JPS615734A - Leaching control method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a leaching control method for removing soil salinity by sprinkling water for beam ching. The present invention relates to a method for controlling gluing by sprinkling water for gluing.

[Conventional technology]

In the field, trace amounts of salt in the irrigation water accumulated in the soil)
As the groundwater level rises, salt may precipitate near the surface, making it impossible to plant crops. As a countermeasure to this problem, there is a method of installing well-drained underground drainage facilities and spraying water to wash away the soil salts underground (leaching method). Among these, the former requires a considerable amount of facility costs, and therefore various leaching methods are used. However, the conventional leaching method only involves periodically sprinkling excess water on the field after the agricultural off-season, and is carried out without fully grasping the soil salinity condition. The reality is that there is no confirmation whether sufficient removal has been done.

[Problem that the invention seeks to solve]

The present invention has been made in view of the above-mentioned circumstances, and it is possible to constantly grasp the salt concentration contained in the water sampled from the soil, and to spray the necessary amount of leaching method to reduce the soil salt. The object of the present invention is to provide a leaching control method that can wash away leaching to a necessary extent and sufficiently.

[Means for solving problems]

The configuration of the present invention that has achieved the above object is that in a leaching method that removes soil salinity by spraying leaching water, a sampling water collection pipe is buried in the soil to sample moisture in the soil. At the same time, the salinity concentration in the sampled water is compared with a predetermined reference salinity concentration, and the amount of spraying water for leaching is controlled based on the difference between the two.

[Effect]

Since the salinity concentration in the soil is compared with the predetermined standard salinity concentration, it is possible to grasp the current salinity concentration in the soil, and the salinity can be used to appropriately control the irrigation water. The required amount of leaching water can be sprayed by If the number of samples is increased, the average salinity concentration in the area concerned and furthermore the dispersion of the salinity concentration can be determined, so it is possible to control the amount of leaching water by changing the pattern of spraying water.

〔Example〕

FIG. 1 is a partially cutaway explanatory diagram illustrating the configuration of a field to which the present invention is applied. In the figure, a leaching water supply pipe 2 is provided on the ground surface of a field 1. A plurality of branch pipes 2a connected to the supply pipe 2 at appropriate intervals are respectively arranged on the ground surface of the field 1, and configured so that leaching water is sprayed by a plurality of sprinklers 9 provided on the branch pipes. has been done. The pump 3 connected to the supply pipe 2 is connected via a drive motor M to a control computer 4, which will be described later, and is configured to be turned on and off by signals output from the computer 4. Further, a perforated pipe 5 having a large number of water introduction holes 5a is buried at an arbitrary position in the soil, and a discharge side end 5b of the perforated pipe 5 is connected to a drainage ditch 6. A water collection basin 7 is provided near the outlet of the drain groove 6, in which the waste water from the drain port 6 is collected. A salinity analysis sensor 8, one end of which is connected to the computer 4, is installed in the water collection chamber 7, and the detection end is immersed in the collected wastewater. It is configured to send information on the salt concentration to the computer 4.

Since the leaching water actually used may also contain some salt, in this embodiment, another salinity analysis sensor 8a is installed in the leaching water supply pipe 2 to cope with such cases. ing.

A flow meter 10a is installed in the leaching water supply pipe 2, and a flow meter 10b is installed in the draining water of the water collection basin 7 so that the amount of drainage can be detected. The salinity analysis sensor 8a, flowmeter 10a, and flowmeter 10b are also connected to the computer 4, respectively, and are configured to be able to send the obtained information signals. These information signals are input to the computer 4 and are used as arithmetic processing information.

FIG. 2 shows the configuration of a computer used in the method of the present invention. In the figure, the information signal J (salt concentration of wastewater) sent from the salinity analysis sensor 8 is input to the input/output section I/Q. In addition, an information signal Kl (salt concentration of water for cleaning) sent from the salinity analysis sensor 8a and a flow meter 10a
Information signal La (water supply amount) sent from the flowmeter 10b
The information signal Lb (displacement amount) sent from the input/output section I
10 is input. These data are sequentially input to the calculation unit RAM and subjected to calculation processing. On the other hand, information signal P
By inputting (the soil's critical salinity concentration) into the memory (partial ROM) in advance, calculations and condition comparisons are performed within the set conditions, and based on the results, commands are sent to relay circuit R to turn the drive motor ON or OFF. It has the ability to emit.

Next, FIG. 3 is a flowchart of timing control of beam water. The operating procedure will be explained below with reference to FIG. When spraying water for leaching, first, an information signal P (soil's critical salinity concentration) is input to the computer 4 (FIG. 2).

The critical salinity concentration of soil is a value that differs depending on the nature of the soil and the crops grown in that soil, and is a standard value that can be selected for the field and determined in advance. A concentration that does not adversely affect crops is determined by matching the salt concentration in the water. When the spraying of a certain amount of leaching water is started, the salinity analysis sensor 8a first detects the salinity concentration (6) of the leaching water and sends it to the computer 4. Sprinkler on the other hand
The leaching water sprayed from step 9 permeates into the soil and washes away the salt. Drainage water that has been washed away with salt is passed through the water introduction hole 5.
It flows into the perforated pipe 5 from a, flows out to the drainage ditch 6, and is then collected in the water collection basin 7.

A salinity analysis sensor 8 detects the salt concentration (J) in this wastewater. The information signal J sent to the computer 4 is inputted from the input/output section I10 to the calculation section RAM together with the previously input salinity concentration (6) of the leaching water, and the difference in salinity concentration between the two is calculated. (i) This calculation calculates the salt concentration of wastewater by subtracting the salt concentration contained in the leaching water. Continuation operation part RA
The supplied water amount information signal (La) and the drainage amount information signal (Lb) are input to M, the difference in the supplied water amount is calculated, and the soil salinity concentration is converted from this value and the previously calculated salt content concentration of the drainage water. do. The soil salinity obtained in this way is compared with the information signal TE) of the critical salinity that was input in advance, and if it is less than the soil salinity and the critical salinity Φ), the signal is output to the relay circuit R. When the drive motor M is stopped, the supply of water for ching is stopped. Conversely, if the soil salinity is higher than the critical salinity (P), the amount of leaching water to be further supplied is calculated from the difference between the two, and the leaching time (extension time) required for it is calculated.

Continue leeching during the extra time calculated in this way,
A stop signal is output and the supply of leaching water is stopped. Then, it is compared again with the information signal (P) of the critical salinity concentration, and if it is less than that, leaching is finished, and if it is more than that, leaching is started again.

According to this embodiment, the soil salinity in the field can be accurately grasped at all times, and the most appropriate and necessary leaching can be automatically performed, and the soil salinity value used for this control is This is the average soil salinity based on the average wastewater salinity obtained from. In addition, there is no wastage of water for leaching, and although underground drainage facilities are provided in some areas to collect wastewater for sampling, it is economically advantageous to provide underground drainage facilities throughout the field. In this example, an example was shown in which the salinity concentration in the water supply and the amount of the water supply were measured and the soil salinity was calculated from the measurement results. It is also possible to compare the value with a predetermined critical salinity concentration value.

〔Effect of the invention〕

Since the present invention is constructed as described above, it is an object of the present invention to provide a leaching control method that can constantly grasp the salinity concentration of soil and spray a necessary amount of leaching water to sufficiently wash away soil salinity to a necessary extent. was completed.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway explanatory diagram illustrating a field to which the present invention is applied, FIG. 2 is an explanatory diagram illustrating the configuration of a computer used in the present invention, and FIG. 3 is a flowchart showing the operating procedure of the method of the present invention. be.

Claims (1)

[Claims] In the leaching method in which soil salinity is removed by spraying leaching water, a sampling water collection pipe is buried in the soil to enable sampling of moisture in the soil, and the salinity concentration in the sampled moisture is determined in advance. A leaching control method characterized by comparing the obtained standard salinity concentration with the reference salinity concentration and controlling the amount of leaching water to be sprayed based on the difference between the two.