CN106644596A - In-situ monitoring and sampling device for percolating water in farmland soil - Google Patents

Abstract

An in-situ monitoring and sampling device for farmland soil leakage water, comprising: an undisturbed soil holding cylinder, a leakage filter chamber, a diversion pipe, a water tank, a sampling pipe, a drainage pipe, and a water level gauge, the undisturbed soil containing cylinder Located above the leakage filter chamber, one end of the guide pipe is connected to the outlet of the leakage filter chamber, the other end of the guide pipe is located inside the water tank, the sampling pipe and the The lower ends of the drainage pipes are all inserted into the water tank, and the water level gauge is installed in the water tank. The invention is reasonable in design and simple in structure, and can be used for comprehensive quantitative determination of seepage process, nutrient and pesticide leaching in farmland soil, etc., to carry out control tests of water, fertilizer and pesticide coupling management measures, and to optimize the allocation of farmland raw source elements and reduce pesticides. Residue, leaching migration and crop absorption provide data support and provide research means for assessing the risk of water and soil environmental pollution.

Description

Farmland soil seepage water in-situ monitoring sampling device

technical field

The invention relates to the field of agriculture, in particular to an in-situ monitoring and sampling device for farmland soil seepage water.

Background technique

The large-scale application of chemical fertilizers, pesticides and livestock manure in farmland may lead to non-point source pollution, which poses a serious threat to the regional ecological environment and human health. It may not only pollute drinking water sources, but may also cause surface water eutrophication and groundwater pollution. .

Agricultural non-point source pollution has the characteristics of large randomness in the formation process, complex influencing factors, wide distribution, far-reaching impact, ambiguous mechanism, long incubation period, delayed occurrence, great harm, and high difficulty in management and control. Every year, huge losses are caused by agricultural non-point source pollution and pesticide pollution accidents, which have a serious negative impact on the sustainable development of my country's agricultural economy.

Therefore, in-situ measurement of farmland soil leakage process, research on farmland water, fertilizer, and pesticide migration behaviors are used to assess pollution risks, and provide reliable data and scientific basis for proposing agricultural non-point source pollution control and management measures. Significance.

In the prior art, the commonly used research methods of farmland soil seepage process mainly include the following three types:

1) The indoor leaching experiment of the undisturbed or filled soil column is used to explore the migration characteristics of nutrients and pesticides under the simulated rainfall, soil and moisture boundary conditions controlled indoors; the disadvantage of this method is that it cannot simulate the real field changes The depth and area of the soil column that can be simulated are also small due to hydrothermal conditions and hydrological conditions, and it is not suitable for soils with strong mechanization.

2) In the field, install soil tanks, build runoff plots, or build a soil seepage system (with a basement for monitoring and sampling) in the field, and measure the nutrients in different runoff types on the surface and underground under simulated rainfall or natural rainfall conditions and pesticide migration rules and influencing factors; the disadvantages of this method are that the construction cost is high, the damage area is large during installation, a long period of stable settlement is required, and once it is completed, it usually cannot be moved to another place for use.

3) The commercial lysimeter (weighable) needs to be equipped with an underground monitoring and sampling room; the system is very expensive and requires high technical requirements for maintenance.

To sum up, there is a need in this field for an in-situ monitoring and sampling system for farmland soil seepage water that is reasonably designed, simple, low-cost, and easy to implement. important meaning.

Contents of the invention

The purpose of the present invention is to provide an in-situ monitoring sampling device for farmland soil seepage water which is reasonable in design, simple and convenient, low in cost and easy to realize.

The invention provides an in-situ monitoring and sampling device for farmland soil leakage water, comprising: an undisturbed soil holding cylinder, a leakage filter chamber, a diversion pipe, a water tank, a sampling pipe, a drainage pipe and a water level gauge, the undisturbed soil The containing cylinder is located above the leakage filter chamber, one end of the guide pipe is connected to the outlet of the leakage filter chamber, the other end of the guide pipe is located inside the water tank, and the sampling Both the pipe and the lower end of the drainage pipe are inserted into the water tank, and the water level gauge is installed in the water tank.

Preferably, the sampling device for in-situ monitoring of farmland soil seepage water further includes a base, and the seepage filter chamber is arranged on the base.

Preferably, the seepage filter chamber includes a circumferential casing and a top plate, the top plate is connected to the bottom opening of the circumferential casing, and the bottom of the seepage filter chamber is inclined relative to the horizontal plane.

Preferably, a plurality of permeable holes are opened on the top plate.

Preferably, a drainage pipe is installed in the leakage filter chamber, and the drainage pipe includes a first water pipe and a second water pipe, the first water pipe and the second water pipe are connected in a T-shape, and the first water pipe Both the second water pipe and the second water pipe are provided with water inlet holes, and the end of the second water pipe far away from the first water pipe protrudes from the leaking filter chamber and is connected to the one end of the draft pipe.

Preferably, the water tank includes a box body, a hollow upper casing and a sampling pool, the lower end of the upper casing is connected to the upper surface of the box, and the interior of the upper casing communicates with the box , the sampling pool is installed on the inner wall of the upper casing, the lower end of the sampling pipe is inserted into the sampling pool, and the water level gauge is installed in the upper casing.

Preferably, the other end of the draft tube is located at the upper opening of the sampling pool.

Preferably, the water level gauge includes a float and a vertically arranged indicating rod, the lower end of the indicating rod is connected to the float, and a water level scale is formed on the inner wall of the upper casing.

Preferably, the drain pipe is installed in the upper casing, and the knife-type nozzle at the lower end of the drain pipe is inserted into the inside of the box.

Preferably, the sampling device for in-situ monitoring of farmland soil seepage water further includes a hand-held sampling pump, which is detachably connected to the upper port of the sampling pipe or the drainage pipe.

The advantage of the present invention compared with prior art is:

(1) The present invention is low in construction cost, compact in structure, easy to install, and has less damage to the experimental field, and can be used for field water, fertilizer, and drug control test research requiring multiple treatments. Other monitoring or sampling equipment (such as TDR or FDR moisture content probes, water potential meters, soil solution samplers, etc.) are inserted into the vertical or side openings of the box for in-situ comprehensive determination of various physical and chemical indicators.

(2) The present invention prevents the entry of underground soil moisture through the overall sealing and anti-seepage of the system, and can establish a hydrologically independent and clear water source leakage water monitoring system in the original soil column of the farmland in the field, and can implement dynamic sampling of leakage water samples, Combined with the analysis results of pollutant concentration, the migration flux and dynamic changes of nutrients and pesticides at the plot scale with underground runoff can be calculated.

(3) The device of the present invention can be disassembled and thus can be easily reused.

Description of drawings

Fig. 1 is the overall structure schematic diagram of the present invention;

Fig. 2 is the front view of cylinder cover;

Figure 3 is a top view of the cylinder cover;

Fig. 4 is the front view of cylinder;

Figure 5 is a top view of the cylinder;

Figure 6 is a perspective view of a seepage filter chamber;

Fig. 7 is the top view of seepage filter chamber;

Fig. 8 is a schematic diagram of the internal structure of the seepage filter chamber;

Figure 9 is a perspective view of the base;

Figure 10 is a top view of the base;

Figure 11 is a bottom view of the base;

Figure 12 is a perspective view of a water tank;

Figure 13 is a top view of the water tank;

Figure 14 is a schematic diagram of an embodiment of a draft tube;

Fig. 15 is a schematic diagram of the connection structure of an embodiment of the present invention.

Reference signs in the figure: 1, the undisturbed soil holding cylinder; 2, the seepage filter chamber; 3, the diversion pipe; 4, the water tank; 5, the sampling pipe; 6, the drainage pipe; 7, the water level gauge; 8, the cylinder Cover; 9. Drainage pipe; 10. Sampling tank; 11. Box body; 12. Base; 13. Peripheral shell; 14. Top plate; 15. Permeable hole; 16. First water pipe; 17. Second water pipe; 18 , upper shell; 19, float; 20, indicating rod; 21, cylinder wall; 22, reinforced U-shaped stainless steel groove; 23, connecting plate; , reinforcement plate; 28, bottom plate; 29, stainless steel pipe; 30, stainless steel threaded hose; 31, porous reinforcement plate; 32, upper stainless steel connecting plate; 33, waterproof sealant; 34, silicone sealing gasket; 35, lower stainless steel Connecting plate; 36, stainless steel bolts.

detailed description

Aiming at the shortage of practical equipment required for the research on the leakage of farmland soil water, fertilizer and medicine, the present invention provides an in-situ monitoring and sampling device for farmland soil leakage water, which is used to directly monitor the dynamics of farmland leakage water in situ. Study the migration law and influencing factors of water, fertilizer, medicine, etc. at the soil-water-crop interface.

As shown in Figures 1 to 15, the present invention provides an in-situ monitoring and sampling device for farmland soil leakage water, including: an original soil column leakage square box and a self-recording flow water tank, wherein the original soil column leakage square box includes stainless steel Square cylinder body 1 (i.e. the undisturbed soil holding cylinder), seepage water filter gravel bin 2 (i.e. seepage filter bin), and base 12; self-recording flow water tank includes water tank 4, sampling pool (10), sampling Pipe 5, drain pipe 6 and water gauge 7.

The stainless steel square cylinder body 1 is located above the seepage water filtering gravel bin 2, and one end of the diversion pipe 3 is connected with the water outlet of the T-shaped stainless steel drainage pipe (9) in the leaking water filtering sand gravel bin 2, and the diversion The other end of pipe 3 links to each other with the water inlet of the stainless steel drainage elbow of water tank 4. The lower end of the sampling tube 5 is inserted into the sampling pool 10 in the water tank 4 and contacts with its inner bottom surface. The lower end of the drainpipe 6 is inserted into the water tank 4 casing 11 and contacts with its inner bottom surface, and the water level gauge 7 is installed in the water tank 4 .

Please refer to Fig. 2 and Fig. 3, a plurality of reinforced U-shaped stainless steel grooves 22 can be installed on the upper surface of the cap 8 in the present invention to prevent the cap 8 from deforming and arching.

Please refer to Fig. 4 and Fig. 5, cylinder body 1 among the present invention comprises cylinder wall 21 and strengthened U-shaped stainless steel tank 22, wherein, the upper and lower ends of cylinder wall 21 are welded with connecting plate 23 protruding outwards, so as to be connected with cylinder Cover 8 is connected with seepage water filtering gravel storehouse 2. A plurality of reinforced U-shaped stainless steel grooves 22 are also arranged on the outer wall of the cylinder wall 21 along the circumference. The reinforced U-shaped stainless steel grooves 22 can prevent the ring cutter from lateral deformation and are used for fixing the cables during the ring cutter hoisting and overturning process.

Please refer to Fig. 6, Fig. 7 and Fig. 8, the seepage water filtering gravel silo 2 in the present invention comprises a circumferential shell 13 and a top plate 14, and a plurality of permeable holes 15 are opened on the top plate, and the connection between the top plate and the circumferential shell The top opening is welded, the cross section of the seepage water filter sand gravel bin 2 is trapezoidal, the upper bottom is 10cm, and the lower bottom is 15cm right-angled trapezoid. Reinforcing plate 24 is used for reinforcing and supporting, and a connecting plate 23 protruding outwards is welded at the lower end of leaking water filtering gravel bin 2 so as to be connected with base 12 .

Please refer to Fig. 9, Fig. 10 and Fig. 11, the section of base 12 is trapezoidal, and the upper bottom is 15cm, and the lower bottom is a right-angled trapezoid of 10cm, to ensure that the bottom is level after being connected with the seepage water filter gravel bin. The base 7 includes a base peripheral wall 25 on which a top plate 26 is mounted. Inside the peripheral wall 25 of the base, a plurality of reinforcement plates 27 are arranged in parallel, and a bottom plate 28 is arranged on the side of the lower opening of the peripheral wall 24 of the base for reinforcement and support.

Please refer to Fig. 1, the production and installation process of the present invention is as follows:

1) According to the inner diameter of the cylinder 1, take the original soil column in the test field, insert the cylinder 1 from above, install the cylinder cover 8, cut off the soil column at 20 cm below the bottom of the cylinder 1, turn over and take out the cylinder 1 , place it upside down on nearby flat ground. As shown in Figures 2 and 3, a plurality of reinforced U-shaped stainless steel grooves 22 may be installed on the upper surface of the cylinder cover 8 to prevent deformation and arching of the cylinder cover 8. For example, four reinforced U-shaped stainless steel grooves 22 can be installed, and these four reinforced U-shaped stainless steel grooves 22 can be arranged in a "feng" shape.

2) Flatten the bottom of the undisturbed soil column so that it is flush with the bottom of cylinder body 1, lay nylon nets, install the seepage water filter gravel bin 2, and then filter the seepage water in the seepage filter bin 2 in the order of fine sand, coarse sand, and pebbles. 2. Fill the anti-filter layer in the interior, and wrap the T-shaped stainless steel drainage tube 9 with nylon mesh at last.

3) Connect the connecting plate 23 at the bottom of the leaking water filter sand and gravel bin 2 with the top plate 26 of the base 12, turn over the entire leaking square box, remove the cylinder cover 8, and add water to the leaking square box from above to check its waterproof seal repair and repair any leaks that may be found.

4) Delineate the installation positions of the leakage square box and the self-recording flow water tank in the test field, pour the concrete platform base, then place the leakage square box and the self-recording flow water tank at the corresponding positions on the platform, and connect them with the diversion pipe 3 Both, water in the leaking square box again to check whether the diversion of the whole device is smooth and whether there is water leakage. If water leakage is found, it must be sealed and repaired in time.

5) Use solid bricks to build retaining walls (concrete platform at the bottom) on both sides and the upper part of the diversion pipe 3, so as to avoid the pressure loss of the surrounding soil gravity pressure to the diversion pipe 3 when backfilling the square box.

6) When backfilling the soil, backfill the excavated soil layer by layer according to the soil development level, until the entire excavation part is completely filled, and pay attention to the top surface of the leaking square box being flush with the original ground level soil of the test field. The in-situ monitoring and sampling system for water leakage has been constructed and is ready for use.

When in use, the water flows downward from the cylinder body 1 into the seepage filter chamber 2, and after being filtered through the top plate 14 of the seepage filter chamber 2 and the reverse filter layer in turn, the leaked water is collected through the T-shaped stainless steel drainage pipe 9, and the leaking water is collected by the guide Flow tube 3 flows into tank 4 . When sampling is required, the hand-held sampling pump can be detachably connected to the water outlet on the top of the water tank 4, the drain pipe valve is closed, and the sampling pipe valve is opened to extract the water entering the water tank sampling pool 10. In this way, in-situ continuous monitoring and sampling of soil seepage water can be realized, which can fully reflect the dynamic change law of farmland soil seepage water flux, and the total seepage can be estimated based on the measurement of the water level in the water tank and the displacement.

Due to the adoption of the above-mentioned technical scheme, the present invention has reasonable design and simple structure, and can be used for comprehensive quantitative determination of seepage process, nutrient and pesticide leaching in farmland soil, etc., to carry out control tests of water, fertilizer and pesticide coupling management measures, and provide a source of farmland growth. The optimal allocation of elements, reduction of pesticide residues, leaching migration and crop absorption provide data support, and provide research means for assessing the risk of water and soil environmental pollution.

As shown in Figures 1 to 11, the connection plate between the stainless steel square cylinder body 1 and the cylinder cover 8 and the seepage water filter sand and gravel bin 2, and the connection plate between the seepage water filter sand and gravel bin 2 and the base 12 are provided with multiple bolt holes , the hole diameter is 1.2cm, and the hole spacing is 10.4cm.

As shown in Fig. 6 and Fig. 7, the seepage water filtering gravel bin 2 includes a circumferential shell 13 and a top plate 14, and a plurality of permeable holes 15 are opened on the top plate 14, and the aperture diameter of the permeable holes 15 is 0.8 cm, and the hole spacing is 2 cm. . The top plate 14 is welded to the top opening of the circumferential casing 13, and the bottom of the seepage water filter gravel bin 2 is inclined relative to the horizontal plane. The cross-section of the circumferential shell 13 is a right-angled trapezoid, which can collect the leaking water of the entire soil column in an artesian state.

As shown in Figure 8, a porous T-shaped stainless steel drainage pipe is welded on the reinforcing plate 24 of the bottom opening of the seepage water filter gravel bin 2, which is used for the export of the seepage water (bottom view). The lower end of the leaking water filter gravel storehouse 2 protrudes outwards and is welded with a 4cm long connecting plate 23 for drilling and connecting with the top plate 26 of the base 12 using stainless steel bolts. The seepage water is filtered and the gravel bin 2 is filled with a reverse filter layer to prevent sediment from entering the seepage water confluence sampling system.

In a more preferred embodiment, please refer to FIG. 8, the T-shaped stainless steel drainage pipe 9 is welded by the first water pipe 16 and the second water pipe 17, and the first water pipe 16 and the second water pipe 17 are provided with water inlets. Hole, one end (water outlet) of the second water pipe 17 away from the first water pipe 16 is located at the outer side of the circumferential housing 13 of the seepage water filter gravel bin 2, and is connected with the guide pipe. In the embodiment of the guide tube 3 shown in Figure 14, a stainless steel pipe 29 is used to connect two stainless steel threaded hoses 30 (drain tubes) between the leakage square box and the self-recording flow water tank, so as to To avoid the influence of the uneven settlement of the soil in the long-term test on the system, which may cause the distortion and bending damage of the diversion pipe, the side of the self-recording flow water tank of the diversion pipe is slightly lower, so that the leakage water enters the water tank in a self-flowing state.

Please refer to Fig. 12 and Fig. 13, preferably, the water tank 4 in the present invention includes a box body 11, a hollow upper casing 18 and a sampling pool 10, the lower end of the upper casing 18 is connected with the upper surface of the box body 11, and the upper The inside of the casing 18 communicates with the casing 11, the sampling tank 10 is installed on the inner wall of the upper casing 18, the lower end of the sampling tube 5 is inserted into the sampling tank 10, and the water level gauge 7 is installed in the upper casing 18. Preferably, the water outlet of the stainless steel drainage elbow of the water tank 4 connected to the draft pipe 3 is inserted into the sampling pool 10 . After the water flows out from the draft pipe 3, it first flows into the sampling tank 10. When the sampling tank 10 is filled, the water sample overflows from the sampling tank 10 and flows downward into the lower casing 11. Preferably, the in-situ monitoring and sampling device for farmland soil seepage water further includes a drain pipe 6 installed in the upper casing 18 , and the lower end of the drain pipe 6 is inserted into the box body 11 . Like this, when water level gauge 7 detects that water level reaches predetermined height, test personnel can utilize the pumping devices such as water pump to discharge the water in casing 11 by the upper end water outlet of drainpipe 6. Preferably, the length of the box body 11 is 0.6m, the width is 0.6m, and the height is 0.4m; the length and width of the upper casing 15 are both 0.1m. The water tank 4 is sealed and anti-seepage as a whole, and the top is welded with a stainless steel rain-proof flip cover. In the upper casing 18, 1 cm away from its bottom, on its inner side wall, a sampling pool 10 with a length and width of 5 cm and a height of 7 cm is welded. The diameter of the sampling pipe 5 may be 1 cm; the diameter of the drain pipe 6 may be 2.5 cm. The bottoms of the sampling pipe 5 and the drain pipe 6 are knife-shaped nozzles, which contact the inner bottom surface of the sampling pool 10 and the inner bottom surface of the box body 11 respectively. The maximum water height of the upper shell tube 18 above the ground surface is at least more than 30cm (avoiding field water from flowing into the water tank), so as to determine the total length of the upper shell tube 18.

In the embodiment shown in FIG. 11 , preferably, the water level gauge 7 includes a float 19 and a vertically arranged indicating rod 20 , the lower end of the indicating rod 20 is connected to the float 19 , and a water level scale is formed on the inner wall of the upper casing 18 . In this way, when the indicating rod 20 (such as a steel wire rope, etc.) moves upward under the action of the float 19, the current water level can be reflected on the water level scale. Thus, the tester can observe the current water level at the upper opening of the upper casing 18 to determine whether it is necessary to drain water through the drain pipe 6 .

In another unillustrated embodiment, the water level gauge in the present invention can also adopt an electronic method (such as a pressure type or a capacitive type), and when it detects that the water level reaches a predetermined height value, it will be sent to the test personnel through a wireless transmission module. A piece of information, for example, can be a short message, or it can be an application push message of other mobile APPs, etc., to help the test personnel perform sampling and drainage treatment in a timely manner.

As shown in FIG. 12 , a plurality of parallel perforated reinforcing plates 31 are arranged inside the box body 11 to prevent the upper part of the box body 11 from being damaged under pressure after being filled with soil.

Please refer to FIG. 15 , the connection between the cylinder body 1 and the seepage water filtering gravel bin 2 , and between the seepage water filtering sand gravel bin 2 and the base 12 is realized through the connection structure shown in FIG. 15 . As shown in Figure 15, the joints between the parts of the leaking square box are stainless steel plate 32 (ie each connecting plate), waterproof sealant 33, silicone gasket 34, waterproof sealant 33, stainless steel plate from top to bottom. The plates 35 (that is, the connecting plates) are integrally fixed with stainless steel bolts 36 to achieve the overall sealing and anti-seepage effect of the leaching meter, and avoid the influence of underground external moisture on the measurement of leakage water flux and sample collection.

Preferably, the leaking square box and the self-recording flow water tank in the present invention all use stainless steel plates, aiming at different soil types (acid, alkaline, neutral) and groundwater conditions (perennial flooding, drought, semi-arid, etc.) Coatings with different functions (wear-resistant coatings, chemical corrosion-resistant coatings, anti-oxidation coatings, etc.) can be used on the surface of stainless steel plates.

The invention has the advantages of simple installation, low construction cost, small damage area of excavation and backfilling, and the monitoring and sampling analysis of farmland soil seepage water can be carried out immediately after installation. In addition, the system can be disassembled for easy installation and use.

Claims (10)

1. An in-situ monitoring and sampling device for farmland soil leakage water, characterized in that it comprises: an undisturbed soil holding cylinder (1), a leakage filter chamber (2), a diversion pipe (3), and a water tank (4) , a sampling pipe (5), a drainpipe (6) and a water level gauge (7), the undisturbed soil holding cylinder (1) is located above the seepage filter bin (2), and the draft pipe (3 ) is connected to the outlet of the leakage filter chamber (2), the other end of the guide pipe (3) is located inside the water tank (4), the sampling pipe (5) and the drain pipe The lower ends of (6) are all inserted in the water tank (4), and the water level gauge (7) is installed in the water tank (4). 2. The in-situ monitoring and sampling device for farmland soil leakage water according to claim 1, wherein the in-situ monitoring and sampling device for farmland soil leakage water also includes a base (12), and the leakage filter bin ( 2) Set on the base (12). 3. The in-situ monitoring sampling device for farmland soil leakage water according to claim 1, characterized in that, the leakage filter bin (2) comprises a circumferential shell (13) and a top plate (14), and the top plate (14) is connected to the bottom opening of the circumferential casing (13), and the bottom of the seepage filter chamber (2) is arranged obliquely relative to the horizontal plane. 4. The sampling device for in-situ monitoring of farmland soil leakage water according to claim 3, characterized in that a plurality of permeable holes (15) are opened on the top plate (14). 5. according to claim 1 and 2 described in-situ monitoring and sampling devices for farmland soil seepage water, it is characterized in that a drainage pipe is installed in the leakage filter bin (2), and the drainage pipe includes a first water pipe ( 16) and the second water pipe (17), the first water pipe (16) and the second water pipe (17) are connected in a T-shape, and both the first water pipe (16) and the second water pipe (17) A water inlet hole is provided, and the end of the second water pipe (17) away from the first water pipe (16) stretches out from the leakage filter chamber (2) and connects with the end of the draft pipe (3). connect. 6. The in-situ monitoring and sampling device for farmland soil leakage water according to claim 1, wherein the water tank (4) comprises a casing (11), a hollow upper casing (18) and a sampling pool (10 ), the lower end of the upper shell (18) is connected to the upper surface of the box (11), and the inside of the upper shell (18) communicates with the box (11), the sampling pool (10) installed on the inner wall of the upper casing (18), the lower end of the sampling pipe (5) is inserted into the sampling pool (10), and the water level gauge (7) is installed on the upper casing (18). 7. The sampling device for in-situ monitoring of farmland soil leakage water according to claim 6, characterized in that, the other end of the draft pipe (3) is located at the upper opening of the sampling pool (10). 8. The in-situ monitoring sampling device for farmland soil leakage water according to claim 6, characterized in that, the water level gauge (7) includes a float (19) and a vertically arranged indicating rod (20), and the indicating The lower end of the rod (20) is connected with the float (19), and a water level scale is formed on the inner wall of the upper casing (18). 9. The in-situ monitoring sampling device for farmland soil leakage water according to claim 6, characterized in that, the drain pipe (6) is installed in the upper casing (18), and the drain pipe (6) ) at the lower end of the knife nozzle is inserted into the box (11) inside. 10. The in-situ monitoring and sampling device for farmland soil leakage water according to claim 1, characterized in that the in-situ monitoring and sampling device for farmland soil leakage water also includes a hand-held sampling pump, which is connected with the sampling pipe (5) or drainage The upper end port of the tube (6) is detachably connected.