© Cengage Learning 2015 Saltwater ecosystems –Provide major ecosystem and economic services –Are irreplaceable reservoirs of biodiversity 8-2 Why Are Marine Aquatic Systems Important?

Fig. 8-5, p. 170 Natural Capital Marine Ecosystems Ecological Services Economic Services Climate moderation Food CO 2 absorption Pharmaceuticals Nutrient cycling Harbors and transportation routes Reduced storm impact (mangroves, barrier islands, coastal wetlands) Minerals Energy from waves and tides Recreation and tourism Employment Biodiversity: species and habitats Water purification Oxygen supplied through photosynthesis

© Cengage Learning 2015 Estimated $12 trillion per year in goods and services (Equal to US gross domestic product) Enormous reservoirs of biodiversity Helps to sustain the four major components of the earth’s biodiversity (Species, Genetic, Functional, Ecological) Oceans Provide Vital Ecosystem and Economic Services

© Cengage Learning 2015 There are three major marine life zones: –Coastal zone –Open sea –Ocean bottom Oceans Provide Vital Ecosystem and Economic Services

© Cengage Learning 2015 Coastal zone -- Warm, nutrient rich, shallow water -- Extends from shore to edge of continental shelf Coastal Zone

© Cengage Learning 2015 Coastal zone -- Warm, nutrient rich, shallow water -- Extends from shore to edge of continental shelf -- Occupies only 10% of ocean area -- Contains 90% of all marine species (site of commercial fisheries) -- Has high NPP* from ample sunlight and nutrients -- Include coral reefs, estuaries, coastal marshes, mangrove forests, sea grass beds, intertidal zone, and sandy shores Coastal Zone Coastal Zone *NPP- net primary productivity

© Cengage Learning 2015 Fig. 8-6, p. 171 High tide Low tide Coastal Zone Open Sea Depth in meters Sea level Estuarine Zone Euphotic Zone Photosynthesis Continental shelf Bathyal Zone Twilight Water temperature drops rapidly between the euphotic zone and the abyssal zone in an area called the thermocline. Abyssal Zone Darkness Water temperature (°C)

© Cengage Learning 2015 Estuaries –Where rivers meet the sea –Where freshwater mixes with saltwater (brackish water) Coastal Zone

© Cengage Learning 2015 Estuaries –Contains large amounts of nutrients (carried there by rivers) so HPP –One of the most biodiverse ecosystems – Known as "nurseries of the sea" - the protected environment and abundant food provide an ideal location for fish and shellfish to reproduce. –Many species of birds depend on estuaries for food and nesting areas(egret, heron, osprey). –Marine mammals also use estuaries as feeding grounds and nurseries (seal, otter). –Abundant plant life (and filter feeders) filter contaminates from water Coastal Zone

© Cengage Learning 2015 Estuaries phytoplankton

© Cengage Learning 2015

The Chesapeake Bay is the largest estuary in North America and the second largest estuary in the world. The watershed covers 64,000 square miles and includes six states: Delaware, Maryland, New York, Pennsylvania, Virginia and West Virginia. From North to South the Bay is 195 miles long, the width of the bay ranges from 4 miles to 30 miles. The Bay and its tidal tributaries have over 11,000 miles of shoreline; this is more than the entire West coast. There are about 150 major rivers and streams that are in the Chesapeake drainage basin. The Susquehanna River provides half the amount of freshwater coming into the Bay. Chesapeake Bay has an average depth of 21 feet and the deepest part of the Bay is 174 feet. Its salinity ranges from completely freshwater in the northern part of the Bay to areas that are as salty as the ocean near the mouth of the bay. There are more than 15 million people that live within the Chesapeake Bay basin. The Bay serves as a commercial and recreational resource for those that live within the basin. Commercially, the Bay produces about 500 billion pounds of seafood a year, it is one of the largest sources for seafood in America. The Estuary provides a habitat for over 2500 species of plants and animal life, including over 200 species of fish. The Chesapeake Bay also is home to two of the five major ports in North America. Baltimore, Maryland in the Upper Bay and Hampton Roads, Virginia in the Lower Bay. These ports are economically important to the communities that are part of the Chesapeake Bay area. The Estuary is so big that people living within the basin are only a few minutes from one of the rivers or streams that flow into the Bay. Therefore human activities on land have a substantial impact on the Bay. The Chesapeake Bay was the first estuary in the nation targeted for restoration due to human impact.

© Cengage Learning 2015 Estuaries

© Cengage Learning 2015 Coastal wetlands –Coastal land covered with water all or part of the year  Salt Marshes  Mangrove Forests Coastal Zone

© Cengage Learning 2015 Salt Marsh

© Cengage Learning 2015 Salt Marshes -- Occur along the coast in temperate climates Some are located in estuaries -- One of the most productive ecosystems (Contains large amounts of nutrients carried there by rivers; so HPP) -- Contain mostly grasses and sedges (grass-like; have solid stems) Coastal Zone

© Cengage Learning 2015 Salt Marshes -- The soil consists of deep mud and peat. Peat is made of decomposing plant matter. -- Peat provides a steady source of food for many organisms. Peat is a source of food for decomposers(bacteria, fungi) and for bottom-dwellers such as worms, fish, crabs, and shrimp. -- Also serve as nursery for many marine species… the grasses provide shelter from predators and peat serve as nourishment for the young. -- Protect water quality; marsh grasses and peat filter excess nutrients and contaminates from the water -- Protect shorelines from erosion by buffering wave action and trapping sediments. Coastal Zone

© Cengage Learning 2015 SALT MARSH FOOD WEB

© Cengage Learning 2015

Salt marshes are much scarcer on the West Coast than in the East. This is because there are fewer large bays and there are more rocky coasts. Development has destroyed many of the Pacific Coast salt marshes.

© Cengage Learning 2015 Mangrove Forests -- Occur along the tropical and subtropical coast; Some are located in estuaries -- Contain Mangrove trees whose roots are submerged in water. Mangrove trees are salt tolerant and help protect the coastlines from erosion and storm damage. Coastal Zone

© Cengage Learning 2015 Mangrove Forest -- Very diverse ecosystem (Constantly replenished with nutrients transported by fresh water runoff from the land) -- Falling leaves and trapped organic matter provide nutrients -- Provide food and shelter for many marine organisms Support bacteria, worms, protozoa, filter feeders (barnacles. clams, oysters) which in turn feed fish and shrimp, which support wading birds, pelicans, and the endangered Crocodile. Coastal Zone

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Ding Darling National Wildlife reserve

© Cengage Learning 2015 Sea Grass Beds -- Consist of grass-like flowering plants that live completely submerged in marine and estuarine waters along the coastline species of seagrasses worldwide (7 species in Florida) -- They and the organisms that grow on them are food for many marine animals and water birds -- They provide shelter for small fishes, crustaceans and others. Coastal Zone Coastal Zone

© Cengage Learning 2015 Sea Grass Beds Some animals, such as manatees, urchins, conches and sea turtles, eat seagrass blades. Other animals derive nutrition from eating algae and small animals that live upon seagrass leaves. Bottlenose dolphins and a variety of wading and diving birds also use seagrass beds as feeding grounds. Seagrass-based detritus formed by the microbial breakdown of leaves and roots is also an important food source.

© Cengage Learning 2015 Intertidal Zone -- Area of shore between high and low tides Coastal Zone

© Cengage Learning 2015 Intertidal Zone -- Organism have adaptations necessary to deal with: Being immersed in high tide; left hot and dry during low tide Avoid being swept away or crushed by waves Changes in salinity when heavy rainfall dilutes saltwater -- Intertidal organisms hold on, dig in, or hide(in shell) Coastal Zone

© Cengage Learning 2015 Rocky Intertidal Zone

© Cengage Learning 2015 Beach flea Peanut worm Tiger beetle Blue crab Clam Dwarf olive High tide Sandpiper Ghost shrimp Silversides Low tide Mole shrimp White sand macoma Sand dollar Moon snail Sea star Hermit crab Shore crab High tide Periwinkle Sea urchin Anemone Mussel Low tide Sculpin Barnacles Kelp Sea lettuce Monterey flatworm Nudibranch Stepped Art Fig. 8-11, p. 180 Rocky shore Sandy shore

© Cengage Learning 2015 Coral Reefs -- found in warm, shallow waters -- Are among the oldest, most diverse, and most productive ecosystem. -- Marine equivalent of tropical rain forests -- Complex interactions among their diverse populations of species -- Home to ¼ of all marine species Coastal Zone Coastal Zone

© Cengage Learning 2015 Open sea -- Beyond edge of continental shelf -- Sharp increase in water depth Oceans Provide Vital Ecosystem and Economic Services

© Cengage Learning 2015 Open sea divided into three vertical zones: Euphotic zone Bathyal zone Abyssal zone The Open Sea and the Ocean Floor Host a Variety of Species

© Cengage Learning 2015 Euphotic zone Brightly lit upper zone Nutrient levels low; Dissolved oxygen levels high Upwelling brings nutrients from below Phytoplankton (carry out 40% of all photosynthesis) Zooplankton, most fish, others The Open Sea and the Ocean Floor Host a Variety of Species

© Cengage Learning 2015 Bathyal zone Dimly lit middle zone Amphipods, fish, squid, octopus, sharks, The Open Sea and the Ocean Floor Host a Variety of Species

© Cengage Learning 2015 Abyssal Zone and Ocean Bottom -- Dark and cold lowest zone -- No photosynthetic producers; Little dissolved oxygen -- High levels of nutrients -- Marine snow – showers of dead and decaying organisms that drift down from upper levels of ocean -- Deposit feeders (eat mud and extract nutrients); worms -- Filter feeders (pass water thru bodies) sponges, clams The Open Sea and the Ocean Floor Host a Variety of Species

© Cengage Learning 2015 Abyssal Zone and Ocean Bottom -- fish, squid, crustaceans, starfish, jellyfish The Open Sea and the Ocean Floor Host a Variety of Species Basket star sea pig sea spider

© Cengage Learning 2015 Open sea Oceans Provide Vital Ecosystem and Economic Services -- Low NPP except in upwelling areas -- It makes the largest contribution to the earth’s overall NPP, because it covers so much of the earth’s surface.

© Cengage Learning 2015 Reefs are being destroyed and damaged worldwide Ocean acidification –Oceans absorb CO 2 –CO 2 reacts with ocean water to form a weak acid that decreases levels of carbonate ions (CO 3 2- ) needed to form coral Coral Reefs Are Amazing Centers of Biodiversity

© Cengage Learning 2015 Human activities –Threaten aquatic biodiversity –Disrupt ecosystem and economic services provided by saltwater systems 8-3 How Have Human Activities Affected Marine Ecosystems?

© Cengage Learning 2015 Major threats to marine systems include: –Coastal development –Overfishing; use of fishing trawlers –Runoff of nonpoint source pollution –Point source pollution –Habitat destruction –Introduction of invasive species –Pollution of coastal wetlands and estuaries Human Activities Are Disrupting and Degrading Marine Systems

Fig. 8-12, p. 176 Natural Capital Degradation Major Human Impacts on Marine Ecosystems and Coral Reefs Marine EcosystemsCoral Reefs Half of coastal wetlands lost to agriculture and urban development Ocean warming Over one-fifth of mangrove forests lost to agriculture, aquaculture, and development Soil erosion Rising ocean acidity Beaches eroding due to development and rising sea levels Bleaching Algae growth from fertilizer runoff Ocean bottom habitats degraded by dredging and trawler fishing Increased UV exposure Rising sea levels At least 20% of coral reefs severely damaged and 25–33% more threatened Damage from anchors and from fishing and diving

© Cengage Learning 2015 Largest estuary in the U.S. –Polluted since 1960 Large population increase Point and nonpoint sources raised pollution Phosphate and nitrate levels too high Excess sediments from runoff and decreased vegetation Case Study: The Chesapeake Bay – an Estuary in Trouble

© Cengage Learning 2015 Oysters, a keystone species, greatly reduced 1983: Chesapeake Bay Program –Integrated coastal management with local, state, and federal governments, as well as citizens’ groups 2008 update: –25 years and $6 billion –Program failed to meet goals Case Study: The Chesapeake Bay – an Estuary in Trouble (cont’d.)

Drainage basin No oxygen Low concentrations of oxygen Fig. 8-13, p. 177

© Cengage Learning 2015