GEOS Ch10
according to the united states department pf agriculture (USDA), the term "organic" means
at least 95% of the ingredients are organic
which of the following are examples of ways to reduce tillage on farms to control soil erosion directly plant seeds through mulch or ground cover
cultivating the land on a less frequent basis the use of chisel plow or a coulter for planting
Soil fauna, such as bacteria, algae, and fungi are important to soil health because they...
decompose and recycle leaf litter, releasing nutrients back in the soil for plant use
crop residues are left on farm fields after harvesting in order to____.
protect soil from erosion
one advantage of using organophosphate pesticides to destroy pests is that the chemicals break down_____. however, farm workers are often sent into fields too soon after spraying and are exposed to this lethal fertilizer.
quickly
using polyculture feels and adjusting the timing of planting to avoid major pest outbreaks are two common practices associated with ______ agriculture
sustainable
The act of shaping the land surface to create level shelves of earth for agriculture is known as
terracing
Soil ________ refers to the proportion of sand silt and clay
texture
the process of _______ saturates soil with water and can cause root death due to a lack of oxygen
water logging
In the United States, DDT was banned in the 1960s because
the pesticide was found to negatively affect wildlife
______ crops are special fields designed to attract pests away from other plants. eventually these fields are heavily sprayed with pesticides to kill off pests before they can escape.
trap
as pesticide resistant pests continually evolve, there is an ever-increasing need for newer, better types of pesticides. This cycle is known as the pesticide
treadmill
building a few millimeters of soil can take anywhere from a few _____ (in a healthy grassland) to a few _____ ( in a desert or tundra).
years thousand years
true or false: once soul nutrients are depleted, they cannot be replenished
false
The major components of soil are
1.water
around the world, about _____ of earths surface is threatened by desertification, or conversion of productive lands to desert
1/3
The soil layer that is rich is organic matter and from which most of your food is grown is called the _____ horizon
A
the ______ horizon is just above the parent material and as such, primarily consists of weathered rock fragments
C
the pesticide commonly known by only 3 letters ________ was mass produced during WW2 and quickly adopted by farmers afterwards, being applied to crops, houses, livestock and even people
DDT
pest resurgence often occurs when _____
a few individuals of a population survive pesticide treatment and lead to the propagation of new pesticide resistant populations
which if the following statements accurately describes how environmental factors affect soil development
a lack of rainfall can stress soil fauna steep topography increases soil erosion by water in extremely cold environments soil fauna recycle nutrients very slowly
fumigants are_____
a type of pesticide that is usually delivered in the form of a gas commonly applied to strawberries and other low-growing crops extremely dangerous to humans
farm policies, especially price supports for ethanol production, often result in farmers
abandoning soil-conservation practices such as contour plowing
which of these animals began to disappear from their former habitat as a result of widespread use of the pesticide DDT in their environment
bald eagles brown pelicans peregrine falcons
wasps, ladybugs, ducks, geese and even some plant species can be utilized as a form of ______ pest control, which involves living organisms that are used to control pest populations.
biological
integrated pest management(IPM) is a type of agriculture that relied upon _____ and _____.
careful monitoring of pest populations, mechanical techniques such as crop trapping
silt and ______ are extremely small mineral particles in soil that are sticky and hold water because of their flat surfaces and ionic charges
clay
numerous environmental conditions such as ____, topography, and _____ can affect the health of the soil ecosystem
climate, parent minerals
cover crops such as ______ can be planted after a harvest to help protect soil from erosion
clover alfalfa rye
chlorinated hydrocarbons can resist in the soil for _____ and are stored in the fatty tissue of organisms so they become concentrated in the food chain
decades
the conversion of productive land to desert, and the blowing of sand out of drylands and deserts to other places is defined as _____
desertification
POPs are ______
easily absorbed into fatty tissues organic pollutants stable
as reflected by the fact that the average food product in the US travels over 2,000km from farm to table, food processing and distributions also are ______-intensive in regards to fossil fuels
energy
every year, about 3 million hectares of cropland are made unusual by this process, which takes soil away from the surface via wind and water
erosion
the overuse of ___ often degrades water quality by introducing excess nutrients to the environment, and can lead to human health problems such as "baby blue syndrome"
fertilizers
people have used used chemicals to control agricultural pests
for thousands of years
the pesticide type known as _______ can be delivered in the form of a gas that readily penetrates the soil. They are very dangerous to humans and are restricted or banned in many areas.
fumigants
_________ pesticides are broad spectrum poisons made up of toxic elements such as arsenic sulfur, copper and mercury
inorganic
there are different types of pesticides depending on the pest: ______ kill insects and _____ kill fungi, specifically
insecticides fungicides
planting multiple crops in the same field, known as ______, helps protect soil from nutrient loss and erosion while also providing multiple harvests per field
interplanting
clays that are rich in the element _____ give tropical souls, such as those of Brazil, a reddish hue.
iron
the largest single use of freshwater withdrawal in the world is for
irrigation
which of the following statements regarding health problems associated with pesticides are true
millions of people worldwide are affected pesticides can cause both short term (acute) and long term (chronic) problems most of the illnesses occur in people in developing countries
What type of climate is linked to the best agricultural land?
moderate
the most dominant soil types in the farming regions of the United States are ___
mollisols alfisols
some farmers choose to pass off foods grown with pesticides as more valuable ______ produce in order to tap into its $11 billion market share
organic
the majority of recent agricultural growth is the result of _______
new crop varieties and the increased use of fertilizers, pesticides and irrigation
soil that is rich in _____ is black in color, soft and workable, and full of nutrients
organic matter
the pesticides classed as _____ are extremely effective against agricultural pests, but in turn cause harm to workers who are sent into fields soon after spraying
organophosphates
chlorinated hydrocarbons are found in the fatty tissues of animals and humans living in locations far from the source where they were first used because they
persist for years move readily through water and air
_____ organic pollutants(POPs) are pesticides that are highly toxic, do not break down easily, and are easily absorbed into fatty tissues
persistent
the loss of beneficial insects, those that keep pest populations down, has been attributes to
pesticide use
_______ include a variety of pest-killing chemicals such as herbicides, fungicides and insecticides
pesticides
human health effects such as cancer, birth defects, parkinson disease, and immunological problems may be caused by chronic exposure to
pesticides
how does crop rotation help keep pest populations in control?
pests are crop specific, so their populations cannot keep increasing
Contour plowing is
plowing across a hillside, rather than up and down one of the primary methods to reduce soil erosion
salinization is caused by the accumulation of mineral ______ in the soil
salt
practices such as contour plowing, the creation of windbreaks, and the protection of grass-lined waterways will reduce______
soil erosion
mycorrhizal symbiosis is a _____.
special symbiotic relationship between plants and a species of soil fungi
which of the following correctly describe recent trends in the amount of arable land?
the amount worldwide has decreased the amount in the US has decreased
important nutrients for plant growth, such as nitrogen and phosphorus, are added to the soil by
the application of fertilizers
farmers that use chisel plows and coulters or those who choose to cultivate their fields less frequently are actively engaging in reduced ______ practices that leave crop residue on fields to minimize soil erosion
tillage
which of the following are examples of sustainable farming practices?
timing planting or cultivation of crops to avoid pest outbreaks restoring windbreaks, hedgerows and ground cover around watercourses using polyculture fields that grown many different types of crops together
true or false: modern farming is an energy-intensive process that uses fossil fuels for both fuel and fertilizers
true
DDT in the environment was particularly terrible for large bird species as it acted as an endocrine dis rupture resulting in ____
very thin eggshells