Tropical oceans are generally characterized by low net primary productivity. What are three environments that are exceptions to this and what factors contribute to their higher productivity?

Question

What will be an ideal response?

Answer 1

Exceptions to the general pattern of low productivity in tropical oceans include: 1. Equatorial upwelling. Where trade winds drive westerly equatorial currents on either side of the equator, Ekman transport causes surface water to diverge toward higher latitudes. This surface water is replaced by nutrient-rich water from depths of up to 200 meters. Equatorial upwelling is best developed in the eastern Pacific Ocean.; 2. Coastal upwelling. Where the prevailing winds blow toward the equator and along western continental margins, surface waters are driven away from the coast. They are replaced by nutrient-rich waters from depths of 200 to 900 meters. This upwelling promotes high primary production along the west coasts of continents, which can support large fisheries.; and 3. Coral reefs. Organisms that comprise and live among coral reefs are superbly adapted to low-nutrient conditions, similar to the way certain organisms are adapted to desert life on land. Symbiotic microscopic algae living within the tissues of coral and other species allow coral reefs to be highly productive ecosystems. Coral reefs also tend to retain and recycle what little nutrients exist.