The effect of seasonal drying on sulphate dynamics in streams across southeastern Canada and the northeastern USA J. G. KerrM. C. EimersI. F. CreedM. B. AdamsF. Beall • D. BurnsJ. L. CampbellS. F. ChristopherT. A. ClairF. Courchesne • L. DuchesneI. FernandezD. HouleD. S. JeffriesG. E. Likens •