Explore key concepts of fertilizer application in agriculture, including nutrient types, timing, methods, and sustainability considerations. Sharpen your understanding of how fertilizers support healthy crop growth and soil management.
Which of the following is considered a primary macronutrient supplied by most commercial fertilizers for crops such as corn or wheat?
Explanation: Nitrogen is one of the three primary macronutrients, crucial for plant growth and commonly provided in fertilizers. Zinc and boron are micronutrients needed in much smaller amounts. Chloride is also a micronutrient and is supplied less frequently than nitrogen.
Why is the timing of fertilizer application important for maximizing nutrient uptake in crops like rice and wheat?
Explanation: Nutrient uptake is often greatest during specific stages such as early growth or flowering, making timing critical. The other options are incorrect because nutrient requirements vary throughout the growth cycle and do not peak solely at harvest or remain constant across all seasons.
Which fertilizer application method places nutrients close to plant roots to minimize loss in crops like maize?
Explanation: Band placement involves applying fertilizer in narrow strips near or within the seed row, increasing efficiency and reducing wastage. Foliar sprays target leaves, broadcast spreading may lead to runoff, and hydroponic feeding is not typically used for soil-grown maize.
Over-application of nitrogen fertilizer can lead to which environmental problem in nearby water bodies?
Explanation: Eutrophication occurs when excess nutrients enter water bodies, causing algal blooms and oxygen depletion. Soil compaction and drought are not direct consequences of fertilizer runoff, and acid rain is mostly caused by atmospheric pollutants, not fertilizer use.
Which statement best describes a key difference between organic and synthetic fertilizers regarding soil health over time?
Explanation: Organic fertilizers contribute organic matter that benefits soil structure and microorganisms. Synthetic fertilizers can indeed provide nutrients, but may not support soil biology as effectively. The other statements are inaccurate regarding nutrient release and solubility.