Comparison of Physicochemical and Biological Soil Properties in Organic and Conventional Upland Fields

Abstract

Application of organic farming system has been increased recently but change of soil properties due to organic farming system has not been thoroughly studied. The main purpose of this study was to compare physicochemical and biological soil properties between conventional and organic farming system and to identify the most affected soil parameters for two different farming system. Soil samples were collected from upland fields that have been using conventional or organic farming system for over five years. Then, physicochemical and biological soil properties were determined, including bulk density, porosity, pH, electrical conductivity (EC), cation exchange capacity (CEC), soil organic matter, total nitrogen (T-N), available phosphorus, soil respiration, and soil enzyme activities. For soil physical perspective, soils from organic farming system had lower bulk density and higher porosity values than conventional farming system. This result indicate that organic farming system had beneficial effect on soil physical properties. In case of soil chemical properties, the available phosphorus content in soil from conventional farming system was higher than in organic farming system probably due to the continuous use of inorganic fertilizers containing phosphorus in the arable area. For soil biological properties, β-glucosidase and phosphatase activities were higher under conventionally managed soils than organic farming system. Overall, physicochemical and biological soil properties can be varied depending on differently managed farming system and long terms of monitoring is necessary for understanding the change of soil properties between organic and conventional farming system.Soil properties including a) bulk density, b) soil organic matter content, c) β-glucosidase activity, and d) urease activity (CF, conventional farming; OF, organic farming).