Lecture 10 - Chapter 11 Flashcards
Water may seem abundant, but drinkable water is rare, true or false?
This true.
What is Freshwater?
Is relatively pure, with few dissolved salts
– Only 2.5% of Earth’s water is fresh, most is tie up in glaciers and ice caps
How does Water Moves Through the Hydrologic Cycle?
Water is constantly moving among the reservoirs via the hydrologic cycle:
• As water moves through the hydrologic cycle:
– stores and distributes heat
– erodes mountain ranges
– builds river deltas
– maintains ecosystems
– supports civilization
– gives rise to political conflicts
What is Residence times?
It storage time for water
• Reservoirs differ in resident times and amount of water they store
How much Water Supplies Our Households, Agriculture, and Industry?
Globally we use about 70% of annual freshwater allotment on agriculture:
- 5% is for cleaning
- 10% cooking, and drinking
- 20% laundry
- 30% Toilet flushing
- 35% showers and bath
Why is Water in situ Is Important for Both People
and Ecosystems?
• Water is critically important as a resource for human life and activities
• Water holds immense value in situ (“in place”)
• Freshwater systems are important for ecosystem services
– Both direct and indirect benefits
How Climate Change Will Cause Changes in the
Hydrologic Cycle?
• Climate change will affect the hydrologic cycle:
– shift northward in mid-latitude rain belt
– earlier snowmelt and spring runoff
– more evapotranspiration
– drier summers in the interior continental region
• Additional impacts:
– warmer rivers (impacting fish) – thermal pollution
– lower water levels in Great Lakes
– higher ocean water levels
What are freshwater systems?
Water from rain, snowmelt, or springs forms
streams, creeks, or brooks
What merge into rivers, and eventually
reaches the ocean?
– Tributary = a smaller river slowing into a
larger one
– Drainage basin or watershed = the area of land drained by a river and its tributaries
If there is a large bend in the river, the force of the water cuts through the land by _________
– Oxbow = an extreme bend in a river
– Oxbow lake = the bend is cut off and remains as an isolated, U-shaped body of water
What is Floodplain?
areas nearest to the river’s course that are
flooded periodically
– Frequent deposition of silt makes floodplain soils fertile
What is Riparian?
riverside areas that are productive and species-rich
Water of rivers and streams hosts diverse ecological communities true or false?
True
How are Wetlands Are Diverse and Complex? What are the different wetlands?
• Wetlands
• Freshwater marshes
• Swamps
• Bogs
Wetlands Are Diverse and Complex, what are wetlands?
Are systems that combine elements of freshwater
and dry land
Wetlands Are Diverse and Complex, what are Freshwater marshes?
shallow water allows plants to grow above the water’s surface
Wetlands Are Diverse and Complex, what are Swamps?
shallow water that occurs in forested areas
– Can be created by beavers
Wetlands Are Diverse and Complex, what are Bogs?
Are ponds covered in thick floating mats of vegetation
– A stage in aquatic succession
What are wetlands for wildlife?
• Wetlands are extremely valuable for wildlife
• They:
– slow runoff
– reduce flooding
– recharge aquifers
– filter pollutants
• People have drained wetlands, mostly for
agriculture
– Southeastern (Potholes region) Canada
has lost more than half of their wetlands
What are lakes and How does Lakes Contain Open, Standing Water?
They have:
• Lakes and ponds are bodies of open, standing water
• Littoral zone
• Benthic zone
• Limnetic zone
• Profundal zone
Lakes Contain Open, Standing Water, what is Littoral zone?
Is the region ringing the edge of a water body
Lakes Contain Open, Standing Water, what is Benthic zone?
Extends along the entire bottom of the
water body
– home to many invertebrates
Lakes Contain Open, Standing Water, what is Limnetic zone?
open portions of the lake or pond where
the sunlight penetrates the shallow waters
Lakes Contain Open, Standing Water, what is Profundal zone?
water that sunlight does not reach
– supports fewer animals because there is less oxygen
