()Chesapeake Bay Webquest:
Name: Date: Period:
Directions:
All links can be found through the website, via navigation, at:
www.chesapeakebay.net
Facts & Figures:
http://www.chesapeakebay.net/factsandfigures.aspx?menuitem=14582
What is an estuary:
An estuary is a partially enclosed body of water where fresh water from rivers and streams mixes with salt water from the ocean. Estuaries are areas of transition between the land and the sea. They are often called bays, harbors, inlets or sounds.
What are the dimensions of the bay:
Length of the bay: Bay itself is about 200 miles long, stretching from Havre de Grace, Maryland, to Virginia Beach, Virginia
Width Range: 4 mi to 30 mi
Volume: 800 trillion gallons
Depth Range: 21 ft to 174 ft
Average Depth: 21 ft
How many miles of shoreline make up the bay; 11,684 miles of shoreline
What is the total surface area of the bay: 4,480 square miles
Watershed:
http://www.chesapeakebay.net/thebaywatershed.aspx?menuitem=13942
What is a watershed:
A watershed is an area of land that drains into a particular river, lake, bay or other body of water
What is the land to water ratio and how many tributaries contribute to the Chesapeake Bay? How does this affect the bay?
Chesapeake Bay’s land-to-water ratio is 14:1
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The Chesapeake Bay watershed has 150 major rivers and streams, but contains more than 100,000 smaller tributaries
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The Susquehanna River
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The James River
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The Potomac River
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These Rivers contribute more than 80% of the freshwater to the bay
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Bay Geology:
http://www.chesapeakebay.net/baygeology.aspx?menuitem=14604
What was the initial event that lead to the Bay’s creation:
About 35 million years ago, a rare bolide – a comet- or asteroid-like object from space – hit the area that is now the lower tip of the Delmarva Peninsula, near Cape Charles, Virginia. The bolide created what geologists call the “Exmore Crater,” which they believe was as large as Rhode Island and as deep as the Grand Canyon.
Although this bolide did not create the Chesapeake Bay, it helped determine that a bay would eventually be located there
What other factor contributed to its formation:
During the last Ice Age, mile-thick glaciers stretched as far south as Pennsylvania, and the Atlantic coastline was about 180 miles farther east than it is today.
Approximately 18,000 years ago, the glaciers began to melt, carving streams and rivers that flowed toward the coast. Sea level continued to rise, eventually submerging the area now known as the Susquehanna River Valley. This drowned river valley became the Chesapeake Bay
What three geological areas contribute geology of the bay? What specific characteristics do they add:
Atlantic Coastal Plain
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The coastal plain is supported by a bed of crystalline rock covered with southeasterly dipping wedge-shaped layers of sand, clay and gravel. Water passing through this loosely compacted mixture dissolves many of the minerals. The most soluble elements are iron, calcium and magnesium.
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Piedmont Plateau
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Several types of dense crystalline rock, including slates, schists, marble and granite compose the eastern side of the ridge. This variety creates a very diverse topography. Water from the eastern side of the Piedmont is low in calcium and magnesium salts. The western side of the Piedmont consists of sandstones, shale and siltstones layered over by limestone. this limestone bedrock contributes calcium and magnesium, making the water “hard”. Water from the western side of the ridge flows into the Potomac River.
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Appalachian Provence
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These areas are characterized by mountains and valleys, and they are rich in coal and natural gas. Sandstone, siltstone, shale and limestone form the bedrock.
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The Estuary System:
http://www.chesapeakebay.net/estuarysystem.aspx?menuitem=14605
What three rivers contribute 80% of the Bay’s freshwater:
The Potomac River, the Susquehanna River and the James River
Describe how the salinity of the Bay changes as you travel from the North to the South? Why does this occur?
In general, the lower Chesapeake Bay is salty and the upper Bay is fresh. Salinity decreases as you move north towards the river inlets that provide fresh water to the Bay and increases as you move south closer the ocean which provides the salt water to the Bay.
Chemical Make-Up:
http://www.chesapeakebay.net/discover/bayecosystem/chemicalmakeup
Why does the chemical composition of freshwater vary place to place:
The composition of fresh water varies depending upon the soil and rocks the water has come into contact with.
What are the three sources that contribute to the chemical composition of fresh & salt water:
Bacteria and other microorganisms decompose dead organisms and release compounds into the water. Live organisms also release compounds directly into the water. Additionally, dissolved materials enter the Bay from its rivers and the ocean.
What two gases are most important for organisms in the Bay:
oxygen and carbon dioxide
http://www.chesapeakebay.net/issues/issue/nutrients
Nitrogen and Phosphorus are important nutrients for Bay organisms. How and why are they causing so many problems in the Bay:
When nitrogen and phosphorus enter rivers, streams and the Bay, they fuel the growth of algae blooms that lead to low-oxygen “dead zones” that are harmful to fish, shellfish and other aquatic life.
Food Web:
http://www.chesapeakebay.net/discover/bayecosystem/foodwebs
In the space below, create a simplified version of the food web that is presented. In your diagram, label and describe the roles of each organism:
Describe how the chemical contaminants move through the food web?
Small bottom-dwelling organisms take up contaminants that are in the bottom sediments while feeding or through skin contact.
Larger fish accumulate toxins in their tissues when they eat contaminated smaller organisms.
In turn, birds, other wildlife and even humans may eat contaminated fish allowing the contaminants to continue to move through the food chain.
Fish of the Bay:
http://www.dnr.state.md.us/fisheries/fishfacts/index.asp
Draw two of any of the fish and one of the shellfish presented on this page. Describe their defining characteristics (click on their picture for this information):
Atlantic Croaker
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Chin with 3-5 pairs of small barbells and 5 pores.
Caudal fin double concave.
Body is elongate and somewhat compressed.
Dorsal fin deeply notched, with 10 spines in the anterior portion and 1 spine and 26-30 soft rays in the posterior portion.
Upper dorsal side with numerous brassy spots that from wavy bars (less distinct in large individuals).
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Monkfish
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The species is easily recognized because of its large spiny head and wide mouth filled with fang-like teeth.
Monkfish have very broad, depressed heads (head is as wide as the fish is long)
They have enormous mouths with long, sharp teeth.
Monkfish have a modified spine called an "esca."
This spine is quite mobile and can be angled forward so it can dangle in front of the fish's mouth and be wiggled like bait to lure its prey.
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Horseshoe Crab
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These animals get their name from their general horseshoe shape.
They have a hard exoskeleton like a crab.
They are brown with a slender pointed tail.
A horseshoe crab's tail, while menacing, is not a weapon. Instead, the tail is used to plow the crab through the sand and muck, to act as a rudder, and to right the crab when it accidentally tips over.
Unique looking, with nothing else that looks much like them in existence today.
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Crabs & Shellfish:
http://www.chesapeakebay.net/crabsandshellfish.aspx?menuitem=14623
What are the two broad categories that encompass crabs and shellfish? What are their defining characteristics and examples:
anthropods
Arthropods have an external skeleton—or exoskeleton—that they molt to grow. Crustaceans like crabs, shrimp and barnacles are the Bay's most common arthropods. Horseshoe crabs are arthropods, but not crustaceans: they are more closely related to spiders and scorpions
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Mollusks
Mollusks include bivalves, gastropods (snails) and cephalopods (squid). Most mollusks have at least one shell that protects and supports the animal’s soft body. They also have a foot, which allows them to move.
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Bay Grasses:
http://www.chesapeakebay.net/baygrasses.aspx?menuitem=14621
What are three of the roles of bay grasses that help other organisms:
Underwater grasses provide food, oxygen and habitats for other organisms
What four things do bay grasses do to help to keep the bay clean:
Bay grasses absorb nutrient pollution, trap sediment, reduce erosion and add oxygen to the water
Bay Habitats:
http://www.chesapeakebay.net/blog/post/what_habitats_are_found_in_the_chesapeake_bay_watershed
Using links, provide a quick description of each habitat:
Forests
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Forests now only cover about 58% of the watershed. Forests provide vital habitats for wildlife, filter pollution keeping the waterway cleaner and act as natural sponges that absorb runoff.
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Wetlands
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Wetlands are transitional areas between land and water. There are two categories, tidal and non-tidal. Tidal wetlands, found along the Bay’s shores, are filled with salt or brackish water. Non-tidal wetlands contain fresh water.
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Streams & Rivers
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Streams and rivers provide the bay with fresh water as well as providing many aquatic species with critical habitats.
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Shallow Waters
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Shallow waters are the areas of water from the shoreline to about 10 ft. deep. Shallow waters are constantly changing with the tides and weather throughout the year. The shallows support plant life, fish, birds and shellfish.
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Tidal Marshes
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Tidal marshes in the Bay’s shallows connect shorelines to forests and wetlands. Marshes provide food and shelter for the wildlife that lives in the Bay’s shallow waters. Freshwater marshes are found in the upper bay, brackish marshes in the middle Bay and salt marshes in the lower Bay
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Aquatic Reefs
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Aquatic reefs are solid three-dimensional habitats made up of densely packed oysters. the reefs form when oyster larvae attach to larger oysters at the bottom of the bay
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Open Waters
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Open waters are beyond the shoreline and the shallows. Aquatic reefs replace underwater bay grasses, which cannot grow where sunlight cannot penetrate deep waters. Open water provides vital habitat for pelagic fish, birds and invertebrates
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Bay Pressures:
http://www.chesapeakebay.net/baypressures.aspx?menuitem=13959
Using links, give a quick description of how each of the following puts pressure on the Bay:
Land & People:
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The increase in human population has reduced the amount of land available for native species and has reduced the sustainability of the plants and animals that live in the Bay. Wastewater from sewage treatment plants also increase nutrients into the bay and its tributaries, contributing to algal bloom.
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Air & Water Pollution:
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Air pollution from cars, trucks and other burning of fossil fuels pollutes the bay when the harmful gases are absorbed by the waters. Chemical contaminants, such as pesticides, pharmaceuticals, metals, household cleaners all harm the ecosystem of the Bay by killing off species.
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Fisheries Harvest:
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Commercial fisheries have overharvested many of the once populous species, such as oysters and shad, two vital organisms to the Chesapeake Bay, endangering the balance of the ecosystem.
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Natural Factors:
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Storms can upset the balance of the ecosystem as habitats are altered from erosion and flooding. Diseases, such as viruses, and reduce populations of vital species, such as the oysters.
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Invasive Species
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Invasive species can cause harem when they establish themselves at the expense of native plants and animals, using up resources.
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Climate Changes:
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Climate change has been lined to rising seas, warming water temperature and prolonged periods of extreme weather. More immediate effects include a rise in coastal flooding, shoreline erosion and changes in wildlife abundance and migration patterns.
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Bay Restoration:
http://www.chesapeakebay.net/takeaction/howtotips
Using the links, describe how each of the following helps the bay:
Restoring Water Quality
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By reducing graywater by using biodegradable soaps, using toxic-free paints, reducing runoff, and conserving water, the water that flows into the bay is cleaner, restoring water quality
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Habitat Restoration
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By using fertilizers properly, reducing, recycling and reusing, by planting plants to prevent erosion, and by composting, the pressures on the habitats can be reduced, allowing them to return to their natural balance.
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Managing Fisheries
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By limiting or restricting the numbers of catch and the time of catch, fish can have a chance to regain the optimal population for the health of the bay.
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Protecting Watersheds
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Because watershed feed directly into the Bay, human actions in the watershed areas have a direct effect on the Bay’s health.
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