APES Chapter 9 Study Guide And Vocab

Total Flash Cards » 51
Text Size: S | M | L
Gully erosion cuts deeply into soil,leaving large gullies that expand as erosion proceeds
sheet erosion water flows in thin sheets over broad surfaces washing topsoil away in uniform layers.
rill erosion water runs along small furrow deepening them into rills.
splash erosion raindrops dislodge soil particles that fill in gaps between clumps, decreasing the soil’s ability to absorb water.
agriculture The practice of cultivating soil, producing crops, and raising livestock for human use and consumption.
soil A complex plant-supporting system consisting of disintegrated rock, organic matter, air, water, nutrients, and microorganisms. A renewable source that renews itself SLOWLY over time. Is considered an ecosystem because it inhabits many organisms like earthworms, mites and sow bugs.
horizon a distinct layer of soil
a horizon Topsoil. Made of inorganic/organic matter/humus mixed in. Takes its loose texture dark coloration and strong water holding capacity from Its humus content. Most NUTRITIOUS. Located below o horizon.
b horizon minerals and organic matter leach from e horizon into b horizon. This is subsoil, where they accumulate. Below e horizon.
c horizon Mainly of weathered parent material unaltered/slightly altered by the processes of soil
e horizon minerals and organic matter leach out of e horizon, below a horizon.
o horizon Uppermost layer. Mostly of organic matter deposited by organisms.
r horizon made of pure parent material. Bottommost layer.
Order of soil horizons O A E B C R.
Clay ediment consisting of particles less than 0.002 mm in diameter. Small particles, harder for water to pass through, slowing infiltration and reducing the amount of oxygen available to soil biota.
loam soil with a relatively even mixture of clay, silt, and sand-sized particles.
sand sediment consisting of particles 0.005-2.0 mm in diameter.
silt same as sand.
bedrock The continuous mass of solid rock that makes up Earth’s crust.
cation exchange

Process which plant’s roots donate hydrogen ions to the soil in exchange for cations (positively charged ions) such as those of calcium magnesium, and potassium, which plants use as nutrients. The soil particles then replenish these cations by exchange with soil water.

conservation district one of many county-based entities created by the soil conservation service to promote practices that conserve soil.
contour farming The practice of plowing furrows sideways across a hillside, perpendicular to its slope, to help prevent the formation of rills and gullies. The technique is so named because the furrows follow the natural contours of the land. Each furrow acts as a small dam slowing runoff and catching soil before its carried away. Most effective on gradually sloping land.
terracing The cutting of level platforms into steep hillsides to contain water from irrigation and precipitation. Transforms slopes into series of steps like a staircase, enabling farmers to cultivate hilly land while minimizing their loss of soil to water erosion. Most effective method of preventing erosion and is long term but is the only sustainable way to farm in mountain terrain.
crop rotation The practice of alternating the kind of crop grown in a particular field from one season or year to the next. It returns nutrients to the soil, break cycles of disease from cropping, and minimizes the erosion from fallow fields. Also reduces insect pests if they are adapted to a certain crop, and crop rotation contains soybeans, which are legumes that have specialized bacteria that fix nitrogen , revitalizing soil after other crops took nutrients from the soil.
cropland land that humans use to raise plants for food and fiber. One of the lands where we obtain most of our food and fiber from.
desertification A loss of more than 10% of a land’s productivity due to erosion, soil compaction, forest removal, overgrazing, drought, salinization, climate change, depletion of water sources, or other factors. Severe desertification can result in the actual expansion of desert areas or creation of new ones in areas that once supported fertile land.
dust bowl an area that looses huge amounts of topsoil to wind erosion as a result of drought and or human impact, first used to name the region in the North American Great Plans severely affected by drought and topsoil loss in the 1930’s.
erosion

the removal of material from one place and its transport to another by the action of wind or water.

fertilizer A substance that promotes plant growth by supplying essential nutrients such as nitrogen or phosphorus. Manure may introduce excess phosphorus that can leach through soil, contaminating groundwater, evaporate into air causing health risks(blue baby syndrome and cancer), and runoff into waterways causing eutrophication.
inorganic fertilizer fertilizer that consists of mined or synthetically manufactured mineral supplements. Are more susceptible than organic fertilizers to leaching and runoff and may be more likely to cause unintended off-site impacts.
organic fertilizer a fertilizer made up of natural materials (remains/wastes of organisms): animal manure, crop residues, fresh vegetation, and compost.
green revolution

an intensification of the industrialization of agriculture in the DEVELOPING world in the later half of the 20th century that has dramatically increased crop yields produced per unit area of farmland. –Practices: devoting large areas to monocultures of crops specially bred for high yields and rapid growth of heavy use of fertilizers, pesticides, and irrigation water and sowing and harvesting on the same piece of land more than once per year or per season. It increased yields and avoided starvation.

Green manure-organic fertilizer comprise of freshly dead plant material. Brazil’s farmers rely on this as well as legumes because they nourish the soil, and cover crops reduce weeds by taking up space the weeds might occupy.

industrialized agriculture a form of agriculture that uses large-scale mechanization and fossil-fuel combustion, enabling farmers to replace horses and oxen with faster and more powerful means of cultivating, harvesting, transporting, and processing crops. Other aspects include irrigation, the use of inorganic fertilizers. Use of chemical herbicides and pesticides reduces competition from weeds and pesticides reduces competition from weeds and herbivory by insects. Used monoculture and started the green revolution. Occupies 25% of world’s cropland.
traditional agriculture biologically powered agriculture, in which human and animal muscle power, along with hand tools and simple machines, perform the work of cultivating, harvesting, storing, and distributing crops.
subsistence agriculture farming families produce food for themselves. Intensive traditional agriculture, produce excess food to sell at markets. No use of fossil fuels.
intercropping planting different types of crops in alternating bands or other spatially mixed arrangements. Helps slow erosion by providing more ground cover and reduces vulnerability to insects/diseases and uses nitrogen fixing legumes.
irrigation the artificial provision of water to support agriculture. Can lead to waterlogging and salinization.
leaching the process by which solid materials such as minerals are dissolved in a liquid, usually water, and transported to another location.
monoculture the uniform planting of a single crop over a large area. Characterizes industrialized agriculture.
overgrazing

the consumption by too many animals of plant cover, preventing (impeding) plant regrowth and the replacement of biomass. Can cause a problem of damaging soils, natural communities, and the land’s productivity for further grazing. Soil is more vulnerable to erosion, invasive plants outcompete native vegetation, alter soil structure making it harder for water to infiltrate/aerate. Greater cause of DESERTIFICATION.

parent material

the base geological material in a particular location. Includes lava/volcanic ash. Rock or sediment deposited by glaciers, wind blown dunes and sediments from rivers/lakes/oceans.

rangeland or pasture, land used for grazing livestock. One of the places where we get most of our food and fiber, like croplands.
salinization the buildup of salts in surface soil layers. Irrigation contributes to this because the water added to the soil already has dissolved salts, so its just adding more salt to the soil.
shelterbelt A row of trees or other tall perennial plants that are planted along the edges of farm fields to break the wind and thereby minimize wind erosion. Combines with intercropping to form alley cropping, which mixed crops are planted in rows surrounded by rows of trees that provide fruit, wood, or protection from wind. Best way to prevent this is to avoid planting crops that require a huge amount of water. Also, irrigate with water low in salt content. And irrigate with only the amount of water needed.
topsoil Portion of soil most nutritious for plants and most direct importance to ecosystems and to agriculture. Also known as the A-horizon.
waterlogging The saturation of soil by water in which the water table is raised to the point that water bathes plant roots. It deprives roots of access to gases, suffocating them and damaging or killing the plants. Comes from overirrigated soils.
weathering

the physical, chemical, and biological processes that break down rocks and minerals turning large particles into smaller particles. Physical or mechanical weathering breaks rocks down without chemically changing the parent material. Main forces of physical weathering are wind and rain. Caused by water freezing/expanding in rock and areas with extreme temperature fluctuations. Chemical weathering is when water/other substances chemically interact with parent material. Accelerated by warm/wet conditions. Biological weathering is when living things break down parent material , accelerated by the decomposition of its leaves or chemicals released form its roots.

conservation reserve program

in 1985, paid farmers to stop cultivating (preparing/using) highly erodible cropland and instead place it in conservation reserves planted with grasses and trees.

NRCS (Natural Resources Conservation Service). This has reduced erosion, generated income for farmers, and provided habitat for native wildlife. Includes the Federal Agricultural Improvement and Reform Act (Freedom to Farm Act)-law aimed o reduce subsidies and government influence over many farm products. ->Created the Environmental Quality Incentive Program and the Natural Resources Conservation Foundation to promote and pay for the adoption of conservation practices in agriculture.

Low-Input Sustainable Agriculture Program provides funding for individual farmers to develop and practice sustainable agriculture.
Food and Agriculture Organization (FAO)- Internationally, the U.S. promotes soil conservation and sustainable agriculture through this.
Farmer-Centered Agricultural Resource Management Program (FAR)- from the FAO’s. it supports innovative approaches to resource management and sustainable agriculture in China, Thailand, Vietnam, etc. It studies agricultural success stories and tries to help farmers duplicate successful efforts. Educates and encourages farmers to conserve soils and secure their food supply.