Mastering Enviro Science 7

Front 1

What has been the trend in crop diversity over the past century?

Back 1

We have lost a lot of genetic diversity in plants. in the US, fruit and vegetable crops have decreased in diversity by 90% in less than one century.

Front 2

Soil forms slowly and is a complex system. When decomposers break down organic molecules, they contribute a dark, spongy, an organic material to soil composition called?

Back 2

Humus

Front 3

Erosion usually begins when____.

Back 3

The vegetation is removed either naturally or by humans

Front 4

over irrigation in dry areas can cause ____.

Back 4

A buildup of salt in the soil to the point where it negatively affects plant growth.

Front 5

What is the idea that one should not undertake new actions until ramifications of the action is well understood?

Back 5

Precautionary principle

Front 6

What are effects of over nutrition?

Back 6

Chronic over nutrition can lead to diabetes and cardiovascular disease.

Front 7

What is malnutrition?

Back 7

Occurs in people who consume adequate calories but lack essential nutrients, such as vitamins and minerals.

Front 8

What is kwashiorkor?

Back 8

Occurs in people whose diets include ample calories but very low levels of essential amino acids and proteins.

Front 9

What is under nutrition?

Back 9

People who regularly lack access to sufficient food calories.

Front 10

What is marasmus?

Back 10

Inadequate caloric intake coupled with protein deficiency.

Front 11

What are some characteristics of traditional agriculture?

Back 11

- Many crops grown together on small plots of land

- Relies on human and animal power

- Controls pests with natural pesticides and planting of multiple crops

Front 12

What are some characteristics of industrial agriculture?

Back 12

- Controls pests with synthetic pesticides

- Heavy use of synthetic fertilizer

- Relies on fossil fuel powered machinery

- Single crops grown on large plots of land

Front 13

What is organic litter?

Back 13

This layer consists of plant residue atop the soil surface. on a forest floor, it may be leaves and twigs. in a field, it may be crop residue left after harvest.

Front 14

What is topsoil?

Back 14

This layer consists of organic matter, humus, and inorganic minerals. it facilitates plant rooting, has high nutrient content, and holds water.

Front 15

What is the eluviated layer?

Back 15

This layer loses minerals and organic matter to the layer beneath it.

Front 16

What is subsoil?

Back 16

This layer accumulates minerals and organic matter leached from upper soil layers.

Front 17

What is Parent material?

Back 17

This layer forms that base geologic material in a particular location; it is sometimes called bed rock.

Front 18

What is conservation tillage?

Back 18

Farming practices that minimize disturbance to soil.

Front 19

What is inter cropping?

Back 19

The practice of planting different crops in strategic arrangements within the same field.

Front 20

What is crop rotation?

Back 20

Alternating the crops grown on a field from one season to the next.

Front 21

What are shelter belts?

Back 21

Rows of trees or other tall plants grown at edges of farm fields in order to slow down winds.

Front 22

What is contour farming?

Back 22

Tilling sideways across a hillside to slow water running down the slope.

Front 23

What is terracing?

Back 23

Creates level platforms for crops on steep hillsides in order to hold rainwater and reduce soil erosion.

Front 24

Why is variety in crop plants important for "food security"?

Back 24

Varieties contain genes that, through conservational breeding, might confer residence to disease.

Front 25

How does the conservaton reserve program (CRP) try to protect soil for future agriculture?

Back 25

The CRP pays farmers NOT to grow crops on land that is not very well suited for crop production.

Front 26

Which of the following statements best describes the benefits of using organic fertilizers, also known as "green manures", such as dead plants?

Back 26

Organic fertilizers increased humus in soils.

Front 27

Over time, pesticides become less effective. This is because ____.

Back 27

Pest can evolve defense against pesticides.

Front 28

In regards to energy efficiency, aquaculture is ____.

Back 28

Incredibly energy efficient compared to harvesting fish from open waters.