Introduction of On-site Soil Analysis and Diagnosis System

Abstract

Crops must absorb all essential elements sufficiently, because a yield of crop is determined by the Minimum which is the growth limiting factor of Liebig's law of minimum. The minimum is determined by soil testing and recommended as a fertilizer corresponding to the amount of crop production for the crop period before cultivation but the amount of the fertilizer is supplied by farmers' experiences on the growing condition of crop during cultivation. Owing to the diversity of soil chemical properties, soil must be categorized to be recommended the adequate amount of fertilizer. Therefore we categorized soil as 8 soil testing types with soil pH and soil organic matter (SOM) of Korean soil information system. We also set up the on-site soil analysis and diagnosis system in order to recommend the nutrients by soil testing during cultivation. The process of system was composed of three steps: 1) analyzing chemical properties of pH and Eh and nutritional properties of N and P and osmotic properties of EC or sum of nitrate and sulfate and chloride, 2) diagnosing soil condition as one of 64 kinds of soil conditions with categorizing with 4 chemical properties and 8 nutritional status and 2 osmotic aspects, 3) recommending the amount of minimum according to the soil condition and soil testing type and how to supply fertilizers by a series of pH buffer and fertilizer and water.

Compositional Characteristics of Major Inorganic Anions in Soil and Plant Water Extracts from Various Farmlands

“…Compared with the total analysis method, which accounts mainly for a long-term integrated accumulation of nutrients, the fresh tissue or cell tests can have advantages of reflecting relatively recent or readily available nutrient contents in the plant compartment. In addition, when commercial plant tissue test kits (strips or ion-selective electrodes) are used, semiquantitative assessment of nutrient status can be done easily on the site (Taber and Lawson, 2007;Kim et al, 2018).…”