Environmental Sci - Land Part One Test

What are the 4 ways to classify soil?

color, texture, structure, pH

wind and rain

Two main causes of physical weathering

humus

partially decomposed organic matter; dark, spongy material made up of complex organic compounds

crop rotation

alternating crops grown in a field

sand

largest soil particle

clay

smallest soil particle

silt

a soil particle that is larger than clay and smaller than sand

How do plants help to protect soil from erosion?

slowing wind and water
roots hold soil in place and absorb water

shelterbelt

rows of trees or other tall plants

deposition

the drop off of eroded material at a new location

tilling

turning over of soil before planting

overgrazing

causes the compaction of soil, greater soil exposure, nonnative plants invading exposed areas, and increased wind and water erosion

1930s

In what decade did the Dust Bowl occur?

yield

the amount of crop produced in a given area

monoculture

growing a single crop over a large area

weathering, decomposition, deposition

What are the processes through which soil is formed?

38%

Approximately what percentage of land is used for agriculture?

human activity

What is the cause of most erosion?

loam

soil with a relatively even mixture of clay, silt, and sand

parent material

the base geological material in a particular location

soil degradation

the deterioration of the soil characteristics needed for plant growth or other ecosystem services

desertification

the loss of more than 105 of productivity due to erosion, soil compaction, forest removal, overgrazing, drought, and other processes

sustainable ranching

occurs when the grazing animals' populations stay within an ecosystem's carrying capacity

contour farming

plowing sideways across a hillside, perpendicular to the hill's slope

terracing

creating a series of steps, like a staircase

salinization

the build up of salts in the upper layers of soil

broad spectrum

A pesticide that kills a variety of organisms is described as being what?

the Green Revolution

involved developed countries creating strains of corn, rice, and wheat with larger seed heads and disease resistance; very high crops yields; use of irrigation and machinery; these crops and techniques were then shared with developing nations

Name negative impacts of agriculture that got worse with the Green Revolution.

erosion, salinization, eutrophication, pollution

Bacillus thuringiensis

a type of bacteria in the soil that kills the larvae of many pests

intercropping

planting of different crops in mixed arrangements

Agent Orange

the name of the pesticide used during the Vietnam War to thin out the jungle

What does IPM stand for?

integrated pest management

What does IPM involve?

gaining extensive knowledge of the pest
combining several different techniques
using chemical pesticides as a last resort and in the smallest quantities needed

pollinators

insects, bats, honeybees, and hummingbirds are all what kind of organism?

increased fossil fuels
use of machinery
irrigation improvements
use of synthetic fertilizers
use of chemical pesticides

List 5 changes to agriculture that occurred between the arrival of the Industrial Revolution and the mid-1900's.

Explain how irrigation can lead to increased salinization of crop land.

Use of lots of water means water goes into the lower layers of soil.
The water in the lower layers picks up dissolved salts.
When water evaporates from the surface, it pulls water up through the layers of soil, bringing dissolved salts up with it. The salts get left behind at the surface.