Deck 11: Soil: Foundation for Land Ecosystems

Question 1

The Dust Bowl experience of the United States in the 1930s was caused primarily by

A)planting grains in soils that could only support leaf crops sustainably.
B)lack of any soil conservation practices,continuous cropping,coupled with natural drought.
C)lack of enforcement of the soil conservation provisions of the 1862 Homestead Act.
D)attempts to farm areas with desertlike climate and thin topsoil.

Answer 1

lack of any soil conservation practices,continuous cropping,coupled with natural drought.

Question 2

Which of the following is true?

A)Only about 10% of the world's food comes from land-based agriculture.
B)Soil degradation is a problem unique to the past two centuries.
C)More than 20% of cultivated land was degraded between 1989 and 2003.
D)The Mayan Empire serves as a model for excellent soil management.

Answer 2

More than 20% of cultivated land was degraded between 1989 and 2003.

Question 3

The very deep roots of many prairie plants that have decomposed over thousands of years have contributed to the high fertility of the

A)C horizon of alfisols.
B)A horizon of molisols.
C)B horizon of aridisols.
D)C horizon of molisols.

Answer 3

A horizon of molisols.

Question 4

Soils with the greatest water-holding capacity tend to have

A)poor aeration and lowest workability.
B)poor nutrient-holding capacity and good workability.
C)good water infiltration and workability.
D)good aeration and poor workability.

Question 5

The main lesson learned from the experiences of Gabino Lopez farming steep lands in Guatemala is that

A)the application of modern agricultural techniques can greatly increase crop production and sustainability.
B)modern agricultural equipment permitting deep plowing can greatly increase crop production and sustainability.
C)the widespread use of pesticides and herbicides can greatly increase crop production and sustainability.
D)many crops traditionally raised by native people depend too much on the application of pesticides.

Question 6

One at a time,you test how quickly each of the following substances will settle out of water.To measure this property,you separately test each of the following by placing 100 grams of the substance and 500 milliliters of water into a 1 liter jar and screw on the lid tightly.Then you shake the jar violently for 1 minute and set the jar down.Which one of the following would settle the fastest,creating the clearest water in the fastest amount of time?

A)gravel
B)clay
C)silt
D)sand

Question 7

Based upon soil particle size,the largest to smallest are

A)sand,silt,and clay.
B)sand,clay,and silt.
C)clay,sand,and silt.
D)silt,sand,and clay.

Question 8

Severe wildfires followed by heavy rains have significantly eroded the soil of a formerly forested region.Which one of the following horizons is most likely intact with little disturbance?

A)A horizon
B)O horizon
C)E horizon
D)C horizon

Question 9

A hydric soil is one that

A)is typical of wetlands and may contain peat.
B)is unusually well suited for agriculture.
C)is typical of tropical areas that receive abundant rainfall.
D)was typical of the U.S.prairie states until the Dust Bowl of the 1930s.

Question 10

Detritus feeders and decomposers are most likely found in the

A)E and B horizon.
B)A and O horizon.
C)B and C horizon.
D)C and E horizon.

Question 11

A soil is found to have 50% sand,30% silt,and 20% clay.This soil would be referred to as

A)silty.
B)sandy.
C)clayey.
D)loamy.

Question 12

Which one of the following soil orders is the most typical of drylands and deserts?

A)alfisols
B)oxisols
C)mollisols
D)aridisols

Question 13

The dust storm in Arizona in 2011

A)originated in Mexico and moved north into Arizona.
B)occurred during a period of unusually heavy rainfall.
C)was the result of loss of soil microorganisms.
D)was triggered by drought conditions similar to those of the 1930s Dust Bowl.

Question 14

Within soil,a natural cycle of

A)decomposers break down detritus to release nutrients used by producers.
B)detritus breaks down decomposers to release nutrients used by producers.
C)decomposers break down nutrients to release detritus used by producers.
D)decomposers break down detritus to release nutrients used by consumers.

Question 15

Which one of the following soil types will hold the most water? The most water would be held by a soil consisting of equal masses of

A)sand and silt.
B)clay and sand.
C)silt and clay.
D)small stones and sand.

Question 16

Agricultural sustainability depends upon an understanding and proper management of the cornerstone of food production,

A)irrigation systems.
B)agricultural soils.
C)the generation of new plant hybrids using genetic engineering.
D)the agricultural technology necessary to plow,plant,and harvest.

Question 17

Where there is rapid decomposition of plant matter,we expect to find soils that have

A)a very thin O horizon.
B)a tremendous capacity to hold water.
C)a particularly thick C horizon.
D)high fertility and a very thick B horizon.

Question 18

According to GLASOD,the he main risk of continuing degradation of agricultural land is

A)an increasing need to rely upon irrigation.
B)declining agricultural productivity.
C)the need to shift from grain crops to soybeans.
D)the need to rely increasingly on herbicides and pesticides.

Question 19

Which one of the following soil horizons is least likely to be interacting directly with living organisms?

A)A horizon
B)O horizon
C)E horizon
D)C horizon

Question 20

After joining the Peace Corps,your assignment is to help spread good agricultural practices to people living in the humid tropics.After receiving training,you tell the local farmers to

A)use oxen or mules to deep plow and turn the soil to bring deep nutrients to the surface.
B)dig deeper wells to bring up water reserves that will triple the productivity of their fields.
C)start a water catchment,apply manure and mulch to their fields and avoid tilling the soil if possible.
D)shift to crops such as rice,which are more resistant to the natural pests and parasites.

Question 21

Compaction of soil in a garden harms plants by

A)increasing aeration,decreasing infiltration,and increasing runoff.
B)decreasing aeration,decreasing infiltration,and increasing runoff.
C)increasing aeration,increasing infiltration,and decreasing runoff.
D)decreasing aeration,increasing infiltration,and decreasing runoff.

Question 22

We would expect that soil leaching would be most severe in regions where

A)there is little rainfall and no irrigation of crops.
B)irrigation is applied to fields on hillsides.
C)mollisols are abundant and farmers rarely plow.
D)cattle are grazed and natural grasses cover the land.

Question 23

In which of the following agricultural situations are fertilizers least needed?

A)A pumpkin patch is harvested only in the fall,and the vines remain behind.
B)1,000 acres of corn are raised and harvested for export from a midwestern farm.
C)A natural prairie pasture where cattle feed and defecate.
D)A field where a farmer applies cow manure after harvesting hay.

Question 24

Farmers often appreciate a long,light rain over main hours after a long drought,instead of a sudden downpour.This is because a long,light rain permits better

A)infiltration.
B)water-holding capacity.
C)transpiration.
D)soil fertility.

Question 25

Which of the following farming practices would be expected to produce the least nutrient leaching,and thus contribute most to soil sustainability?

A)deep plowing,irrigation,and the use of inorganic fertilizers
B)deep plowing,no irrigation,and the use of inorganic fertilizers
C)no plowing,irrigation,and the use of organic fertilizers
D)no plowing,no irrigation,and the use of organic fertilizers

Question 26

The use of biochar (charcoal)incorporated into soil structure

A)may be a way to lower atmospheric carbon levels because biochar decays very slowly.
B)has been found to accelerate global climate change.
C)contributes to soil fires which increases the rate of soil degradation.
D)greatly decreases soil fertility.

Question 27

Some farmers near an ocean must irrigate their soybean crops to have any success.Desperate and without a source of fresh water,one of them decides to irrigate his field with seawater.The other farmer captures rain in special traps and lightly irrigates his crops.What would we expect are the results of these different forms of irrigation?

A)The seawater irrigation plants produce many beans while the light irrigation produces few beans.
B)The seawater irrigation kills the plants while the light irrigation produces few beans.
C)Both forms of irrigation produce good crops with moderate production of beans.
D)The seawater crops last longer than the fresh water crops,but only the seawater crops produce beans.

Question 28

The movement of the water through this plant involves

A)transpiration and stomata in the leaves.
B)transpiration and stomata in the roots.
C)infiltration and high soil fertility.
D)infiltration and photosynthesis in the leaves.

Question 29

Most plants acquire their minerals from

A)the recycling of nutrients from detritus.
B)the precipitation of minerals from rainfall.
C)the weathering of rock.
D)dust storms that transport minerals into a region.

Question 30

On a hot day with bright sunlight and plenty of water in the soil,a plant actively engaged in photosynthesis will use its stomata to move

A)water and oxygen from the plant and take in carbon dioxide.
B)water and carbon dioxide from the plant and take in oxygen.
C)oxygen and carbon dioxide from the plant and take in water.
D)water from the plant and take in carbon dioxide and oxygen.

Question 31

The detritus food web illustrated in the lower right of this diagram primarily occurs in the

A)E horizon.
B)O horizon.
C)B horizon.
D)C horizon.

Question 32

Silts and loams are the best soil textures for plant growth because they have

A)only moderate soil constraints.
B)moderate infiltration but low aeration.
C)moderate aeration but low infiltration.
D)poor infiltration and aeration.

Question 33

Most plants do best in soils with a pH that is

A)below 2.
B)between 6-8.
C)between 8-10.
D)above 10.

Question 34

When a plant does not get enough water and starts to wilt,it

A)opens its stomata,stops transpiration,and generates oxygen but not carbon dioxide.
B)opens its stomata,starts transpiration,and generates carbon dioxide but not oxygen.
C)closes its stomata,stops transpiration,and no longer brings in carbon dioxide from the air.
D)closes its stomata,starts transpiration,and no longer brings in oxygen from the air.

Question 35

Which of the following would be best suited for planting crops such as corn or wheat?

A)an irrigated aridisol
B)a fertilized alfisol
C)a plowed oxisol
D)an irrigated gelisol

Question 36

This figure reveals

A)just two soil horizons.
B)a soil profile.
C)soil leaching.
D)five soil orders.

Question 37

Compared to inorganic fertilizers,organic fertilizers such as

A)cow manure applied to a field increase the chances of nutrient leaching.
B)cow manure applied to a field reduce the chances of nutrient leaching.
C)liquid ammonia sprayed on a field decrease the chances of nutrient leaching.
D)liquid ammonia sprayed on a field increase the formation of humus.

Question 38

Which of the following would be classified as "soil constraints"?

A)cold climate
B)moderate to heavy rainfall
C)poor drainage,salinity and high levels of aluminum
D)low erosion potential and high levels of phosphorus

Question 39

Children learning the process of good home gardening decide to help as best they can.Every day they walk along rows of bean plants,carefully inspecting each plant for insects,and removing any that they find.However,the bean plants do not grow well,and few beans form.Their parents notice the poor beans,inspect the plants and soil,and tell the children that walking around the plants every day has hurt the plants by

A)compacting the soil,decreasing aeration and infiltration.
B)increasing soil aeration and killing soil microorganisms.
C)reducing the nutrient minerals out of the soil.
D)converting the topsoil into clay.

Question 40

Walking along the woods,you spot a lizard that quickly runs under some leaves resting on the forest floor.Looking under the leaves to find the lizard,you notice that the soil is very moist despite several days without rain.This moist soil layer just under the leaves is a result of

A)humus with a high water-holding capacity and reduced evaporative loss in the O horizon.
B)sand with a high water-holding capacity with water supplied from the B and E horizon.
C)low infiltration and high evaporative loss in the B horizon.
D)a low water-holding capacity of the lower soil layers and high evaporation through the top soil layers.

Question 41

Which of the following represents the proper sequence of these types of erosion,resulting from rainfall?

A)Gully erosion leads to splash erosion that contributes sheet erosion.
B)Sheet erosion leads to gully erosion that contributes splash erosion.
C)Sheet erosion leads to splash erosion that contributes to gully erosion.
D)Splash erosion leads to sheet erosion that contributes to gully erosion.

Question 42

In a healthy soil environment that demonstrates sustainability,

A)the levels of humus steadily declines,but the aeration increases.
B)sandy or silty soils are steadily converted to clay soils.
C)abundant populations of bacteria are steadily replaced by mycorrhizae.
D)the humus forming processes of topsoil is renewed by the addition of detritus and humus.

Question 43

A soil that has become mineralized will have

A)more earthworms,more humus,and more sand.
B)fewer earthworms,less humus,and more sand,silt,or clay.
C)more detritus,more fungi,but less aeration.
D)more detritus,more bacteria,but less water-holding capacity.

Question 44

Global satellite imagery of land on Earth over the past 20 years reveals

A)a net improvement of the quality and area of cropland.
B)a net decline in the overall quality of cropland.
C)the loss of more than 5% of land to the construction of new lakes and dams for electrical generation.
D)a loss of more than 7% of land mass due to rising ocean levels.

Question 45

Erosion can result in a vicious cycle of worsening erosion because

A)rainwater increasingly soaks into the ground.
B)the accumulation of humus makes erosion more likely.
C)plants are less likely to grow in an eroded region.
D)the pH of the soil increases as erosion continues.

Question 46

The main cause of desertification by the degradation of drylands is

A)human activities.
B)global increases in temperature.
C)shifting weather patterns.
D)destruction of the ozone layer.

Question 47

Most plant productivity in a forest is most directly related to the

A)intensity of sunlight reaching the forest floor.
B)unvarying temperatures throughout the year.
C)consistent precipitation in every month of the year.
D)quality of topsoil in the forest.

Question 48

The sustainability of agricultural practices

A)decreases if the soil is degraded by erosion or salination.
B)requires that the soil be plowed at least three times annually.
C)increases if the field is irrigated in amounts equal to the total annual rainfall.
D)requires the presence of soil nematodes.

Question 49

Desertification is

A)a natural process of succession that cycles from deserts to prairies to forests to deserts.
B)the formation of dryland ecosystems in regions where temperatures have increased.
C)the natural movement of deserts advancing into new regions due to shifts in wind direction.
D)often the result of topsoil erosion leading to a permanent reduction in productivity.

Question 50

Adding humus in a garden will most likely

A)decrease the nutrients of the soil and the water-holding capacity.
B)increase the nutrients of the soil and the water-holding capacity.
C)increase the nutrients of the soil but decrease the water-holding capacity.
D)decrease the nutrients of the soil but increase the water-holding capacity.

Question 51

The soil structure resulting from the castings of earthworms

A)improves the infiltration and aeration of soil.
B)decreases the infiltration and aeration of soil.
C)decreases the nutrient-holding capacity of soil.
D)improves the nutrient-holding capacity but decreases the aeration of soil.

Question 52

At a county fair,the winner of the best garden vegetable competition is asked how she grows such wonderful produce consistently.Wanting not to reveal all of her secrets,she says she uses composted materials.What this gardener is using is

A)a type of soil made of sand and fertilizer.
B)a type of soil made of a mixture of clay and sand.
C)decomposed organic matter called humus.
D)a mixture of fungi,insects,and worms.

Question 53

Mycorrhizae are

A)pathogenic soil bacteria and fungi that destroy plant roots.
B)common in soils that lack a functional humus.
C)symbiotic fungi that increase soil nutrient uptake in plant roots.
D)important soil millipedes that increase aeration of topsoil.

Question 54

Hardened soils that have minimal infiltration and aeration may form cryptogamic crusts

A)consisting of algae,lichens,and mosses that stabilize the soil surface.
B)consisting of algae,lichens,and mosses that continue to erode the soil surface.
C)characterized by large stones and gravel called desert pavement.
D)representing accumulations of salts that prevent plant and fungal growth at the soil surface.

Question 55

The greatest cause of topsoil loss around the world is

A)erosion.
B)the construction of new buildings and roads.
C)the creation of new mines.
D)rising ocean levels.

Question 56

You construct a home in a hilly forested region in Wisconsin.Which of the following would most likely result in the least amount of soil erosion from the surrounding forested hillsides?

A)leave most of the forested region alone,in its natural state,and plant a few ornamental trees
B)clear all plants from the property and plow the soil
C)clear all plants from the hillside and plant garden crops such as cabbage and tomatoes and create a few small flower beds
D)keep the trees in place but clear all of the other vegetation and then rake the soil leaving it bare and unplowed

Question 57

Which of the following would do the most harm to the productivity of a garden?

A)killing the fungi and bacteria in the soil
B)killing the nematodes and insects in the soil
C)adding humus and sandy loam to the soil
D)plowing into the soil the stalks from last year's crops

Question 58

Which of the following might best help grasses in a lawn that have been growing in a soil that has a high percentage of clay?

A)adding fertilizer in the spring and fall
B)adding lime in the spring to neutralize the pH of the soil
C)aerating the lawn by removing small plugs of soil
D)watering the lawn about an inch of water every other day

Question 59

Which of the following would most reduce the productivity of a 10-acre forest?

A)paving a 2-lane dirt road through the forest
B)removing the topsoil from the forest
C)cutting down the largest trees in the forest
D)adding millions of earthworms to the forest soil

Question 60

Passing along some old gardening advice,a neighbor says,"If you want a great garden,

A)keep the fungi and earthworms happy."
B)water deeply every day."
C)add at least 3 inches of sand and gravel to the soil every year."
D)use plenty of pesticides."

Question 61

The equipment in this photograph is used to minimize erosion.This equipment is used

A)to create shelterbelts and chemically fertilize the soil.
B)to plow the soil,plant seeds and create strip cropping in one operation.
C)for no-till planting.
D)for contour strip farming.

Question 62

Sustainable soil conservation requires

A)that developing countries maximize short-term strategies for immediate benefits.
B)long-term effective farming practices by individual landowners and also sound public policy.
C)individuals to work for the immediate benefit of their particular interests.
D)an understanding of the natural ability of soils to recover quickly from degradation.

Question 63

Planting rows of trees or shrubs around the periphery of a plowed field are long established farming practices that

A)serve as water reserves in times of drought.
B)attract insect pests away from the crops.
C)increase wind erosion and decrease soil moisture.
D)decrease wind erosion and increase soil moisture.

Question 64

In a region of eastern Washington state known as the Palouse,farmers grow wheat on steep sloped hills.Which of the following agricultural practices might be of greatest benefit in this region?

A)use of shelterbelts
B)contour strip farming
C)irrigation
D)repeated plowing

Question 65

Over the last one hundred years in the United States,

A)soil erosion has steadily increased while wind erosion has steadily decreased.
B)estimates and actual measurements indicate that soil erosion has decreased.
C)the increased reliance on plowing and technology has increased soil and wind erosion.
D)measurements of the amount of soil in major rivers indicate great increases in soil erosion.

Question 66

The strips of farmland in this region are used to

A)reduce wind erosion.
B)reduce water erosion.
C)irrigate the fields.
D)confuse insect pests.

Question 67

Irrigation can result in the salinization of soils because

A)shortages of freshwater require the use of saltwater for irrigation.
B)salts are deposited on the soil surface as water evaporates.
C)the irrigation water washes away soil leaving behind concentrated salts.
D)many of the plants grown in these regions excrete salts into the soil.

Question 68

Leaching of minerals from soils,especially calcium,magnesium and potassium can be increased when

A)the pH is lowered,especially from acid rain.
B)salty irrigation water is used to flush out polluted soils.
C)anti-microbial agents and nanoparticles contaminate soils.
D)excess chemical fertilizer is used over many years.

Question 69

Which one of the following would cause the greatest soil erosion to a forested hillside?

A)removing the dead trees
B)cutting down and removing all of the trees
C)converting the hillside from forest to grass
D)planting new trees in the forest

Question 70

A farm field that has used only inorganic fertilizer for the past 20 years is most likely to have

A)fewer soil organisms and less soil structure but increased nutrient holding capacity.
B)fewer soil organisms,less soil structure,and decreased nutrient holding capacity.
C)more soil organisms,more soil structure,and increased nutrient holding capacity.
D)more soil organisms,less soil structure,and decreased nutrient holding capacity.

Question 71

Overgrazing by cattle primarily contributes to desertification by

A)promoting erosion and loss of rooted plant cover.
B)contaminating streams with cattle wastes.
C)cattle outcompeting natural herbivores.
D)spreading the growth of non-native species.

Question 72

The planting of strips of trees and shrubs along the edges of plowed fields is used to

A)decrease wind erosion.
B)form water catchments for irrigation and wildlife conservation.
C)drain off excess water during heavy rainfall events.
D)limit the spread of crop pests.

Question 73

Desertification of North America's drylands is primarily the result of

A)plowing for crop production.
B)livestock grazing.
C)fires and the use of modern irrigation systems.
D)global climate change.

Question 74

No-till farming would be most beneficial for farmers

A)with steeply sloped fields.
B)who plant a cash crop every third year.
C)who typically experience minimal soil erosion.
D)using contour strip cropping.

Question 75

Global Assessment of Land Degradation and Improvement (GLADA)recently has started using satellite imagery to estimate above ground plant biomass.From this data we can describe

A)the types of soil below ground.
B)the amount of topsoil and the state of its microorganisms.
C)how much erosion and salination have occurred.
D)how land degradation and productivity change over time.

Question 76

The use of government rangelands for the grazing of cattle has

A)resulted in the increased productivity of these regions.
B)raised funds that are now available to replant these regions.
C)produced cooperative relationships between herders to sustainably manage these regions.
D)reduced productivity by at least 50% and lost the government money.

Question 77

The Kesterson Effect can result from efforts to restore land that are affected by

A)sewage contamination.
B)severe wind erosion.
C)severe water erosion.
D)salinization.

Question 78

Global soil erosion

A)increases the populations of aquatic organisms in streams and rivers.
B)adds soils to streams and rivers,which removes many pollutants.
C)pollutes rivers and oceans and reduces the refill rates of aquifers.
D)creates new ponds and lakes,which help to retain water in aquifers.

Question 79

Burkina Faso and the Keita project in Niger demonstrate that

A)corrective measures can successfully reverse soil degradation.
B)sustainable soil conservation efforts are impossible once soils are degraded.
C)despite human efforts,natural climate cycles may prevent sustainable practices.
D)desertification is a natural result of climate variation.

Question 80

Most reports of national erosion loss are based on

A)thousands of measurements of soil depth around the country.
B)measurements of the amount of soil suspended in the oceans and major rivers.
C)changes in the salinity and silt of the ocean where major rivers flush out to sea.
D)indirect measurements using maps,aerial photography,and precipitation data from land stations.