Which one of the following concerns soil?

The correct answer is A) Edaphic. The term comes from the Greek edaphos, meaning ground or soil, and in ecology it refers to the soil conditions that shape plant and animal life: texture, structure, pH, moisture, organic matter and nutrient status.

• B) Climatic is wrong. It refers to weather and climate factors such as temperature, rainfall, humidity, wind and light, which are not soil properties.
• C) Biotic is wrong. It refers to living components such as plants, animals, microbes and humans. Soil contains biota, but biotic is not the term for soil itself.
• D) Topography is wrong. It refers to landform features such as relief, slope, aspect and altitude. Topography influences soil formation and erosion, but it does not describe the soil.

The core concept is the ecological classification of environmental factors into climatic, edaphic, biotic and topographic. For Mains, this links to land degradation, soil erosion, and the distribution of Indian soil types (alluvial, black, red, laterite) in the Geography syllabus, and to the agro-climatic zoning of crops.

Trap: Aspirants sometimes pick Topography because soil formation depends on relief. Remember that the question asks what concerns soil itself, and the term for that is edaphic.