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