Midterm 2

Question 1

Thalweg

Answer 1

Where water velocity is maximum at the center

Question 2

Which location has the highest residence time?

Answer 2

Icecaps/glaciers - 12,000 yrs

Question 3

Floodplain

Answer 3

Area of low-lying ground adjacent to river, formed mainly of river sediments and subject to flooding

Question 4

Base flow

Answer 4

Infiltration through soil and sediments that feeds into stream to maintain flow

Question 5

Runs

Answer 5

Areas with rapidly moving water but with a smooth surface

Question 6

Stream classification: Snowmelt

Answer 6

• Seasonally strong on biota
• Rare drying
• Infrequent & predictable floods
• High discharge predictability

Question 7

Intermittent

Answer 7

Flowing some of the time and receiving water from groundwater

Question 8

Riffles

Answer 8

Areas where influence of bottom can be seen at surface of flowing water; shallow or turbulent areas

Question 9

Orthofluvial

Answer 9

Remaining floodplain

Question 10

Stream classification: Perennial runoff

Answer 10

• Strong to intermediate effect on biota
• Rare drying
• Infrequent flooding
• Low discharge predictability

Question 11

Gaining streams

Answer 11

Streams with increased discharge from groundwater as they move downstream

Question 12

A straight channel has a sinuosity of?

Answer 12

1

Question 13

Sinuosity

Answer 13

Distance the water travels between 2 points divided by the direct distance between the 2 points

Question 14

Types of water use by humans

Answer 14

1. Domestic (high-quality water)
2. Power (low-quality water)
3. Consumptive (ex. agriculture evaporation)

Question 15

Stream classification: Winter rain

Answer 15

• Seasonally strong effect on biota
• Rare drying
• Infrequent & predictable floods
• High discharge predictability

Question 16

Stream classification: Intermittent runoff

Answer 16

• Strong effect on biota
• Rare drying frequency
• Frequent & unpredictable floods
• Low discharge predictability

Question 17

T/F: If all people in the world used water at the per capita rates used in the US, all water available would be used

Answer 17

True

Question 18

Water velocity

Answer 18

Speed of water at any point in a channel

Question 19

Pools

Answer 19

Deep areas with relatively low water velocity

Question 20

Variable source area hydrology

Answer 20

Expansion and contraction of saturated areas in watershed during wet and dry periods

Question 21

Parafluvial

Answer 21

Where river regularly floods

Question 22

Discharge equation

Answer 22

Discharge (Q) = velocity (V) x channel surface area (A)

Question 23

Reach

Answer 23

A section of river with multiple riffles/pools/runs

Question 24

Which location has the lowest residence time?

Answer 24

Atmosphere - 8.9 days

Question 25

Stream classification: Snow & rain

Answer 25

- Strong to intermediate effect on biota - Rare drying - Frequency & predictable floods - Low discharge predictability

Question 26

Watershed

Answer 26

Land area drained by all tributary streams above a chosen point in the main channel

Question 27

Fluvial zone

Answer 27

Flowing channel

Question 28

Globally, humans currently withdraw ____% of runoff that is accessible

Answer 28

54%

Question 29

Discharge

Answer 29

Volume of water passing through a channel per unit of time

Question 30

Stream classification: Mesic groundwater

Answer 30

- Weak effect on biota - Rare drying - Infrequent floods - High discharge predictability

Question 31

Which water source provides the most fresh water for humans?

Answer 31

Groundwater - 96.56% | Although it's difficult to reach

Question 32

What is the global hydrologic cycle?

Answer 32

The estimated amount of water movement between compartments throughout the globe

Question 33

Losing streams

Answer 33

Streams with decreasing groundwater flow due to their location at a level above groundwater

Question 34

Stream classification: Intermittent flashy

Answer 34

- Strong effect on biota - Low drying frequency - Frequent flood/discharge frequency

Question 35

Rosgen system first level

Answer 35

Characterizes stream by channel and valley shape, slope and pattern

Question 36

Stream classification: Harsh intermittent stream

Answer 36

- Strong effect on biota - Low drying frequency - Rare to frequent flood/discharge frequency

Question 37

Hydrograph

Answer 37

Plot of discharge against time

Question 38

Perennial

Answer 38

Flowing all of the time, or most of the time when not in a drought event

Question 39

What is a hydrologic flux?

Answer 39

Movement of water thru the global hydrologic cycle

Question 40

Ephemeral

Answer 40

Flowing rarely and not receiving input from groundwater

Question 41

Pothole / Kettle

Answer 41

Formed when ice left from retreating glacier is buried in till and melts

Question 42

Moraine

Answer 42

Glacial activity deposits a dam of rock and debris

Question 43

Graben

Answer 43

Block slips down btwn two others

Question 44

Horst

Answer 44

Diagonal slippage

Question 45

Earthslide

Answer 45

Movement of earth dams a stream or river

Question 46

Volcanic-caldera

Answer 46

Volcanic explosion causes hole that fills with water

Question 47

Dissolution

Answer 47

Limestone dissolves and lake forms

Question 48

Oxbow

Answer 48

River bend pinches off, leaves lake behind

Question 49

Lentic

Answer 49

Non-flowing water

Question 50

Glacial lake: Cirque

Answer 50

Deep glacial scours create valleys where lake can form

Question 51

Glacial lake: Fjord

Answer 51

Long, glacial lakes in steep valleys

Question 52

Pelagic zone

Answer 52

Open water of lake, water column above sediments where there is not enough light for photosynthesis

Question 53

Profundal zone

Answer 53

Benthic habitat below pelagic zone

Question 54

Littoral zone

Answer 54

Shallow zone of lake where enough light enters to allow growth of photosynthetic organisms

Question 55

Fetch

Answer 55

Length of lake on which the wind acts

Question 56

Seiche

Answer 56

Rocking of entire lake's surface