Natural and constrainment-induced factors influencing the breakdown of dogwood and oak leaves. D'Angelo, W. & J.R., D. 1992.
Natural and constrainment-induced factors influencing the breakdown of dogwood and oak leaves [pdf]Paper  abstract   bibtex   
Breakdown rates and microbial colonization patterns of dogwood and oak leaves were measured between November and June of 1987-88 and 1988-89. Leaves were placed in artificial streams loose (unconstrained), in bags, or in packs. Discharge was maintained at approximately 0.25 I s " 1 , and no shredders were present in the streams. Average microbial biomass as ATP, for all species and treatments, increased from near 0 mg g\textasciitilde ' AFDW in November to over 8 mg g\textasciitilde l AFDW in June. Microbial respiration increased from about 0.01 \textasciicircumg glucose respired hr-g\textasciitilde ' AFDW in November to about 0.03 \textasciicircumg hrg\textasciitilde ' AFDW in June. Microbial biomass and activity were significantly greater on dogwood leaves than on oak leaves. Dogwood and oak leaf breakdown rates were fastest when unconstrained. -0.0034 and -0.0027 degree-day"' respectively. Breakdown rates of dogwood leaves were faster in bags (-0.0025 degree-day"') than in packs (-0.0015 degree-day"') while rates of oak leaves were not significantly different between bags and packs (-0.0014 and -0.0018 degree-day"' respectively). Breakdown rates of dogwood and oak leaves obtained in this study were much slower than those obtained by other investigators either in the presence or absence of shredders. A comparison of results from this study with results from other studies revealed that dogwood leaves may be affected more by turbulence, while oak leaves may be influenced more by shredder activity.

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