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Marine Pollution. Human Effects on the Marine Environment. Alteration of bottom by dredging; shoreline alteration and filling Introduction of toxic substances Eutrophication through nutrient enrichment Thermal pollution from power plants Invasive or nonindigenous species
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Human Effects on the Marine Environment • Alteration of bottom by dredging; shoreline alteration and filling • Introduction of toxic substances • Eutrophication through nutrient enrichment • Thermal pollution from power plants • Invasive or nonindigenous species • Important Marine Legislative Acts
Acute vs. Chronic Pollution • Acute (short term) – ex. is an oil spill, the effects of which diminish with time • Chronic (long term) – ex. is nutrient input
Pollution – Point and Non-Point • Point source – from a single sewer pipe or factory waste-water outfall • Non-point source – effects cannot be attributed to any single spot and thus harder to control; exs. Runoff of toxic substances or fertilizer after a rain;
Using Organisms to Monitor Pollution • Determining species diversity – diversity usually declines in strongly polluted habitats • Bioassay species; exposure of certain species to varying concentrations of toxic materials; crabs and mussels often used • Degree of evolved resistance
Biodegradeable vs. Inert Toxic Substances • Inert toxic substances biomagnify up the food chain whereas biodegradeable materials do not; • Substances that biomagnify • heavy metals - cadmium, mercury and lead • Pesticides made of chlorinated hydrocarbons – kepone, DDT, dieldrin, chlordane, dioxin • PCB’s - used as lubricants
Important Toxic Substances • Sources- mines, sewage, insecticides, fungicides and industry • Oil • Mercury (methylmercury) – see the story in the text on “Minamata disease” • Cadmium – from electroplating and battery manufacturing plants • Lead • Chlorinated hydrocarbons • PCB’s
Oil Pollution - Sources • Leaks from marine terminals and in harbors • Leaks from offshore drilling • Leaks from breakup of oil tankers and barges • Washout of oil into storm drains
Potential Results of Pollution • A reduction in biodiversity • Stress on populations that are already threatened or endangered
Nutrient Enrichment Leads To … • Algal blooms which can lead to … • High antiherbivory toxin production such as • red tides (Dinoflagllates) which effect shellfish and vertebrates • Populations of Pfisteria
Dinoflagellates cause Green Brown Yellow Too!
Opportunistic Highly adaptable Cysts Free-swimming Parasitic to fish Toxins 24 recognizable life stages! Did these protists evolve in 1997?
Dinoflagellates “Toxic Tides” Are these “new” species of protists? Are they opportunistic protists?
Dinoflagellates “Toxic Tides” What environmental stimuli promote their growth?
Invasive Species • Sources of invasive species • Ship ballast • Aquaculture • Academia and public aquaria • Pet and aquarium stores • Recreational boating and fishing • Special activities – transporting dry docks, oil rigs and barges
Invasive Species in Coastal Regions – Questions Asked • Questions related to Species Richness • What species are in our estuaries? • How many are non-native in each estuary? • How is species composition changing over time? • Which regions have the highest rate of new invasions? • Which taxa have the highest proportion of non-native to native species?
Questions Cont’d. • Questions on Impact • Impacts on ecosystem productivity, biodiversity, community structure, and ecologically sensitive habitats? • Which non-native species are a particular threat to native communities? • How does human-mediated habitat disturbance and hydrological alteration modify the impact of non-native species?
Factors That Mediate Invasion Success • How is propagule pressure related to invasion success? • Which vectors are responsible for the most invasions, or those of the most high-impact invaders? • Are different taxa more likely to be introduced by different vectors? • ?????????????????
Invaders – Intrinsic Traits • How does the live history stage or genetics of a species affect its invasive abilities? • How does the ecological role of a species affect the rate and pattern of its spread? • Are populations of selected introductions genetically isolated from other populations?
Marine Legislation Six Important Acts
Important Legislation • National Marine Sanctuaries Act - (1972) (NMSA) • Fisheries Management and Conservation Act (1976) • Clean Water Act – (1977) • Endangered Species Act • Estuaries and Clean Water Act (2000) • The Oceans Act (2000)
National Marine Sanctuaries Act of 1972 • Authorizes the Sec. of Commerce to designate and manage areas of the marine environment with nationally significant aesthetic, ecological, historical or recreational values as National Marine Sanctuaries . • The primary objective is to protect marine resources while facilitating “compatible” public and private uses of those resources.
Fisheries Management and Conservation Act - 1976 • The primary law dealing with fisheries resources and fishing activities in federal waters (extends from edge of State waters out to the 200 mile limit). • Primary goals include conservation and management of fisheries resources, development of U./S. domestic fisheries and phasing out foreign fishing activities within the 200 mile conservation zone adjacent to the U.S. coastline.
Clean Water Act of 1977 • Unlawful to discharge any pollutant from a point source into navigable waters unless a permit (NPDES) is obtained • EPA has authority to set effluent standards • Also unlawful to discharge dredged or fill materials into wetlands without a permit
Endangered Species Act • Provides for the conservation of threatened and endangered plants and animals and the habitats in which they are found. • The law prohibits any action, administrative or real, that results in a “taking” of a listed species, or adversely affects habitat.
Estuaries and Clean Waters Act of 2000 • Encourages the restoration of estuary habitat through more efficient project financing and enhanced coordination of Fed. And non-Fed. restoration programs • Establishes a Estuary Habitat Restoration Council to develop a comprehensive approach
Oceans Act of 2000 • Establishes a commission to make recs. for coordinated and comprehensive national ocean policy. • Issues will include coastal hazards, stewardship, marine pollution prevention, enhancing marine-related commerce and transportation, research and education and the use of technology to address coastal issues.