Fig. 5. Isotopic [(a) ³⁴S–SO₄^2–, (b) ¹⁵N–NO₃^–, (c) ¹⁵N–NH₄⁺, and (e) ¹⁸O–NO₃^–] and (d) Br^– values measured in throughfall, snowpack, snowmelt, and forest floor (FF) leachates from 31 Dec. 2003 to 8 June 2004. The dashed line indicates the date of the tracer application (18 Feb. 2004), which consisted of enriched ³⁴S–SO₄^2–, ¹⁵N–NO₃^–, and Br^–.