Soil fertility is NOT conserved by

Analyze the question: The word "NOT" means we are looking for the practice that does not help conserve soil fertility. Four options are conservation methods and one is harmful.

Concept: Soil fertility conservation means keeping the nutrients and structure of the soil and preventing erosion. Let's check each option:

• A. Continuous cropping: Growing crops on the same land year after year without rest or rotation. The crops keep removing the same nutrients, so the soil becomes depleted and loses fertility. This does not conserve fertility.
• B. Contour ridging: Ridges are made along the contour lines of a slope. This slows runoff and reduces erosion, so topsoil and nutrients are kept. It conserves fertility.
• C. Crop rotation: Different crops, including legumes that fix nitrogen, are grown in turn. Nutrients are used differently and replenished, and pests are reduced. It conserves fertility.
• D. Mulching: Covering the soil with dry grass or leaves reduces erosion and evaporation. As the mulch decays, it adds humus and nutrients. It conserves fertility.
• E. Terracing: Step-like platforms are cut on slopes to slow water flow and prevent erosion. It conserves fertility.

Answer: Only continuous cropping depletes the soil, so the answer is A.

Tip: For "NOT conserved" questions, look for the odd one out, the practice that exhausts or exposes the soil, such as continuous cropping, bush burning, overgrazing, or deforestation. The conservation methods usually include rotation, mulching, cover cropping, fallowing, manuring, contour ridging, and terracing.