Which practice best improves soil structure and increases organic matter while protecting against erosion?

• A. Removing crop residues after harvest.
• B. Incorporating green manures and maintaining cover crops.
• C. Relying solely on synthetic fertilizer.
• D. Tilling aggressively every season.

Answer: (B)

This question focuses on how soil management affects soil structure, organic matter, and erosion protection. Incorporating green manures and keeping cover crops continuously feed the soil with biomass and keep roots active in the ground. Green manures are grown to be turned back into the soil, adding organic matter and feeding soil life. The roots from these plants create and preserve soil structure, helping form stable aggregates that improve porosity and water infiltration. Cover crops shield the soil surface year-round, reducing the impact of raindrops, lowering runoff, and further supporting soil aggregation. Together, these practices raise organic matter content and enhance soil structure, while providing a strong defense against erosion.

Removing crop residues removes protective cover and the carbon input that sustains soil biology, making soil more vulnerable to erosion and crusting. Relying only on synthetic fertilizer supplies nutrients but does not build organic matter or soil structure, so long-term soil health and erosion resistance can suffer. Aggressive tillage breaks up aggregates, disrupts soil life, and tends to worsen erosion by destroying structure and reducing porosity.