This is a photosynthetic cyanobacteria and free-floating algae that form the base of most aquatic food webs.

The most productive zone of the lake where photosynthesis is greatest.

Wetlands serve as ground water recharging areas that trap and hold pollutants in the flooded soil which cleanse and purify the water. This environmental function of wetland is known as ___________.

A coastal body of water partly surrounded by land with access to open ocean and large supply of freshwater from rivers.

The tropical equivalent of salt marshes.

The part of the marine ecosystem which refers to the shoreline area between low and high tide  that is considered to be the transitional zone between land and ocean. 

The flowering plants that have adapted complete submersion in ocean water. 

The largest brown algae that are common in cooler temperate marine waters of the Northern and Southern Hemisphere. 

The symbiotic dinoflagellates that live and photosynthesize in the tissues of coral animals.

The part of the open ocean that covers the deep ocean basin (the ocean floor at depths more than 200m) and considered to be the largest marine environment and contains 75% of the oceans water.

The upper part of the neritic province which extends from the surface to a depth of about 100m where enough light penetrates to support photosynthesis. 

The portion of the ocean without sunlight where many animals have illuminated organs that enable them to see one another for mating or to capture food. 

The transition zone where two communities or biomes meet and intergrade. 

8% of the world's fish species live in this reef along the northeastern coast of Australia.

The part of the benthic environment that extends to a depth of 4000m to 6000m.