Much of the environment is awash with fertilisers, boosting thuggish weeds such as stinging nettles that swamp other wild plants. Nitrate is a big villain in this onslaught, but far less notice is taken of phosphate.



Phosphate is crucial for plant growth and development, and it is estimated that half the world’s food supplies rely on phosphate fertilisers, but this is a dwindling resource that is used very inefficiently, which is leading to widespread pollution. Unlike nitrate, phosphate binds very strongly to the soil, which makes it difficult for plant roots to get hold of. And so farmers apply even more phosphates in fertilisers and manure, although much of that phosphate then sticks to the soil again, driving the levels of phosphate in the soil even higher.

When the phosphorus is gradually released into the soil water, much of it washes away. And so phosphorus pollution is reaching dangerous levels in streams, rivers and other waterways, leading to big blooms of algae that swamp wild aquatic plants and starve fish and other aquatic creatures of oxygen. But work at Reading University is hoping to use bacteria in the soil to break down the unused phosphorus, boosting crop growth and reducing waste.





