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Mangroves are large woody trees with a dense, complex root system that grows downward from the branches Mangroves are the dominant plant of the tropical and subtropical intertidal area Distribution of the trees is largely controlled by air temperature, exposure to wave and current attack, tidal range, substrate and sea water chemistry Detritus from the mangrove forms the base of the food chain Human Actions have reduced wetlands to less than half of their land area Draining for agriculture Draining for housing/urban development Draining for mosquito prevention Pollution due to dumping and runoff Fig. 11.36a, p.288 Fig. 11.36b, p.288 Clean Water Act Protects wetlands by preventing dredge and fill operations in nations waters including wetlands Protected under water quality clauses of clean Water Act National pollutant discharge elimination Executive Order 11990 No Net Loss – protects wetlands by requiring restoration or mitigation of wetlands lost by development. cover about three-fourths of the Earth’s surface and include oceans, coral reefs, and estuaries algae supply much of the world’s oxygen supply and take in a huge amount of atmospheric carbon dioxide evaporation of the seawater provides rainwater for the land largest of all the ecosystems dominate the Earth’s surface separate zones Coastal Estuaries and wetlands Intertidal Pelagic Abyssal Benthic great diversity of species richest diversity of species even though it contains fewer species than there are on land Large volumes of fresh water mix with salt water Temperature and salinity levels vary widely due to Daily tides Seasonal variations of flow Unpredictable flow from freshwater sources Some of the world’s most productive ecosystems. Coastal wetland Inundated with salt water as tides change Salt tolerant plants Cordgrass Switchgrass Glasswort/saltwort enclosed body of water formed where freshwater from rivers and streams flows into the ocean, mixing with the salty sea water places of transition from land to sea, and from fresh to salt water influenced by the tides, but protected from the full force of ocean waves, winds, and storms by the reefs, barrier islands, or fingers of land, mud, or sand that define an estuary's seaward boundary Subdivided into three types based upon the relative importance of river inflow and tidal mixing. Salt-wedge estuaries are dominated by the outflow from rivers. Partially-mixed estuaries are dominated by neither river inflow nor tidal mixing. In well-mixed estuaries tidal turbulence destroys the halocline and water stratification. Estuaries are extremely fertile because nutrients are brought in by rivers and recycled from the bottom because of the turbulence. Stressful conditions and abundant nutrients result in low species diversity, but great abundance of the species present. Despite abundance of nutrients, phytoplankton blooms are irregular and the base of the food chain is detritus washed in from adjacent salt marshes. Estuaries are sometimes called “marine nurseries” habitats for many juvenile organisms, especially for fishes many fish are born and grow up in estuaries migrate to the open ocean Wildlife Habitat Recreation where the ocean meets the land sometimes submerged and at other times exposed waves and tides come in and out communities are constantly changing rocky coasts Where only highest tides reach submerged during high tide not as stratified waves keep mud and sand constantly moving more diverse array of algae and very few algae and plants can establish themselves bottom of the intertidal zone the fauna include worms, clams, predatory crustaceans, crabs, small animals, such as herbivorous snails, crabs, sea stars, and small fishes sandier shores stratified vertically a few species of algae and mollusks only exposed during the lowest tides, many invertebrates, fishes, and seaweed can be found and shorebirds. much stronger than wind decide what grows where shores classified by amount of wave action Exposed shores – receive full brunt of the ocean for most or at least some of the time Semi-exposed shores – sheltered by barrier islands but still have to cope with waves Sheltered shores – shelter of peninsulas and inshore islands Enclosed shores river mouths and estuaries completely sheltered by either a protective rocks or a sand bar Form in clear, warm, coastal waters Occupy only about 0.1% of worlds ocean Most diverse and productive ecosystems Home to one fourth the marine species Attached organisms give reef structure Corals, algae and sponges Fish Other small organisms that bore in or live within the nooks of the coral. Human impacts Species loss and endangerment Overfishing Habitat destruction Pollution Marine and Freshwater Habitat loss and degradation Overfishing Nonnative species Pollution and Global Warming Protect endangered and threatened species Establish protected areas Integrated coastal management Regulating and preventing ocean pollution Sustainably managing marine fisheries Example: Sea Turtles Lost due to Degradation of beach habitat Taking of eggs Used as food, medicine, jewelry and leather Unintentional capture and drowning Protected by: Beach protection Nest watchers US ESA TEDs CITES 1979 Global treaty on Migratory Species US Marine Mammal Protection Act US Endangered Species Act US Whale Conservation and protection act International Convention on Biological Diversity PMS – areas of coastal regions controlled by the nation Sovereignty of the 12 miles off shore Jurisdiction of 200 mile Economic Zone Benefits of these areas: Fish populations increase Fish size increases Fish reproduction triples Species diversity is 23% higher Community Based effort to develop and use coastal resources sustainable Identify shared problems and goals Find workable and cost effective solution that preserve biodiversity and environmental quality while meeting economic and social needs Develop better measurement and models for projecting fish populations and controlling fishing methods and access to fisheries Methods: Maximum sustained yield Optimum sustained yield Multispecies management Large marine system management Precautionary principle MSY – uses a mathematical model to project the max number of fish that can be harvested Leads to collapse of fish populations OSY Takes into account interactions with other fish species provide more room for error Is often ignored Multispecies management/Large Marine Systems Complex computer models that take into account competitive and predator-prey interactions in estimating fish catch International and National Laws Uses the Economic Exclusion Zones Community based comanagement Sets quotas for species Divides quotas among communities Limit fishing seasons and type of gear Individual transfer quotas Fishery Regulations Economic approaches Bycatch Protected Areas Nonnative invasions Consumer information Aquaculture