JP2001128523A - System for cleaning up farm environment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a farm environmental clean-up system for preventing pollution of ground water by controlling the amount of fertilizer through the ground water and a farm environmental clean-up system to plan to prevent ground water pollution by realizing reuse of the fertilizer dissolved into the ground water. SOLUTION: A fertilizer is reused by installing a detection means (a fertilizer detector 26) for detecting a fertilizer concentration in ground water of a farm (2) and a calculation means (a controller 28), calculating to forecast the amount of fertilizing to a farm by using a detected value of fertilizer concentration and the amount of fertilizer as calculating information, or storing ground water in a water storing means (a ground water tank 12) by collecting the ground water by a water-collecting means (culverts 6, draining pipes 8, water-collecting pipes 10) and supply water to the farm by a water feed means (water supply pipes 40) when the detected value of the fertilizer concentration is larger than the standard value. Thus, the ground water pollution and reuse of the fertilizer, i.e., nitrate nitrogen dissolved into ground water are realized by controlling the fertilizing amount through the ground water.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a field environment purification system used for preventing groundwater contamination due to fertilization in a field such as a tea plantation where tea is grown.

[0002]

2. Description of the Related Art Fertilizers administered to tea gardens are decomposed into ammonia nitrogen by microorganisms in the ground, and this ammonia nitrogen is further decomposed into nitrate nitrogen (nitrate nitrogen), and part of the fertilizer is converted into tea trees. Fertilizers that are absorbed but not absorbed by the tea plant remain in the ground or gradually run off into groundwater,
The runoff becomes significant during rainfall.

[0003]

By the way, most of the fertilizer that is not absorbed by the tea plant flows into rivers, ponds and the like through groundwater, and much of the fertilizer applied is wasted. Slow-release fertilizers have been used, but they cannot prevent runoff into groundwater.

Accordingly, a first object of the present invention is to provide a field environment purification system for preventing contamination of groundwater by controlling the amount of fertilization through groundwater.

[0005] It is a second object of the present invention to provide a field environment purification system that realizes the reuse of fertilizer that has flowed into groundwater to prevent groundwater contamination.

[0006]

SUMMARY OF THE INVENTION The present invention relates to a detecting means (fertilizer detector 2) for detecting the concentration of fertilizer in groundwater in a field (2).
6) and a calculating means (control device 28) for predicting and calculating the amount of fertilization to be administered to the field using the detected value of the fertilizer concentration and the amount of fertilization as the calculation information, or a water collecting means (underdrain 6, suction pipe 8. Collecting groundwater by the water collecting pipe 10) and storing it in the water storage means (groundwater tank 12), and when the detected value of the fertilizer concentration is equal to or higher than the reference value, water is supplied to the field by the water supplying means (water supply pipe 40). Reuse. As a result, by controlling the amount of fertilization through the groundwater, it is possible to prevent the contamination of the groundwater and to reuse the fertilizer flowing out into the groundwater, that is, the nitrate nitrogen.

In order to achieve the first object, the field environment purification system of the present invention according to claim 1 has a detecting means (fertilizer detector 26) for detecting the concentration of fertilizer in groundwater in the field (2).
And a calculating means (control device 28) for predicting and calculating the amount of fertilization to be administered to the field using the detection value of the detecting means and the amount of fertilization applied to the field as calculation information. I do.

[0008] That is, the concentration of fertilizer in groundwater is the amount of fertilizer runoff and depends on the amount of fertilizer applied and the amount of plant absorption in the field. Therefore, the optimum fertilizer amount is predicted and calculated from the relationship between the fertilizer concentration in the groundwater and the fertilizer amount which will be proportional to the runoff amount. That is, by observing the relationship between the fertilization amount and the runoff amount, a certain functional relationship can be found, and the optimum fertilization amount can be calculated from this relationship. In this case, variables depending on the amount of rainfall and the growth state of the plant are also taken into account. Therefore, by realizing the optimal amount of fertilizer, waste of fertilizer can be eliminated and groundwater contamination by fertilizer can be reduced.

According to a second aspect of the present invention, in order to attain the second object, a single or a plurality of water collecting means (underdrain) buried underground to collect groundwater (25). 6, water absorption pipe 8, water collection pipe 10), water storage means (groundwater tank 12) for storing the groundwater collected by the water collection means, and detection means (fertilizer detector 26) for detecting the fertilizer concentration of the groundwater. And a water supply means (water supply pipe 40) for supplying the groundwater from the water storage means to the field (2) when the detection value of the detection means is equal to or more than the reference value.

A groundwater collecting means is buried underground to collect groundwater, and the groundwater is stored in a water storage means. Detect the fertilizer concentration in the groundwater, and if the fertilizer concentration is above the reference value,
The fertilizer in the groundwater is reused by feeding the groundwater from the water storage means to the field. That is, the runoff nitrate nitrogen can be collected through groundwater and reused as fertilizer. Therefore, excessive fertilizer administration can be prevented, and pollution of groundwater can be prevented.

According to a third aspect of the present invention, there is provided a field environment purification system according to the present invention, wherein water collecting means (underdrain 6, water suction pipe 8, water collecting pipe 10) which is buried underground to collect groundwater (25); A water storage means (groundwater tank 12) for storing the groundwater collected by the water means, a detection means (fertilizer detector 26) for detecting the fertilizer concentration of the groundwater, and a detection value of the detection means being equal to or more than a reference value. In this case, a switching means (valve 34) for storing the groundwater in the water storage means and discharging the groundwater when the detection value of the detection means is less than a reference value is provided.

In this field environment purification system, water is stored or discharged depending on the concentration of fertilizer in groundwater to be collected. That is, when the fertilizer concentration of the groundwater is less than the reference value, the groundwater is not polluted, so the water is discharged as it is, and when the fertilizer concentration is the reference value or more, the fertilizer is collected in the water storage means and reused. . That is, the groundwater in the water storage means is supplied to the field by the water supply means. Therefore, the use of groundwater can prevent the administration of excessive fertilizer, and can prevent the contamination of groundwater. In addition, when the concentration of fertilizer is low, even if water is discharged, the groundwater is not contaminated.

According to a fourth aspect of the present invention, there is provided a field environment purification system according to the present invention, wherein a water collecting means (underdrain 6, water suction pipe 8, water collecting pipe 10) which is buried underground to collect groundwater (25); A water storage means (groundwater tank 12) for storing the groundwater collected by the water means, and a concentration means (separation membrane 46) for concentrating the groundwater stored in the water storage means and converting the groundwater to a concentrated water having a high fertilizer concentration. A water supply means (water supply pipe 40) for supplying the concentrated water of the water storage means to a field.

The collected groundwater is stored in a water storage means, the groundwater is concentrated and converted into concentrated water having a high fertilizer concentration, and the concentrated water is supplied to a field, whereby the fertilizer can be reused. It is possible to prevent excessive fertilizer administration and pollution of groundwater.

According to a fifth aspect of the present invention, in the field environment purification system of the present invention, a filter means (separation membrane 46) for filtering the groundwater of the water storage means, and a water discharge means (water discharge means) for discharging the groundwater filtered by the filter means. Valve 50). That is, by filtering the groundwater collected and stored in the water storage means by the filtration means, it is possible to recover the fertilizer that has flowed out, and to prevent the contamination of the groundwater by discharging the filtered groundwater. .

According to a sixth aspect of the present invention, there is provided a field environment purification system according to the present invention, wherein the purification means (separation membrane 46) for purifying the groundwater of the water storage means, and the water discharge means for discharging purified water purified by the purification means. Valve 50). That is, the groundwater collected and stored in the water storage means is purified by the purification means, and the discharged water is discharged, thereby preventing the contamination of the groundwater.

According to a seventh aspect of the present invention, in the field environment purification system according to the present invention, a porous pipe (24) for selectively collecting the groundwater is used as the water collecting means. That is, the fertilizer can be collected together with the groundwater by burying the porous tube in the ground.

The field environment purification system of the present invention according to claim 8 is characterized by comprising a transmission means (transmitter 32) for transmitting the fertilizer concentration detected by the detection means. In other words, when the field and the field manager are separated, by transmitting information such as fertilizer concentration using a communication medium such as a telecommunication line or wireless communication by a transmission means installed in the field, the field can be easily managed. And speeding up.

The field environment purification system of the present invention according to claim 9 is characterized in that the water supply means includes a pumping means (pump 36) for pumping the groundwater to the field. That is, by providing the pumping means, it is possible to supply water with a desired water pressure to a field having a large height difference.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings.

FIG. 1 shows a fertilizer application management system according to a first embodiment of the field environment purification system of the present invention. Taking a tea plantation where a tea tree 4 is cultivated in the field 2 as an example, the field 2 is a so-called terraced field in which narrow plane portions 2A, 2B, 2C,. Each plane part 2A-2C
Fertilizer is applied to the tea plant 4, which is a cultivated plant planted in the area, as necessary. And, in each of the plane portions 2A to 2C,
As underground water collecting means, culverts 6 are individually formed, and each water absorption pipe 8 buried in each culvert 6 is connected to a water collecting pipe 10. The water collecting pipe 10 is laid underground in the field 2. Therefore, as shown by the arrow A, the groundwater in the field 2 is collected in the water collection pipe 10 through the water suction pipe 8 of the culvert 6, and is guided to the groundwater tank 12 as a water storage means.

As shown in FIG. 2, each of the culverts 6 has a width of 60 cm on the plane portions 2A to 2C of the field 2 and is 1-2 cm from the ground surface 16.
The water-absorbing pipe 8 laid in the trench is covered with a water-permeable material 18 such as rubble, and soil 20 is laid on the water-absorbing pipe 8. The water absorption tube 8 is formed of a corrosion-resistant material such as a synthetic resin. For example, as shown in FIG. 3, a porous tube 24 having a plurality of water absorption holes 22 is used. The water-permeable material 18 has a function of preventing the water-absorbing through holes 22 from being clogged. Therefore, as shown in FIG. 2, only the groundwater 25 is selectively absorbed into the water absorption pipe 8.

The groundwater supplied through the culvert 6 is
As shown in FIG. 4, the water is collected in a single or a plurality of water collecting pipes 10, and guided to a groundwater tank 12 through the water collecting pipes 10.
In this case, in FIG. 4, the culvert 6 and the water suction pipe 8 are drawn horizontally, but the inclination of the field 2 is used to utilize the water collecting effect by gravity. Arrows indicate the state of collected groundwater.

The collecting pipe 10 reaching the groundwater tank 12 includes:
A fertilizer detector 26 as a fertilizer detecting means and a flow rate detector 27 as a flow rate detecting means are provided. Fertilizer detector 26
Is the condition of fertilizer components and groundwater, that is, PH, E
C _{value, NO 3 -N, NH 4 -N} , PO 4, K, Ca, M
It is a general term for various measuring instruments for measuring g and the like. The flow rate detector 27 detects the flow rate of groundwater collected by the water collecting pipe 10. A rain gauge 29 is provided as a means for detecting the amount of rainfall.

Each detection output of the fertilizer detector 26, the flow detector 27 and the rain gauge 29 is applied to a control device 28 as a calculating means and a control means as shown in FIG. The control device 28 is constituted by a personal computer or the like, and its output is applied to a display 30 and a transmitter 32. In this case, as for the detection output of the fertilizer detector 26, the administrator may add each detection value to the control device 28 through input means such as a keyboard. The control device 28 can calculate the amount of fertilizer runoff and the amount of soil fertilizer remaining (the amount of fertilization minus the amount of runoff) from the value detected by the fertilizer detector 26. That is, the fertilizer concentration in groundwater is the amount of fertilizer runoff, and depends on the amount of fertilizer applied and the amount of plant absorption in the field.
Therefore, from the relationship between the concentration of fertilizer in the groundwater and the amount of fertilization that will be proportional to the amount of runoff, it is possible to predict and calculate the optimal amount of fertilization. By obtaining the relationship between the amount of fertilization and the amount of runoff and observing the transition, it is possible to calculate the optimum amount of fertilization for the cultivated plant such as the field 2 and the tea plant 4. In this case, the fertilizer amount includes, in addition to the fertilizer, the tea tree itself cut at the time of autumn pruning, the fertilizer may also take into account variables such as rainfall and plant growth conditions. Achieving the optimal amount of fertilizer not only eliminates waste of fertilizer, but also suppresses groundwater contamination by fertilizer.

Here, the runoff amount of the fertilizer is A, and the fertilizer detector 26
Is the fertilizer concentration detected by the flow rate, the groundwater flow rate detected by the flow rate detector 27 is q, and the rainfall detected by the rain gauge 29 is r.
Then, the fertilizer runoff amount A is as follows: A = p × q = p × r (1) Note that a coefficient is applied to q because not all groundwater can be supplemented. Also, r has a decrease due to evaporation or the like. In addition, B is the amount of residual nitrogen in the soil according to tea growth, C is the amount of nitrogen absorbed in the tea tree according to tea growth, D is the nitrogen decomposition speed for each input fertilizer, and D is the amount of nitrogen generated based on this, and E is Indicates the input of fertilizer, and there are types and amounts of fertilizer to be input.
These are shown in a graph in FIG. In FIG. 5, the fertilizer runoff amount A is an actually measured value, the soil residual nitrogen amount B and the tea tree nitrogen absorption amount C are estimated values, and the nitrogen generation amount D is a predicted value by simulation. The amount of fertilizer runoff A is proportional to the concentration of fertilizer in the soil, and the amount of residual nitrogen B in the soil is larger as the tea tree absorbs more fertilizer, that is, the residual amount is required.

Therefore, the relationship among the amount of fertilizer runoff A, the amount of residual nitrogen B in the soil, the amount of nitrogen absorption C of tea plant and the amount of generated nitrogen D is such that D-B-A-C = 0 (2). Optimum fertilization can be realized by controlling the fertilizer input E. In this case, the amount of air released by nitrogen gas was omitted.

Incidentally, the soil residual nitrogen amount B can be measured by an EC sensor, a PF sensor, or the like.
With -B, the amount of absorption of the tea plant 4 can be set, and the nutritional diagnosis of the tea plant 4 can be made from the numerical value.

Since A is added to D and reused, it is possible to control the fertilizer input E so that DBC = 0.

The display 30 displays the detected value, the calculation result, and the like. In this case, when the fertilizer concentration detected by the fertilizer detector 26 is equal to or higher than a predetermined reference value, water discharge from the groundwater tank 12 is prohibited, and a warning is displayed to the manager to call attention. The groundwater stored in the groundwater tank 12 can be used as irrigation water or reused as fertilizer.

Next, FIG. 6 shows a fertilizer recovery and reuse system which is a second embodiment of the field environment purification system of the present invention. Also in this embodiment, a tea garden in which a tea plant 4 is cultivated in the field 2 is taken as an example. The field 2 is a so-called terraced field in which the narrow plane portions 2A, 2B, 2C,... Form a step shape, and the tea plant 4 which is a cultivated plant planted on each of the plane portions 2A to 2C is provided as necessary. Fertilization is performed. In each of the flat portions 2A to 2C, a culvert 6 is formed individually for collecting groundwater, and each water absorption pipe 8 buried in each culvert 6 is connected to a water collection pipe 10;
Is laid underground in the field 2. Accordingly, the groundwater in the field 2 is collected through the water intake pipe 8 of the culvert 6
And is led to the groundwater tank 12. The structure of the culvert 6 is shown in FIG. 2, the form of the water absorption pipe 8 is shown in FIG. 3, and the forms of the culvert 6, the water absorption pipe 8 and the groundwater tank 12 are as shown in FIG.

A fertilizer detector 26 is provided in the water collecting pipe 10 near the groundwater tank 12. The fertilizer detector 26 detects the condition of the fertilizer component and the groundwater, that is, the P of the groundwater.
H, EC _{value, NO 3 -N, NH 4 -N} , PO 4, K, C
It is a general term for various measuring instruments for measuring a, Mg, etc. The detection output of the fertilizer detector 26 is applied to a control device 28, and the control device 28 performs a comparison between the fertilizer concentration and a reference value as an operation related to the detection output.

In the water collecting pipe 10 immediately before the groundwater tank 12, a valve 34 as a switching means and a water discharging means is installed. That is, the switching control of the valve 34 is performed by the control device 28 as a control means. When the groundwater fertilizer concentration is equal to or higher than the reference value, the fertilizer is switched to the water storage side X to guide the groundwater to the groundwater tank 12 and the groundwater is reduced to a value less than the reference value. In this case, the water is switched to the water discharge side Y to discharge water to the outside.

A pump 36 is provided as means for pumping the groundwater stored in the groundwater tank 12, and the drive of the pump 36 is controlled by the controller 28. The groundwater pumped by the pump 36 is reused, guided from the groundwater tank 12 to each tea plant 4 through a water supply pipe 40 laid in the field 2, and used for irrigation and the like. Arrow B
Indicates pumping of groundwater.

With this configuration, the fertilizer that has flowed out of the field 2 due to precipitation or the like after fertilization is collected together with the groundwater through the water suction pipe 8 of the culvert 6 into the water collecting pipe 10. Water collecting pipe 10
Passes through the fertilizer detector 26, and the fertilizer concentration is detected. In this case, PH, EC value of groundwater,
_{NO 3 -N, NH 4 -N,} PO 4, K, Ca, Mg or the like,
The fertilizer concentration is measured. In some cases, the value cannot be ruled out to cause environmental pollution. Therefore, a preset reference value is compared with the detected fertilizer concentration. The result of the comparison is displayed on the display 30 and the transmitter 32
To the administrator at a remote location by wireless or telephone line. In this case, if the reference value is greatly exceeded, the display or warning is issued. The display 30 may be a visual display, an auditory display, or the like, and the measurement result or the calculation result may be recorded on a recording paper by a printer or the like.

As a result of the fertilizer concentration measurement, if the fertilizer concentration is less than the reference value, there is no risk of environmental pollution. Therefore, the valve 34 is switched to the water discharge side Y and discharged to a river or the like through the drain. In this case, the groundwater may be guided to the groundwater tank 12 and stored regardless of the fertilizer concentration of the groundwater.

As a result of the fertilizer concentration measurement, when the fertilizer concentration is equal to or higher than the reference value, the fertilizer can be reused as fertilizer. Since this groundwater contains reusable nitrate nitrogen, it is pumped together with the groundwater by a pump 36 and irrigated into the field 2 through a water supply pipe 40. As a result of this irrigation, nitrate nitrogen, which is a fertilizer component, is supplied to the field 2, and the shortfall that has flowed off due to precipitation can be supplemented. As a result, it is possible to prevent reuse of fertilizer and watering, and also prevent environmental pollution due to excessive fertilization.

Next, FIG. 7 is a block diagram showing a system for collecting and concentrating fertilizer from groundwater. This system collects the fertilizer that has flowed into the groundwater, concentrates the fertilizer concentration in the collected groundwater, and purifies the groundwater for irrigation or natural discharge.

The groundwater tank 12 stores the groundwater flowing through the water collection pipe 10. In this case, groundwater is stored regardless of fertilizer concentration. A water supply pipe 40 is connected to the groundwater tank 12 via the pump 36 in the system shown in FIG. A pump 44 as a pressurizing means is connected to the groundwater tank 12 via a filter 42 for removing impurities in the groundwater, and the groundwater is pressurized and sent to the separation membrane 46 through the pump 44.

The separation membrane 46 is a means for concentrating fertilizer, a means for filtering groundwater, or a means for purifying water.
This is a means for separating into groundwater with high fertilizer concentration, that is, condensed water and purified water, using a reverse osmosis membrane such as a membrane that does not transmit nitrate nitrogen ions. The condensed water flows from the separation membrane 46 to the groundwater tank 1
2, the purified water is supplied from the separation membrane 46 to the purified water tank 48 and stored therein. The purified water stored in the water purification tank 48 is naturally discharged through a valve 50 which is a water discharging means. That is, the drive of the pump 44 and the valve 50 is controlled by the control device 28 which is a control means,
Drives the groundwater in the groundwater tank 12 to separate the separation membrane 46.
Can be circulated to increase the fertilizer concentration. That is,
At the time of rainfall, fertilizers such as nitrate nitrogen diluted and run off in the groundwater are collected from the groundwater, and can be administered to the field 2 through the water supply pipe 40.

As the purified water tank 48, a tank having a smaller capacity than the underground water tank 12 is used, and natural discharge is possible by opening a valve 50 in accordance with the generation of purified water. Although the purified water is not shown, it can be supplied to the water supply pipe 40 side and used for irrigation in the field 2, and even if it is naturally discharged, it does not cause groundwater contamination and contributes to environmental purification.

By the way, regarding the administration of fertilizer in tea gardens, the product quality of green tea and the concentration of total nitrogen and free amino acids contained in crude tea are closely related. Efforts have been made to increase the total nitrogen and free amino acid levels in tea. As a result, large amounts of nitrogen fertilizers are normally used in tea cultivation, and problems such as strong acidification of the soil, weakening of the tree due to the death of the root system, contamination of groundwater by nitrate nitrogen, and generation of nitrous oxide gas are raised. As a result, nitrate nitrogen was added to the environmental standards for public water bodies and groundwater, and standards were set from the viewpoint of preventing environmental pollution. In other words, assuming that 1,000 tons of water flows out of the system from the tea plantation of 10a annually, only 10k of nitrogen can be released.
g.

From such a viewpoint, by recovering and reusing the fertilizer of the present invention, the nitrogen use efficiency of tea can be remarkably improved, and the nitrogen component flowing out is removed to meet the environmental standards. It was confirmed that it could be cleared. In particular, the use of slow-release fertilizers, etc. contributes to prevention of environmental pollution by nitrate nitrogen, purification of water quality, promotion of denitrification in lower soil, etc. in combination with the drastic extension of the residence time of fertilizer components in the root zone. be able to.

In order to remove nitrate nitrogen from the groundwater stored in the groundwater tank 12, instead of the method using the separation membrane 46, a physicochemical method such as an ion exchange method or a reverse osmosis method, and a reduction ability of microorganisms are used. A biological denitrification method or the like can be used. In the ion exchange method, ions in water to be removed are removed by exchanging with ions of an ion exchanger.To remove nitrate nitrogen, a strong basic anion exchange resin is usually used. I just need. In the reverse osmosis method, usually, of the solution on both sides of the semipermeable membrane,
It is known that water molecules move from a lower concentration to a higher concentration, but if a pressure higher than the osmotic pressure difference is applied to the higher concentration solution, on the contrary, the higher concentration lowers the concentration. By taking advantage of the phenomenon that water molecules migrate, nitrate nitrogen can be removed from groundwater.

The biological denitrification method is a method for removing nitrate nitrogen in water by the denitrification action of denitrifying bacteria. The denitrifying bacteria are fixed on a carrier so as not to diffuse into water. A carrier on which denitrifying bacteria are fixed is introduced into groundwater, or groundwater is passed through a carrier layer on which denitrifying bacteria are fixed to remove nitrate nitrogen. Microorganisms capable of denitrification are distributed in nature, and it is said that about 20% of anaerobic bacteria fall under this category.

In the field 2, a permeation barrier may be provided. This permeation barrier is a layer of a carrier on which microorganisms (denitrifying bacteria) are immobilized, and is installed in a portion above an aquifer below an upland area or a livestock area serving as a source of nitrogen components. That is, when the infiltration water containing nitrate nitrogen passes through the osmosis barrier, nitrate nitrogen is reduced to nitrogen gas by the denitrification action of the denitrifying bacteria, and the effect of blocking the permeation of nitrate nitrogen to a depth below the osmosis barrier is obtained. Can be expected. There are a conventional method and a horizontal well method for installing the permeation barrier. The former is a method in which the surface soil is once removed, the microorganism carrier is spread, and then the soil is refilled. The latter is a method of providing a plurality of horizontal wells and filling the wells with a microorganism carrier. In the horizontal well method, diagonal digging is started with a drill, and when it reaches a predetermined depth, it shifts to horizontal digging, and when horizontal digging reaches a scheduled point, the tip of the drill is turned obliquely upward and digging is performed. When the ground reaches the ground, there are various methods such as switching the tip to a reverse drill and finishing the well while drawing in the well tube filled with the carrier.

[0047]

As described above, according to the present invention,
The following effects can be obtained. a Since the fertilizer concentration in the groundwater in the field is detected and the fertilization amount can be set according to the cultivated plant or land in accordance with the detected value, waste of the fertilizer can be suppressed and groundwater contamination can be prevented. b. Since groundwater whose fertilizer concentration is lower than the reference value is discharged, it is possible to prevent groundwater contamination and contribute to environmental purification. c The fertilizer that has flowed to the groundwater can be recovered through the groundwater,
The groundwater can be used after being irrigated, and the amount of fertilizer applied can be reduced by reusing the collected fertilizer. d. The detected value of the concentration of fertilizer in groundwater can be transmitted to a field manager through a communication line or the like, so that the state of contamination of groundwater can be immediately known, thereby contributing to quick response required for prevention of groundwater contamination. e Since the burial of the culvert promotes drainage in the soil, by preventing excess water from floating on the surface, the oxygen supply to the roots of cultivated plants such as tea plants is improved, and the yield and quality of tea leaves and the like are improved. be able to.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a fertilization management system according to a first embodiment of a field environment purification system of the present invention.

FIG. 2 is a sectional view showing a form of a culvert.

FIG. 3 is a perspective view showing a perforated pipe as an embodiment of a water collecting pipe.

FIG. 4 is a diagram showing an embodiment of a culvert, a water collecting pipe, and a groundwater tank.

FIG. 5 is a diagram showing the relationship among fertilizer runoff A, soil residual nitrogen B, tea tree nitrogen absorption C, and nitrogen generation D.

FIG. 6 is a block diagram showing a fertilizer collection / reuse system which is a second embodiment of the field environment purification system of the present invention.

FIG. 7 is a block diagram showing a system for collecting and concentrating fertilizer from groundwater.

[Explanation of symbols]

 2 Field 4 Tea plant 6 Underdrain (water collecting means) 8 Water absorption pipe (water collecting means) 10 Water collecting pipe (water collecting means) 12 Groundwater tank (water storing means) 24 Perforated pipe 25 Groundwater 26 Fertilizer detector (detecting means) 28 Controller (Control means, calculation means) 32 Transmitter (transmission means) 34 Valve (switching means) 40 Water supply pipe (water supply means) 46 Separation membrane (concentration means, filtration means, purification means)

Claims (9)

[Claims] 1. A detection means for detecting the concentration of fertilizer in groundwater in a field, and a calculation for predicting and calculating a fertilization amount to be administered to the field using the detection value of the detection means and the fertilization amount administered to the field as calculation information. Means, comprising: a field environment purification system. 2. A single or plural water collecting means buried in the ground to collect groundwater, a water storage means for storing the groundwater collected by the water collecting means, and a fertilizer concentration of the groundwater is detected. And a water supply means for supplying the groundwater to the field from the water storage means when the detection value of the detection means is equal to or greater than a reference value. 3. A water collecting means buried in the ground to collect groundwater, a water storage means for storing the groundwater collected by the water collecting means, and a detecting means for detecting a fertilizer concentration in the groundwater. A switching means for storing the groundwater in the water storage means when the detection value of the detection means is equal to or more than a reference value, and discharging the groundwater when the detection value of the detection means is less than the reference value; And a water supply means for supplying the groundwater to the field from the following. 4. A water collecting means buried in the ground to collect groundwater, a water storage means for storing the groundwater collected by the water collecting means, and a condensing means for condensing the groundwater stored in the water storing means. And a water supply means for supplying the concentrated water of the water storage means to a field. 5. The field according to claim 1, further comprising: a filtering means for filtering the groundwater of the water storage means; and a water discharging means for discharging the groundwater filtered by the filtering means. Environmental purification system. 6. A purifying means for purifying the groundwater of the water storage means, and a water discharging means for discharging purified water purified by the purifying means. 4. The field environment purification system according to 4. 7. The water collecting means according to claim 1, wherein a perforated pipe for selectively collecting the groundwater is used.
5. The field environment purification system according to 3 or 4. 8. The field environment purification system according to claim 1, further comprising a transmission means for transmitting the fertilizer concentration detected by said detection means. 9. The field environment purification system according to claim 2, wherein the water supply means includes a pumping means for pumping the groundwater to the field.