Grassland Productivity and Water Quality: A 21\u3csup\u3est\u3c/sup\u3e Century Issue

Key points 1. Irrigation and other changes to the hydrological cycle can increase soil and water salinity. 2. Primary salinisation is a natural process that affects much of Europe, Asia, Africa, the Americas and Australia. Secondary salinisation is caused by human activities such as irrigation and land clearing that mobilise salt stored in the soil. 3. The critical water contaminants exported from grasslands are nitrogen, phosphorus, potential pathogens and sediment. 4. The mechanisms responsible for diffuse pollution from grasslands and mitigation strategies are most effectively investigated using a ‘source-mobilisation-transport’ framework. 5. There is a lack of coherent interaction across discipline boundaries that links pollutant sources to impact. Grassland scientists need to work hand-in-hand with hydrologists and limnologists, to understand the water flows and the intricacies of ecological response, in stream or lake, in order to achieve a more coordinated and inclusive, holistic platform of research