Device for researching corrosion reduction effect of vegetation in raindrop splash erosion

Abstract

The utility model discloses a device for studying the corrosion reduction effect of vegetation in raindrop splash erosion, which comprises a splash erosion test device and a water pressure control device, the splash erosion test device comprises a fixed frame, a water flow injection pipe arranged below the fixed frame and a sample cylinder arranged above the fixed frame, the water flow injection pipe is vertically arranged, and the water pressure control device is arranged above the sample cylinder. A nozzle is arranged at the top end of the water jet pipe, the sample cylinder is used for filling to-be-tested soil with vegetation, an opening of the sample cylinder faces downwards and is located over the nozzle, a water retaining mechanism used for blocking water flow is further arranged on the portion, between the nozzle and the sample cylinder, of the fixing frame, and the water retaining mechanism can intermittently prevent the water flow from impacting the to-be-tested soil. The water pressure control device comprises a pressure-resistant container and an air compressor, the bottom of the pressure-resistant container is communicated with a water inlet of the water flow injection pipe through a water pipe, and an air outlet of the air compressor is connected with an air inlet of the pressure-resistant container. The device can be used for researching the erosion resisting effect of vegetation in the raindrop splashing erosion effect.

Description

Technical Field

[0001] The utility model relates to the technical field of soil erosion physical model research, in particular to a device for studying the erosion reduction effect of vegetation in raindrop splash erosion. Background Art

[0002] Soil erosion leads to serious degradation of land and ecosystem functions and is one of the major global environmental problems. The external forces that cause soil erosion mainly include water, freeze-thaw, gravity and wind. In recent years, the fluctuations and extreme changes in climate factors have led to an increase in the intensity and degree of hydraulic erosion, which has received increasing attention in soil erosion research. As one of the main types of soil erosion, hydraulic erosion is driven by rainfall or surface runoff, destroying, eroding and transporting soil, causing thinning of the soil layer, soil degradation, and serious damage to the ecological balance. In hydraulic erosion, the phenomenon of soil structure destruction and soil particle displacement caused by the splashing action of raindrops is called raindrop splash erosion, also known as splash erosion, which is mainly affected by factors such as climate, soil and vegetation.

[0003] Vegetation cover is considered an effective measure to reduce splash erosion. However, the research on the effect of vegetation on splash erosion is still insufficient, and how to evaluate the erosion resistance of vegetation under raindrop splashing still needs further research. Therefore, quantifying the erosion resistance of vegetation under splash erosion and exploring the influence of vegetation roots and stems and leaves on the evolution of erosion morphology during splash erosion are urgent needs for soil erosion prevention and control in the context of ecological civilization construction.

[0004] Existing devices and methods for studying soil erosion fail to take into account the erosion resistance of vegetation during splash erosion, as well as the influence of vegetation roots and stems and leaves on the evolution of erosion morphology during splash erosion. Summary of the invention

[0005] The purpose of the utility model is to provide a device for studying the erosion reduction effect of vegetation in raindrop splash erosion, by controlling precipitation parameters such as raindrop splash pressure and flow rate, establishing the relationship between vegetation parameters and soil erosion morphological evolution, and studying the role of vegetation in resisting erosion in raindrop splash erosion.

[0006] In order to achieve the above-mentioned purpose, the utility model adopts the following technical scheme.

[0007] The invention discloses a device for studying the erosion reduction effect of vegetation in raindrop splash erosion, comprising a splash erosion test device and a water pressure control device.

[0008] The splash test device includes a fixed frame, a water jet pipe arranged below the fixed frame and a sample tube arranged above the fixed frame. The water jet pipe is arranged vertically, and a nozzle is arranged at the top of the water jet pipe. The sample tube is used to load the soil to be tested planted with vegetation. The opening of the sample tube is arranged downward and is located directly above the nozzle. A water retaining mechanism for shielding water flow is also arranged between the nozzle and the sample tube on the fixed frame. The water retaining mechanism can intermittently block the water flow from impacting the soil to be tested.

[0009] The water pressure control device includes a pressure-resistant container and an air compressor. The bottom of the pressure-resistant container is connected to the water inlet of the water jet pipe through a water pipe, and the air outlet of the air compressor is connected to the air inlet of the pressure-resistant container, which is used to generate pressure in the pressure-resistant container to make water jet out through the nozzle.

[0010] Furthermore, the water-blocking mechanism includes a rotating shaft rotatably arranged on a fixed frame and a baffle fixedly connected to the rotating shaft. The rotating shaft is arranged parallel to the water jetting pipe, and the baffle is perpendicular to the rotating shaft. Rotating the rotating shaft so that the baffle is located directly above the nozzle can block the water flow. Rotating the rotating shaft so that the baffle is moved away from directly above the nozzle can allow the water flow to continue to impact the soil to be tested in the sample tube.

[0011] Furthermore, a weight detection device is provided below the pressure-resistant container for detecting the amount of remaining water in the water tank.

[0012] Furthermore, a sample holder with adjustable position is provided on the fixing frame, and the sample tube is fixedly connected to the sample holder. The distance between the sample tube and the nozzle can be adjusted by adjusting the vertical height of the sample holder.

[0013] Furthermore, the rotating shaft is driven to rotate by a motor, and the water flow can be quickly cut off or restored by controlling the motor.

[0014] Furthermore, the weight detection device is an electronic scale.

[0015] Furthermore, the inner diameter of the nozzle orifice is 0.8 to 1.0 mm.

[0016] Furthermore, the device also includes a CT scanning device for real-time observation and recording of the development and evolution process of the tested soil under water erosion.

[0017] After adopting the above technical solution, the utility model has the following beneficial effects:

[0018] 1. The utility model has a simple structure and a small size, which is convenient for obtaining vegetation parameters and improving test accuracy;

[0019] 2. The utility model adopts an inverted soil sample tube design, which can quickly drain the water splashing the soil without affecting the splashing effect of subsequent raindrops;

[0020] 3. The utility model uses CT non-destructive scanning technology to achieve the quantification and visualization of the evolution process of erosion morphology, and can accurately depict the development process of soil erosion in time and space dimensions;

[0021] 4. Measurement of vegetation parameters. Considering the influence of vegetation stems, leaves and roots on splash erosion, quantifying vegetation stems, leaves and roots, and combining them with the above-mentioned erosion morphology evolution, the spatiotemporal relationship between vegetation parameters and erosion morphology can be established. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the overall structure of the utility model.

[0023] Description of the drawings: 1. Fixing frame, 11. Sample holder, 2. Water jet tube, 21. Nozzle, 3. Sample tube, 4. Water retaining mechanism, 41. Rotating shaft, 42. Baffle, 5. Pressure container, 51. Water pipe, 6. Air compressor, 7. Weight detection device, 8. Soil to be tested, 9. Vegetation. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical scheme and advantages of the utility model more clearly understood, the characteristics and performance of a device for studying the erosion reduction effect of vegetation in raindrop splash erosion in the utility model are further described in detail below in conjunction with the accompanying drawings and embodiments.

[0025] The invention discloses a device for studying the erosion reduction effect of vegetation in raindrop splash erosion, comprising a splash erosion test device and a water pressure control device.

[0026] The sputtering test device comprises a fixing frame 1 , a water jetting pipe 2 arranged below the fixing frame 1 , and a sample tube 3 arranged above the fixing frame 1 .

[0027] The water jet pipe 2 is vertically arranged, and a nozzle 21 is arranged at the top of the water jet pipe 2. The inner diameter of the nozzle 21 orifice should be such that the water jetted out simulates the form of natural precipitation as much as possible. Preferably, the inner diameter of the nozzle 21 orifice in this embodiment is 0.8-1.0 mm.

[0028] The sample tube 3 is used to fill the soil 8 to be tested with vegetation 9. The opening of the sample tube 3 is set downward and is located directly above the nozzle 21. The sample tube 3 is connected to the fixing frame 1 through the sample holder 11, and the sample holder 11 is adjustably fixed to the fixing frame 1. By adjusting the vertical height of the sample holder 11, the distance between the sample tube 3 and the nozzle 21 can be adjusted.

[0029] A water blocking mechanism 4 for blocking water flow is also provided on the fixing frame 1 between the nozzle 21 and the sample tube 3 . The water blocking mechanism 4 can intermittently block the water flow from impacting the soil to be tested 8 .

[0030] The water retaining mechanism 4 includes a rotating shaft 41 rotatably arranged on the fixing frame 1 and a baffle 42 fixedly connected to the rotating shaft 41. The rotating shaft 41 is arranged parallel to the water jetting pipe 2, and the rotating shaft 41 is driven to rotate by a motor, and the water flow can be quickly cut off or restored by controlling the motor, and the baffle 42 is perpendicular to the rotating shaft 41. Rotating the rotating shaft 41 so that the baffle 42 is located directly above the nozzle 21 can block the water flow, and rotating the rotating shaft 41 so that the baffle 42 is moved away from directly above the nozzle 21 can allow the water flow to continue to impact the soil to be tested 8 in the sample tube 3.

[0031] The water pressure control device includes a pressure-resistant container 5 and an air compressor 6 .

[0032] The bottom of the pressure-resistant container 5 is connected to the water inlet of the water jet pipe 2 through a water pipe 51. A weight detection device 7 is provided below the pressure-resistant container 5 to detect the amount of remaining water in the water tank. Preferably, the weight detection device 7 is an electronic scale.

[0033] The air outlet of the air compressor 6 is connected to the air inlet of the pressure-resistant container 5 , so as to generate pressure in the pressure-resistant container 5 so that the water flows out through the nozzle 21 .

[0034] The device also includes a CT scanning device for real-time observation and recording of the development and evolution of the tested soil 8 under water erosion.

[0035] In the specific implementation, the sample needs to be prepared before the test. When preparing the sample, the soil sample properties must first be measured, the soil 8 to be tested is selected, sieved and the basic physical properties of the soil 8 to be tested, such as soil particle density, optimum moisture content and maximum dry density, are measured.

[0036] After testing and recording the physical parameters of the soil 8 to be tested, the soil 8 to be tested is loaded. Before loading, the mass of each layer of soil sample is calculated according to a certain soil moisture content and compaction degree. The soil samples are loaded into the sample tube 3 in layers, wherein the top layer is the seeding layer, which is about 10 mm thick. The compaction degree of the seeding layer is slightly lower than that of the other three layers to promote plant growth. After each layer of soil sample is loaded, it is compacted to the designed height, and the connecting surface of each layer of soil sample is shaved.

[0037] After the soil to be tested 8 is filled in the sample tube 3, the experimental vegetation 9 is sown in the soil to be tested 8 and maintained. First, the type of vegetation 9 is selected, and the mass of the seeds to be sown is calculated according to a certain sowing amount, purity and germination rate. The seeds are sown in the sowing layer of the soil sample, and the sample tube 3 is placed outdoors for maintenance. A transparent canopy can be set above the sample tube 3 to prevent rainfall from eroding the sample. A temperature and humidity sensor is set near the sample to monitor the outdoor temperature and humidity. If the outdoor temperature is too low, it can be moved indoors for maintenance. Water the sample in a timely manner. A watering can can be used to replenish water in a quantitative manner each time.

[0038] After the seeds germinate and grow to a predetermined state, the parameters of the upper and lower parts of the vegetation are measured. The upper part of the vegetation parameter measurement mainly measures the number of germinations and the maximum grass length, where the number of germinations is the number of stems close to the soil interface. The lower part of the vegetation parameter measurement mainly measures the plant root system, and the root system parameters such as root distribution, depth and root diameter are obtained through CT scanning.

[0039] After testing various parameters of the vegetation 9, the raindrop splash erosion test can be started. The cured sample tube 3 is fixed upside down on the sample holder 11, so that the side of the soil 8 to be tested with the vegetation 9 planted is aligned with the nozzle 21.

[0040] First, the baffle 42 is placed in a position to block the water flow, and compressed air is injected into the pressure-resistant container 5 using the air compressor 6. The water in the pressure-resistant container 5 enters the water flow injection pipe 2 through the water pipe 51 and is ejected from the nozzle 21. Due to the baffle 42, the water flow cannot impact the soil to be tested 8. The air volume of the air compressor 6 is adjusted to stabilize the water flow.

[0041] The baffle 42 is controlled to rotate to a position where the water flow cannot be blocked, and the water flow sprayed from the nozzle 21 begins to impact the soil to be tested 8. At this time, the height of the sample tube 3 on the fixing frame 1 is adjusted to make it in a suitable position. The hydraulic erosion of the soil to be tested 8 begins.

[0042] The erosion test was carried out in stages, and the erosion time was recorded. During the test, a CT scanning device was used to non-destructively scan the soil to be tested 8 after erosion at different stages, and the scanned images were three-dimensionally reconstructed to obtain a series of images of the development process of the erosion morphology. Based on the CT scanned and reconstructed images, erosion characteristic parameters such as erosion amount and erosion depth can be obtained.

[0043] When designing the test, different types of soil and different compaction degrees can be selected when making samples according to different experimental objects. Different types of plants can also be selected for testing when planting vegetation. In erosion tests, different water flow rates can be set for different scenarios.

[0044] It should be noted that the parts not described in detail in this scheme are all prior art, and the above embodiments are only used to illustrate the present utility model, but the present utility model is not limited to the above embodiments. Any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present utility model fall within the protection scope of the present utility model.

Claims

1. A device for studying the erosion reduction effect of vegetation in raindrop splash erosion, characterized in that: The invention comprises a splash test device and a water pressure control device. The splash test device comprises a fixed frame (1), a water jet pipe (2) arranged below the fixed frame (1), and a sample tube (3) arranged above the fixed frame (1). The water jet pipe (2) is arranged vertically, and a nozzle (21) is arranged at the top of the water jet pipe (2). The sample tube (3) is used to load soil (8) to be tested planted with vegetation (9). The opening of the sample tube (3) is arranged downward and is located directly above the nozzle (21). A water retaining mechanism (4) for shielding water flow is also arranged between the nozzle (21) and the sample tube (3) on the fixed frame (1). The water retaining mechanism (4) can intermittently prevent the water flow from impacting the soil to be tested (8). The water pressure control device comprises a pressure-resistant container (5) and an air compressor (6); the bottom of the pressure-resistant container (5) is connected to the water inlet of the water jetting pipe (2) through a water pipe (51); the air outlet of the air compressor (6) is connected to the air inlet of the pressure-resistant container (5), and is used to generate pressure in the pressure-resistant container (5) so that water is jetted out through a nozzle (21).

2. A device for studying the erosion reduction effect of vegetation in raindrop splash erosion as claimed in claim 1, characterized in that: The water retaining mechanism (4) comprises a rotating shaft (41) rotatably arranged on a fixed frame (1) and a baffle (42) fixedly connected to the rotating shaft (41); the rotating shaft (41) is arranged parallel to the water jetting pipe (2); the baffle (42) is perpendicular to the rotating shaft (41); the rotating shaft (41) is rotated so that the baffle (42) is located directly above the nozzle (21) to block the water flow; the rotating shaft (41) is rotated so that the baffle (42) is moved away from directly above the nozzle (21) to allow the water flow to continue to impact the soil (8) to be tested in the sample tube (3).

3. A device for studying the erosion reduction effect of vegetation in raindrop splash erosion as claimed in claim 1, characterized in that: A weight detection device (7) is provided below the pressure-resistant container (5) for detecting the amount of remaining water in the water tank.

4. The device for studying the erosion reduction effect of vegetation in raindrop splash erosion as claimed in claim 1, characterized in that: A sample holder (11) with adjustable position is provided on the fixing frame (1), and the sample tube (3) is fixedly connected to the sample holder (11). The distance between the sample tube (3) and the nozzle (21) can be adjusted by adjusting the vertical height of the sample holder (11).

5. The device for studying the erosion reduction effect of vegetation in raindrop splash erosion as claimed in claim 2, characterized in that: The rotating shaft (41) is driven to rotate by a motor, and the water flow can be quickly cut off or restored by controlling the motor.

6. The device for studying the erosion reduction effect of vegetation in raindrop splash erosion as claimed in claim 3, characterized in that: The weight detection device (7) is an electronic scale.

7. The device for studying the erosion reduction effect of vegetation in raindrop splash erosion as claimed in claim 1, characterized in that: The inner diameter of the nozzle (21) orifice is 0.8 to 1.0 mm.

8. The device for studying the erosion reduction effect of vegetation in raindrop splash erosion as claimed in claim 1, characterized in that: The device also includes a CT scanning device for real-time observation and recording of the development and evolution of the tested soil (8) under water erosion.

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