Bird, G. W., J. Smith, M. Berney, and R. Gore
Presented at the All Scientist Poster Reception (2006-05-09 )
A nematode community structure standard for Michigan, using absolute and relative population densities was developed from two research projects for comparative analysis of natural and human-managed ecosystems. KBS LTER and LFL 1996-1999 data are being used as independent data sets for model validation. The absolute densities of the standard for woodlot, old field succession, certified organic and conventional agriculture systems are 500, 1,700, 3,500 and 200 per 100 cm3 soil, respectively. The components for the relative densities are bacterivores, fungivores, herbivores, omnivores, carnivores and algavores. Major differences in relative densities exist among the four types of ecosystems. Spring and fall nematode community structure of KBS-LTER old field succession one-year, 10-years and 30-years post disturbance were highly correlated with the standard. In general, absolute population densities associated with the KBS-LFL (conventional monoculture, conventional rotation, integrated compost and organic) were significantly less than those associated with the old-field successions and were a good fit with the conventional standard, regardless of the type of KBS production system management. Fall relative densities of bacterivores were higher in the LFL organic system compared to conventional corn monoculture. Absolute population densities of herbivores were higher in the LFL conventional compared organic system. The temporal dynamics of the absolute population densities varied among growing seasons, but were always lowest in the summer and higher in the spring and fall. In general, KBS LTER and LFL data provide at least partial validation of the 2006 Michigan Nematode Community Structure Standard.Back to Poster Titles
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