Abee, Albert; Lavender, Denis. 1972. Nutrient cycling in throughfall and litterfall in 450-year-old Douglas-fir stands. In: Research on coniferous forest ecosystems: first year progress in the coniferous forest biome, US/IBP: Proceedings of a symposium; 1972 March 23-24; Bellingham, WA. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Forest and Range Experiment Station: 133-143.
Comparisons of nutrient concentrations (N, P, K+, Ca++, Mg++) found in canopy throughfall and litterfallwere made on the H. J. Andrews Experimental Forest. Six old-growth Douglas-fir (Pseudotsuga menziesii)stands were studied which represented six forest communities common to the western Cascades of Oregon. Thesecommunity types span a large portion of the temperature and moisture gradients present in the area Thepreliminary data indicate that nutrient concentration in throughfall was highest during the summer and fall, andlowest during the winter. Nutrient input through throughfall generally followed the same trends. Nutrientreturn through litterfall was greatest in the needles. More amounts of N, P, and Ca++ were transferred to the soilthrough litterfall than through through fall, while more K+ and Mg++ were added to the soil through through fall.Litterfall was maximum during the winter. Future studies will correlate the results from the nutrient analysis tothe moisture and temperature gradients.