Natural Resource Management and Sustainable Agriculture
The resources
Natural resources in farming include soil, water, rangeland/pasture, forests and trees, wildlife and biodiversity. Sustainable agriculture meets present needs without reducing the ability of future generations to meet theirs. Know the three pillars: economic (profitable), social (fair, acceptable) and environmental (protects soil, water and biodiversity).
Land and soil degradation
Know the causes and controls of soil erosion (wind and water), nutrient depletion, salinisation, compaction and overgrazing. Controls include contour ridges, mulching, cover crops, minimum tillage, windbreaks, rotational grazing, stocking-rate limits and re-seeding of degraded range.
Water and rangeland management
Cover water harvesting (catchments, tied ridges, potholes, roof collection), irrigation efficiency (drip, scheduling, avoiding over-irrigation and salinisation), and protection of wells and boreholes from contamination. On rangeland, know carrying capacity, rotational grazing, rest periods, bush control and the danger of overstocking.
Agroforestry and biodiversity
Agroforestry combines trees with crops or livestock for shade, fodder, fuel, windbreaks and soil improvement. Biodiversity supports pollinators and natural enemies of pests, so conserving hedgerows and avoiding indiscriminate pesticide use matters.
Worked example
A communal grazing area is bare and eroded near the water point. Reasoning: overstocking and continuous grazing concentrate animals near water. Response: reduce stocking rate to carrying capacity, rotate grazing with rest periods, move water points, reseed bare patches and control bush encroachment. State the cause, the intervention and the expected outcome.