For site specific fertilizer and chemical application, an economically efficient collection, correlation, processing and analyzing of soil samples is needed. To do this, we have created the Automated Work-Station for Soil Analysis (AWSSA). The prototype AWSSA, where soil samples are automatically unpacked, prepared, processed and analyzed in sequential order is based on Rinkis method . All chemistry is built in one sequential line with branches, which permits to utilize only one soil sample (it increases precision and speed of process) for determination of all it parameters, such as pH; particle size;overall humus, alkali-soluble fraction of humus; sesquioxides- carbonates; concentration of the macronutrients; such as NO3, NH4, K, P, Ca, and Mg . The sample preparation unit consists of a mixer where soil is mixed with a water as a slurry, goes through the sieve to screen out large particles, and then through microwave humidity meter to a vessel for it weighting and further analyzing. The concentration of macronutrients are determined by means of ion-selective sensors, which are placed in the flow of the extraction. Ceramic filters have being used for filtering the slurry on different stages in AWSSA. They can be subjected to vacuum for accelerating filtering process and back pressure for cleaning. For the determination of sesquioxides, alkali-soluble fraction of humus, overall humus, and P in AWSSA, we use automated photo-colourimeter. The AWSSA has approximately the size of a writing desk, it is economical and fast. It does one sample per minute after initial process setup time.
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