Physical Properties of Soil MCQ's Q & A.docx

**What is the main difference between colloidal clay particles and other types of clay particles?** **A. Their ability to hold water** **B. Their size** **C. Their capacity for ion exchange** **D. Their ability to drain freely** **ANSWER: C** **What type of water is temporarily available to pl...

**What is the main difference between colloidal clay particles and other types of clay particles?** **A. Their ability to hold water** **B. Their size** **C. Their capacity for ion exchange** **D. Their ability to drain freely** **ANSWER: C** **What type of water is temporarily available to plants after heavy rainfall?** **A. Capillary water** **B. Groundwater** **C. Gravitational water** **D. Soil water** **ANSWER: C** **What is the primary source of mineral matter in soil?** **A. Atmospheric deposits** **B. Plant and animal remains** **C. Parent material** **D. Microorganisms** **ANSWER: C** **What is the characteristic of loam soil that makes it more fertile than sandy soils?** **A. Free draining** **B. Low levels of clay** **C. High levels of silt and clay** **D. High levels of silt** **ANSWER: C** **What is the primary factor that determines the soil texture?** **A. Soil water** **B. Soil structure** **C. Parent rock** **D. Organic matter** **ANSWER: C** **What is the primary function of humus in soil?** **A. To improve soil drainage** **B. To provide nutrients to plants** **C. To increase soil temperature** **D. To absorb water and improve soil quality** **ANSWER: D** **What is the term for the small pores within the floccules?** **A. Capillary water** **B. Gravitational water** **C. Macropores** **D. Micropores** **ANSWER: D** **What is the result of soil compaction on soil structure?** **A. Increased pore space** **B. Increased microbial activity** **C. Improved soil structure** **D. Destroyed soil structure** **ANSWER: D** **What is the characteristic of clay soils that makes them prone to waterlogging?** **A. Free draining** **B. Low levels of clay** **C. Poor drainage** **D. High levels of sand** **ANSWER: C** **What is the proportion of pore space in soil that is occupied by air?** **A. 75%** **B. 90%** **C. 50%** **D. 25%** **ANSWER: C** **What is the primary role of soil structure in plant growth?** **A. Water retention** **B. Soil temperature regulation** **C. Aeration and root penetration** **D. Nutrient availability** **ANSWER: C** **What is the term for the water held in the pores within the soil aggregates and between the soil aggregates?** **A. Hygroscopic water** **B. Capillary water** **C. Soil moisture** **D. Gravitational water** **ANSWER: B** **What is the characteristic of sandy soils that makes them easy to work with?** **A. Low levels of silt** **B. Poor drainage** **C. Large air pores** **D. High levels of clay** **ANSWER: C** **What is the significance of soil color in determining soil fertility?** **A. Dark color indicates high fertility** **B. Dark color indicates low fertility** **C. Soil color is not related to soil fertility** **D. Light color indicates high fertility** **ANSWER: A** **What is the effect of lower temperature on plant germination?** **A. Increased water uptake** **B. No effect on germination** **C. Lower germination** **D. Increased germination** **ANSWER: C** **What is the result of erosion on soil?** **A. Improved soil structure** **B. Loss of sediments** **C. Increased soil fertility** **D. Increased organic matter** **ANSWER: B** **Which of the following statements about capillary water is false?** **A. Capillary water is unavailable to plants.** **B. Capillary water is a type of gravitational water.** **C. Capillary water is available for plant uptake.** **D. Capillary water is held in large pores between soil aggregates.** **ANSWER: B** **What is the primary function of colloidal clay particles in soil?** **A. To facilitate ion exchange** **B. To improve soil drainage** **C. To reduce soil compaction** **D. To increase soil fertility** **ANSWER: A** **What is the characteristic of loam soil that makes it more suitable for plant growth?** **A. High clay content** **B. Balanced composition of sand, silt, and clay** **C. Low organic matter content** **D. High sand content** **ANSWER: B** **What is the effect of high levels of sand in soil on its fertility?** **A. Has no effect on soil fertility** **B. Increases soil fertility** **C. Improves soil structure** **D. Decreases soil fertility** **ANSWER: D** **What is the primary difference between soil texture and soil structure?** **A. Soil texture refers to the arrangement of soil particles, while soil structure refers to the proportion of different sized particles.** **B. Soil texture refers to the proportion of different sized particles, while soil structure refers to the arrangement of soil particles.** **C. Soil texture refers to the type of minerals present, while soil structure refers to the type of organic matter present.** **D. Soil texture refers to the color of the soil, while soil structure refers to the smell of the soil.** **ANSWER: B** **What is the effect of high levels of clay in soil on its water-holding capacity?** **A. Improves soil drainage** **B. Increases soil water-holding capacity** **C. Has no effect on soil water-holding capacity** **D. Decreases soil water-holding capacity** **ANSWER: B** **What is the characteristic of humus that makes it beneficial for soil fertility?** **A. It is highly alkaline** **B. It is highly acidic** **C. It repels water and reduces soil fertility** **D. It absorbs water and can greatly improve soil quality** **ANSWER: D** **What is the composition of loam soil?** **A. 50% sand, 30% silt, 20% clay** **B. 40% silt, 30% clay, 30% sand** **C. 40% sand, 40% silt, 20% clay** **D. 40% sand, 30% silt, 30% clay** **ANSWER: C** **What is the primary factor that affects the size of macropores in soil?** **A. Amount of organic matter present** **B. Ratio of sand, silt, and clay particles** **C. Floccule size and arrangement** **D. Soil compaction level** **ANSWER: C** **Which of the following is a consequence of lower soil temperature?** **A. Increased microbial activity** **B. Reduced germination and plant growth** **C. Increased soil aeration** **D. Increased water and mineral uptake** **ANSWER: B** **What is the primary reason for the loss of nutrient availability in soils with poor structure?** **A. Increased erosion and sedimentation** **B. Reduced water retention** **C. Lower CEC (cation exchange capacity)** **D. Decreased microbial activity** **ANSWER: C** **Which of the following is a characteristic of hygroscopic water?** **A. It forms a thin layer around soil particles** **B. It is available for plant uptake** **C. It is held in large pores between soil aggregates** **D. It is temporarily available to plants after heavy rainfall** **ANSWER: A** **What is the primary impact of erosion on soil?** **A. Loss of organic matter and nutrient-rich topsoil** **B. Reduced microbial activity and plant growth** **C. Increased soil compaction and reduced aeration** **D. Improved soil structure and water drainage** **ANSWER: A** **Which of the following is a benefit of good soil structure?** **A. Improved aeration, water drainage, and root penetration** **B. Reduced water retention and increased erosion** **C. Increased soil compaction and reduced microbial activity** **D. Reduced nutrient availability and plant growth** **ANSWER: A** **What is the primary reason for the correlation between soil color and fertility?** **A. Dark-colored soils tend to have higher levels of humus and nutrients** **B. Dark-colored soils tend to have higher temperatures** **C. Light-colored soils tend to have higher levels of sand particles** **D. Light-colored soils tend to have lower water retention** **ANSWER: A** **Which of the following methods is used to determine soil texture?** **A. Soil Sieve analysis** **B. Sedimentation test** **C. Hand testing and sedimentation test** **D. All of the above** **ANSWER: D**