Gully erosion |
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cuts deeply into soil,leaving large gullies that expand as erosion proceeds |
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sheet erosion |
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water flows in thin sheets
over broad surfaces washing topsoil away in uniform layers. |
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rill erosion |
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water runs along small
furrow deepening them into rills. |
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splash erosion |
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raindrops dislodge soil
particles that fill in gaps between clumps, decreasing the soil’s ability to
absorb water. |
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agriculture |
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The practice of cultivating
soil, producing crops, and raising livestock for human use and consumption. |
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soil |
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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. |
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horizon |
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a distinct layer of soil |
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a horizon |
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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. |
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b horizon |
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minerals and organic matter
leach from e horizon into b horizon. This is subsoil, where they accumulate.
Below e horizon. |
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c horizon |
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Mainly of weathered parent
material unaltered/slightly altered by the processes of soil |
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e horizon |
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minerals and organic matter
leach out of e horizon, below a horizon. |
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o horizon |
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Uppermost layer. Mostly of organic matter deposited by
organisms. |
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r horizon |
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made of pure parent
material. Bottommost layer. |
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Order of soil horizons |
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O A E B C R. |
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Clay |
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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. |
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loam |
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soil with a relatively even
mixture of clay, silt, and sand-sized particles. |
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sand |
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sediment consisting of
particles 0.005-2.0 mm in diameter. |
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silt |
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same as sand. |
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bedrock |
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The continuous mass of
solid rock that makes up Earth’s crust. |
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cation exchange |
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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.
|
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conservation district |
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one of many county-based
entities created by the soil conservation service to promote practices that
conserve soil. |
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contour farming |
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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. |
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terracing |
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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. |
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crop rotation |
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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. |
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cropland |
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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. |
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desertification |
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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. |
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dust bowl |
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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. |
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erosion |
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the removal of material from one
place and its transport to another by the action of wind or water.
|
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fertilizer |
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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. |
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inorganic fertilizer |
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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. |
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organic fertilizer |
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a fertilizer made up of
natural materials (remains/wastes of organisms): animal manure, crop residues,
fresh vegetation, and compost. |
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green revolution |
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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.
|
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industrialized agriculture |
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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. |
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traditional agriculture |
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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. |
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subsistence agriculture |
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farming families produce
food for themselves. Intensive traditional agriculture, produce excess food to
sell at markets. No use of fossil fuels. |
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intercropping |
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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. |
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irrigation |
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the artificial provision of
water to support agriculture. Can lead to waterlogging and salinization. |
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leaching |
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the process by which solid materials such as minerals are dissolved in a liquid, usually water, and transported to another location. |
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monoculture |
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the uniform planting of a
single crop over a large area. Characterizes industrialized agriculture. |
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overgrazing |
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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.
|
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parent material |
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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.
|
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rangeland |
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or pasture, land used for grazing
livestock. One of the places where we get most of our food and fiber, like
croplands. |
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salinization |
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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. |
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shelterbelt |
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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. |
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topsoil |
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Portion of soil most
nutritious for plants and most direct importance to ecosystems and to
agriculture. Also known as the A-horizon. |
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waterlogging |
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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. |
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weathering |
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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.
|
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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.
|
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Low-Input Sustainable Agriculture Program |
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provides funding for individual farmers to develop and practice
sustainable agriculture. |
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Food and Agriculture Organization (FAO)- |
|
Internationally, the U.S. promotes soil conservation and sustainable
agriculture through this. |
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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. |
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