Which of the following is NOT a characteristic of phytoplankton?

Phytoplankton are a critical component of aquatic ecosystems, and understanding their characteristics helps clarify their role in the environment. They are microscopic organisms, primarily composed of algae, that float in the water column, making them essential producers in aquatic habitats.

While phytoplankton thrive on nutrients, they do not consume nutrients from the soil. Instead, they use dissolved nutrients present in the water, such as nitrates and phosphates, which are generally washed into aquatic systems from surrounding land through runoff. This key distinction underscores the correct answer, as the interaction of phytoplankton with nutrients is based on the water content rather than direct soil consumption.

In addition to their nutrient absorption characteristics, phytoplankton contribute significantly to aquatic ecosystems. They are foundational to the food web, serving as food for a variety of aquatic organisms, including zooplankton, fish, and other marine life, while also generating oxygen through photosynthesis. Understanding that phytoplankton rely on water for their nutrient sources is essential for grasping their ecological significance and role in water-based environments.