What do fungi help improve in soil?

• A. Aggregation and carbon storage
• B. Nutrient availability only
• C. Water retention only
• D. Soil depth

Answer: (A)

Fungi boost soil structure by weaving networks of hyphae that physically bind soil particles into stable aggregates. A key player here is glomalin, a glycoprotein produced by many fungi (especially arbuscular mycorrhizal fungi) that acts like a glue holding particles together. These aggregates create pore spaces that enhance water infiltration and retention, improve aeration, and reduce erosion—benefits particularly important in rangeland soils prone to crusting and compaction. Fungi also contribute to soil carbon storage because their biomass and glomalin add stable organic matter to the soil, helping sequester carbon over the long term. While fungi do help with nutrient uptake by extending the root system for access to minerals, the most complete match to the idea is the combination of better aggregation and increased carbon storage. The other choices capture parts of what fungi do but miss the broader impact on soil structure and carbon.