🍂 • Module 3 : Soils & Sustainable Agriculture Flashcards
This lesson covers soil composition, its role in plant growth, agricultural types, methods to increase yields, and the environmental impacts of farming. It also explores soil erosion, its causes and consequences, and strategies for sustainable agriculture.
What are the four main components of soil?
1 — Mineral particles (sand, silt, clay)
2 — Organic content (plants, animals, microorganisms),
3 — Air
4 — Water
Why is soil air content important for plant growth?
It provides oxygen for root respiration and supports soil microorganisms that help with nutrient cycling.
What are the key mineral ions needed for growth?
Nitrate (NO₃⁻) for proteins,
Phosphate (PO₄³⁻) for energy transfer and root growth,
Potassium (K⁺) for enzyme activation and water regulation.
What are the main differences between sandy and clay soils?
Sandy soil has high air content, drains quickly, and is easy to cultivate but lacks nutrients.
Clay soil retains water, is nutrient-rich but has poor drainage and is harder to cultivate.
What are the three main types of agriculture?
Arable (crop farming),
Pastoral (livestock farming),
Mixed (both crops and livestock).
What is the difference between subsistence agriculture and commercial agriculture?
Subsistence agriculture is small-scale, producing food for personal or local consumption.
Commercial agriculture is large-scale, focused on profit and mass production.
How does crop rotation improve agricultural yields?
It prevents soil nutrient depletion, reduces pest buildup, and improves soil structure.
Name two biological methods of pest control…
Introducing natural predators (ex. ladybugs for aphids),
Using bacteria-based insecticides (ex. Bt)
What are the negative effects of overusing fertilizers?
Water pollution (eutrophication), soil degradation, and disruption of natural nutrient cycles.
How does irrigation mismanagement cause salinization?
Excessive watering causes water to evaporate, leaving behind salt deposits that make soil infertile.
What are the main causes of soil erosion?
Removal of vegetation (over cultivation, overgrazing),
Water erosion (rain, flooding),
Wind erosion (strong winds in dry areas).
How does mechanization increase agricultural yields?
It speeds up farming processes,
Reduces labor costs,
Allows for large-scale production.
What is hydroponics, and how does it help in agriculture?
A method of growing plants without soil, using nutrient-rich water solutions, which increases yields and conserves space and water.
What are two methods to reduce soil erosion?
Terracing — creating steps on slopes to slow water runoff
Windbreaks — Planting trees to block wind.
What is trickle-drip irrigation, and why is it sustainable?
A system that delivers water directly to plant roots in small amounts, reducing water waste and preventing salinization.
