Organic halogens in spruce forest throughfall

Deposition of dissolved organic halogens by throughfall was determined in a small spruce forest site in Denmark (56°28ʹN, 8°24ʹE). The mean annual deposition of dissolved organic halogens was 377 g ha−1yr−1, and larger than the general deposition by precipitation. No relationship between the position of the collectors and the forest edge or dominating wind-direction was found, suggesting that dry deposition was not a major source. The concentration of organic halogens was related to that of organic carbon and decreased from the tree-trunk and outwards. In addition, the concentrations were higher during the growing season than during the dormant season. This indicates that the major part of the organic carbon and organic halogens in spruce forest throughfall originates from canopy leachates or other internal sources.