4.2 Soil Formation & Erosion

Question 1

Plants: Anchor ____ of plants and provides _______, shelter, ______ for growth.

Answer 1

roots, water, nutrients

Question 2

Water: Filters __________ + runoff by trapping ________ in pore spaces + plant _____. Clean water enters __________ + aquifers

Answer 2

rainwater, pollutants, roots, groundwater

Question 3

Nutrient Recycling: home to _________ that break down dead ______ matter + return _______ to the soil

Answer 3

decomposers, organic, nutrients

Question 4

Habitat: Provides _______ for org. like earthworms, _____, bacteria, moles, ____

Answer 4

habitat, fungi, slugs

Question 5

What is Soil?

Answer 5

Mix of geologic (rock) and organic (living) components

Sand, Silt, Clay

Question 6

What is Soil?

Humus: Main ________ part of soil (broken down ______ like leaves, dead _______, waste, etc.)

Answer 6

organic, biomass, animals

Question 7

What is Soil?

Nutrients: __________ _________, _________

Water and Air

Living Organisms

Answer 7

Ammonium nitrates phosphates

Question 8

Weathering

Breakdown of _____ into smaller pieces

Physical (wind, rain, freezing/______ of ice)

Biological (roots of trees _____ rocks)

Chemical (acid rain, ______ from moss/lichen)

Answer 8

rocks

thawing

crack

acids

Question 9

Weathering of _____ = soil formation

Broken into _______ and _______ pieces

Carried away and deposited by _______

Answer 9

rocks

smaller

erosion

Question 10

Erosion

Transport of ________ rock __________ by wind and rain

Carried to new _______ and deposited (deposition)

Answer 10

weathered, fragments

location

Question 11

Soil Formation

From below

Weathering of _______ material produces smaller, and smaller _______ that make up geological/inorganic part of ____

Answer 11

parent, fragments, soil

Question 12

Soil Formation

From above

Breakdown of organic matter adds _____ to soil

Erosion ______ soil particles from other areas, adding to ___

Answer 12

humus

deposits, soil

Question 13

Effects on Soil Form

Parent material: Soil pH, _________ content

Topography: Steep slope = too much _______; more level ground = deposition

Climate: warmer = _____ breakdown of organic matter more ________ = more _______, erosion + deposition

Organisms: Soil organisms like _______, fungi, worms breakdown organic matter

Answer 13

Nutrient

erosions

faster

precipitation

weathering

bacteria

Question 14

O-Horizon: Layer of _____ matter (plant roots, dead leaves, animal waste, etc) on ___ of soil

Answer 14

organic

top

Question 15

A-Horizon: aka topsoil; layer of humus (__________ organic matter) and minerals from ______ material

Answer 15

decomposed

parent

Question 16

A-Horizon has most ________ activity (earthworms, soil microbes) breaking down organic matter to _______ nutrients

Answer 16

biological

release

Question 17

B-Horizon: aka _______; lighter layer below topsoil, mostly made of ______ w/little to no org. matter

-Contains some nutrients

Answer 17

subsoil

minerals

Question 18

C-Horizon: Least _______ soil that is closet to the parent material, sometimes called ________

Answer 18

weathered

bedrock

Question 19

Loss of Topsoil: tiling (turning soil for ________) + loss of __________ disturb soil and make it more easily _______ by wind and rain

Loss of top soil dries out soil, removes _______ + soil organisms that ______ nutrients

Answer 19

agriculture, vegetation, eroded

nutrients, recycle

Question 20

Compaction: Compression of soil by machies (tractors, bulldozers, etc.) _______ livestock, and humans reduces ability to ___ moisture

Dry soil _______ more easily

Dry soil ________ less plant growth, less root ________, leading to more ________

Answer 20

grazing, hold

erodes

supports, structure, erosion

Question 21

Soil Degradation

Answer 21

the loss of the ability of soil to support plant growth

Question 22

Nutrient Depletion: ________ growing crops on the same soil __________ key nutrients over time

Reduces ability to ____ future crops

Answer 22

Repeatedly, removes

grow