Decomposition dynamics of fine roots in forested ecosystems

Oxford

1984

S. 378-386

4 Abb., 5 Tab., 31 Lit. Ang.

Bandaufführung

137660

Decomposition of live fine roots was studied in four forests: a mixed deciduous forest in Virginia, a mixed deciduous forest and a Pinus resinosa plantation in Massachusetts and an Acer saccharum-Quercus borealis forest in Wisconsin, USA. Decomposition rates were similar in all forests and roots less than 0.5 mm diameter lost dry matter more slowly than those 0.5-3.0 mm diameter. Dry matter losses were initially rapid, but after 10 to 20% of the initial mass was lost the rates slowed significantly. After four years, roots had lost between 20 and 60% of their initia mass. A composite exponential decay model, including a labile and a recalcitrant fraction, described the dry matter losses better than a simple exponential decay model. The low rates of decomposition and nitrogen release indicated that fine roots account for a large portion of the organic matter and nitrogen in the forest soils.