How do light, nutrients, and temperature interact to limit primary production in coastal ecosystems?

• A. Light limits photosynthesis in deeper or turbid waters; nutrients from rivers and upwelling supply phytoplankton; temperature controls metabolic rates; when nutrients are abundant and light is sufficient, production increases.
• B. Nutrients always limit production regardless of light.
• C. Light is never a limiting factor.
• D. Temperature has no effect on metabolism.

Answer: (A)