Soil nitrate nitrogen extracting agent and method for rapid determination of soil nitrate nitrogen

Abstract

The invention relates to a soil nitrate nitrogen extracting agent and a method for rapid determination of soil nitrate nitrogen. The soil nitrate nitrogen extracting agent is a KCl aqueous solution with the concentration of 0.5-0.8mol/L; in the determination method, the KCl aqueous solution is adopted as the extracting agent for extraction in a ratio of water to soil of 5-10mL to 1g, a standard curve is made, the color comparison is carried out and then the calculating is carried out. The low-concentration KCl aqueous solution is used as the soil nitrate nitrogen extracting agent, so that the extracting effect is good and the detection result is accurate; besides, detection chemicals can be greatly saved, the detection cost is saved and the adverse effect on the environment can be reduced.

Description

technical field [0001] The invention relates to the technical field of agrochemical analysis, in particular to a soil nitrate nitrogen extraction agent and a rapid determination method for the nitrate nitrogen content in soil. Background technique [0002] In current agricultural production, the determinant of soil nutrient balance is the level of fertilizer input. In general, increasing the input of nitrogen fertilizer is beneficial for crops to absorb and assimilate more nitrogen, increase yield, and improve the quality of food crops. However, the uptake and assimilation of nitrogen by crops does not change synchronously with the nitrogen application rate. Usually, with the increase of nitrogen application rate, the apparent utilization rate of nitrogen decreases, the soil residue increases, and accumulates in the soil in the form of nitrate nitrogen, which poses a threat to environmental safety. Nitrate nitrogen in soil has always been a research hotspot in soil science...

AI Technical Summary

Problems solved by technology

But for a long time, the ultraviolet spectrophotometry is to use a higher concentration of potassium chloride solution as the soil leaching agent to extract the nitrate nitrogen in the soil, and it is considered that the concentration of nitrate nitrogen extracted by 2mol / L potassium chloride solution It is the closest to the actual situation in the field, but applying this extraction method to measure large quantities of samples not only needs to consume a large amount of expensive analytically pure potassium chloride reagent, but also the used potassium chloride solution enters the soil or The water bodies of rivers and lakes will also pose a threat to the environment, which has become one of the main factors restricting the popularization of this method; and the high-concentration potassium chloride salt solution is easy to cause corrosion to detection instruments and equipment during use.

[0004] For a long time, agrochemical workers have been eager to improve the method of measuring nitrate nitrogen by ultraviolet spectrophotometry, expecting to greatly reduce the detection cost on the basis of ensuring detection accuracy and accuracy, but no significant progress has been made

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