Certified Crop Advisor Practice Exam

What is the significance of soil pH in relation to crop production?

1. It affects soil temperature

2. It determines the types of crops that can be grown

3. It affects nutrient availability

4. It controls soil erosion

The correct answer is: It affects nutrient availability

Soil pH is crucial for crop production primarily because it directly impacts nutrient availability. Plants require specific nutrients for growth, and these nutrients are often more or less available depending on the acidity or alkalinity of the soil. When soil pH deviates from the optimal range for a particular crop species, it can lead to nutrient deficiencies or toxicities. For instance, certain essential nutrients like phosphorus become less available in highly acidic or alkaline soils. Conversely, micronutrients like iron may become overly available and cause toxicity in low pH environments. Thus, maintaining an appropriate soil pH is vital to ensure that plants can access the nutrients they need for optimal growth and development. While soil temperature and types of crops that can be grown are important factors in agriculture, they are influenced by, but not determined by, soil pH. Soil erosion is also a significant concern in crop production, but it is not directly controlled by pH levels. Soil pH primarily plays a key role in the availability of nutrients essential for plant health and productivity.