Evaluation of root effects on soil organisms under different fertilization regimes by comparing rhizosphere and interrow soil in a wheat field

Abstract

Or ri ig gi in na al l r re es se ea ar rc ch h a ar rt ti ic cl le e

Relationships among distribution of fine roots, soil DOC concentration and Collembola

“…In this experiment, the abundance of Collembola showed no significant correlation with fine root The abundance of Collembola and fine root biomass were showed by the amount in a subsample divided by the weight of the subsample soil, as follows: Y = X s / W s , where X s represents the contents in a subsample, and W s is the weight of the subsample soil (kg). biomass and DOC concentration under either the high-or low-light conditions, although many previous studies have shown that microarthropod abundances were higher around plant roots than in the bulk soil , Parmelee et al 1993, Eo and Nakamoto 2007. In the present experiment, water content and position in the pot, which are other factors involved in collembolan distribution, also did not affect the distribution of Collembola.…”

“…Although this study used mineral soil containing little carbon in order to detect low DOC concentration released by fine roots, significant correlation between roots and microarthropods was not detected. Whereas previous studies were conducted in the field (Wiggins et al 1979, Eo andNakamoto 2007) or used field-collected soils in experimental studies (Parmelee et al 1993), this study used artificial sand and akadama soil containing little nutrients as well as carbon, and nutrients were supplied by low-concentration nutrient solution. The soil which was low in nutrients may also have caused the no significant correlation between roots and Collembola by nutrient limits for Collembola rather than carbon limits.…”

“…To assess the effects of roots on soil microarthropod distribution, several studies have compared the abundance of microarthropods between places with abundant roots and those with few roots, under both field and experimental conditions , Parmelee et al 1993, Eo and Nakamoto 2007, Hishi et al 2008. Most of these studies demonstrated that the abundance of microarthropods was greater in root-abundant places, and it was speculated that the release of labile carbon (e.g., root exudation) by the roots resulted in the O Or ri ig gi in na al l r re es se ea ar rc ch h a ar rt ti ic cl le e higher abundance of soil microarthropods , Parmelee et al 1993, Eo and Nakamoto 2007, Hishi et al 2008. Recent studies using stable isotope labeling techniques have demonstrated that soil microarthropods such as Collembola utilize root-derived carbon (Ostle et al 2007, Endlweber et al 2009, and then, the higher abundance of soil microarthropods around plant roots could possibly result from the release of labile carbon by the roots.…”