-To show that intense management can increase the rate at which soil quality improves

1. GA GB F2 F1 F3 F4 N Field Greenhouse R2 = 0.9603 Regression between SOM and CEC in soil samples from individual sub-sample plots at Jones Farm. R2 value shows the strength of the relationship. R2 = 0.7249 Regression between pH and CEC in soil samples from individual sub-sample plots at Jones Farm. R2 value shows the strength of the relationship. Comparison of soil properties in raised bed greenhouse and adjacent fallow fields: effects of 3 years of intense organic management at the Jones Farm Ona Lindauer, Shannon Morris, Rob Stenger Research Project for Systems Ecology (ENVS 316) Fall ‘04 Oberlin College, Oberlin, OH Main Objective • -Our two study areas were • intensively managed greenhouse beds (planted in April 2002 after leaf mulch and chicken manure fertilization) • 2) unmanaged fallow fields (uncultivated since 2000) Results & Discussion • -To show that intense management can increase the rate at which soil quality improves • -To compare soil quality between two different management intensities (greenhouse beds and fallow fields) by testing the following soil properties: • -% Soil Organic Matter (SOM) • -pH • -Cation Exchange Capacity (CEC) • -% base cation saturation ([Ca2+], [Mg2+]) Comparison of average soil properties from averaged sub-plot data at Jones Farm, with standard error bars and base cation concentrations adjusted for scale. Differences in pH, % SOM, CEC, [Mg2+], and [Ca2+] between our two sample sites were all highly significant. Hypotheses • Three years of intense management will give the greenhouse beds a higher SOM. • Higher SOM in greenhouse beds will lead to a higher CEC • Higher pH in greenhouse beds will lead to a higher % base cation saturation Conclusion • -Greater SOM content and higher pH mean more cation exchange sites for base cations to occupy. • -Higher SOM found in intensively managed organic agricultural soils may have a higher CEC than soils which do not receive high inputs of organic material. • -A higher pH may lead to a higher CEC. • -The rate of soil quality improvement observed as a result of intensive soil management at the Jones Farm can be used to guide agricultural practices elsewhere. The Jones Farm located in Northeast Ohio with sample areas. GA and GB are the greenhouses. F1-4 are the fallow field sample sites. Methods -We used standard techniques (Petersen 2004) to extract soil cations and assess CEC with sequential additions of NH4Cl and KCl. -CEC was measured from the ammonium extract using an ammonium probe, base cation concentrations were assessed using a Dionex Ion Chromatograph -% SOM was measured via combustion and pH was taken with a pH probe. Background -The Jones Farm is an organic farm managed as part of the Oberlin Sustainable Agriculture Project since 2000, prior to which the farm was under conventional roundup-ready soybeans cultivation. -Soil quality has not been fully assessed since 2000. -Current assessment could inform future management decisions in soil development. Works Cited Petersen, J.E. 2004. Methods for analyzing aquatic ecosystems, unpublished.