unit 5 - land & water use

clear cutting

process of cutting down all the trees in an area at once— results in soil erosion, increased temps of soil and streams, and flooding + landslides

Green Revolution

agricultural revolution that increased food production through mechanization, GMOs, fertilization, irrigation, and pesticides

tilling

the turning-over of soil before planting; contributes negatively to soil quality by disrupting soil structure, accelerating erosion and runoff

slash and burn

farming method involving the cutting of trees, then burning them to provide ash-enriched soil for the planting of crops

synthetic fertilizer

fertilizers that are manufactured using chemical processes with the use of fossil fuels

drip irrigation

hoses w/small pores laid near roots

flood irrigation

flooding the field and letting water soak in

• cheap and easy, but disrupts plant growth and water is lost to evaporation + runoff

furrow irrigation

involves digging trenches and filling them with water, low effort and cheap but can cause water logging and salinization

spray irrigation

water is pumped through to sprinklers, higher efficiency but costs more and requires more energy

water logging

water completely saturates soil starves plant roots of oxygen, rots roots

pesticides

chemical intended to kill insects and other organisms that damage crops — pests can become resistant thru artificial selection

GMOs

new organisms created by altering the DNA of existing organisms; usually in an attempt to remove undesirable or create desirable characteristics in the new organism — can lead to a loss in diversity

CAFO

crowded livestock feeding operations that generates large amounts of waste, leading to contamination of local water sources

feedlot

a plot of land on which livestock are fattened for market, often less expensive

free-range grazing

raising livestock on large rangelands — can lead to overgrazing

• free from antibiotics and chemicals

• more expensive

overgrazing

loss of vegetation caused by too many grazing animals— causes soil erosion

desertification

degradation of low precipitation regions toward being increasingly arid — caused by desertification

overfishing

extreme fish scarcity, lessening aquatic BioD and harming fisheries

surface mining

removal of soil and rock (overburden) to access ore

IPM

combination of methods to control pests while minimizing environmental damage

contour plowing

agricultural technique in which plowing and harvesting are done parallel to the topographic contours of the land

windbreaks

belts of trees along field edges to reduce wind erosion

perennial crops

Crops that do not die off once harvested (annual crops), existing for years before reseeding may be required.

terracing

technique for farming that builds platforms on hills to reduce erosion

no-till agriculture

agricultural method in which farmers do not turn the soil between seasons, used as a means of reducing erosion; usually more weeds and use of chemicals

crop rotation

agricultural practice that involves planting different crops on the same land in a sequence, improving soil health, nutrient availability, and reducing pest/disease buildup

rotational grazing

regular rotation of livestock between different pastures in order to avoid overgrazing

aquaculture

cultivation of seafood under controlled conditions, only requires small areas of water and little fuel

• can contaminate wastewater

reforestation

using and buying wood harvested by ecologically sustainable forestry, including reusing wood

prescribed burn

method by which forests are set on fire under controlled conditions in order to reduce the occurrence of natural fires