aquaculture systems, it can act as a nuisance organism that competes for nutrients and disrupts technical processes.

The primary habitat of this organism includes standing or slow-moving freshwater bodies, such as ponds, ditches, and artificial reservoirs. In an agronomic context, Daphnia carinata can colonize open hydroponic installations. While they do not directly attack plant roots or foliage, their high population density can mechanically clog filtration systems, pumps, and nutrient delivery lines.

The biology of the species is defined by rapid reproduction through parthenogenesis. Under favorable conditions, females produce offspring every few days, leading to exponential population growth. The life cycle involves nauplius stages and successive molts. The ability to produce dormant eggs, known as ephippia, allows the population to survive periods of drought or desiccation of the environment.

The damage to agricultural crops is indirect, stemming from the destabilization of the microbiological balance in nutrient solutions. High population densities lead to the rapid depletion of dissolved oxygen and vital nutrients intended for the plants. Furthermore, large masses of dying crustaceans cause water decay, leading to significant pH fluctuations that can severely stress or damage the root systems of the plants.

Protection and control measures include a combination of technical and biological sanitization strategies:

• Installation of fine-mesh mechanical filters at the intake of hydroponic systems.
• Implementation of UV sterilizers to eliminate microorganisms and small invertebrates in the nutrient solution.
• Regular and thorough disinfection of reservoirs using hydrogen peroxide solutions.
• Biological control through the introduction of natural predators, such as small fish or predatory insects, in integrated aquaponic modules.