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parts. PART I — Multiple Choice 1. Which statement best describes soil fertility? A. The ability of soil to produce maximum yield under any condition B. The soil’s ability or potential to supply essential nutrients needed by plants C. The ability of soil to prevent erosion D. The ability of soil to retain only water 2. Which statement correctly describes soil productivity? A. The ability of soil to supply nutrients only B. The ability of soil to produce a good crop yield under a given management system C. The amount of organic matter in soil D. The ability of soil to retain water 3. Which statement is correct regarding soil fertility and productivity? A. All fertile soils are productive B. All productive soils are fertile, but not all fertile soils are productive C. Fertility and productivity are exactly the same D. Productive soils do not need nutrients 4. Soil fertility is best described as the soil’s: A. Performance B. Potential or inherent capability to supply nutrients C. Rate of erosion D. Amount of sand 5. Soil productivity depends on: A. Soil fertility only B. Fertility and other factors including management C. Soil color only D. Soil texture only 6. What are edaphic factors? A. Factors related to climate B. Factors related to animals C. Factors related to soil that affect plant growth D. Factors related to sunlight only 7. Soil texture refers to the relative amounts of: A. Organic matter, water, and air B. Sand, silt, and clay C. Nitrogen, phosphorus, and potassium D. Roots, microorganisms, and water 8. Which soil generally holds more water? A. Sandy soil B. Clayey soil C. Gravelly soil D. Rocky soil 9. Soil structure refers to: A. The color of soil B. The amount of sand in soil C. How soil particles group together into aggregates D. The amount of water in soil 10. Which practice can improve soil structure? A. Excessive tillage B. Continuous heavy machinery use C. Adding organic matter D. Repeated soil compaction 11. Soil aeration refers to: A. The amount of water in soil B. The amount of air in spaces between soil particles C. Soil temperature D. Soil acidity 12. What happens to soil aeration when soil becomes compacted? A. Air spaces increase B. Air spaces decrease C. Nutrients automatically increase D. Root growth improves 13. Soil temperature directly affects: A. Seed germination and root growth B. Soil texture C. Soil classification only D. Amount of sand 14. Soil pH affects: A. Nutrient availability and microorganism activity B. Only soil color C. Only soil temperature D. Crop spacing 15. Which condition can restrict root growth? A. Loose soil B. Well-aerated soil C. Soil compaction D. Good soil structure 16. Which is a common cause of soil compaction? A. Crop rotation B. Heavy machinery and repeated traffic C. Adding organic matter D. Leaving crop residues 17. Beneficial soil microorganisms are important because they: A. Stop all plant diseases B. Decompose organic matter and help release nutrients C. Remove all water from soil D. Cause soil erosion 18. Organic matter can improve: A. Water-holding capacity B. Soil structure C. Nutrient availability D. All of the above 19. Which two elements are important sources of food/nutrients involved in microbial activity and decomposition? A. Carbon and nitrogen B. Calcium and iron C. Potassium and sulfur D. Sodium and chlorine 20. Which cropping system involves growing the same crop repeatedly? A. Crop rotation B. Monocropping C. No-tillage D. Minimum tillage 21. Which is an example of crop rotation? A. Corn → corn → corn B. Corn → soybean → corn C. Rice → rice → rice D. Corn → corn → soybean only once 22. One advantage of crop rotation is that it can: A. Always eliminate all pests B. Help maintain soil fertility and reduce some pests and diseases C. Increase soil compaction D. Always increase erosion 23. Conventional tillage generally involves: A. No soil disturbance B. Repeated plowing and harrowing C. Leaving all soil untouched D. Planting without any preparation 24. Minimum tillage: A. Uses less soil disturbance than conventional tillage B. Uses more plowing than conventional tillage C. Always removes crop residues D. Completely prevents erosion 25. No-tillage means: A. Soil is heavily plowed before planting B. Crops are planted with minimal soil disturbance C. Soil is completely removed D. Crops are never planted 26. Soil erosion is: A. The addition of nutrients to soil B. The removal and movement of soil by water or wind C. The movement of water into soil D. The decomposition of organic matter 27. Why is soil erosion harmful to soil fertility? A. It removes fertile topsoil containing nutrients and organic matter B. It increases all nutrients C. It increases soil organic matter D. It improves root growth ⸻ PART II — True or False 28. A fertile soil is always a productive soil. 29. All productive soils are fertile. 30. Soil fertility is one factor that affects soil productivity. 31. Soil productivity considers the crop yield obtained under a given management system. 32. Soil texture refers to the amount of sand, silt, and clay. 33. Sandy soil generally drains water faster than clayey soil. 34. Soil structure refers to how individual soil particles group together into aggregates. 35. Soil structure can never be changed by management practices. 36. Good soil structure promotes movement of air and water and supports root growth. 37. Compacted soil usually has fewer pore spaces. 38. Plants need soil water for germination, nutrient absorption, and growth. 39. Soil pH has no effect on nutrient availability. 40. Very acidic or very alkaline soils can make some nutrients unavailable. 41. Soil microorganisms help in decomposition and nutrient cycling. 42. Having more microorganisms automatically means the soil is always more fertile. 43. Organic matter can improve water-holding capacity and soil structure. 44. Monocropping means growing different crops in sequence. 45. Crop rotation can help maintain soil fertility. 46. Minimum tillage causes more soil disturbance than conventional tillage. 47. No-tillage minimizes soil disturbance. 48. Soil erosion can remove nutrient-rich topsoil. ⸻ PART III — Identification 49. Ability of soil to supply essential nutrients needed by plants. 50. Ability of soil to produce a good crop yield under a given management system. 51. Factors related to soil that affect plant growth. 52. The relative amounts of sand, silt, and clay in soil. 53. The arrangement or grouping of soil particles into aggregates. 54. The amount of air present in the spaces between soil particles. 55. The pressing of soil particles closely together, reducing pore spaces. 56. Dead plants, animals, and other organic materials present in or added to soil. 57. Growing the same crop repeatedly on the same land. 58. Growing different crops in sequence on the same land. 59. A tillage system involving more intensive soil disturbance such as repeated plowing and harrowing. 60. A tillage system that uses less soil disturbance than conventional tillage. 61. A system where crops are planted with minimal soil disturbance and crop residues are often left on the surface. 62. The removal and movement of soil by water or wind. ⸻ PART IV — Situational Questions 63. A farmer has soil that contains enough nutrients, but the soil is heavily compacted. The roots cannot penetrate properly and the crop grows poorly. Is the soil fertile, productive, or both? Explain. 64. A clayey field retains a lot of water, while a sandy field drains water quickly. Which soil property is responsible for this difference? 65. A farmer repeatedly uses heavy machinery on the same field. The soil becomes dense, roots struggle to grow, and water movement decreases. What soil condition has developed? 66. A farmer adds organic matter to the soil. After some time, the soil has better structure, improved water-holding capacity, and increased nutrient cycling. What soil component caused these improvements? 67. A farmer plants corn every year on the same land: Corn → Corn → Corn → Corn. What cropping system is being practiced? 68. Another farmer plants Corn → Soybean → Corn → Soybean. What cropping system is this? 69. A farmer reduces plowing and harrowing to protect the soil from erosion. What tillage system is being practiced? 70. A farmer plants crops without conventional plowing and leaves crop residues on the soil surface. What management system is this? 71. A field has good fertility and sufficient nutrients, but poor drainage, severe compaction, and poor management result in low crop yield. What does this demonstrate about soil fertility and productivity? 72. Heavy rainfall causes the removal of the nutrient-rich topsoil from a field. Which soil management problem is occurring? ⸻ PART V — Challenge Questions 73. Why is a fertile soil not necessarily a productive soil? 74. Why is soil fertility considered a potential or inherent capability, while soil productivity refers more to actual performance or yield? 75. Explain how soil texture, soil structure, soil water, and soil aeration work together to affect plant growth. 76. Explain how soil compaction can lead to stunted plant growth. 77. Explain why organic matter is important in maintaining soil fertility. 78. Compare monocropping and crop rotation in terms of soil fertility and management. 79. Compare conventional tillage, minimum tillage, and no-tillage. 80. Explain how soil erosion can cause both soil fertility decline and reduced soil productivity. Quick distinction to memorize Soil Fertility = POTENTIAL → ability to supply essential nutrients. Soil Productivity = PERFORMANCE → ability to produce a good crop yield under a given management system.