Watersheds
What is a Watershed
A watershed is the land that flows across, under, or through it’s way to a stream, River, lake, wetland or any other body of water.
WHY ARE ESTUARIES IMPORTANT?
PEOPLE DEPEND ON ESTUARIES FOR TRADE, FOOD, AND SHELTER
FROM VIOLENT OPEN OCEAN WATER. AMONG OTHER BENEFITS,
ESTUARIES PROVIDE RECREATION IN THE FORM OF SWIMMING,
BOATING, FISHING, SURFING, AND BIRD WATCHING.
•ESTUARIES ACT AS A NATURAL LABORATORY FOR SCIENTISTS AND
STUDENTS. THE ECONOMY OF MANY COASTAL COMMUNITIES IS
DIRECTLY LINKED TO THE AESTHETIC BEAUTY OF THE ESTUARY
NEARBY
WHAT ARE BIOTIC AND ABIOTIC FACTORS IN AN ECOSYSTEM?
•AN ECOSYSTEM IS MADE UP OF THE LIVING COMMUNITY AND THE
NONLIVING FACTORS THAT AFFECT THE ORGANISMS LIVING IN IT.
• THE NONLIVING, PHYSICAL FEATURES OF THE ENVIRONMENT ARE THE
ABIOTIC FACTORS, WHICH DETERMINE ECOSYSTEM TYPE AND ITS
DISTRIBUTION OF PLANTS AND ANIMALS. ABIOTIC FACTORS INCLUDE
WATER QUALITY, TOPOGRAPHY, LANDFORMS, GEOLOGY, CLIMATE,
SOIL TYPES, AMOUNT OF SUNLIGHT, AND AIR QUALITY OR OXYGEN
AVAILABILITY.
•BIOTIC FACTORS ARE ALL THE LIVING ORGANISMS IN AN ECOSYSTEM.
THIS INCLUDES ALL THE PEOPLE, ANIMALS, AND PLANTS.
• THE HEALTH OF AN ECOSYSTEM IS DIRECTLY RELATED TO ITS WATER
QUALITY
What are Virginia Watershed
-The Virginia Department of Game and Inalnd fisheries defines 12 major watersheds in Virginia.
- The 3 major reiganol watershed system in Virginia lead to the Cheasepeke Bay, The North Carolina Sounds, and the Gulf of Mexico
HEALTH OF THE ESTUARY
LIKE OUR RIVERS AND STREAMS, ESTUARIES ARE IN DANGER AS A
RESULT OF HUMAN ACTIVITY. MUCH TRASH AND SEDIMENT FROM
UPRIVER ARE CARRIED INTO THE ESTUARY. CHEMICAL
CONTAMINATION IN AN ESTUARY CAN LINGER FOR YEARS AND CLOSE
DOWN FISHING IN THOSE AREAS. SILT AND OTHER SEDIMENT CAUSED
BY EROSION CAN SUFFOCATE BOTTOM-DWELLING PLANTS AND
ANIMALS. NUTRIENTS FROM UPSTREAM MAKE THEIR WAY INTO THE
ESTUARY AND CAUSE OVER-ENRICHMENT OF THE WATER AND
OXYGEN DEPLETION.
HOW DO HUMANS AFFECT WATER QUALITY?
• HUMAN ACTIVITY CAN ALTER ABIOTIC FACTORS AND THUS ACCELERATE OR
DECELERATE NATURAL PROCESSES.
• HUMAN ACTIVITY CAN AFFECT WATER QUALITY IN TWO WAYS: BY
CHANGING THE ECOLOGICAL PROCESSES THAT NATURALLY PURIFY
WATER, AND BY ADDING POLLUTANTS.
• FOR EXAMPLE, PEOPLE CAN AFFECT THE RATE OF NATURAL EROSION ONE
WAY OR THE OTHER. PLOWING CROPLAND CAN CAUSE GREATER EROSION,
WHILE PLANTING TREES CAN LESSEN IT.
• PRESERVING OR DESTROYING WETLANDS IS ANOTHER EXAMPLE, BECAUSE
WETLANDS REGULATE RUNOFF, REDUCE EROSION, PURIFY WATER BY
FILTERING IT, AND RECHARGE GROUNDWATER.
WHAT ARE RIVERS, STREAMS, TRIBUTARIES, AND
FLOOD PLAINS?
WHAT ARE RIVERS, STREAMS, TRIBUTARIES, AND
FLOOD PLAINS?
•Rivers and streams are bodies of moving water that flow in one
direction.
•Rivers come in all shapes and sizes, but they all have some things
in common. All rivers and streams start at some high point. The
high point can be a mountain, hill, or other elevated area.
•River systems are made up of tributaries of smaller streams that
join along their courses.
•Rivers and streams generally have wide, flat, border areas called
Flood Plains, onto which water spills out at times of high flow.
SWAMPS
SWAMPS ARE WETLANDS WHERE THE MOST
COMMON PLANT TYPES ARE TREES (CYPRESSES,
WILLOWS, OAKS), VINES (POISON IVY), AND SHRUBS.
THEY OCCUR IN LOW-LYING AREAS NEAR
SLOW-MOVING RIVERS AND NEED A STEADY
SUPPLY OF WATER IN ORDER FOR TREES TO GROW.
WHAT ARE NON-POINT SOURCE POLLUTANTS?
LAND-USE CHANGES UPSTREAM CAN CAUSE RUNOFF POLLUTION PROBLEMS FOR
PEOPLE, PLANTS, AND ANIMALS DOWNSTREAM THAT DEPEND ON CLEAN, USABLE
WATER.
• THIS FORM OF POLLUTION IS CALLED NON-POINT-SOURCE POLLUTION (NPS), BECAUSE
THE POLLUTION DOES NOT COME FROM A SINGLE SOURCE, SUCH AS THE DISCHARGE
FROM A SEWAGE TREATMENT PLANT OR A FACTORY.
• NPS POLLUTION IS CAUSED MAINLY BY STORM-WATER RUNOFF.
• FOR EXAMPLE: WHEN IT RAINS HARD, WATER RUNS OFF FARMLAND, CITY STREETS,
CONSTRUCTION SITES, LAWNS, AND DRIVEWAYS, CARRYING SEDIMENT, NUTRIENTS,
PESTICIDES, OIL AND GASOLINE, BACTERIA, AND OTHER POLLUTANTS WITH IT.
• ONE OF WATER’S UNIQUE PROPERTIES IS ITS ABILITY TO DISSOLVE A WIDE VARIETY OF
COMPOUNDS. THUS, WATER-SOLUBLE MATERIALS EASILY POLLUTE WATER, WHICH
THEN CARRIES THESE HARMFUL SUBSTANCES INTO OUR WATERWAYS AND OTHER
BODIES OF WATER.
WHAT ARE ESTUARIES?
ESTUARIES ARE PARTIALLY ENCLOSED BODIES OF WATER WHERE FRESHWATER
FROM STREAMS AND RIVERS MEETS SALTY OCEAN WATER. BAYS, LAGOONS,
HARBORS, INLETS, AND SOUNDS ARE EXAMPLES OF ESTUARIES.
• ESTUARIES PERFORM IMPORTANT FUNCTIONS, SUCH AS PROVIDING HABITAT FOR
MANY ORGANISMS AND SERVING AS NURSERIES FOR THEIR YOUNG.
• THE CHESAPEAKE BAY IS AN ESTUARY WHERE FRESH AND SALT WATER MEET
AND ARE MIXED BY TIDES. IT IS THE LARGEST ESTUARY IN THE CONTIGUOUS
UNITED STATES AND ONE OF THE MOST PRODUCTIVE.
•HOWEVER, THE POPULATION AROUND THE CHESAPEAKE BAY HAS REACHED 15
MILLION PEOPLE AND THE BAY’S NATURAL RESOURCES ARE BEING THREATENED.
MARSHES
MARSHES
•MARSHES ARE TREELESS WETLANDS SOMETIMES
CALLED WET MEADOWS. GRASSES, REEDS,
CATTAILS, AND NONWOODY PLANTS CALLED
RUSHES AND SEDGES ARE COMMON MARSH
PLANTS. MARSHES OFTEN FORM ON FLOODPLAINS
WHERE RIVERS OVERFLOW THEIR BANKS.
What are the 4 primary NPS Pollutants
WHAT ARE THE 4 PRIMARY NPS POLLUTANTS?
• THE FOUR PRIMARY NPS POLLUTANTS ARE SEDIMENT, NUTRIENTS, TOXIC CHEMICALS, AND
DISEASE-CAUSING PATHOGENS.
• SEDIMENT IS SOIL CARRIED BY RAINWATER INTO STREAMS, RIVERS, AND LAKES. IT CUTS LIGHT
NEEDED BY AQUATIC PLANTS, BLOCKS UP WATERWAYS, AND COVERS UP AQUATIC HABITAT.
OFTEN THE SEDIMENT FROM FARMLAND ALSO CARRIES PESTICIDES AND NUTRIENTS.
• TOXIC CHEMICALS, SUCH AS PESTICIDES, HERBICIDES, AND OIL AND GASOLINE, CAN DAMAGE
AND/OR KILL AQUATIC ANIMAL AND PLANT LIFE.
• NUTRIENTS, PARTICULARLY NITROGEN AND PHOSPHORUS, OVER-ENRICH BODIES OF WATER,
CAUSING EXCESSIVE GROWTH OF ALGAE. WHEN ALGAE DIE, BACTERIA DECOMPOSE IT,
DECREASING THE WATER’S DISSOLVED OXYGEN LEVEL IN THE PROCESS. LOW OXYGEN CAN KILL
OR CAUSE DISTRESS TO AQUATIC ANIMALS. ALGAE ALSO CLOUD THE WATER AND BLOCK
MUCH-NEEDED SUNLIGHT.
• PATHOGENS ENTER BODIES OF WATER PRIMARILY THROUGH HUMAN OR ANIMAL WASTE.
ESTUARY AS HABITAT
A VERY LARGE NUMBER OF FISH THAT ARE USED COMMERCIALLY
RETURN FROM THE OCEAN TO SPAWN IN THE PROTECTIVE WATERS
OF ESTUARIES.
•SEVENTY-FIVE PERCENT OF COMMERCIAL FISH CATCH AND 80
PERCENT OF RECREATIONAL FISH CATCH MAKE THEIR HOME IN
ESTUARIES.
•OYSTERS, CLAMS, AND CRABS THRIVE IN THE BAYS AND INLETS.
•ESTUARIES PROVIDE A HABITAT FOR ENDANGERED AND
THREATENED BIRDS.
Bogs
•BOGS ARE CHARACTERIZED BY LOW TO MEDIUM-HEIGHT WOODY
PLANTS. THE ONLY SOURCE OF FRESHWATER IN A BOG IS RAIN.
•SINCE NO STREAMS CARRYING NUTRIENTS FLOW INTO BOGS,
PLANTS, SUCH AS THE VENUS FLYTRAP, GET NUTRIENTS FROM
INSECTS.
•BECAUSE WATER DOES NOT DRAIN FROM A BOG, DEAD PLANT
MATERIAL BUILDS UP AND SINKS TO THE BOTTOM.
•EVENTUALLY A SUBSTANCE CALLED PEAT IS FORMED.
GARDENERS USE PEAT FROM A PLANT CALLED SPHAGNUM MOSS,
WHICH, WHEN DRIED, CAN HOLD UP TO 20 TIMES ITS WEIGHT IN
WATER