Gr. 9 Work Flashcards
What is soil erosion?
A naturally occurring process that affects all landforms. In agriculture, soil erosion refers to the wearing away of the field’s topsoil by the natural physical forces.
What is sustainable farming?
Farming that tries to sustain farmers, resources and communities by practicing methods that are profitable, environmentally sound and good for the community.
What is sustainable agriculture?
Agriculture that is economically viable (profitable), socially supportive (helps workers) and ecologically sound (preserves resources).
In what 4 ways can agricultural activities cause erosion?
Moving the topsoil in preparation for planting crops
Ploughing down steep slopes
Cutting down vegetation to farm
Grazing/ deforestation
What do we call areas where animals and farming equipment/ vehicles use the same accustomed pattern of movement?
Zones of compaction
Remember to do
The mining
What are glaciers?
Moving ice
How can glaciers cause erosion?
Abrasion and plucking
How does abrasion occur?
Rocks carried in the ice scrape the bedrock.
How does plucking occur?
Ice pulls off pieces of bedrock.
What 3 features can be found near glaciers?
Cirques
Arêtes
Horns
What is a cirque?
A bowl-like depression at the head of a glacier valley.
What is an arête?
A narrow ridge
What is a horn?
A peak in a pyramidal shape formed by cirques eroding 3 or more sides of a mountain.
What are drumlins?
Smooth, oval-shaped hills rising from till plains.
What is till?
Deposits of boulder clay or other sediments from a glacier.
What is moraine?
Till deposited along the edges of a glacier.
What 3 types of moraine do you get and what are they?
Terminal moraine-deposited at the end of
the glacier.
Lateral moraine-deposited in a thin line of
debris along the sides
Medial moraine-lateral moraines of two glaciers
merge.
What is a till plain?
A flat deposit of till where an ice sheet that separated from the glacier has melted.
What is an ecosystem?
A community of interacting organisms and their environment.
What is erosion?
The process whereby weathered rock pieces and soil are moved from one place to another.
What is food security?
A country produces enough products to export them, and then uses the income to import the products it needs.
Non-renewable resources
Natural resources that can’t be reproduced, grown or regenerated, and that can run out.
What are renewable resources?
Resources with the ability to reproduce through biological or natural processes and which will not run out.
What is over-fishing?
Catching large, unlimited amounts of fish which leads to reduced amounts of fish over time.
What is over-grazing?
Abusing the soil by allowing animals to graze on the same area.
What are needs?
Things we require in order to survive. 🍞💧
What are wants?
Things that make our lives more comfortable, but we do not need them to survive. 🚗🎮🛌
What does it mean to replenish?
To bring back to how much there was before.
What does depleted mean?
Used up/ all finished so that nothing is left.
What does perpetual mean?
Going on forever
What does conventional mean?
Common/ commonly used
What are metal ores ?
Metals (minerals) below the earth’s surface
What are fossil fuels?
Items such as oil, coal and gas that take millions of years to form within the earth from dead animals and plants.
What is aquifer?
Underground water
What are the 3 types of resources?
Perpetual natural resources ☀️🌊
Conventional resources 🐟
Non-renewable resources 💎
What are conventional renewable resources?
Resources that can be depleted if not used wisely. 🐟
What are non-renewable resources?
Resources that can’t be renewed. 💎
What are perpetual resources?
Resources that will go on forever. 🌊☀️
What is resource depletion?
When raw materials are used up.
In what 6 ways do we deplete?
- Poor farming methods
- Pollution
- Mining
- Lack of control over use of resources
- Wasting resources
- Not replanting trees and plants
What are 3 effects of over-fishing?
Reduces amount of food 🍽
Unemployment 👷🏾
Harms many marine animals 🐬
How long are gill nets?
40-60km
About how much of the fish/ marine animals killed by gill nets can be used?
50%
How can over-grazing be fixed?
Rotational grazing
What is sustainable use of resources?
Improving the management of natural resources.
What organization educates South Africans about what types of fish can be eaten?
South Africa Sustained Seafood Initiative
SASSI
What can encourage sustainable fishing?
Limiting the amount (quota) or size of fish caught.
Look at
Carbon footprint 👣
What is food security?
Having enough food for each person to meet their nutritional needs every day
What is the daily energy supply in South Africa?
2 950 calories per person.
What are 3 sustainable farming methods?
No-till farming: working the soil only once.
Crop rotation: alternating the type of crop in a
certain area.
Companion planting: using plants to assist each
each other by repelling pests
that feed on plant roots.
What are genetically modified crops?
Crops that are altered genetically
😝
How are crops genetically altered?
A gene from one plant is inserted into the DNA of another.
Name 4 advantages of genetically modified crops.
✔️ Resistant to pests
✔️ Increased nutritional value
✔️ Increased food production by increased
resilience.
✔️ Can help to prevent diseases in crops and
livestock.
What are 4 disadvantages of genetically modified crops?
❌ Can lead to mutated species which could
threaten natural systems.
❌ Risk of unethical experimentation.
❌ Can negatively impact the environment,
e.g. Pests becoming immune to GM crops.
❌ Can cause medical or health implications.
