Oxidation of soil pH soil tests to detect //

 Shenzhen set of universal soil soil potassium content detection detect soil PH value content detection set of universal Chen: 180-2871-9379 means a soil test is the best way to analyze the correlation between test results and determined to prove by field crops. Due to advances in soil science test by chemical analysis and the development of chemical and physical analysis of modern instrumental analysis. A successful soil testing methods, biological experiments and field must seek after a very clear correlation can be established. Soil testing techniques have been used in the recommended fertilization, soil testing and fertilizer is soil testing techniques specific application. Methods available nutrient content and some chemical properties of soil and plant nutritional status is closely related to the rapid determination. Usually includes quick result of nitrogen, phosphorus, potassium and soil pH and lime requirement relating to soil and other projects; some trace elements are sometimes included in the test range. Soil testing is a systematic process by collecting test samples, testing and application of the test results and other steps constituted. And with reference to other relevant information, you can make the evaluation of soil fertility status based on soil test results, which provide a basis for rational fertilization. Soil samples were collected from the field is beginning to work the soil test. Because of the soil, especially in the chemical composition of the soil tillage there is a huge difference in a different location, select a representative sample of the soil to become soil test results determine the reliability of the important part. Usually multi-point sampling methods, i.e., the plots within a predetermined sampling unit or a select number of sampling points sampled. With the size of the sampling area number of sampling points, the degree of complexity of the terrain and soil conditions vary, the general should be no less than 10 to 20. Sampling of topsoil to a depth limit, usually from 0 to 15 cm or 0-20 cm. Soil samples were collected at each sampling point to be mixed, for testing. Soil test methods and laboratory soil properties due to different conditions, but since the 1970s has a tendency to become more unified. The main test items are: ① Determination of soil available nitrogen. Soil available nitrogen in the soil refers to ammonium and nitrate content and low volatility, thus far lack the ideal measurement method. China often amount hydrolysis nitrogen as indicators of soil N-supplying capacity. ② soil phosphorus and potassium determination. Soil phosphorus and potassium extraction solvent extraction often measured. Because soil solution available phosphorus, potassium and phosphorus in soil adsorption state was between potassium establish a certain balance, so with the extraction agent extracted available phosphorus and potassium soil available only part of the total amount of potassium, it has can clearly reflect the total phosphorus, and potassium. Currently measuring acidity of soil phosphorus extraction method is generally used ammonium fluoride or double acid method. Determination of neutral and calcareous soil phosphorus extracted with sodium bicarbonate solution and more. Extraction of potassium to neutral ammonium acetate solution is more common. ③ pH and lime requirement of measuring soil. Soil pH is a strength index of soil acidity, soil solution with the negative logarithm of the hydrogen ion concentration, said. on behalf of the acidic pH of less than 7:00; pH greater than 7 on behalf of alkaline; pH 7 or neutral. Soil pH is generally measured with a glass electrode pH meter, because the water will affect the dilution ratio of soil and dissociation of hydrogen ions, and therefore the provisions of soil water than with a 1: 1 or 1: 2. PH can also be determined by analyzing the changes in the salt content of the soil. Soil lime requirement, means that under field conditions will raise the soil pH to a value suitable for the needs of a crop that must be added to the amount of lime substance. Different crops suitable pH varies, lime requirement is different. Generally based on the total acidity of soil, which is calculated based on the hydrogen ion concentration in the soil solution and soil particles and adsorption of hydrogen ions. Multi buffer solution balance method, the soil acidity is neutralized in a relatively short time and reached equilibrium, then the buffer solution and soil separated by standard alkaline titration to the original buffer solution pH. Can also be directly measured equilibrium solution pH, buffer solution pH changes can be used as an indicator of the lime requirement