Growing population test

What are the layers of soil called?

Horizons

Which area of the world grows the most grain per unit of land area?

North America

How should soil be filled to preserve and enhance soil quality?

Soil should be conservatively tilled (Minimally), because it preserve the organic matter overtime and ultimately improves the soil quality which makes the plants stronger and healthier due to the rich topsoil

What type of soil is able to hold water and be less affected by drought?

Soil with more organic material (dark soil)

R horizon/ bedrock

The bedrock is below the C horizon and is a continuous layer of rock unlike the scattered rocks found in the C horizon

Bt corn

- an example of scientists incorporating disease and pest resistant genes directly into plants' genomes

Agricultural suitable land has a minimum average temperature of —

-4.5- 5.5 •C

chemical pesticides

-Effectively kill pests but are hazardous to the person doing the application - cause harm to non pest and beneficial insects in the plants and in the soil -pests can develop a resistance

Creation and Destruction of soil

-It takes a long time to make soil- rock has to be broken down by weathering and plant root actions, organic matter has to be broken down by microorganisms, and animals in the soil must mix the mineral and organic matter - contrastly, soil can be destroyed very quickly by events such as poor land use and erosion

What are the positive and negative consequences of turning forested land into farm land?

-More crops can be produced -increased food production -destroy habitats -destroys natural ecosystem

Erosion

-Process by which soil is depleted which leaves less soil for crops to grow - different terrains affect soil erosion rates

SRI

-Project that is working on increasing the productivity of rice and other crops by changing the management of plants, soil, water, and nutrients -rules: transplant rice plants early, leave them a lot of space, keep fields moist, add organic material to the soil

Land use is......

-The ways humans use the land that involves modifying and managing the natural environment; modifications include fields, pastures, industrial developments, golf courses, ski areas, parks, and roads - land use can affect the quality and availability of natural resources, such as soil,nutrients, plants, animals

Why is there plenty of food but people are still malnourished?

-distribution, poverty, etc - solution - GMO ex. Golden rice

mechanization of agriculture

-increase yields in North America - framing equipment/machinery is used but expensive as they are usually specialized for single crops

What are the positive and negative consequences of turning forested land into residential land?

-more houses are built - more homes to supply the growing population -pollution -destruction of native plants and animals

Agricultural pests

-pests decrease productivity but can be controlled with pesticides, insecticides, fungicides, and biological agents

topsoil

-the A and O layers make up the topsoil and is most important for plant growth and health -plants derive most of their nutrients from the topsoil -maintaining and improving the topsoil layer is important in maintaining and improving agricultural yields

Biological control methods

-use predatory insects to eat the crop pest -bacteria can fight infestation ex. Bt

On average how thick is the topsoil layer?

12 inches

How much of the land on Earth is used for agriculture?

33%

Agricultural suitable land has a minimum average rainfall of —

725-1475 mm

What is one of the most important land uses?

Agriculture

What crop would be good to plant after harvesting wheat?

Alfalfa, because it provides nitrogen to the soil which the wheat didn't so this crop would balance out the loss of nitrogen

soil quality is based on

Amount of nutrients, organic matter, and water that it can hold

What can cause a dip in the food production?

Bad weather or extreme drought

B horizon

Beneath the topsoil (O & A) also known as subsoil. Contains minerals and organic matter but is not as rich as the A horizon

What has allowed the farmers to produce enough food to feed the growing population?

Changes in farming practices, innovations in chemistry and biology, and careful management of the land

Which tillage strategy leaves more roots in the soil?

Conservative, because it made the soil healthier which made the roots healthier and able to live, whereas the intensive tilling dried up the soil and broke the roots

Which tillage strategy results in less erosion?

Conservative, because the soil is better held together by the roots and the stronger soil. Intensive tilling dries up the soil and kills the roots which increases the chance of erosion.

Inorganic fertilizers (synthetic)

Derived from minerals extracted from rocks

Which area of the world has been intensively used for the longest period of time?

Eurasia

What are the 3 things sustainable agriculture needs?

Fertile soils, adequate precipitation, and good growing temperatures

Monocropping

Growing the same crop on the same field year after year to save money on farming equipment - corn, wheat, soybeans are typical monocropping crops - growing the same crop year after year depletes the soil of some nutrients and allows pests to flourish leading to use of more pesticides

What does high quality farmland need?

High quality soil conditions --some areas are too dry to farm without irrigation and poor soils would need to be heavily fertilized in order to reach the same production levels as high quality soils

Which slope has the highest erosion rate?

Hilly terrain due to the steep slope

What is land used for?

Humans-Land for living on, producing food, recreation Natural users- life cycles,habitats—

How can erosion effect plant growth?

If topsoil is eroded away, plants can't succeed as they lack access to their needed nutrients

Why do plants in the wild thrive without fertilizer but many farms are required to use fertilizer to make their plants thrive?

In agricultural fields, plant matter is removed during the harvest and usually fields are a single type of plant that each need the exact same nutrients as the other plants around it

How much of the land in USA is high quality farmland?

Less than 20% due to increased development

C horizon

Lies below the B horizon; composed of parent rock ( rocks from which the soil is generated)

What do phosphorus fertilizers do?

Make nutrient poor soils healthy and can dramatically increase crop production

Which precipitation leads to good wheat growth?

Moderate precipitation provides the perfect amount of precipitation to yield tall and strong plants—

Why has agricultural land in the USA declined over the past 50 years?

More land has shifted towards urban uses and cropland/grazed forestland has been encroached upon in order to meet population demands and urban desires

What areas of the world are most suitable for agriculture?

Near water resources (North America, Africa, Europe, Asia)

What are the main nutrients provided by fertilizers?

Nitrogen, phosphorus, and potassium

Is agricultural land evenly distributed around the world?

No

Is all land equally useful for all purposes?

No

Will corn grow equally well in all agricultural areas?

No because each crop has different requirements and corn would not grow well in an agricultural area that did not suit corns temperature and conditional growing requirements

What are the 2 types of fertilizers?

Organic and inorganic (synthetic)

rotating crops

Planting different crops in the same field year after year and it meets the needs of different crops - discouraged pests due to constant changing food sources

Why are houses being built in farmland?

Population growth, housing needs, immigration/relocation, house market

Importance of potassium

Potassium is required for plant growth and is a common ingredient in fertilizers; the more fertility the soild has, the better the crop yield

What factors determine how well wheat grows?

Precipitation, slope of the land, climate

What is tillage?

Preparation of soil for planting that can include plowing, tilling, harrowing, and cultivating (mixing up of the soil)

What effect does vegetation have on erosion?

Protects soil from erosion because it holds the soil together

organic fertilizers

Provides nutrients and organic material that can help build up the topsoil

How do nutrients flow over time in plants?

Roots decay into organic matter which can be absorbed by the roots of new plants

Importance of roots and where to find them

Roots gather water and nutrients for plants and the root structure depends on the plant and soil structure - roots can be found in O, A, and B horizons

A horizon

Second layer of soil that is the surface soil containing mineral soil, decomposed organic material(humus) and many living organisms

With the population growth, has agricultural land grown? What about agricultural production?

The land that is suitable for agriculture has not grown, because productive farmland had been turned into residential land HOWEVER food production has kept pace with population growth and in some areas had exceeded its population growth

O horizon

Top most layer of soil that is composed of organic matter in relatively undecomposed form

What is arable land?

Used to grow annual crops Only 9% of Earth's land is arable due to the distribution of resources needed to grow crops

soil exhaustion

condition in which the soil becomes nearly useless for farming due to loss of nutrients