The in ̄uence of row position and selected soil attributes on Acarina and Collembola in no-till and conventional continuous corn on a clay loam soil

Population abundances of both Acarina (mites) and Collembola (springtails) were examined for continuous corn grown under no-till and conventional management practices on a clay loam, an Orthic Humic Gleysol (Typic Haplaquoll) near Ottawa, Ont., Canada (Lat. 458 220 N; Long. 758 430 W). For each tillage practice, samples for soil faunal extraction and soil attribute characterization were taken periodically during the growing seasons of 1989 (5 samplings) and 1990 (4 samplings). Each time, samples (0±5 cm depth) were taken every 15 cm across a 1.5 m transect spanning three rows of corn that included both a traf®c and a non-traf®c row in order to assess if population abundances were signi®cantly in ̄uenced by soil attributes related to changes in disturbance and compaction due to row position. Row position had a signi®cant effect (analysis of variance based on split±split plot model) on Cryptostigmata in 1989, and in 1990, on Prostigmata, Onychiuridae, and Cryptostigmata. From canonical correlation analysis, for 1989 and 1990, respectively, 71% and 61% of the variation in the biotic data set could be explained by variation in the abiotic data. Crown copyright # 1999 Published by Elsevier Science B.V. All rights reserved.