Moving to the Oceans –Estuaries 15

8th Grade Science

Copy items in red and images indicated.

EstuariesEstuary: is a body of water, partially enclosed by land, where fresh water from a river mixes with salt water from the ocean.

Water in Estuaries is Brackish. Brackish means partly fresh and partly salty.

Coastal Ocean

Estuary

River

Draw picture

Schematic of a typical Estuary

ESTUARY IMAGES

Neuse River Estuary

Neuse River

Very Fresh

VerySalty

Neuse River Basin

Neuse River

NC largest Estuary is the Pamilco Sound

What does an estuary look like from a satellite vs a helicopter?

Ocean

Brackish

Fresh

Protective Environment

• Estuaries help control erosion & reduce flooding. • 1. Sand bars buffer impact of waves • 2.Plants and shell fish beds anchor the shore against

tides. • Swamps and marshes take the initial impact of high

winds moving in from the ocean, soak up heavy rain and storm surges, and release the extra the extra water gradually into river and groundwater supplies.

Protective Environment

1. Because estuaries are shallow (less than 30 ft deep) sunlight penetrates all the way to the bottom. This promotes plant growth.

2. Rivers feed estuaries sediments rich in nutrients, which settle onto the sand and mud of the estuary floor. These unique conditions create biodiversity in species of (fish, shrimp, crabs, clams, and oysters) that adapt the brackish conditions.

Estuaries are great Nurseries!

• Estuaries are also good nurseries as they provide a protected environment for species to hatch and grow in before they migrate to the sea to live out their adult lives.

Nurseries

• Estuaries act as “Nurseries” for marine and aquatic species.– Marine – Live in ocean– Aquatic – Live in water

• Fish will lay eggs in estuaries– Safe from ocean

predators– Calmer, more nutrient rich water

Resting and Breeding Ground

• Birds depend on the estuary for resting and feeding

• Lots to eat

• Crabs, worms, clams, and more live in the muddy areas.

Filtering System

• Estuaries clean our rivers by removing…..

Sediment and Pollutant.

This makes me think of…______

Sediments• Sediment – Soil particles and chemicals carried

by the river• Carrying of soil Muddy estuaries– Soil can smother fish eggs, aquatic insects, and

plants with mud.

• Erosion of land Chemical deposits– Chemicals can kill life

• Some estuaries are actually salt marshes.– These plants and

mud take up some of the sediments and pollutants!

• Animation of salt marsh

• Salt Marsh Filtering

• http://oceanservice.noaa.gov/education/kits/estuaries/media/supp_estuar03a_marsh.html

Pollutants

• Pollutants: Pesticides, sewage and industrial waste

• Estuaries are a type of environmental filter.

• Plants and animals in estuaries filter pollutants out of the water.

Pollutants

• Ex: Salt Marsh Plants trap some of the chemicals and pathogens carried by rivers and move them into soils where they can be neutralized.

• Ex: Oysters filter impurities out of the water as they eat, collecting contaminants in their bodies. One oyster can filter 25 gallons of water per day

• Too many toxins can accumulate in estuaries causing many environmental and health problems

What does an estuary look like from a satellite vs a helicopter?

Ocean

Brackish

Fresh

Protective Environment

• Estuaries help control erosion & reduce flooding. • 1. Sand bars buffer impact of waves • 2.Plants and shell fish beds anchor the shore against

tides. • Swamps and marshes take the initial impact of high

winds moving in from the ocean, soak up heavy rain and storm surges, and release the extra the extra water gradually into river and groundwater supplies.

Protective Environment

1. Because estuaries are shallow (less than 30 ft deep) sunlight penetrates all the way to the bottom. This promotes plant growth.

2. Rivers feed estuaries sediments rich in nutrients, which settle onto the sand and mud of the estuary floor. These unique conditions create biodiversity in species of (fish, shrimp, crabs, clams, and oysters) that adapt the brackish conditions.

Estuaries are great Nurseries!

• Estuaries are also good nurseries as they provide a protected environment for species to hatch and grow in before they migrate to the sea to live out their adult lives.

Nurseries

• Estuaries act as “Nurseries” for marine and aquatic species.– Marine – Live in ocean– Aquatic – Live in water

• Fish will lay eggs in estuaries– Safe from ocean

predators– Calmer, more nutrient rich water

Wetlands 16

• What is a wetland?– An area where the water table is at, near or above

the land surface long enough during the year to support adapted plant growth

• What are the types of wetlands?– Swamps, bogs, and marshes• Swamp: a wetland dominated by trees• Bogs: a wetland dominated by peat moss• Marshes: a wetland dominated by grasses

Wetlands 16Why are they important?

1. Help prevent Flooding by absorbing excess water

2. Help prevent erosion3. Help filter water flowing through it

Discovery Education Video

• Water sheds and Wetlands of North America – Time 1:23

• Ecosystems (Watersheds, Estuaries and Wetlands) (Time 2:25)

• Goto www.DiscoveryEducation.comOpen in BrowerU: lgrovestudentP: 8science Click on “Assignments”

Work Cited

• http://estuaries.noaa.gov/Teachers/estuaries.aspx

• http://oceanservice.noaa.gov/education/kits/estuaries/media/supp_estuar03a_marsh.html