Which of the following is NOT a physical control method for managing aquatic pests?

Chemical fertilizers are substances added to promote plant growth, and while they can affect water quality and plant health indirectly, they do not represent a physical method of control for managing aquatic pests.

In contrast, mechanical harvesting, water level management, and manual removal of plants are all considered physical control methods. Mechanical harvesting involves using machines to physically remove unwanted plants from water bodies. Water level management can influence the habitat and growth patterns of aquatic pests by altering the conditions under which they thrive. Manual removal refers to the direct physical action of pulling out plants or pests, thereby reducing their population.

Understanding these distinctions is crucial for effective pest management and helps in selecting appropriate control methods that align with environmental goals and regulatory requirements.