Weight and calcium losses from decomposing tree leaves on land and in water.
In a spring-fed perennial stream, complete decomposition of Acer leaves required up to 24 weeks and that of Liriodendron and Quercus leaves less than 44 weeks. On land, first year losses were: 55, 44 and 33% in weight, and 54, 38 and 35% calcium for Acer, Liriodendron and Quercus, respectively. These losses were low between the 8th and 20th week but they accelerated in spring and summer. Losses in weight and calcium in the stream were much higher than on land and the contribution of allochthonous material in the stream chemistry is discussed.