Question 1

What is the agent of most soil erosion?

Accepted Answer

Moving water, such as rivers and streams, is the most common agent of soil erosion, as it carries away soil particles and deposits them downstream. Wind and earthquakes can also contribute to soil erosion, but are not as significant as moving water. Excess heat does not directly cause soil erosion.

Question 2

Which statement best describes salinization?

Accepted Answer

Salinization occurs when irrigation water contains dissolved salts that accumulate in the soil over time, leading to reduced soil fertility and decreased crop yields. It is a result of repeated applications of irrigation water to the soil. It is not a desirable outcome and can have negative impacts on agricultural productivity and the environment.

Question 3

What is representative of the conservation tillage approach?

Accepted Answer

The statement "It is used on 72% of Canada's cropland" represents the conservation tillage approach.

Question 4

Which statement best describes the effects of conservation tillage compared to conventional tillage?

Accepted Answer

Conservation tillage reduces fuel and tillage costs compared to conventional tillage. It also helps to preserve soil structure and prevent erosion. However, it may require increased use of herbicides to control weeds. Conservation tillage does not accelerate water loss from the soil, nor does it cause soil compaction.

Question 5

What is one outcome of conservation tillage?

Accepted Answer

Conservation tillage helps to reduce erosion by leaving crop residues on the soil surface which protects the soil from the damaging effects of wind and water erosion.

Question 6

Which term best applies to a farm where several varieties of wheat are growing?

Accepted Answer

Polyvarietal cultivation refers to the practice of growing multiple varieties of crops together in a single field. In this case, several varieties of wheat are being grown together, making polyvarietal cultivation the appropriate term. Intercropping involves growing multiple crops in the same field simultaneously, whereas agroforestry involves integrating trees into farming systems. Monoculture refers to the practice of growing a single crop in a given area.

Question 7

What is one possible result of salt build-up?

Accepted Answer

Salt build-up can lead to soil salinization, making the land agriculturally unproductive as the salt content can inhibit plant growth and reduce crop yields.

Question 8

A relationship between poverty and soil erosion occurs in many developing countries.The plowing of marginal land by poor farmers leads to soil erosion,land degradation,and thus to further poverty.What type of cycle is this?

Accepted Answer

This is a destructive positive feedback cycle as poverty leads to soil erosion and land degradation which in turn contributes to further poverty. It is a positive feedback cycle because the effects of poverty and soil erosion amplify each other, leading to further degradation of land and deepening poverty.

Question 9

A garden plot contains ten species that mature at different times.Some species are used for food,fuel,or medicine.Some take nutrients from the soil,and some return nutrients to the soil.Which term best describes the garden plot?

Accepted Answer

The garden plot contains ten species that have different functions and mature at different times, indicating that it is a polyculture.

Question 10

On what percentage of the world's croplands is topsoil eroding faster than it forms?

Accepted Answer

According to the Food and Agriculture Organization (FAO), about 38% of the world's croplands are experiencing topsoil erosion at a rate that is faster than it can form. This is a significant environmental issue as topsoil is vital for food production and maintaining healthy ecosystems.

Question 11

Which agricultural style prevents erosion on steep slopes?

Accepted Answer

Terracing involves creating steps on steep slopes, which helps to slow down runoff water, reduce erosion and nutrient loss. This method has been used for centuries across the world in different forms, and is highly effective in preventing soil erosion on steep slopes.

Question 12

What percentage of cultivated land in the Canadian prairies is affected by wind erosion?

Accepted Answer

About 36% of cultivated land in the Canadian prairies is affected by wind erosion.

Question 13

What is the term for plowing,breaking up,and smoothing the soil in the autumn in order to facilitate planting in the spring?

Accepted Answer

Conventional tillage involves plowing, breaking up, and smoothing the soil in preparation for planting. This is typically done in the fall to allow the soil to settle and break down over the winter months, which facilitates planting in the spring. Conservation tillage, terracing, and contour farming are all different methods of soil management that aim to reduce soil erosion and improve soil health, but do not necessarily involve the same level of soil disturbance as conventional tillage.

Question 14

When is a person considered undernourished?

Accepted Answer

Undernourishment is a condition that arises due to the lack of essential nutrients in the body. It occurs when a person consumes fewer than the basic minimum number of daily calories required to sustain healthy body weight and functions. Options A, B, and D are incorrect because mere meat deficiency or poor food quality, or excessive junk food consumption may not necessarily result in undernourishment.

Question 15

Which activity is involved in contour farming?

Accepted Answer

Contour farming involves plowing and planting across the natural contours of the land, rather than up and down slopes. This method reduces soil erosion by slowing water runoff.

Question 16

Which statement best describes alley cropping?

Accepted Answer

Alley cropping involves planting crops between hedgerows of trees or shrubs that are either fruit bearing or used for fuelwood. This helps to reduce soil erosion, improve soil fertility, and provide additional sources of income through the sale of the tree or shrub products. It is a common agroforestry practice used in sustainable agriculture. Options A, B, and C describe other farming practices such as no-till farming, contour plowing, and terracing respectively.

Question 17

Which term is used to describe the planting of crops in alternating rows of close-growing plants?

Accepted Answer

Alley cropping involves planting rows of trees or shrubs to create alleys within which crops are cultivated. This method can improve soil fertility and reduce erosion.

Question 18

Which practice both reduces erosion and  prevents the spread of pests and plant diseases?

Accepted Answer

Strip cropping involves planting different crops in alternating strips, which helps to reduce erosion by preventing runoff and improve soil health. It also helps to prevent the spread of pests and plant diseases since different crops can deter different pests and diseases. Contour farming also helps reduce erosion, but it may not necessarily prevent the spread of pests and plant diseases. Row cropping and terracing do not necessarily prevent erosion or the spread of pests and diseases.

Question 19

What is the greatest source of water pollution?

Accepted Answer

Sediment from erosion is the greatest source of water pollution because it can cloud waterways, reducing the amount of sunlight reaching aquatic plants, clogging fish gills, and altering the ecosystem by smothering aquatic habitats.

Question 20

What is one possible result of irrigation?

Accepted Answer

Irrigation can lead to waterlogging of the soil, as excessive water can accumulate and saturate the soil, reducing air spaces and affecting plant roots and soil biota negatively.

Quiz 14: Food and Soil Resources