Microbial Phosphorus Gatekeeping:
A recent study published in Nature Geoscience examined the role of soil microbes in phosphorus cycling over 700,000 years in the Cooloola coastal dune system, located in Cooloola National Park, Queensland, Australia.
- Phosphorus (P) is an essential macronutrient required by all life forms. It is crucial for: Energy metabolism (e.g., ATP production), Cell membrane synthesis (phospholipids), Photosynthesis and genetic functions (DNA/RNA).
- In ancient and weathered soils, such as those in Australia, phosphorus levels decline significantly over time due to mineral weathering, making it the primary limiting nutrient in many ecosystems.
- The study discovered that soil microbes—especially fungi and bacteria—act as ‘phosphorus gatekeepers’ by regulating how phosphorus is accessed and cycled in the soil.
- Microbes use several adaptive mechanisms to survive phosphorus scarcity:
- Replacing membrane phospholipids with non-phosphorus lipids,
- Accumulating microbial lipids (fats) that reduce the need for phosphorus,
- Optimising phosphorus uses efficiency in their metabolism.
- This microbial gatekeeping strongly influences how phosphorus becomes available to plants, creating a balance of competition and facilitation: Microbes and plants compete for phosphorus, But microbes aid plants by recycling phosphorus and making it more accessible in the long run.
