AP BIOLOGY

Detailed explanation-1: -Coral reef ecosystem has highest gross primary productivity due to availability of large number of autotrophs per unit area.

Detailed explanation-2: -In aquatic ecosystems, coral reefs have the highest productivity.

Detailed explanation-3: -In coral reefs, primary production is tightly coupled with efficient utilization and regeneration of organic and inorganic nutrients, which allows an unusually high productivity in a nutrient poor environment (Muscatine and Porter, 1977; Hallock and Schlager, 1986).

Detailed explanation-4: -The rate at which energy or organic matter stored by producers in their bodies per unit area per unit time is called the net primary productivity of an ecosystem. The productivity of tropical rainforests is the highest.

Detailed explanation-5: -Net marine primary productivity is the amount of organic material available to support the consumers (herbivores and carnivores) of the sea. The standing crop is the total biomass (weight) of vegetation.