Journal of the North American Benthological Society, 1995. Paper abstract bibtex
Export of coarse particulate organic matter (CPOM) from three headwater streams at Coweeta was studied continuously for up to 9.5 years. Annual CPOM export among years varied by factors of 9.2 to \textgreater 16 X, much greater than the 3.5 to 5.0 X variation in annual stream discharge. Annual export was more a factor of storm frequency and magnitude. Over 63 to \textgreater 77% of all CPOM export occurred during the largest 20 storms. Export during individual sampling intervals was strongly related to maximum discharge. Leaf export was greatest during the autumn and lowest during the spring and summer months. Export of woody debris was more seasonally variable than that of leaves. Although allochthonous CPOM is the greatest source of organic matter inputs, CPOM represented only 1.8-3.8% of total organic matter export, indicating high retention in these small, high-gradient streams. Retentiveness was illustrated by movement of marked artificial leaves and sticks, which displayed maximum downstream movement of \textasciitilde42 m/yr for leaves and 10 m/yr for sticks. For three years, one stream received seasonal treatments of an insecticide that drastically reduced invertebrate populations. Large increases in leaf litter standing crop were observed compared with untreated streams. However, CPOM export did not increase significantly whereas a massive reduction in FPOM export was found.