Inspection and detection method for organic matter content in soil

Abstract

The invention belongs to the field of organic matter detection, and discloses an inspection and detection method for organic matter content in soil. The inspection and detection method comprises the following steps: (1) weighing a to-be-detected sample, putting the to-be-detected sample into 250ml of hard triangular flasks, adding a potassium dichromate-sulfuric acid solution, uniformly shaking, and inserting a glass funnel into each triangular flask; (2) putting all the triangular flasks into an iron reagent tray, putting the tray with the sample into a drying oven, keeping the temperature of120 DEG C, drying for 2 hours, taking out the tray from the drying oven, cooling, directly washing the small funnel with water, and washing the triangular flasks with washing liquor so that the totalvolume of the solution in the triangular flasks is controlled to be 50-60mL; and (3) adding three drops of phenanthroline indicator, titrating the residual K2Cr2O7 by using a ferrous sulfate standardsolution, and enabling the color change process of the solution to be orange yellow-blue green-brownish red. According to the method, digestion liquid in the test tube does not need to be washed out,the defects in the prior art do not exist, organic matter in soil can be detected on a large scale, operation is easy, environment friendliness and high efficiency are achieved, and safety and reliability are achieved.

Description

technical field [0001] The invention relates to the field of organic matter detection, in particular to an inspection and detection method for organic matter content in soil. Background technique [0002] The content of soil organic matter is an important index to measure soil fertility, and the fixation and change of soil organic carbon are related to the change of atmospheric carbon dioxide concentration. Therefore, rapid and accurate determination of soil organic matter content is the key to obtain soil fertility changes and soil organic carbon fixation, which is of great significance in evaluating soil fertility and slowing down the rise of atmospheric carbon dioxide concentration. [0003] There are many methods for soil organic matter detection, the common ones are oil bath and sand bath methods, the most widely used is the high temperature external heat potassium dichromate oxidation-volume method, such as the method provided by the industry standard NY / T1121.6-2006: ...

AI Technical Summary

Problems solved by technology

[0004] However, there are many defects in the above-mentioned method, such as (1) transferring the poaching liquid and soil residue in the test tube into a 250mL triangular flask without damage, so there is one more link, and the steps are cumbersome, (2) the wire cage is removed from the bath Take it out and cool it for a while, wipe the oil (wax) liquid outside the test tube with a lot of newspapers, which is not environmentally friendly. (3) The workload is heavy. Before each measurement, it is necessary to clarify the amount of chloride ions contained in the soil. Based on chlorine Only the content of ions can determine the amount of silver sulfate to be added, and the operation is more troublesome, and batch detection is inconvenient. (4) The oil bath oxidation of soil organic matter is very troublesome to operate. First, the temperature of the electric furnace must be controlled to prevent the solution from boiling violently. , (paraffin) oil is easy to splash on the inspectors, there are potential safety hazards, and the temperature of the electric furnace is difficult to control, (5) the highest degree of oxidation of organic matter by the potassium dichromate-concentrated sulfuric acid external heating method is only 95%, which cannot be achieved Complete oxidation of organic matter, the result will have errors

Images