Which type of plankton forms the base of many aquatic food webs?

Phytoplankton are microscopic plants that are crucial in aquatic ecosystems, as they serve as the primary producers in many marine and freshwater food webs. These organisms are photosynthetic and convert sunlight into energy, forming the foundational level of the food chain. When phytoplankton photosynthesize, they produce oxygen and organic matter, which are essential for the survival of higher trophic levels, including herbivorous zooplankton, small fish, and larger marine animals.

The role of phytoplankton extends beyond being food; they also contribute to the regulation of carbon dioxide and oxygen levels in the water, influencing global climate as well. Their abundance and diversity are significant, as they can rapidly multiply, especially in nutrient-rich waters, providing a critical resource for many aquatic organisms. Thus, understanding the importance of phytoplankton helps illustrate how energy flows through aquatic ecosystems and maintains ecological balance.