Chapter 7. Aquatic Ecology: Biodiversity in Aquatic Systems Miller – Living in the Environment 13th ed.

Who lives in a pineapple under the sea?

Aquatic Life Zones Saltwater or Marine estuaries, coastlines, coastal marshes, mangrove swamps, and oceans Freshwater lakes and ponds, streams and rivers, inland wetlands

Aquatic Environments 90% 50% Saltwater and freshwater aquatic life zones cover almost three-fourths of the earth’s surface 90% 50%

Lakes Rivers Coral reefs Mangroves

Types of organisms Phytoplankton Zooplankton Nekton Benthos cyanobacteria and algae Zooplankton primary and secondary consumers Nekton Swimming consumers (fish, turtles, and whales) Benthos bottom dwellers Barnacles and oysters Worms Lobsters and crabs Decomposers bacteria

Power to the Plankton Clip

© 2004 Brooks/Cole – Thomson Learning Advantages Disadvantages Physical support from water buoyancy Fairly constant temperature Nourishment from dissolved nutrients Water availability Easy dispersal of organisms, larvae, and eggs Less exposure to harmful UV radiation Dilution and dispersion of pollutants Can tolerate a narrow range of temperatures Exposure to dissolved pollutants Fluctuating population size for many species Dispersion separates many aquatic offspring from parents

Factors Limiting Life in Aquatic Life Zones Temperature Access to sunlight Euphotic zone Dissolved oxygen 5 ppm Available nutrients Shallow water upwelling

Limiting Factors O2 CO2 500 2,000 1,000 4,000 Depth (meters) Limiting Factors 500 © 2004 Brooks/Cole – Thomson Learning 2,000 O2 1,000 CO2 4,000 Depth (meters) Depth (feet) 1,500 6,000 2,000 1.5 3.0 4.5 6.0 7.5 O2 90 94 98 102 106 110 CO2 Concentration of dissolved gas (parts per million by weight)

Harbors and transportation routes Natural Capital Marine Ecosystems Ecological Services Economic Services Climate moderation Food CO2 absorption Animal and pet feed Nutrient cycling Pharmaceuticals Waste treatment Harbors and transportation routes Reduced storm impact (mangroves, barrier islands, coastal wetlands) Coastal habitats for humans Figure 6.4 Natural capital: major ecological and economic services provided by marine systems. Scientists estimate that marine systems provide $21 trillion in goods and services per year—70% more than terrestrial ecosystems. QUESTION: Which two ecological services and which two economic services do you think are the most important? Habitats and nursery areas Recreation Employment Genetic resources and biodiversity Oil and natural gas Minerals Scientific information Building materials

The Coastal Zone: Where Most of the Action Is Warm, nutrient-rich, shallow water that extends from the high-tide mark on land to the gently sloping, shallow edge of the continental shelf. The coastal zone makes up less than 10% of the world’s ocean area but contains 90% of all marine species. Provides numerous ecological and economic services. Subject to human disturbance.

The Coastal Zone High tide Coastal Zone Open Sea Sun Low tide Sea level Photosynthesis Euphotic Zone Estuarine Zone Continental shelf Bathyal Zone Twilight The Coastal Zone Abyssal Zone Figure 6.5 Natural capital: major life zones in an ocean (not drawn to scale). Actual depths of zones may vary. Darkness Fig. 6-5, p. 130

What are estuaries and coastal wetlands? Estuary Coastal water where seawater mixes with fresh water and nutrients from rivers, streams, and runoff Coastal Wetlands Land areas covered with water all or part of the year

Coastal Wetlands River mouths Inlets Bays Sounds Mangrove forest swamps Salt marshes

Salt Marsh Figure 6.7 Natural capital: some components and interactions in a salt marsh ecosystem in a temperate area such as the United States. When these organisms die, decomposers break down their organic matter into minerals used by plants. Colored arrows indicate transfers of matter and energy between consumers (herbivores), secondary or higher-level consumers (carnivores), and decomposers. Organisms are not drawn to scale. The photo below shows a salt marsh in Peru.

Mangrove Forests Are found along about 70% of gently sloping sandy and silty coastlines in tropical and subtropical regions.

Estuaries and Coastal Wetlands: Centers of Productivity Provide ecological and economic services: Filter toxic pollutants, excess plant nutrients, sediments, and other pollutants. Reduce storm damage by absorbing waves and storing excess water produced by storms and tsunamis. Provide food, habitats and nursery sites for many aquatic species.

Salt Marsh Ecosytem Peregrine falcon Herring gulls Snowy egret Producer to primary consumer Snowy egret Cordgrass Primary to secondary consumer Short-billed dowitcher Marsh periwinkle Secondary to higher-level consumer Phytoplankton Smelt All producers and consumers to decomposers Zooplankton and small crustaceans Soft-shelled clam Salt Marsh Ecosytem Clamworm Bacteria

Rocky and Sandy Shores: Living with the Tides ADD to NOTES Organisms experiencing daily low and high tides have evolved a number of ways to survive under harsh and changing conditions. Gravitational pull by moon and sun causes tides. Intertidal Zone: area of shoreline between low and high tides.

Rocky Shore Beach Low tide Sea star Hermit crab Shore crab Barnacles High tide Periwinkle Sea urchin Anemone Mussel Low tide Sculpin Barnacles Kelp Sea lettuce Monterey flatworm Nudibranch

Sandy beach High tide Low tide White sand macoma Sand dollar Beach flea Sandy beach Peanut worm Tiger beetle Blue crab Clam Dwarf olive High tide Sandpiper Ghost shrimp Silversides Mole shrimp Low tide White sand macoma Sand dollar Moon snail

Taller shrubs and trees Barrier Islands Ocean Beach Intensive recreation, no building Primary Dune No direct passage or building Trough Limited recreation and walkways Secondary Dune No direct passage or building Back Dune Most suitable for development Bay or Lagoon Intensive recreation Bay shore No filling Grasses or shrubs Taller shrubs Taller shrubs and trees Long, thin, low off-shore islands that generally run parallel to the shore.

Coral Reefs Polyps Zooxanthellae Soft bodies Calcium carbonate crust Algae Color Food Oxygen

Importance of coral reefs Removing CO2 from atmosphere Natural barrier Waves and storms Allows oceans to replenish beach sand Supports marine life Source of global fish catch Provides food, jobs, and building materials for world’s poorest countries Supports fishing and tourism Scientific research

Coral Reef Producer to primary consumer Primary to secondary consumer Gray reef shark Producer to primary consumer Sea nettle Green sea turtle Fairy basslet Primary to secondary consumer Blue tangs Parrot fish Sergeant major Algae Brittle star Banded coral shrimp Hard corals Secondary to higher-level consumer Phytoplankton Coney Symbiotic algae Blackcap basslet Zooplankton All consumers and producers to decomposers Moray eel Sponges Coral Reef Bacteria

coral bleaching caused by the loss of algae

Ocean warming Soil erosion Algae growth from fertilizer runoff Mangrove destruction Coral reef bleaching Rising sea levels Increased UV exposure from ozone depletion Using cyanide and dynamite to harvest coral reef fish Coral removal for building material, aquariums, and jewelry Damage from anchors, ships, and tourist divers

Biological Zones in the Open Sea: Light Rules Euphotic zone: brightly lit surface layer. Nutrient levels low, dissolved O2 high, photosynthetic activity. Bathyal zone: dimly lit middle layer. No photosynthetic activity, zooplankton and fish live there and migrate to euphotic zone to feed at night. Abyssal zone: dark bottom layer. Very cold, little dissolved O2.

The Coastal Zone High tide Coastal Zone Open Sea Sun Low tide Sea level Photosynthesis Euphotic Zone Estuarine Zone Continental shelf Bathyal Zone Twilight The Coastal Zone Abyssal Zone Figure 6.5 Natural capital: major life zones in an ocean (not drawn to scale). Actual depths of zones may vary. Darkness Fig. 6-5, p. 130

Effects of Human Activities on Marine Systems: Red Alert Human activities are destroying or degrading many ecological and economic services provided by the world’s coastal areas.

Freshwater Life Zones Salt concentration of less than 1% Standing bodies (lakes, ponds, inland wetlands) Flowing bodies (streams and rivers)

Natural Capital Natural Capital Freshwater Systems Ecological Services Economic Services Climate moderation Nutrient cycling Waste treatment Flood control Groundwater recharge Habitats for many species Genetic resources and biodiversity Scientific information Food Drinking water Irrigation water Hydroelectricity Transportation corridors Recreation Employment Figure 6.14 Natural capital: major ecological and economic services provided by freshwater systems. QUESTION: Which two ecological services and which two economic services do you think are the most important?

Lakes: Water-Filled Depressions Lakes: large natural bodies of standing freshwater formed from precipitation, runoff, and groundwater seepage

Life Zones Found in Freshwater Littoral zone – consists of shallow water near the shore to the depth at which rooted plants quit growing. Limnetic zone – the open sunlit water surface away from the shore. The main photosynthetic body of the lake. Profundal zone – deep, open water, too dark for photosynthesis. Benthic zone – at the bottom of the lake. Cool temperatures and low oxygen levels.

Littoral zone Limnetic zone Profundal zone Benthic zone Sunlight Painted turtle Green frog Blue-winged teal Muskrat Pond snail Littoral zone Limnetic zone Diving beetle Profundal zone Plankton Benthic zone Bloodworms Yellow perch Northern pike

Lakes: Water-Filled Depressions During summer and winter in deep temperate zone lakes the become stratified into temperature layers and will overturn. This equalizes the temperature at all depths. Oxygen is brought from the surface to the lake bottom and nutrients from the bottom are brought to the top.

Dissolved O2 concentration 22˚ 4˚ Epilimnion 20˚ 4˚ 18˚ 4˚ 8˚ 4˚ 6˚ 4˚ Hypolimnion Seasonal Changes in Temperate Lakes 5˚ 4˚C 4˚C Thermocline Summer Fall overturn 0˚ 4˚ 2˚ 4˚ 4˚ 4˚ 4˚ 4˚ 4˚ 4˚ 4˚C 4˚C Winter Spring overturn Dissolved O2 concentration High Medium Low

Effects of Plant Nutrients on Lakes: Too Much of a Good Thing Plant nutrients from a lake’s environment affect the types and numbers of organisms it can support. Oligotrophic (poorly nourished) lake: Usually newly formed lake with small supply of plant nutrient input. Eutrophic (well nourished) lake: Over time, sediment, organic material, and inorganic nutrients wash into lakes causing excessive plant growth.

Effects of Plant Nutrients on Lakes: Too Much of a Good Thing Cultural eutrophication: Human inputs of nutrients from the atmosphere and urban and agricultural areas can accelerate the eutrophication process.

Oligotrophic lake Eutrophic lake Sunlight Narrow littoral zone Little shore vegetation Oligotrophic lake Low concentration of nutrients and plankton Limnetic zone deeply sloping shorelines Sparse fish population Profundal zone oligo = little + trophic = nutrition Sand, gravel, rock bottom Sunlight Much shore vegetation Wide littoral zone Eutrophic lake High concentration of nutrients and plankton Limnetic zone Gently sloping shorelines Dense fish population eu = truly + trophic = nutrition Profundal zone Silt, sand, clay bottom

Water flows downhill Surface water Runoff Watershed Drainage basin River basin

Major Characteristics of Freshwater Streams and Rivers Lake Glacier Rapids Rain and snow Waterfall Tributary Flood plain Oxbow lake Salt marsh Ocean Delta Deposited sediment Source Zone Transition Zone Water Sediment Floodplain Zone

Inland Wetlands Land covered with water all or part of the time Marshes Swamps Prairie potholes Floodplains Bogs and fens Wet arctic tundra

Freshwater Inland Wetlands: Vital Sponges Inland wetlands act like natural sponges that absorb and store excess water from storms and provide a variety of wildlife habitats.

Freshwater Inland Wetlands: Vital Sponges Filter and degrade pollutants. Reduce flooding and erosion by absorbing slowly releasing overflows. Help replenish stream flows during dry periods. Help recharge ground aquifers. Provide economic resources and recreation.

Impact of human activities Fragmentation by dams, diversions, or canals Flood control levees and dikes Alter or destroy aquatic habitats Disconnect rivers and floodplains Eliminate wetlands Draining or filling of wetlands Cities and farmlands add pollutants and excess plant nutrients to streams and rivers.

Remember Everything is Connected