DeepSea Zone high pressure cold temperature total darkness

Deep-Sea Zone • high pressure, cold temperature, total darkness • once believed to be completely devoid of life • now known to have some of the Earth’s strangest creatures • Gulper eels, giant squid, sea cucumbers

Deep-Sea Zone • zooplankton • free-floating microscopic animals • wait for night to migrate to the ocean’s surface to feed on phytoplankton

Estuaries • found at boundary between fresh water and salt water • salt marshes, mangrove swamps, lagoons, mouths of rivers • mixture of fresh water and salt water

Estuaries • supports a variety of life forms • usually shallow • sunlight penetrates the water completely • photosynthesis occurs at all levels • aquatic plants • supports many types of fishes, shrimps, and crabs

Energy and Nutrients: Building the Web of Life • Flow of energy through an ecosystem • one of most important factors in an ecosystem • 0. 1 percent of the sun’s energy reaches the earth • used by living things • responsible for producing organic matter

Energy and Nutrients: Building the Web of Life • energy absorbed by plants • 1/2 used immediately • 1/2 stored • animals eat plants • absorb small amount of the 1/2 stored by plants

Energy and Nutrients: Building the Web of Life • Energy cannot be recycled • flow not a cycle • Nutrients can be recycled through an ecosystem • when an animal dies, its matter does not disappear • decomposes and gets used by another organism

Flow of Energy • Sun is the ultimate source of energy for all living things • producers (photosynthetic organisms) make their own food • photosynthesis

Flow of Energy • Consumers • animals • get energy directly or indirectly from producers • primary consumers • herbivores

Flow of Energy • secondary consumers • feed on primary consumers • carnivores

Flow of Energy

Flow of Energy • Energy flows through an ecosystem from the sun to producers and then to consumers

Flow of Energy • plants and animals die • remains do not build up • decomposers • obtain energy from nonliving organic matter • bacteria, fungi

Flow of Energy • trophic level • feeding level • there is no limit to the number of trophic levels in an ecosystem • at each higher trophic level, less and less of the energy originally captured by the producers is available

Ecological Pyramids • represent the energy relationships among trophic levels • three types of ecological pyramids