A ROBOTIC PROCEDURE FOR THE DETERMINATION OF SOIL LIME REQUIREMENT

A commercial laboratory robot has been programmed to aid in the determ ination of soil lime requirement. Soil samples submitted to our labora tory, after drying, grinding, acid sieving, are manually scooped into racks of pre-weighed glass tubes. From this point onward, the robot pe rforms all functions. The weight of soil in each tube is obtained usin g an analytical balance. Deionized water is added using a mobile piper , and the contents of each tube stirred, and optionally centrifuged. T he soil/water pH (pHw) is determined using a mobile combination electr ode. SMP buffer solution is added, the contents stirred, optionally ce ntrifuged again, and the soil/SMP buffer pH (pHSMP) value is obtained. The weight and two sets of pH data for each soil sample are transferr ed to disk, and lime requirement results calculated using a computer s preadsheet program.