BESC Exam 3 Questions with correct
Answers
Freshwater - Answer -Water that is relatively pure and which contains few dissolved
salts. Freshwater accounts for only 2.5% of water on Earth; of that 1% is surface
freshwater.
Aquifer - Answer -An underground water reservoir. A porous, sponge-like formation of
rock, sand, or gravel that holds water. This water is usually held in pore spaces of soil
and rock within the aquifer, not as a massive underground lake.
Groundwater - Answer -Water that is held in aquifers underground
Water Table - Answer -The boundary between zone of aeration and saturation.
Zone of Aeration - Answer -The upper area within aquifers where pore spaces are
partially filled by water.
Zone of Saturation - Answer -The lower area within an aquifer where the pore spaces
are completely filled with water.
Recharge Zone - Answer -The above ground land area that allows surface water to
infiltrate into the aquifer below, thus recharging the aquifer.
Watershed - Answer -An area of land where all the water that is in it, or falls within it,
drains off into a singular outlet through a network of rivers and streams.
Three types of fresh water systems - Answer -Floodplains, tributaries, and riparian
zones
Floodplains - Answer -Land alongside a river. Floodplains are at the bottom of valleys
and are surrounded by uplands, or lands with higher elevation. When the river floods, it
deposits silt, gravel, and clay onto the floodplain. This action makes the soil of
floodplains very fertile. Consequently floodplains are commonly used for agriculture.
Tributaries - Answer -smaller rivers or streams that flow into the main river.
Riparian - Answer -The land along the banks of a river or stream. Riparian areas are the
transitional areas between the aquatic system of the river and the terrestrial ecosystem
,on land. Riparian areas consist of the vegetation that grows along the banks of the river.
Species rich.
Four types of wetlands - Answer -Freshwater Marshes
Swamps
Bogs
Vernal Pools
Freshwater Marshes - Answer -Usually found at mouths of rivers and have shallow
water and vegetation that grows above the surface of the water, such as cattails and
bulrushes. Large stretches of freshwater marshes span much of the Florida Everglades
Swamps - Answer -Wetlands in forested areas
Bogs - Answer -Ponds covered in thick floating mats of vegetation and may be a
transitional stage of aquatic succession.
Vernal Pools - Answer -Seasonal wetlands that exist only during wet portions of the
year
Wetlands ecosystem services - Answer -Slowing runoff, reducing flooding, recharging
aquifers, and filtering pollutants
Lakes and Ponds are - Answer -Standing water with distinct zones.
Oligotrophic lakes and ponds - Answer -have low nutrient content and high oxygen
conditions. These lakes look clear and are support a variety of organisms. Oligotrophic
lakes can transform into eutrophic lakes.
Eutrophic lakes and ponds - Answer -lakes with high nutrient and low oxygen
conditions. The process of eutrophication is natural. As some lakes age over centuries,
there is a buildup of nutrients, sediment, and plant material, which slowly fill the lake
basin. Process end s and becomes colonized by terrestrial vegetation.
Littoral Zone - Answer -The nutrient rich edges of the water body, where the water is
shallow enough to allow aquatic plants to grow. This region has a rich diversity of
organisms including aquatic invertebrates such as insects, snails and crawfish, as well
as vertebrates such as birds, fish, turtles and amphibians.
Limnetic Zone - Answer -The open portion of the lake that is shallow enough to allow
sunlight to penetrate its entire depth. The sunlight enables photosynthesis to occur in
this zone, which means this area is teeming with photosynthetic organisms such as
algae, protists, and cyanobacteria.
Profundal Zone - Answer -The region below the limnetic zone. This region of the lake is
the open water of the lake that is too deep to allow light to reach it. The profundal zone
,does not have photosynthetic organisms and thus the dissolved oxygen levels are lower
in this zone compared to the limnetic zone.
Benthic zone - Answer -The portion of a lake that extends along the very bottom, from
the shore to the deepest point of the lake/pond. Invertebrates that live in this zone are
called benthic invertebrates and are often studied to assess the health of the aquatic
system.
Challenge of water - Answer -Unevenly distributed in space and time
Water mining - Answer -When we withdraw water faster than it can be replaced from
either surface water or ground water.
Ogalla Aquifer - Answer -Worlds largest known aquifer, found in the Great plains of the
U.S.
Several consequences of overdrawing an aquifer - Answer -Water tables drop
Wetlands dry up
Water becomes rarer/expensive
If near coast, salt water can intrude
Land will subside(sink)
Soil will become compacted, lose porosity, ultimately making recharge harder
Water use can be characterized as either - Answer -Consumptive or non-consumptive
us
Consumptive water - Answer -An activity that removes water from an aquifer or surface
water body and is not returned. For example, water used for irrigation.
Non-Consumptive - Answer -An activity that either does not remove water or only
temporarily removes water, such as is done with electricity generation at hydroelectric
dams.
A nuclear power plant removes water from a local river to cool the rods used to
generate energy. This water is released into the atmosphere as steam.
What type of water? - Answer -Consumptive
Dam - Answer -any obstruction placed in a river or stream to blow flow of water
Reservoirs - Answer -artificial lakes made by dams.
The largest dam is - Answer -Chinas Three Gorges Dam. 385 mile long reservoir, the
length of lake superior.
Pros and cons of dams/resevoirs - Answer -Pros
, - Irrigation
- Low carbon emissions
- Recreation(resrvoir)
- Renewable Energy
- Drinking Water
- Flood control
Cons
- Displacement of people
- Sediment build up behind dams
- RIsk of failure
- Habitat alteration (up/downstream)
- Soil build up at bottom
- Fisheries decline
- Lost rec activity (dam)
Desalination - Answer -The removal of salt from seawater is another option for creating
more supply. The problem with desalination though is that it is an energy intensive
process and requires a great deal of fossil fuels and electricity.
How can we reduce demand for freshwater? - Answer -Use drip irrigation instead of
flood and furrow or conventional irrigation
Xeriscaping - Answer -landscaping and gardening that reduces or eliminates the need
for irrigation. This is used in the southern U.S. and incorporates drought tolerant and
native species that require little to no supplemented water.
Reclaimed Water - Answer -water that is treated but not to the point that it is potable.
This type of water can be used to irrigate lawns, parks and golf courses and can be
used to flush toilets.
Majority of water is used for _______ - Answer -agriculture
Which of the following is not a consequence of overdrawing an aquifer? - Answer -
Subsidence; the rehydration of wetlands.
Freshwater pollution can come from either - Answer -Point sources or non-point sources
Point source pollution - Answer -direct discharge from a single location
- sewage treatment plants
- disposal sites
- factories
Non-point source pollution - Answer -indirect discharge that comes from multiple sites
over large areas
- lawns
- neighborhoods
Answers
Freshwater - Answer -Water that is relatively pure and which contains few dissolved
salts. Freshwater accounts for only 2.5% of water on Earth; of that 1% is surface
freshwater.
Aquifer - Answer -An underground water reservoir. A porous, sponge-like formation of
rock, sand, or gravel that holds water. This water is usually held in pore spaces of soil
and rock within the aquifer, not as a massive underground lake.
Groundwater - Answer -Water that is held in aquifers underground
Water Table - Answer -The boundary between zone of aeration and saturation.
Zone of Aeration - Answer -The upper area within aquifers where pore spaces are
partially filled by water.
Zone of Saturation - Answer -The lower area within an aquifer where the pore spaces
are completely filled with water.
Recharge Zone - Answer -The above ground land area that allows surface water to
infiltrate into the aquifer below, thus recharging the aquifer.
Watershed - Answer -An area of land where all the water that is in it, or falls within it,
drains off into a singular outlet through a network of rivers and streams.
Three types of fresh water systems - Answer -Floodplains, tributaries, and riparian
zones
Floodplains - Answer -Land alongside a river. Floodplains are at the bottom of valleys
and are surrounded by uplands, or lands with higher elevation. When the river floods, it
deposits silt, gravel, and clay onto the floodplain. This action makes the soil of
floodplains very fertile. Consequently floodplains are commonly used for agriculture.
Tributaries - Answer -smaller rivers or streams that flow into the main river.
Riparian - Answer -The land along the banks of a river or stream. Riparian areas are the
transitional areas between the aquatic system of the river and the terrestrial ecosystem
,on land. Riparian areas consist of the vegetation that grows along the banks of the river.
Species rich.
Four types of wetlands - Answer -Freshwater Marshes
Swamps
Bogs
Vernal Pools
Freshwater Marshes - Answer -Usually found at mouths of rivers and have shallow
water and vegetation that grows above the surface of the water, such as cattails and
bulrushes. Large stretches of freshwater marshes span much of the Florida Everglades
Swamps - Answer -Wetlands in forested areas
Bogs - Answer -Ponds covered in thick floating mats of vegetation and may be a
transitional stage of aquatic succession.
Vernal Pools - Answer -Seasonal wetlands that exist only during wet portions of the
year
Wetlands ecosystem services - Answer -Slowing runoff, reducing flooding, recharging
aquifers, and filtering pollutants
Lakes and Ponds are - Answer -Standing water with distinct zones.
Oligotrophic lakes and ponds - Answer -have low nutrient content and high oxygen
conditions. These lakes look clear and are support a variety of organisms. Oligotrophic
lakes can transform into eutrophic lakes.
Eutrophic lakes and ponds - Answer -lakes with high nutrient and low oxygen
conditions. The process of eutrophication is natural. As some lakes age over centuries,
there is a buildup of nutrients, sediment, and plant material, which slowly fill the lake
basin. Process end s and becomes colonized by terrestrial vegetation.
Littoral Zone - Answer -The nutrient rich edges of the water body, where the water is
shallow enough to allow aquatic plants to grow. This region has a rich diversity of
organisms including aquatic invertebrates such as insects, snails and crawfish, as well
as vertebrates such as birds, fish, turtles and amphibians.
Limnetic Zone - Answer -The open portion of the lake that is shallow enough to allow
sunlight to penetrate its entire depth. The sunlight enables photosynthesis to occur in
this zone, which means this area is teeming with photosynthetic organisms such as
algae, protists, and cyanobacteria.
Profundal Zone - Answer -The region below the limnetic zone. This region of the lake is
the open water of the lake that is too deep to allow light to reach it. The profundal zone
,does not have photosynthetic organisms and thus the dissolved oxygen levels are lower
in this zone compared to the limnetic zone.
Benthic zone - Answer -The portion of a lake that extends along the very bottom, from
the shore to the deepest point of the lake/pond. Invertebrates that live in this zone are
called benthic invertebrates and are often studied to assess the health of the aquatic
system.
Challenge of water - Answer -Unevenly distributed in space and time
Water mining - Answer -When we withdraw water faster than it can be replaced from
either surface water or ground water.
Ogalla Aquifer - Answer -Worlds largest known aquifer, found in the Great plains of the
U.S.
Several consequences of overdrawing an aquifer - Answer -Water tables drop
Wetlands dry up
Water becomes rarer/expensive
If near coast, salt water can intrude
Land will subside(sink)
Soil will become compacted, lose porosity, ultimately making recharge harder
Water use can be characterized as either - Answer -Consumptive or non-consumptive
us
Consumptive water - Answer -An activity that removes water from an aquifer or surface
water body and is not returned. For example, water used for irrigation.
Non-Consumptive - Answer -An activity that either does not remove water or only
temporarily removes water, such as is done with electricity generation at hydroelectric
dams.
A nuclear power plant removes water from a local river to cool the rods used to
generate energy. This water is released into the atmosphere as steam.
What type of water? - Answer -Consumptive
Dam - Answer -any obstruction placed in a river or stream to blow flow of water
Reservoirs - Answer -artificial lakes made by dams.
The largest dam is - Answer -Chinas Three Gorges Dam. 385 mile long reservoir, the
length of lake superior.
Pros and cons of dams/resevoirs - Answer -Pros
, - Irrigation
- Low carbon emissions
- Recreation(resrvoir)
- Renewable Energy
- Drinking Water
- Flood control
Cons
- Displacement of people
- Sediment build up behind dams
- RIsk of failure
- Habitat alteration (up/downstream)
- Soil build up at bottom
- Fisheries decline
- Lost rec activity (dam)
Desalination - Answer -The removal of salt from seawater is another option for creating
more supply. The problem with desalination though is that it is an energy intensive
process and requires a great deal of fossil fuels and electricity.
How can we reduce demand for freshwater? - Answer -Use drip irrigation instead of
flood and furrow or conventional irrigation
Xeriscaping - Answer -landscaping and gardening that reduces or eliminates the need
for irrigation. This is used in the southern U.S. and incorporates drought tolerant and
native species that require little to no supplemented water.
Reclaimed Water - Answer -water that is treated but not to the point that it is potable.
This type of water can be used to irrigate lawns, parks and golf courses and can be
used to flush toilets.
Majority of water is used for _______ - Answer -agriculture
Which of the following is not a consequence of overdrawing an aquifer? - Answer -
Subsidence; the rehydration of wetlands.
Freshwater pollution can come from either - Answer -Point sources or non-point sources
Point source pollution - Answer -direct discharge from a single location
- sewage treatment plants
- disposal sites
- factories
Non-point source pollution - Answer -indirect discharge that comes from multiple sites
over large areas
- lawns
- neighborhoods
