Mixotrofisia

Mixotrofisia, also known as mixotrophy, refers to a nutritional strategy in which an organism derives energy and carbon from more than one source. Typically, mixotrophs combine photosynthesis (phototrophy) with heterotrophic processes such as ingestion of prey or uptake of dissolved organic matter. In some cases, organisms can switch between modes or use both simultaneously, providing flexibility under changing light and nutrient conditions.

In phototrophic mixotrophs, light energy drives photosynthesis while inorganic carbon is fixed, and the organism also acquires additional nutrients by consuming prey or absorbing dissolved organic compounds. In other forms, mixotrophs rely on organic carbon for growth but supplement energy or nutrients through photosynthesis or inorganic processes. The degree of reliance on photosynthesis versus heterotrophy varies among species and environments.

Mixotrophy is widespread among protists and occurs in several major groups, including euglenoids (such as Euglena), chrysophytes (golden algae), and many dinoflagellates. It is especially common in aquatic systems where light is variable or nutrients are scarce, allowing organisms to exploit multiple resources.

Ecologically, mixotrophs contribute to primary production while also recycling nutrients via heterotrophy, influencing carbon flow and nutrient dynamics in microbial food webs. They can affect bloom formation, nutrient uptake, and the efficiency of energy transfer in lakes and oceans.

Research methods for studying mixotrophy include stable isotope tracing (for carbon and nitrogen uptake), culture experiments to distinguish photosynthetic and heterotrophic activity, and molecular or microscopic approaches to identify the dominant nutritional mode in a given context.