MCQs Soil Science-52 Posted on May 10, 2025August 30, 2025Author agropublishers 0 1. Macronutrients are required in large amounts and normally constitute __________ of a plant’s dry weight Less than 400 mg kg –1 (0.04%) 1000 mg kg –1 (0.1%) or more approximately 500 mg kg –1 (0.05%) 10,000 mg kg –1 (1.0%) or more 2. During which geologic time did Earth form and undergo its early development? Mesozoic Paleozoic Cenozoic Precambrian 3. How can heavy metal-contaminated soil be improved? Amendments Phyto-stabilization Phytoremediation All of these 4. Exchangeable and soluble metal ions in soils are termed as _________ Fixed Ions Residual Ions Adsorbed Ions Available Ions 5. __________ is a soil particle that feels powdery to the touch when dry Loam Sand Clay Silt 6. What is the primary mechanism by which soil organic matter enhances soil nutrient retention? Regulating Cation exchange capacity (CEC) Soil pH buffering Improving soil structure Improving water-holding capacity Reducing soil porosity through compaction 7. Which of the following practices can reduce evaporation and increase infiltration? Mulching Overgrazing Siltation Crop Rotation 8. ________________ does NOT significantly affect the bioavailability of toxic chemicals Soil pH Chemical solubility All of these Organic matter content Atmospheric pressure 9. Phosphorus (P) precipitation, along with limited plant availability in soil with high pH, is mainly attributed to ___________? High level of organic matter Low microbial activity High calcium content High iron (Fe) and aluminum (Al) content 10. _________ rocks are formed from the cooling and crystallization of magma deep within the Earth’s crust Sedimentary None of these Igneous Metamorphic Loading … Question 1 of 10
