Landscapesand

Landscape Development

Topic 14 in Review Book

A. ESRT page 2 used with page 3 shows the landscape regions of NYS and the associated bedrock.

Be familiar with the use of these pages

B. Factors that influence landscape formation

1. Climate:a. Type and amount of

precipitation: arid vs humid

Arid climates result in angular features with steep slopes

Humid climates result in rounded features with gentle slopes

b. Type and amount of vegetation:

Vegetation prevents excessive weathering and erosion resulting in more gentle slopes

c. Range in temperatured. Duration and velocity of

winds

2. Rock Type

Resistance to weathering influences landscape development

Resistant bedrock results in steep, angular slopes

Nonresistant bedrock results in gentle, rounded slopes

Variations in resistance creates unique landscape formations such asescarpments (cliffs)waterfalls

3. Geologic Structures

Used to classify landscape regions

Are tied to changes in bedrockIndicate landscape boundaries

Faulted and/or folded bedrock create characteristic landscape features

C. Drainage Patterns

Bedrock and its various structures result in characteristic patterns of ground and surface water drainage

See Review Book page: 274 & 275

D. Landscape Features

See definitionsSee the pictures throughout topic 14 that illustrate the different landscape formations and rock types.

V. HydrologyThe study of water in, on and around the earth.

A.The water cycleA model of the movement and changes in phase of water at and near the surface of the earth.

1. Evapotranspiration: A combination of: The evaporation of surface

and subsurface water and the release of water vapor

through the pores of leaves. The source of atmospheric

water vapor!

2. PrecipitationThe source of water for the earth

3. Water and Climate:ET > PPT = dry or aridET < PPT = wet or humid

Storage:Ground water and surface waters

Surplus:Excess waterDeficit:Insufficient water

4. Concepts of the Water Cycle

Infiltration:The process by which water soaks into the ground under the influence of gravity

The water table is the limit of infiltration

If the ground is saturated (holding all of the water it can hold) infiltration cannot occur.

If the ground is frozen, infiltration will not occur.

If precipitation is rapid and/or intense, infiltration is less likely to occur.

If the slope is steep, infiltration is less likely to occur.

If the ground is covered with pavement and/or buildings, infiltration is not likely to occur.

If the soil is impermeable, infiltration cannot occur.

Permeable soil or sediment allows water to flow down through it.

Porosity is the percentage of open space within a soil sample and indicates the ability of a material to hold water in those open spaces. Porosity depends upon the interconnectedness of the spaces between the sediment.

Well-sorted sediments with around grains have a high porosity.

Size does NOT affect porosity!Shape and degree of sorting does!

Porous sediment is very permeable.

As porosity increases, permeability increases

As degree of sorting increases, porosity increases and permeability increases

As roundness increases, porosity increases and permeability increases.

B. Water Table

The interface between the zone of aeration and the zone of saturation.

Its depth fluctuates and is dependent on the amount of available moisture.

At times of moisture surplus, the water table is located closer to the surface…the depth of the water table decreases!

At times of moisture deficit: the water table is located farther from the surface…the depth of the water table increases!

Zone of saturation

Zone of aeration Zone ofaeration

Normal water table

Surplus depth

Deficit depth

The end!