NCERT Class 8 Science — Chapter 1: Crop production and management

Which one of the following is an organic soil amendment derived from the decomposition of plant or animal waste?

Consider the following statements regarding the preparation of soil: 1. Loosening the soil makes it compact and prevents root penetration. 2. Turning the soil brings nutrient-rich soil to the top for plant utilization. 3. Loosened soil promotes the growth of earthworms and soil microbes. Which of the statements given above is/are correct?

With reference to agricultural implements, consider the following statements: 1. A ploughshare is the strong triangular iron strip found in a plough. 2. A hoe is a tool used exclusively for sowing seeds. 3. A cultivator is a manual tool used for harvesting crops. Which of the statements given above is/are correct?

Consider the following statements regarding the sowing of seeds: 1. Damaged seeds are generally lighter than healthy seeds and float on water. 2. The traditional tool for sowing seeds is shaped like a flat blade. 3. A seed drill ensures that seeds are covered by soil after sowing to protect them from birds. Which of the statements given above are correct?

With reference to the use of manure and fertilisers, consider the following statements: 1. Continuous cultivation of crops enriches the soil with nutrients. 2. Manure is an organic substance obtained from the decomposition of plant or animal wastes. 3. Fertilisers are rich in plant nutrients like nitrogen, phosphorus, and potassium. Which of the statements given above is/are correct?