An experimental device for farmland water research

Abstract

This utility model discloses an experimental device for farmland water research, relating to the field of farmland groundwater research technology. It includes at least one soil column tube; the soil column tube is placed vertically, and a separating membrane is installed inside the soil column tube; the separating membrane divides the inner cavity of the soil column tube into a soil cavity and a seepage cavity; the separating membrane allows water to communicate between the soil cavity and the seepage cavity, and restricts soil permeation within the soil cavity; the sidewall of the soil column tube corresponding to the seepage cavity is a transparent sidewall, through which the water level within the seepage cavity can be seen; graduation lines are provided on the transparent sidewall; multiple soil solution samplers are fixedly installed on the sidewall of the soil column tube along its axial direction, with the sampling port of each soil solution sampler located within the soil cavity at a corresponding height. It enables experimental research on farmland water levels and the infiltration patterns of groundwater leachate.

Description

Technical Field

[0001] This utility model relates to the field of farmland groundwater research technology, and in particular to an experimental device for farmland water research. Background Technology

[0002] Currently, the uneven distribution of arable land and water resources in irrigation areas, coupled with long-term unreasonable irrigation methods, has led to rising groundwater levels, increased mineralization, and exacerbated soil salinization, severely restricting the development of the corn industry in these areas. Therefore, developing water-saving irrigation, improving agricultural water resource utilization efficiency, alleviating the supply and demand imbalance of arable land resources, and reducing the degree and area of ​​soil salinization are of great significance to the sustainable development of industries in irrigation areas.

[0003] During the rice growing season, the groundwater (shallow groundwater) in paddy fields is very shallow, generally less than 1.0m. When it rains or irrigates, the groundwater level rises rapidly to the surface and forms a water layer. When the water on the field surface is too deep and cannot be drained in time, waterlogging will occur. Even if the water layer on the field surface is within a suitable range, due to the backwater effect from the surrounding water level and the lack of seepage in the field, toxic substances (such as methane and hydrogen sulfide) will accumulate in the rice roots under the action of anaerobic microorganisms, causing waterlogging damage to the rice. As the water in the field is continuously consumed, the water layer on the field surface recedes, the groundwater level gradually drops, and the moisture content of the root layer soil also decreases. When the groundwater level drops to a certain depth, the supply of rising capillary water to the root layer soil is significantly reduced, and the moisture in the root layer soil cannot meet the water absorption needs of the crop roots. At this time, the rice growth suffers from drought due to water stress.

[0004] Therefore, by studying the water level and groundwater solution in farmland, we can accurately understand the soil moisture status and provide guidance for rational irrigation, prevention of soil salinization, and control of pests and diseases. Based on this, it is necessary to provide an experimental device for farmland water research. Utility Model Content

[0005] The purpose of this invention is to provide an experimental device for farmland water research, in order to solve the problems existing in the prior art, and to realize experimental research on farmland water level and the infiltration law of groundwater leachate.

[0006] To achieve the above objectives, this utility model provides the following solution:

[0007] This invention provides an experimental apparatus for farmland water research, comprising at least one soil column tube; the soil column tube is placed vertically, and a separating membrane is provided inside the soil column tube; the separating membrane divides the inner cavity of the soil column tube into a soil cavity and a seepage cavity; the separating membrane allows water to communicate between the soil cavity and the seepage cavity, and the separating membrane restricts soil permeation within the soil cavity; the side wall of the soil column tube corresponding to the seepage cavity is a transparent side wall, through which the water level in the seepage cavity can be seen; graduation lines are provided on the transparent side wall; multiple soil solution samplers are fixedly arranged on the side wall of the soil column tube along the axial direction of the soil column tube, and the sampling port of each soil solution sampler is located in the soil cavity at a corresponding height.

[0008] Preferably, the lower end of the soil column pipe is provided with a drain outlet, which is connected to the lower openings of both the soil cavity and the seepage cavity; and a valve is provided at the drain outlet.

[0009] Preferably, the lower opening of the soil column pipe is connected to the drain outlet through a filter.

[0010] Preferably, the soil column tube is a transparent tube.

[0011] Preferably, the filter includes a metal filter screen, which is disposed at the lower end opening of the soil column pipe.

[0012] Preferably, the filter further includes a first gauze, which is located at the upper end of the metal filter screen.

[0013] Preferably, the filter further includes a second gauze, which is located at the lower end of the metal filter screen.

[0014] Preferably, a sealing plug is provided at the lower end opening of the soil column pipe, and the sealing plug is provided with the drainage port.

[0015] Preferably, the upper opening of the soil column pipe is also provided with a detachable top cover.

[0016] Preferably, there are two soil column pipes, and both soil column pipes are fixedly mounted on a fixed base frame.

[0017] The present invention achieves the following technical advantages over the prior art:

[0018] This invention provides an experimental apparatus for farmland water research. It involves placing farmland soil and a plant, such as a rice stalk, inside a soil cavity, allowing the entire apparatus to receive natural sunlight. Water is slowly injected into the soil, and the water in the soil passes through a separating membrane into the infiltration cavity. The transparent sidewalls facilitate direct observation of water level changes within the infiltration cavity. A scale is used to quantify the water level height, and combined with time recording, the water infiltration rate is calculated. Soil solution samplers at different heights can collect soil leachate from different depths. By analyzing the composition of the sampled solution and combining it with water level data, the migration patterns of water infiltration are revealed. Furthermore, the scale readings of the water level can assist in verifying water level gauges used in farmland. By placing the water level gauge inside the infiltration cavity and comparing the reading with the values ​​read on the scale, the water level gauge used in farmland can be calibrated. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 A schematic diagram of the overall structure of the experimental apparatus for farmland water research provided by this utility model;

[0021] Figure 2 A front view of the experimental apparatus for farmland water research provided by this utility model;

[0022] Figure 3 Top view of the experimental apparatus for farmland water research provided by this utility model;

[0023] Figure 4 A front view of a single soil column tube in the experimental apparatus for farmland water research provided by this utility model;

[0024] Figure 5 A schematic diagram of the internal structure of a single soil column tube in the experimental apparatus for farmland water research provided by this utility model;

[0025] Figure 6 A top view of a single soil column tube in the experimental apparatus for farmland water research provided by this utility model.

[0026] In the picture:

[0027] 10-Soil column tube; 11-Separation membrane; 12-Soil cavity; 13-Infiltration cavity; 14-Soil solution sampler; 15-Sealing stopcock;

[0028] 20 - Fixed base frame. Detailed Implementation

[0029] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0030] The purpose of this invention is to provide an experimental device for farmland water research, in order to solve the problems existing in the prior art, and to realize experimental research on farmland water level and the infiltration law of groundwater leachate.

[0031] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0032] Example 1

[0033] This embodiment provides an experimental apparatus for farmland water research, such as... Figures 1-6 As shown, it includes at least one soil column tube 10; the soil column tube 10 is placed vertically, and a separator 11 is provided inside the soil column tube 10; the separator 11 divides the inner cavity of the soil column tube 10 into a soil cavity 12 and a seepage cavity 13; the separator 11 allows water to communicate between the soil cavity 12 and the seepage cavity 13, and the separator 11 restricts soil permeation within the soil cavity 12; the side wall of the soil column tube 10 corresponding to the seepage cavity 13 is a transparent side wall, through which the water level in the seepage cavity 13 can be seen; a scale line is provided on the transparent side wall; multiple soil solution samplers 14 are fixedly arranged on the side wall of the soil column tube 10 along the axial direction of the soil column tube 10, and the sampling port of each soil solution sampler 14 is located in the soil cavity 12 at the corresponding height.

[0034] By placing farmland soil and a plant, such as rice, inside the soil cavity 12 and exposing the entire structure to natural sunlight, water is slowly injected into the soil. The water in the soil enters the infiltration cavity 13 through the separating membrane 11. The transparent sidewalls facilitate direct observation of water level changes within the infiltration cavity 13. Scale lines are used to quantify water level height, and combined with time recording, the water infiltration rate is calculated. Soil solution samplers 14 at different heights can collect soil leachate at different depths. By analyzing the composition of the sampled solution and combining it with water level data, the migration pattern of water infiltration is revealed. Furthermore, the scale lines for reading the water level can also assist in verifying water level gauges used on farmland. By placing the water level gauge inside the infiltration cavity 13 and comparing the reading with the values ​​read on the scale lines, the water level gauges used on farmland can be verified.

[0035] The overall structural composition of the experimental apparatus for farmland water research in this embodiment is as follows:

[0036] Among the optional solutions in this embodiment, the more preferred one is as follows: Figure 1 As shown, there are two soil column tubes 10, and both soil column tubes 10 are fixedly mounted on a fixed base frame 20. By setting two soil column tubes 10, one can be used alone for experimental research related to water level, while the other can be used alone for experimental research related to the seepage law of leachate.

[0037] The following are the relevant settings for a single soil column pipe 10:

[0038] In the optional embodiments of this example, a more preferred option is that the upper opening of the soil column 10 is also provided with a detachable top cover. The top cover should be closed normally to prevent rainwater from entering during rainy weather, but can be opened when sampling is required.

[0039] Among the optional solutions in this embodiment, the more preferred one is as follows: Figure 2 and Figure 4 As shown, the lower end of the soil column pipe 10 is provided with a drain outlet, which is connected to the lower openings of the soil cavity 12 and the seepage cavity 13; and a valve is provided at the drain outlet.

[0040] In the optional schemes of this embodiment, the soil column pipe 10 is preferably a transparent pipe.

[0041] Among the optional solutions in this embodiment, the more preferred one is as follows: Figure 1 , Figure 2 and Figure 4 As shown, a sealing plug 15 is provided at the lower opening of the soil column pipe 10, and a drain port is provided on the sealing plug 15.

[0042] The following are the instructions regarding the filter settings at the bottom of the soil column pipe 10:

[0043] In the optional solutions of this embodiment, it is more preferred that the lower opening of the soil column pipe 10 is connected to the drain outlet through a filter.

[0044] In the optional embodiments of this example, the filter includes a metal filter screen, which is disposed at the lower end opening of the soil column pipe 10.

[0045] In the optional embodiments of this example, more preferably, the filter further includes a first gauze, which is located at the upper end of the metal filter screen.

[0046] In an optional embodiment, more preferably, the filter further includes a second gauze, which is located at the lower end of the metal filter screen.

[0047] Regarding other settings:

[0048] Specifically, the soil column 10 is a circular tube into which a 1m deep soil sample taken from the field is inserted. Dutch Rhizon series soil solution samplers 14 are installed every 10cm vertically along the sidewalls of the soil column, with the connections sealed beforehand to prevent leachate leakage. The soil is cultivated like normal field crops, with rice planted on top, and the fertilization rate and agricultural practices are consistent with local practices. Samples are taken on days 1, 3, 5, and 7 after each fertilization, sequentially from top to bottom. The collected samples are promptly filtered through a 0.45µm filter membrane into centrifuge tubes and stored at -20℃. They are then sent to the laboratory for testing of total nitrogen, soluble total nitrogen, nitrate nitrogen, ammonia nitrogen, total phosphorus, and orthophosphate. By comparing the concentration differences of various indicators of the leachate in each soil layer, the infiltration pattern of the leachate in agricultural production can be understood.

[0049] This utility model uses specific examples to illustrate its principles and implementation methods. The above description of the embodiments is only for the purpose of helping to understand the method and core idea of ​​this utility model. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the idea of ​​this utility model. In summary, the content of this specification should not be construed as a limitation of this utility model.

Claims

1. An experimental apparatus for farmland water research, characterized in that: Includes at least one soil column tube; The soil column is placed vertically, and a separator membrane is installed inside the soil column. The separator membrane divides the inner cavity of the soil column into a soil cavity and a seepage cavity. The separator membrane allows water to communicate between the soil cavity and the seepage cavity, and restricts soil permeation within the soil cavity. The sidewall of the soil column pipe corresponding to the seepage cavity is a transparent sidewall, through which the water level in the seepage cavity can be seen; the transparent sidewall is provided with scale lines. Multiple soil solution samplers are fixedly installed on the side wall of the soil column pipe along the axial direction of the soil column pipe, and the sampling port of each soil solution sampler is located in the soil cavity at the corresponding height.

2. The experimental apparatus for farmland water research according to claim 1, characterized in that: The lower end of the soil column pipe is provided with a drain outlet, which is connected to the lower openings of the soil cavity and the seepage cavity; and a valve is provided at the drain outlet.

3. The experimental apparatus for farmland water research according to claim 2, characterized in that: The lower opening of the soil column pipe is connected to the drainage port through a filter.

4. The experimental apparatus for farmland water research according to claim 1, characterized in that: The soil column tube is a transparent tube.

5. The experimental apparatus for farmland water research according to claim 3, characterized in that: The filter includes a metal filter screen, which is disposed at the lower end opening of the soil column pipe.

6. The experimental apparatus for farmland water research according to claim 5, characterized in that: The filter also includes a first gauze cloth located at the upper end of the metal filter screen.

7. The experimental apparatus for farmland water research according to claim 5, characterized in that: The filter also includes a second gauze, which is located at the lower end of the metal filter screen.

8. The experimental apparatus for farmland water research according to claim 2, characterized in that: A sealing plug is provided at the lower opening of the soil column pipe, and the drain port is provided on the sealing plug.

9. The experimental apparatus for farmland water research according to claim 1, characterized in that: The upper opening of the soil column pipe is also equipped with a removable top cover.

10. The experimental apparatus for farmland water research according to claim 1, characterized in that: The number of soil column pipes is two, and both soil column pipes are fixedly installed on a fixed base frame.

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