Fungi play a crucial role in nutrient cycling in forests through processes such as decomposition, nutrient absorption, and symbiotic relationships with plants. Fungi break down organic matter, such as dead leaves and wood, into simpler compounds, releasing nutrients like carbon, nitrogen, and phosphorus back into the soil. This helps in replenishing soil fertility, promoting plant growth, and maintaining ecological balance in forest ecosystems. Additionally, mycorrhizal fungi form symbiotic relationships with tree roots, facilitating the exchange of nutrients between plants and soil.