Effects of earthworm invasion on morphology, carbon, and nitrogen of a forest soil
Alban, D.H.; Berry, E.C.
Applied Soil Ecology 1: 243-249
ISSN/ISBN: 0929-1393 DOI: 10.1016/0929-1393(94)90015-9
Soil samples were collected over 14 years from a sandy loam forest soil in northern Minnesota. At the start of the study (1978) the vegetation was a 60-year-old mixed stand of Betula papyrifera, Populus tremuloides, P. grandidentata and Acer rubrum. During the 14 years, earthworm numbers increased from zero to 592/msuperscript 2, the forest floor weight and thickness decreased by about 85% and the E horizon was completely replaced by an A horizon. Development of the A horizon resulted in an increase of carbon and nitrogen concentrations but no changes in soil pH or C:N ratios in the surface mineral soil. Total soil carbon to a depth of 50 cm decreased at an annual rate of 0.6 t/ha during the study.