APES Unit 4

traditional agriculture

cultivating, harvesting, storing, and distributin crops is perfomed by human and muscle power

industrial agriculture

agriculture that uses large scale mechanization, fossil fuel combustion, and inorgnaic fertilizers

sustainable agriculture

agriculture that maintains a healthy environment and can be used far into the future

mycorrhizae

a symbiotic relationship between fungi and plant roots

parent material

the base geological material in a particular location

bedrock

the mass of solid rock that makes up the Earth's crust

weathering

the phyiscal, chemical, and biological processes that convert large rock particles into smaller particles

humus (relationship with moisture)

dark, spongy, crumby mass of material made up of organic compounds

soils with high humus content hold moisture well

5 main influences

climate, organisms, topography (hiils and valleys), parent material, and time

soil profile

soil as a whole, including all soil horizons from the surface to bedrock

O horizon

organic matter deoposited by organisms

A horizon

topsoil, some organic material mixed with mineral componenets. is the layer that is most nutritive

E horizon

leacing layer, minerals and organism matter tend to leach out of this horizon

B horizon

subsoil, minerals and organic matter accumulate here

C horizon

weathered parent material, initial step in soil formation

R horizon

rock, is the parent material, bedrock, lava, etc

weatering and soil profile relationship

the degree of weathering and the concentraiton of organic matter decreases as one moves downward in a soil profile

leaching

the process by which minerals dissolved in a liquid(water) are transported to another location (downward through soil horizons)

Soil is classified by 4 categories...

color, texture, structure, and pH

color (soil classification)

blakc or dark brown soilds are usually rich in organic matter while a pale color indicates a histroy of leaching

texture (soil classification)

tecture is determined by the percentage of clay, silt, and sand in soil

structure (soil classification)

measure the clumpiness of the soil (intermediate is best), compacted soil has a reduced ability to absorb water and inhibits the penetration of plant's roots

pH (soil classification)

plants can die in soil that is too acidic or basic, so intermediate pH levels are best, acids may leach nutrients from the soil

Regional soil differences

warm temperatures usually have little humus, soils in the amazon forest are not productive because the rain leaches minerals before it can reach plant roots

waterlogging

when overirrigation saturates the soil and causes the water table to rise to the point where the plant drowns

salinization

the buildup of salts in surface soil layers, usually happens where precipiation and humidity are low, is hastened by irrigatin in arid areas

drip irrigation

targets plant roots directly, allowing 90% of the water to actually be useful

inorganic fertilizers

mined or synthetically manafactures mineral supplements

organic fertilizers

consists of the remains of wastes of organisms

compost

mixture composed when decomposers break down organic matter such as food and crop waste in a controlled environement

pollination

process by which male sex cells of a flowering plant (pollen) fertilize female sex cells of a flowering plant (egg cells)

colony collapse disorder

a mysterious diseases that for the past decade has destroyed up to 1/3 of all honeybess in the U.S.

neonictonoid pesticides

a pesticide spread throughout the plants tissue so any insect eating the plant will die

landdraces

genetically diverse variety of a crop that has adapted to local conditions

seed banks

institutions that preserve seed types as a kidn of living museum of genetic diversity

soil degradation

process where soil deteriorates in quality and declines in productivity

erosion

the removal of material from once place and it's transport to another by wind or water 9usually removes topsoil)

deposition

the arrival of eroded soil at a new location

desertification

a form of land degradation in which more than 10% of productivity is lost as a result of erosion, soil compaction, forest removal, overgrazing, drought, salinization, water depletion, etc

dust bowl

an area that loses huge amounts of topsoil to wind erosion as a result of drought and/or human impact (1930's)

soil conservation act

establised the natural resources conservation service which helped develop conservation plans and control pollution

crop rotation

alternating the type of crop rown in a given field from one season or year to the next

contour farming

consists of plowing furrows sideways across a hillside, perpendicular to it's slope and following the natrual contours of the land

terracing

transforms slopes into a series of steps like a staircase, enabling farmers to cultivate hilly land without losing large amounts of soil due to water erosion

intercropping

planting different crops in alternating bands or other spatially mixed arrangements

shelterbelts

rows of trees or tall shrubs planted along the edges of diels to slow the wind

conservation tillage

ecompasses approaches that reduce tilling; turning soil which aerates it and works weeds and old crop residue into the soil to nourish it

conservation reserve program

pay farmers to stop cultivating higly erodible cropland and instead to place it in conservation reserves plantes with grasses and trees

law of conservation of matter

law stating that matter may be transformed into another substance but can't be created or destroyed

isotope

when particles have the same number of protons but different number of neutrons

half life

amount of time it takes for one half the atoms of a radioisotope to decay

covalent bond

a chemical bond where atoms share electrons

hydrogen bond

a weak bond between molecules due to the attraction ofpartial positive and partial negative charges

ionic bonds

chemical bond where electrons are transferred between atoms creating oppositely charges ions that bond

hydrocarbons

an organic compound consisting of hydrogen and carbon atoms

macromolecules

proteins, nucleic acids, carbohydrates, lipids

kinetic energy

the energy in a object due to it's motion

potential energy

the stored energy in an object due to its position or composition

Luster

the reflection(shine) of a mineral. Metallic, glassy, waxy, pearly, brilliant, dull, and earthy.

cleavage and fracture

cleavage is the mineral that splits along a plane of weakness to form smooth surfaces. Fracture is an irregular surface break.

Hardness:

the ability to resist scratching. The Mohs hardness scale is used. Diamonds are the hardest mineral and Talc is the softest

Crystal Shape

there are 6 shapes that can form depending on temperature and pressure. Fast = small crystals, slow = large crystals

Mineral

a natural, usually inorganic solid, that has a characteristic chemical composition, an orderly internal structure, and a characteristic set of physical properties.

Shadow Zones

area where body waves are not detected