What characteristic of boron and chlorine in soil is notable?

The notable characteristic of boron and chlorine in soil is that they are easily leached. This means that these elements can be washed away from the soil profile through the movement of water, typically during heavy rainfall or irrigation events. When boron and chlorine are leached from the soil, it can lead to deficiencies in plants that rely on these micronutrients for various physiological functions.

Boron, for instance, plays a crucial role in cell wall structure and function, while chlorine is important for photosynthesis and stomatal function. Their leaching can result in reduced availability for plant uptake, which may negatively affect crop growth and yield.

The other options do not accurately describe the behavior and role of boron and chlorine in soil. They do not inherently increase soil fertility or help with water retention, nor are they considered reliable indicators of soil health compared to other soil properties and nutrients. Understanding these characteristics helps in managing their application and ensuring that crops receive adequate micronutrients despite their leaching tendencies.