The Effects Of Different Grinding Methods On Measured Values Of Available Kin Soil And Formulated Fertilization

The reasons which lead to different measured values of available K in soil after different grindingmethods were studied to provide a scientific basis for available nutrient testing and fertilizer formulating，and thus effectively prevent crop diseases, output reduction, resources waste and environmental pollutionwhich caused by fertilizers’ deficiency or excess. In this paper, three different grinding methods with variesof grinding time were used to deal with the eleven soil samples which were collected from five differentcities in the northeast area after3repetitions.3different grinding methods were used to deal with the soilsamples, and they were hand rolling,2800r/min and25000r/min rolling treatments with grinder. Thedifferent grinding times are0.5min,1.0min and1.5min. After extracted with ammonium acetate solution,potassium was measured by atomic absorption spectrophotometer. And the content of nitrogen andphosphorus were also detected. Estimate the differences in recommended fertilization quantity caused bydifferent grinding methods with nutrient balance method based on the test results.The results showed that the energy of mineral potassium in soil was increased and chemical activitywas improved due to mechanical activation during the grinding process. As a result that soil available Kwas easy to leaching into the solution that lead to the value was more than the actual ones. The availablepotassium content in the soil after25000r/min rolling treatment was significant higher than the other twotreatments. Available potassium content was8.09%-55.77%and6.84%-76.55%higher than hand rollingtreatment and2800r/min treatment, respectively. But the difference between25000r/min rolling treatmentand2800r/min rolling treatment was not significant. The potassium values did not continued to increasewith the extension of the grinding time, because the powder reunion rate and particle refinement rate werecame to balanced gradually, and the release of potassium ions also tended to be stabilized. By contrast,nitrogen and phosphorus did not increase by enhancing mechanical activation strengthens. In the actualproduction process, if the test results were increased, the recommendation fertilizers would be reduced. Thecrop yield would be suffered from serious impacts and could not even reach the target outputs.