What role does soil microbial activity play in nutrient cycling?

Soil microbial activity plays a crucial role in nutrient cycling by facilitating the transformation and release of nutrients essential for plant growth. Microorganisms, such as bacteria and fungi, break down organic matter and decompose dead plant and animal materials. This decomposition process releases nutrients like nitrogen, phosphorus, and potassium into the soil in forms that are available for plant uptake.

Additionally, certain microorganisms can convert nitrogen from the atmosphere into a form that plants can absorb, a process known as nitrogen fixation. Other microbes help solubilize phosphorus from soil compounds, making it more accessible to plants. This ongoing cycle of nutrient transformation by soil organisms is fundamental to maintaining soil fertility and supporting healthy plant growth.

The other options suggest negative impacts or misconceptions about microbial activity, which do not accurately capture the beneficial roles these organisms play in supporting nutrient availability in the soil.