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