Aquatic Biomes Water on the Earth 75 78

Aquatic Biomes

Water on the Earth Ø 75% - 78% of the Earth’s surface is covered in water

How much freshwater? Of all the water available on Earth… Ø Only 3% is freshwater Ø Of the 3% freshwater, 2% is tied up in glaciers and icebergs… Ø Only leaving less than 1% available to humans. Ø

Types of Life in An Aquatic Biome

What factors influence the kind of life an aquatic biome contains? Ø Salinity Ø Depth (Sunlight) Ø Speed of water flow Ø Dissolved oxygen levels

Major types of aquatic biomes Ø Salt Water l l l Estuaries** Coastlines Coral Reefs Coastal Marshes** Mangrove Swamps** Oceans ** May be brackish Ø Fresh Water l l l Streams Rivers Lakes Ponds Wetlands (inland)

Limnology The study of fresh water and its ecosystems The study of freshwater ecosystems can be divided into 2 systems 1. Lentic – standing water (little or no current) 2. Lotic – flowing water

Examples of Lentic Systems Ø Standing water l l l Lakes Ponds Wetlands • • • Marshes Swamps bogs

Lakes Ø Oligotrophic: poorly nourished Ø Eutrophic: richly nourished

Examples of Lotic Systems Ø Moving water l l Rivers Streams

Life Found in Aquatic Systems

Phytoplankton “Plant Plankton” Ø Free Floating Ø Microscopic Ø Cynobacteria or algae Ø Producers Ø Contain cholorphyll photosynthetic Ø Support most aquatic food chains and food webs Ø

Did you know? ? • Plants in the ocean produce over half the world's oxygen. • The most important plants in the ocean are too small to be seen without a microscope. • They float near the surface and drift with the currents, so they have been named phytoplankton (phyto=plant, plankton=drifter). • Phytoplankton are the 'grass' of the sea. Where they grow there is food for marine animals. • Ocean color tells you how much phytoplankton there is in the water.

Zooplankton “Animal Plankton” Ø Non-photosynthetic Ø Consumers (herbivores) Ø l Feed on phytoplankton Single Celled Protozoa to larger invertebrates such as jellyfish Ø Many zooplankton are larval stages of familiar animals Ø

Strong Swimmers Consumers Fish, turtles, Whales Nekton

Ø Bottom Dwellers l l l Ø Benthos Anchor to one spot: barnacles, oysters Burrow in mud or sand: worms Walk on bottom: Lobsters, crabs Habitats: l l Intertidal zones, rocky shores, tide pools Muddy Sandy communities Deep ocean/ coral reefs Hydrothermal vent areas • archaebacteria

Decomposers Break down organic compounds into simple nutrients that can be used by producers Ø Break down dead bodies and waste Ø

Characteristics of an Aquatic Biome

Ø Have less pronounced and fixed physical boundaries l l Makes it difficult to count and manage populations due to the size of the ocean and many organisms are largely hidden from view

Catch and release Acoustics used to measure Krill Populations Tagging with electronic monitors

Characteristics of an Aquatic Biome Ø Have more complex and longer food chains and food webs

Ocean Biomes

Euphotic Zone Photosynthesis Sun Twilight Estuarine Zone Continental shelf Open Sea level Bathyal Zone Abyssal Zone Darkness High tide Coastal Zone Low tide Fig. 6 -5, p. 130

Biological Zones in the Open Sea: Light Rules Ø Euphotic zone: brightly lit surface layer. l Nutrient levels low, dissolved O 2 high, photosynthetic activity. Ø Bathyal zone: dimly lit middle layer. l No photosynthetic activity, zooplankton and fish live there and migrate to euphotic zone to feed at night. Ø Abyssal zone: dark bottom layer. l Very cold, little dissolved O 2.

Advantages of living in the ocean

Physical support from water buoyancy Organisms take advantage of water's buoyancy to transport themselves to nearby or distant habitats with little energy expenditure

Fairly constant temperature

Nourishment from dissolved nutrients

Areas of pronounced upwelling -Deep oceanic currents colliding with sharp coastal shelves -Temperature differences / changes -Surface Winds

Water Availability Ø Oceans cover 139, 400, 000 square miles of the Earth’s surface Ø The average depth of the oceans is 12, 238 feet

Easy dispersement of organisms, larvae and eggs Water propulsion

Hydrofoils - use of flippers Up/Down movement of pectoral fins

Ø A big difference between fish and dolphins is that a fish's tail moves from side to side and a dolphin's moves up and down.

The more slender the body shape, the faster the movement

Advantages Ø Less exposure to harmful radiation Ø Dilution and dispersion of pollutants

Disadvantages Ø Can tolerate a narrow range of temperatures Ø Exposure to dissolved pollutants Ø Fluctuating populations size for many species Ø Dispersion separates many aquatic offspring from parents

Why are oceans important? Ø Covers 71 -75% of earth’s surface Ø Make up 99. 5% of earth’s habitable volume Ø Contain 250, 000 known species of plant and animals Ø Provide important and ecological and economic services

Ecological Services

Ecological Services Ø Climate moderation Ø Carbon dioxide absorption Ø Nutrient cycling Ø Reduced storm impact (mangrove swamps, estuaries, barrier islands) Ø Habitats and nurseries for species (shrimp, crab, oysters, clams, fish) Ø Genetic resources and biodiversity

Mangrove Swamps (Forest) Ø Mangrove swamps are found along tropical seacoasts on both sides of the equator

Estuaries

Barrier Islands

Economic Services

Food

Pharmaceuticals Algae: Astaxanthin is a powerful natural antioxidant / dietary supplement

Transportation Ø Ocean transport is the backbone of internal trade

Coastal Habitats and Employment for Humans

Recreation

Offshore Oil and Natural Gas / Minerals

Coastal Zones

What is a coastal zone? Ø The coastal zone is the warm, nutrient rich, shallow water from high tide area on land to the edge of the continental shelf. l l Contains 90% of all marine species Site of most commercial fisheries Ø Ample supply of sunlight and nutrients

Estuaries / Coastal Wetlands Ø Part of coastal zone Ø Brackish (mixture of salt and freshwater) l l Usually due to the movement of the tides Salinity and temperature vary due to • Daily tides • Seasonal variations and its affect of water flow • Unpredictable flows of water from flooding or storms Ø Constant movement of nutrients due to flow of water

Estuaries / Coastal Wetlands Ø Covered with water all or part of the year l l l River mouths (delta’s) Inlets Bays Sounds Mangrove forest swamps Salt marshes

Major life zones in an ocean

Continental Rise

Oceans