1. A method for detecting soil fertility, which is characterized by comprising the following steps: the method comprises the following steps:

(1) selecting a piece of soil needing to be detected for fertility, enclosing a square land of which the length is 10 meters multiplied by 10 meters, and respectively taking cylindrical soil samples at four corners and the central point of the square land;

(2) wrapping and fixing the cylindrical soil sample obtained in the step (1) by using a steel wire gauze to prevent the soil sample from deforming or breaking, and saturating and spraying the wrapped and fixed soil sample by using deionized water;

(3) placing a certain amount of NaCl on the upper surface of the soil sample treated in the step (2), spraying the NaCl on the upper part of the soil sample by using a shower nozzle after placing, placing a collecting container below the soil sample to collect a water sample, and collecting the water sample once every ten minutes;

(4) numbering the water samples collected in the step (3), detecting the concentration of C1 & lt- & gt in the water samples by adopting an ion analyzer until the C1 & lt- & gt cannot be detected in the water samples, stopping collecting and detecting the water samples, and obtaining the pore volume of the soil through the total time and the C1 & lt- & gt leaching amount of collecting the water samples, so that the storage capacity of the soil on nutrients is obtained, and the fertility of the soil is reflected.

The method for detecting the fertility of the soil is suitable for zonal soil or mature farmland soil.

2. The method for detecting fertility of soil according to claim 1, wherein the step (1) comprises sampling the soil with a steel hollow cylinder having a diameter of 15cm and a length of 50 cm.

3. The method for detecting soil fertility according to claim 1 or 2, wherein the amount of NaCl in step (3) is 1 g.

4. The method for detecting soil fertility of claim 3, wherein the shower head in step (3) is used to shower water at a rate of 0.1-0.5 m/s.

5. The method for detecting soil fertility of claim 4, wherein the amount of the collected water sample per time in the step (3) is 20 ml.

Background

Soil environment monitoring means that the environment quality (or pollution degree) and the change trend thereof are determined by measuring representative values of factors affecting the soil environment quality. Soil monitoring generally refers to soil environment monitoring, and generally comprises technical contents of distribution sampling, sample preparation, analysis methods, result characterization, data statistics, quality evaluation and the like. In the prior art, the detection of the soil fertility is mainly judged by looking at the color of the soil, the depth of a soil layer, the soil tiltability, the soil slurry property and cracks, the method is only a qualitative detection method, and a quantitative detection result is not available for the soil fertility, so that the accuracy of the detection result is not high, and the detection result is greatly influenced by human subjective factors. The soil pores can reflect the storage capacity of soil to water, nutrients, salt, colloid and pollutants in the soil, and if the soil pores are large and numerous, the water and the nutrients in the soil are easy to run off, so that the indexes of the pores in the soil directly reflect the fertility of the soil.

Disclosure of Invention

In view of the defects of the background art, the invention provides a method for detecting soil fertility, which is used for detecting the soil fertility by quantitative analysis of pores in soil, is simple, has quantitative data results, and can detect the soil fertility more accurately and intuitively.

Therefore, the invention is realized by adopting the following scheme:

a method for detecting soil fertility, which is characterized by comprising the following steps: the method comprises the following steps:

(1) selecting a piece of soil needing to be detected for fertility, enclosing a square land of which the length is 10 meters multiplied by 10 meters, and respectively taking cylindrical soil samples at four corners and the central point of the square land;

(2) wrapping and fixing the five cylindrical soil samples obtained in the step (1) by using a steel wire gauze to prevent the soil samples from deforming or breaking, and saturating and showering the wrapped and fixed soil samples by using deionized water;

(3) placing a certain amount of NaCl on the upper surface of the soil sample treated in the step (2), spraying the NaCl on the upper part of the soil sample by using a shower nozzle after placing, placing a collecting container below the soil sample to collect a water sample, and collecting the water sample once every ten minutes;

(4) numbering the water samples collected in the step (3), and detecting Cl in the water samples by adopting an ion analyzer^-Until no Cl can be detected in the water sample^-Stopping collecting and detecting water sample, by the time and Cl of collecting water sample^-The leaching amount is obtained from the pore volume of the soil, so that the storage capacity of the soil for nutrients is obtained, and the fertility of the soil is reflected;

(5) the method is adopted to respectively obtain the time and Cl of collecting water samples of five soil samples^-The amount of leaching was averaged to reflect the fertility of the soil.

The method for detecting the fertility of the soil is suitable for zonal soil or mature farmland soil.

In the above method, the shorter the total time for collecting the water sample, the Cl^-The less the leaching amount, the more fertile the soil.

Further, a steel hollow cylinder with the diameter of 15cm and the length of 50cm is adopted in the step (1) for sampling soil;

further, the amount of NaCl in the step (3) is 1 g;

further, the water outlet speed of the shower nozzle in the step (3) is 0.1-0.5 m/s;

further, the amount of the water sample collected in each time in the step (3) is 20 ml.

Has the advantages that:

the invention provides a method for detecting soil fertility, which is suitable for zonal soil or mature farmland soil and is used for detecting the soil fertility by quantitative analysis of pores in the soil.

Detailed Description

The technical solutions of the present invention are described in further detail below, but the scope of the present invention is not limited to the following.

Example 1

A method for detecting soil fertility, which is characterized by comprising the following steps: the method comprises the following steps:

(1) selecting a piece of soil of the brown soil, enclosing a square land with the length of 10m multiplied by 10m, respectively taking cylindrical soil samples at four corners and the central point of the land, and taking the soil samples by adopting a steel hollow cylindrical barrel with the diameter of 15cm and the length of 50cm during sampling;

(2) wrapping and fixing the five cylindrical soil samples obtained in the step (1) by using a steel wire gauze to prevent the soil samples from deforming or breaking, and saturating and showering the wrapped and fixed soil samples by using deionized water;

(3) placing 1g of NaCl on the upper surface of the soil sample treated in the step (2), spraying the NaCl on the upper part of the soil sample by using a shower nozzle after placing, wherein the flow rate of water flow is 0.2m/s, placing a collecting container below the soil sample to collect a water sample, collecting every ten minutes, and collecting 20ml of NaCl every time;

(4) numbering the water samples collected in the step (3), and detecting Cl in the water samples by adopting an ion analyzer^-Until no Cl can be detected in the water sample^-Stopping collecting and detecting the water sample, obtaining the time and Cl of finally collecting the water sample^-The leaching amount is used for reflecting the fertility of the soil;

(5) the time for collecting the water samples of the five soil samples obtained by the method is Cl^-Leaching amount, the average value of the time for collecting the water sample is 500 minutes, Cl^-The average amount of leaching was 300 mg. .

Example 2

A method for detecting soil fertility, which is characterized by comprising the following steps: the method comprises the following steps:

(1) selecting a piece of yellow brown soil, enclosing a square land with the length of 10m multiplied by 10m, respectively taking cylindrical soil samples at four corners and the central point of the square land, and taking the soil samples by adopting a steel hollow cylindrical barrel with the diameter of 15cm and the length of 50cm during sampling;

(2) wrapping and fixing the five cylindrical soil samples obtained in the step (1) by using a steel wire gauze to prevent the soil samples from deforming or breaking, and saturating and showering the wrapped and fixed soil samples by using deionized water;

(3) placing 1g of NaCl on the upper surface of the soil sample treated in the step (2), spraying the NaCl on the upper part of the soil sample by using a shower nozzle after placing, wherein the flow rate of water flow is 0.2m/s, placing a collecting container below the soil sample to collect a water sample, collecting every ten minutes, and collecting 20ml of NaCl every time;

(4) numbering the water samples collected in the step (3), and detecting Cl in the water samples by adopting an ion analyzer^-Until no Cl can be detected in the water sample^-Stopping collecting and detecting the water sample, obtaining the time and Cl of finally collecting the water sample^-The leaching amount is used for reflecting the fertility of the soil;

(5) the time for collecting the water samples of the five soil samples obtained by the method is Cl^-The leaching amount is obtained by calculating the average value of the time for collecting the water sample to be 620 minutes, and Cl^-The average amount of leaching was 410 mg.

The foregoing is illustrative of the preferred embodiments of this invention, and it is to be understood that the invention is not limited to the precise form disclosed herein and that various other combinations, modifications, and environments may be resorted to, falling within the scope of the concept as disclosed herein, either as described above or as apparent to those skilled in the relevant art. And that modifications and variations may be effected by those skilled in the art without departing from the spirit and scope of the invention as defined by the appended claims.