Globally, over $100 billion of inorganic nitrogen fertilisers are applied to crops and pastures every year. Between 10 and 40% of the applied N is taken up by plants. Much of the remaining 60% to 90% is returned to the atmosphere as ammonia or nitrous oxide – or leached to aquatic ecosystems as nitrate. The use of inorganic N in agriculture is recognised as a highly inefficient – and...
