2nd Grading Earth Science

SOIL

This is a part of the regolith that supports the growth of plants

MINERAL MATTER, HUMUS, WATER, AIR

4 components of soil

HUMUS

These are decayed remains of organisms

REGOLITH

These are layers of rocks and mineral fragments that cover the earth’s land surface

SOIL HORIZONS

These are zones or layers of soils

SOIL PROFILE

These are vertical section of the soil horizons

O, A, E, B, C, R

letters of the arrangment of soil profile

O (ORGANIC LAYER)

layer where organic materials/humus are present

A (TOPSOIL)

layer where minerals with humun are present

E (ELUVIATION LAYER)

layer that is light-colored with eluviaton and leaching

B (SUBSOIL)

layer that is a zone of accumulation/deposited minerals and metals salts

C (PARENT ROCK)

a layer that is partially altered parent materials/weathered rock

R (BEDROCK)

layer that unweathered parent rocks are present

SOIL QUALITY

assessing and managing soil so that it functions properly for future use.

SOIL QUALITY

The capacity of a specific kind of soil to funtion; to sustain plant and animal productivity; enahnce water and air quality; support human health and habitation

LAND MANAGER

The one that can determine if a set of practices are sustainable.

FOR PEOPLE ACTIVE IN PRODUCTION AGRICULTURE

For them, it may mean a highly productive land, maximizing profits, maintaining soil resources for future generations

FOR CONSUMERS

For them, it may mean pleantiful, healthful, and inexpensive food.

FOR NATURALISTS

For them, it may mean soil in harmony with landscapes and its surroundings

FOR ENVIRONMENTALISTS

For them, it may mean soil functioning to maintain the enhancement of biodiversity, water quality, nutrient cycling, and biomass production.

REGULATING WATER, SUSTAINING PLANT AND ANIMAL LIFE, FILTERING POTENTIAL POLLUTANTS, CYCLING NUTRIENTS, SUPPORTING STRUCTURES

What does soil do?

SOIL DEGRADATION

physical, chemical, and biological decline in soil quality due to erosion

LOSS OF NUTRIENTS AND ORGANIC NUTRIENTS, SALINIZATION, ACIDIFICATION, POLLUTION, COMPACTION AND SUBSIDENCE

5 soil degradation processes due to erosion

FARMING, CONSTRUCTION AND DEVELOPMENT, MINING, WASTE DISPOSALS

4 major human activities that cause soil degradation

FARMING

when farmers clear land; american farmers lose about 5 metric tons of soil for every ton of grain they produce

POSITIVE

What effect does the application of herbicide, a pesticide used to kill unwanted plants, to the soil?

NEGATIVE

What effect does tillage (preparation of soil and cultivation after plant) do to the soil?

CONSTRUCTION AND DEVELOPMENT

grading and filling reduce soil quality. Land use conversion usually done to support urbanization activities cause rapid soil degradation

STRIP MINING AND OPEN PIT MINING

This involves the removal of plants

ACID DRAINAGE

This is a type of pollution from the speed up of chemical weathering. This acid can seep into the soil and can be harmful to plants trying to grow.

WASTE DISPOSALS

When hazardous chemicals from human and industrial sewage are carelessly disposed.

FOREST PROTECTION, BUFFER STRIPS, NO TILL FARMING, FEWER CONCRETE SURFACES, PLANT WINDBREAK AREAS, TERRACE PLANTING, AFFORESTATION, NO SOIL COMPACTING, CONTROL STORM WATER

9 ways to protect and conserve the soil

BUFFER STRIPS

This reduce water and wind erosion, provides protection where stream banks exist, created with grass, trees, and shrubs.

NO-TILL FARMING

This is an approach that allows crops to remain in place for a season

FEWER CONCRETE SURFACES

This uses paving stones for patios and gardens work to protect the soil.

PLANT WINDBREAK AREAS

This will work together to slow the force of wind over ground areas.

TERRACE PLANTING

Type of planting by maximizing the topography of the land, rain water flows naturally, encourage growth from moist soil areas

AFFORESTATION

tree planting method where in the areas under trees are protected; planting foliage in forest undergrowth areas.

NO SOIL COMPACTING

This helps not to walk on wet soil causing it to be compacted

CONTROL STORM WATER

setting up larger container to hold excess water in problem locations.

WEATHERING

physical disintegration or chemical alteration of rocks at or near the earth’s surface

EROSION

physical removal and transporation of weathered material by water, wind, ice, or gravity.

MASS WASTING

the transfer or movement of rocks or soil down slope primarily by gravity

DEPOSITION

process which weathered and eroded materials are placed in a different location from their source

MECHANICAL, CHEMICAL, BIOLOGICAL

3 types of weathering

MECHANICAL WEATHERING

physical disintergration and reduction in the size of the rocks without changing their chemical composition

EXFOLIATION, FROST WEDGING, TEMPERATURE CHANGES, SALT WEDGING, ABRASION

5 types of mechanical weathering

EXFOLIATION

layers of rocks break off from the bedrock and move downhill by gravity.

EXFOLIATION DOME

large rocks characterized by exfoliation. Examples of this are the Table rock mountin in South Carolina and Enchanted rock in Texas

FROST WEDGING

when water freezes, it expands and applies pressure to the surrounding rock and this gradually weakens, cracks, and breaks the rock through repetitive freeze thaw.

TALUS

These are rock fragments that are deposited at the base of a hill slope or mountain

TEMPERATURE CHANGES

The gradual expansion (warm temperature) and contraction (cool temperature) of mineral grains weakens the rock causing it to break apart into smaller fragments.

SALT WEDGING

Salts crystallize due to water evaporation, and this applies pressure to the rocks causing it to weaken and breaks down

ABRASION

rocks collide against each other while being transported by water, glacial ice, wind, or gravitational force.

FLOWING WATER

primary medium of abrasion and produces “rounded” shape of fluvial sediments.

CHEMICAL WEATHERING

decomposes, alters, or weakens the rock through chemical processes to form residual materials.

CARBONATION, HYDROLYSIS, HYDRATION, OXIDATION, SOLUTION

5 types of chemical weathering

CARBONATION

combination of carbon dioxide and rain water that chemically reacts to produce carbonic acid

CARBONIC ACID

this is a weak acid that reacts with carbonate minerals in the rock that causes the rock to weaken.

HYDROLYSIS

chemical reaction between H+ ions in the water react with minerals to produce weak acids and creates new compounds which tend to be softer and weaker than the original parent rock.

HYDRATION

A mineral structure in the rocks forms a weak bond with H2O which causes the minerals to expand and causes rocks to disintegrate. This is also accompanied by hydrolysis and oxidation, also increases size of the rock and can lead to decay.

OXIDATION

When oxygen and water react with iron-rich minerals and weaken the structure of the mineral and causes the rocks to have a ‘rusty’ reddish-orange appearance

SOLUTION

when minerals in rocks dissolve directly into water.

BIOLOGICAL WEATHERING

disintegration or decay of rocks caused by chemical or physical agents of organisms.

ORGANIC ACTIVITY BY LICHEN AND ALGAE, PLANT ROOTS, ORGANISM ACTIVITY, DIFFERENTIAL WEATHERING

4 types of biological weathering

ORGANIC ACTIVITY FROM LICHEN AND ALGAE

these organisms often live on bare rock and extract minerals by ion-exchange mechanisms and causing it to weaken and breakdown

PLANT ROOTS

these penetrates into crachs that may already have pre-existing weakness and the plant roots just causes the rock to continually split or break into smaller particles.

ORGANISM ACTIVITY

organisms may tunner into rocks and causes the rocks to break down and some organisms attach themselves to rocks to secrete acids that dissolve in the rocks causing it to weaken/decay.

DIFFERENTIAL WEATHERING

differences in rates of weathering due to different types of rocks, textures, or other characteristics.

WATER, WIND, ICE, GRAVITY

4 components of erosion

WATER

this erodes rocks and shapes the landscapes by removing and transporting weathered materials from their souce to another location

RAIN-SPLASH EROSION, SHEET EROSION, RILL EROSION

3 categories of fluvial erosion (water)

RAIN-SPLASH EROSION

When the impact of a rain drop lossesns and mobilizes particles.

SHEET EROSION

particles that are loosened from the rain-splash erosion are transported through a run-off water down the slope of a source

RILL EROSION

water concentrates during sheet erosion and erodes small rills or gullys into the surface that channel flow down slope.

WIND

erodes rocks by picking them up and temporarily transporting them from their source to another location

DEFLATION, ABRASION

2 categories of Aeolian erosion (air)

DEFLATION

movement of particles through the air or along the ground

ABRASION

wind-transported paarticles sculpt features in the landscape through a “sand-blasting” process.

ICE

this occuers in combination with periglacial and glacial processes

GLACIAL EROSION

when particles are incorporated into the glacial ice through a process referred to as plucking

GRAVITY

down slope transporation of weathered materials

COHERENT AND INCOHERENT

2 types of gravity

COHERENT

consolidated mass of minerals that erode as a single unit

INCOHERENT

unconsolidated movement of a mass individual frag.

35 DEGREES

unconsolidated movement tend to stabilize near an angle of _______

ANGLE OF REPOSE

the angle of 35 degrees in the stabilization of the unconsolidated movement is also callled

ROCK FALLS, LANDSLIDES, DEBRIS, SLUMP, CREEP, DEPOSITION

6 types of mass wasting

ROCK FALLS

rocks become dislodged and the potential energy becomes kinetic energy which causes rock fragments to fall

LANDSLIDES

mass-wasting events where large amounts of weathered rock materials slide down a hillslope/mountain by gravity

DEBRIS

heavy rainfalls produce large amounts of run off that transport eroded soils, sediments, and plant debris down slope

SLUMP

rock or soils collpases, breaks off from the hill slope, rotates slightly, and slumps downhill

CREEP

slowest mass-wasting process that involves a very gradual downhill movement of soil, bedrock, and weathered rock fragments.

SOLIFLUCTION

A certain form of creep where frozen tundra soils thaw out and gently ‘flow’ or sag downslope

COLLUVIUM

eroded rocks, soil, and sediments deposited at the base of a hill slope or cliff by gravity

ALLUVIUM

materials that are deposited by running water.

PHYSICAL WEATHERING

What type of weathing?

Grinding of rocks for building construction

CHEMICAL WEATHERING

What type of weathing?

U-Shaped valley developed out of moving glacier

CHEMICAL WEATHERING

What type of weathing?

Rockss changed colors from graying to reddish or brown

PHYSICAL WEATHERING

What type of weathing?'

Water froze within rocks vesicles exerting force on walls and breaking the rock