Farmland ecological drainage method and regulating device thereof

Abstract

The application discloses a farmland ecological drainage method and a regulating device thereof, and belongs to the technical field of agricultural drainage and disaster reduction. The farmland ecological drainage method is a drainage method for improving the ecological environment of farmland by regulating water movement among and inside farmland, a ditch and a pond weir. The farmland ecological drainage method is realized by ecologicalization of a drainage concept, ecologicalization of a drainage engineering configuration and ecologicalization of drainage operation management. The farmland ecological drainage method adopts a drainage ecological flow regulation method. The drainage ecological flow regulation method controls the field drainage ecological flow speed, the ditch discharge ecological flow speed, the ditch-pond exchange ecological flow speed or the external drainage ecological flow speed to relieve the ecological function deterioration of farmland caused by waterlogging, salinization and nitrogen and phosphorus loss pollution. The application takes the ecological drainage flow speed as a starting point, and proposes an ecological drainage regulation criterion, an ecological flow regulation device and a flow calculation method for coping with waterlogging disasters, salinization hazards and non-point source pollution, and meets the dual demands of production and ecology.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of agricultural drainage and disaster mitigation, and particularly relates to a farmland ecological drainage method and a regulating device thereof. BACKGROUND

[0002] Agricultural waterlogging disasters, saline hazards and soil pollution seriously restrict China's grain production and ecological safety. Farmland drainage effectively alleviates crop waterlogging stress, efficiently leaches soil salinity and repairs soil pollution by changing the water movement process. This traditional drainage engineering only considers human production needs, but ignores the health and sustainable development of farmland ecosystems. When free drainage is carried out without control, it may cause ecological drought in the later period and aggravate non-point source pollution due to the disordered discharge of nutrient salts.

[0003] Therefore, how to provide a farmland drainage method that takes into account production and ecology, and upgrades the traditional farmland drainage technology according to the ecological safety requirements, especially for the ecological flow regulation of field underground pipe drainage, is a key technical problem to be solved by those skilled in the art. SUMMARY

[0004] Therefore, the present application provides a farmland ecological drainage method and a regulating device thereof to solve the problem of insufficient farmland drainage engineering technology caused by waterlogging, saline hazards and non-point source pollution hazards in the prior art.

[0005] In order to achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0006] According to a first aspect of the present application, a farmland ecological drainage method is provided, which is a drainage method for improving the ecological environment of farmland by regulating the water movement between and within farmland, channels and ponds. The farmland ecological drainage method is realized by ecologicalization of drainage concept, ecologicalization of drainage engineering configuration and ecologicalization of drainage operation management. The farmland ecological drainage method adopts a drainage ecological flow regulation method, which alleviates the deterioration of ecological function caused by waterlogging, saline hazards and nitrogen and phosphorus loss pollution by controlling the field drainage ecological flow rate, the channel discharge ecological flow rate, the channel-pond exchange ecological flow rate or the external drainage ecological flow rate.

[0007] Further, the drainage ecological flow regulation method comprises the following steps:

[0008] S1: Formulate a field drainage ecological flow rate regulation criterion according to the drainage purpose; wherein the drainage purpose is waterlogging prevention, salt washing and alkali control, nitrogen and phosphorus loss pollution prevention and control, or soil remediation;

[0009] S2: Based on the purpose of waterlogging prevention, formulate a first regulation criterion, which is an increase in speed and flow in the main drainage period and a decrease in speed and flow in the late period;

[0010] S3: Formulating a second regulation criterion based on the purpose of salt treatment and alkali treatment, the second regulation criterion being early speed reduction and flow reduction and late speed increase and flow increase, experiencing three regulation processes of zero-speed salt immersion, medium-speed salt separation and rapid salt removal, and three regulation speeds of speed reduction, constant speed and speed increase;

[0011] S4: Formulating a third regulation criterion based on the purpose of nitrogen and phosphorus loss pollution prevention and control, the third regulation criterion being to determine the critical flow rate according to the key pollutant emission rule and the principle of minimum comprehensive load, and to adopt the speed reduction and flow reduction criterion.

[0012] According to the second aspect of the present application, a farmland ecological drainage regulation device is provided for realizing the farmland ecological drainage method described in any one of the above, comprising a fixed connection member, a scale slide and a variable speed rotating member, one end of the fixed connection member is sleeved outside the underground pipe, the other end of the fixed connection member is sleeved outside the first end portion of the scale slide, the variable speed rotating member is rotationally connected outside the second end portion of the scale slide, the farmland ecological drainage regulation device controls the regulation speed by changing the rotation angle γ of the variable speed rotating member outside the scale slide, and calculates the average ecological flow rate of drainage under the condition of speed reduction according to the first algorithm and calculates the average ecological flow rate of drainage under the condition of speed increase according to the second algorithm.

[0013] Further, the variable speed rotating member comprises a first pipe, a transition pipe and a second pipe, the first pipe is rotationally connected outside the second end portion of the scale slide, the transition pipe is arranged between the first pipe and the second pipe, the transition pipe is an arc-shaped pipe, and the arc radius of the transition pipe is the same as the diameter of the underground pipe.

[0014] Further, the fixed connection member comprises a fixed pipe and a support structure, the fixed pipe is arranged between the underground pipe and the scale slide, the support structure is arranged at the bottom of the fixed pipe, and the outer diameter of the fixed pipe is equal to the inner diameter of the underground pipe.

[0015] Further, the scale slide comprises an insert and a sliding piece, the other end of the fixed connection member is sleeved outside the insert, the first pipe is sleeved outside the sliding piece, a scale disc is arranged outside the sliding piece and extends outward, and the first pipe abuts against the scale disc.

[0016] Further, the scale disc is marked with 0-360° scale lines, and the scale lines are arranged in the clockwise direction with the vertically upward scale line as the 0 scale line.

[0017] Further, a fixing piece is further arranged, the fixing piece is slidably arranged on the first pipe, the scale disc is provided with grooves at corresponding positions in sequence, and the fixing piece is clamped in the grooves.

[0018] Furthermore, the first algorithm is as follows:

[0019] ;

[0020] Among them, Q e The average ecological flow velocity for drainage. H represents the effective length of the variable speed component, i.e., the length of the second pipe. t The burial depth of the underground pipe is the vertical distance from the ground surface to the pipe's outlet; Q s The free drainage velocity in the state of no increase or decrease in velocity of the underground pipe drainage is determined by the layout of the underground pipe and the soil properties; α is the angle formed by the center lines of the first pipe and the second pipe, and the angle α is 30-90°; the rotation angle γ is 0-90° or 270-360°.

[0021] Furthermore, the second algorithm is as follows:

[0022] ;

[0023] Among them, Q e C represents the average ecological flow velocity of the drainage. sd The flow boosting coefficient, H, was obtained experimentally. d The height difference between the outlet of the concealed pipe and the water surface of the receiving drainage ditch; Q represents the effective length of the speed-changing component, i.e., the length of the second pipe. s The free drainage velocity in the state of no increase or decrease in velocity of the underground pipe drainage is determined by the layout of the underground pipe and the soil properties; α is the angle formed by the center lines of the first pipe and the second pipe, and the angle α is 30-90°; the rotation angle γ is 90-270°.

[0024] The present invention has the following advantages:

[0025] This invention controls the speed of farmland drainage by changing the rotation angle γ of the variable speed component outside the graduated slide, overcoming the problem that traditional farmland drainage only considers crop production and ignores ecological needs. Taking ecological drainage flow velocity as a starting point, it proposes ecological drainage regulation principles to address floods, droughts, salinity, and non-point source pollution. It also invents an ecological flow regulation device and flow calculation method, taking into account both production and ecological needs. This farmland ecological drainage system can effectively alleviate ecological degradation caused by floods, droughts, salinity, and non-point source pollution. Attached Figure Description

[0026] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0027] The structures, proportions, sizes, etc. shown in the specification are only used to cooperate with the content disclosed in the specification for understanding and reading by those skilled in the art, and are not used to limit the conditions for implementing the application, so they do not have technical significance. Any modification of structure, change of proportion relationship or adjustment of size, which does not affect the effects and purposes that can be achieved by the application, should still fall within the scope of the disclosed technology.

[0028] Figure 1 The flow chart of the ecological flow regulation method for drainage provided by the application is shown in the figure.

[0029] Figure 2 The structural schematic diagram of the ecological drainage regulation device for farmland provided by the application is shown in the figure.

[0030] Figure 3 The cross-sectional view of the ecological drainage regulation device for farmland provided by the application is shown in the figure.

[0031] Figure 4 The Figure 3 The local enlarged view of A in the figure.

[0032] In the figure:

[0033] 1 fixed member; 101 fixed pipe; 102 support structure; 2 scale slide; 201 plug-in; 202 slide; 3 variable speed rotating member; 301 first pipe; 302 transition pipe; 303 second pipe; 4 dial; 5 fixed part; 6 groove; 7 underground pipe. DETAILED DESCRIPTION

[0034] The embodiments of the application are described below by specific examples, and those skilled in the art can easily understand other advantages and effects of the application from the disclosed content. Obviously, the described examples are part of the examples of the application, not all. Based on the examples in the application, all other examples obtained by those skilled in the art without creative labor fall within the scope of the application.

[0035] The application provides a farmland ecological drainage method, which is a drainage method for improving the ecological environment of farmland by regulating the water movement between farmland, ditch and pond weir and inside the farmland, changing the water and soil environment of farmland to maintain sustainable production and ecological diversity, and avoiding ecological function deterioration caused by waterlogging, salinization, pollution, etc. in farmland.

[0036] Farmland ecological drainage includes ecologicalization of drainage concept, ecologicalization of drainage engineering configuration and ecologicalization of drainage operation management. Drainage ecological flow regulation is the key to realize the ecologicalization of farmland drainage system, which specifically involves farmland drainage ecological flow rate, ditch drainage ecological flow rate, ditch-pond exchange ecological flow rate, external drainage ecological flow rate and their matching. The invention gives a farmland drainage ecological flow regulation method applied to the underground pipe, as shown in Figure 1 , which includes the following steps:

[0037] S1: Formulate farmland drainage ecological flow rate regulation criteria according to drainage purposes; wherein the drainage purposes are flood control, salt washing and alkali control, nitrogen and phosphorus loss pollution prevention and control, or soil remediation;

[0038] S2: Based on the purpose of flood control, formulate the first regulation criteria, which is the increase of flow rate in the main drainage period and the decrease of flow rate in the late period;

[0039] S3: Based on the purpose of salt washing and alkali control, formulate the second regulation criteria, which is the decrease of flow rate in the early period and the increase of flow rate in the late period, which goes through three regulation processes of zero-speed salt immersion, medium-speed salt precipitation and rapid salt removal, and three regulation speeds of decreasing speed, constant speed and increasing speed;

[0040] S4: Based on the purpose of nitrogen and phosphorus loss pollution prevention and control, formulate the third regulation criteria, which is to determine the critical flow rate according to the key pollutant emission rule and the principle of minimum comprehensive load, and adopt the decrease of flow rate criteria.

[0041] Farmland underground pipe ecological drainage can be divided into flood control ecological flow rate, salt washing and alkali control ecological flow rate, nitrogen and phosphorus loss pollution control ecological flow rate, or soil remediation ecological flow rate according to different purposes. The ecological flow rate for each problem needs to formulate corresponding regulation criteria. Flood control requires to quickly remove the excess water hazards of surface and underground excess water and the late water shortage hazards, and requires to implement the ecological regulation criteria of increasing flow rate in the main drainage period and decreasing flow rate in the late period; the ecological flow rate of salt washing and alkali control should implement the variable flow rate regulation criteria of slow decrease of flow rate in the early period and rapid increase of flow rate in the late period, especially the invention of three-stage regulation method of salt washing and alkali control ecological flow rate: zero-speed salt immersion, medium-speed salt precipitation and rapid salt removal, which usually goes through three regulation processes of decreasing speed, constant speed and increasing speed; the ecological flow rate of pollution control determines the critical flow rate according to the key pollutant emission rule and the principle of minimum comprehensive load, and usually adopts the regulation criteria of decreasing speed.

[0042] The free drainage flow of underground pipe is mainly determined by the soil water conductivity, the buried depth and the spacing of underground pipe, which is difficult to regulate according to the change demand of farmland ecological flow rate. In order to meet the needs of flood control, salt and alkali control and pollution control, the ecological flow rate is increased or decreased, and a farmland ecological drainage regulation device and calculation method are further invented.

[0043] A farmland ecological drainage regulation device, as shown inFigure 2 and 3 As shown, the device includes a fixed connecting member 1, a graduated slide 2, and a speed-changing rotating component 3. One end of the fixed connecting member 1 is fitted onto the outside of the concealed pipe 7, and the other end of the fixed connecting member 1 is fitted onto the outside of the first end of the graduated slide 2. The speed-changing rotating component 3 includes a first pipe 301, a transition pipe 302, and a second pipe 303. The first pipe 301 is rotatably connected to the outside of the second end of the graduated slide 2, and the transition pipe 302 is located between the first pipe 301 and the second pipe 303. The transition pipe 302 is an arc-shaped pipe, and the radius of the arc of the transition pipe 302 is the same as the diameter of the concealed pipe 7. The centerlines of the first pipe 301 and the second pipe 303 form an angle α, the angle of which is 30-90°.

[0044] The fixing component 1 includes a fixed pipe 101 and a supporting structure 102. The outer diameter of the fixed pipe 101 is equal to the inner diameter of the concealed pipe 7. The fixed pipe 101 is located between the concealed pipe 7 and the graduated slide 2. The supporting structure 102 is located at the bottom of the fixed pipe 101 and supports the fixed pipe 101. The graduated slide 2 includes an insert 201 and a slider 202. The other end of the fixing component 1 is fitted over the insert 201, and the first pipe 301 is fitted over the slider 202. A graduated dial 4 extends outward from the outside of the slider 202, and the first pipe 301 rests on the graduated dial 4. The graduated dial 4 is engraved with graduations from 0 to 360°, with the vertically upward graduation line as the 0 graduation line and arranged clockwise. The first pipe 301 can rotate around the slider 202, and its rotation angle γ can be calculated from the graduation value on the graduated dial 4. When the rotation angle γ is 0-90° or 270-360°, the drainage ecological flow velocity is under the condition of decreasing speed; when the rotation angle γ is 90-270°, the drainage ecological flow velocity is under the condition of increasing speed.

[0045] like Figure 4 As shown, it also includes a fixing member 5. The fixing member 5 is slidably mounted on the first pipe 301, and grooves 6 are sequentially provided at the corresponding positions of the scale lines on the dial 4. The fixing member 5 is engaged in the grooves 6. When the first pipe 301 rotates outside the slider 202, when it rotates to the corresponding position, the fixing member 5 is pushed to fix it in the groove 6, thereby fixing the position of the first pipe 301 and preventing the first pipe 301 from being affected by the rotation of the water flow force, thus affecting the ecological flow rate of the drainage.

[0046] An ecological flow regulation device is installed on farmland, so that one end of the fixed component is sleeved outside the culvert. The rotation angle γ of the variable speed component outside the scale slide is changed to control the speed regulation. The average ecological flow velocity of drainage under the deceleration condition is calculated according to the first algorithm, and the average ecological flow velocity of drainage under the acceleration condition is calculated according to the second algorithm.

[0047] The first algorithm is:

[0048] ;

[0049] wherein Q e is the average ecological flow rate of drainage, is the effective length of the variable-speed rotating member, i.e., the length of the second pipeline 303; H t is the buried depth of the buried pipe, i.e., the vertical distance from the ground surface to the outlet of the buried pipe; Q s is the free drainage flow rate of the buried pipe drainage in the non-increased or decreased speed state, which is determined by the layout of the buried pipe and the soil properties; and α is the included angle formed by the center lines of the first pipeline and the second pipeline, the included angle α being 30-90°; and the rotation angle γ is 0-90° or 270-360°.

[0050] The second algorithm is:

[0051] ;

[0052] wherein Q e is the average ecological flow rate of drainage, C sd is the flow-increasing coefficient, which is obtained by experiment; H d is the height difference between the outlet of the buried pipe and the water surface of the receiving drainage ditch; is the effective length of the variable-speed rotating member, i.e., the length of the second pipeline; Q s is the free drainage flow rate of the buried pipe drainage in the non-increased or decreased speed state, which is determined by the layout of the buried pipe and the soil properties; and α is the included angle formed by the center lines of the first pipeline and the second pipeline, the included angle α being 30-90°; and the rotation angle γ is 90-270°.

[0053] The contents of the farmland ecological drainage, which are ecologicalized in concept, engineering configuration and operation management, are embodied as three parts of ecological regulation criteria, ecological regulation devices and ecological flow calculation.

[0054] Based on the efficient and uniform desalination of salt control, depression and water saving of the soil water and salt migration mechanism and its irrigation and drainage coordination mechanism, three-stage regulation criteria of zero-speed salt immersion, medium-speed salt precipitation and rapid desalination are proposed. The time proportion of the three stages of decreased speed, constant speed and increased speed can be embodied as 3:2:1, the flow rate in the decreased speed stage is less than 1 / 3 of the constant speed, and the flow rate in the increased speed stage is at least 1.2 times of the constant speed.

[0055] In order to implement the regulation criteria, regulation devices are developed. The included angle α of the variable-speed rotating member is perpendicular to the buried pipe, and the effective length is not less than the buried depth of the buried pipe; the rotation angle γ of the zero-speed salt immersion stage is 0°, the rotation angle γ of the medium-speed salt precipitation stage is 60°, and the rotation angle γ of the rapid desalination stage is 180°.

[0056] Combined with the regulation criterion and the implementation device, the ecological flow rate is calculated. The ecological flow rate of the zero-speed salt immersion stage is 0, the ecological flow rate of the medium-speed salt precipitation stage is , and the ecological flow rate of the fast desalination stage is . The durations of the three stages can be selected as 3 days, 2 days and 1 day respectively.

[0057] The application controls the regulation speed by changing the rotation angle γ of the variable-speed rotating member outside the scale slide, and breaks the problem that the traditional farmland drainage only considers crop production and ignores ecological demand. Taking the ecological drainage flow rate as a starting point, the ecological drainage regulation criterion for coping with flood and drought disasters, saline-alkali hazards and non-point source pollution is proposed, the ecological flow regulation device and the flow calculation method are invented, the dual demands of production and ecology are considered, and the farmland ecological drainage system can effectively alleviate the ecological deterioration caused by flood and drought, saline-alkali and non-point source pollution.

[0058] Although the application has been fully described in the foregoing by way of general description and specific embodiments, some modifications or improvements can be made on the basis of the application, which is obvious to those skilled in the art. Therefore, these modifications or improvements made on the basis of not deviating from the spirit of the application all belong to the scope of protection required by the application.

Claims

1. An agricultural field eco-drainage method, characterized by, The farmland ecological drainage method adopts a drainage ecological flow regulation method, and the drainage ecological flow regulation method comprises the following steps: S1: formulating a field drainage ecological flow speed regulation criterion according to a drainage purpose; wherein the drainage purpose is flood prevention, salt washing and alkali treatment, nitrogen and phosphorus loss pollution prevention and control, or soil remediation; S2: based on the purpose of flood prevention, a first regulation criterion is formulated, which is an increase in speed and flow in the main drainage period and a decrease in speed and flow at the end; S3: based on the purpose of salt washing and alkali treatment, a second regulation criterion is formulated, which is a decrease in speed and flow in the early stage and an increase in speed and flow in the late stage, which experiences three regulation processes of zero-speed salt immersion, medium-speed salt separation and rapid desalination, and three regulation speeds of decreasing speed, constant speed and increasing speed; S4: based on the purpose of nitrogen and phosphorus loss pollution prevention and control, a third regulation criterion is formulated, which is to determine the critical flow speed according to the key pollutant emission rule and the principle of minimum comprehensive load, and to adopt the speed reduction and flow reduction criterion. The farmland ecological drainage regulation device used in the drainage ecological flow regulation method comprises a fixed member (1), a scale slide (2) and a variable speed rotating member (3), one end of the fixed member (1) is sleeved outside the underground pipe (7), the other end of the fixed member (1) is sleeved outside the first end portion of the scale slide (2), the variable speed rotating member (3) is rotatably connected outside the second end portion of the scale slide (2), the farmland ecological drainage regulation device controls the regulation speed by changing the rotation angle γ of the variable speed rotating member (3) outside the scale slide (2), and calculates the average ecological flow speed of drainage under the condition of speed reduction according to the first algorithm, and calculates the average ecological flow speed of drainage under the condition of speed increase according to the second algorithm.

2. The method of claim 1, wherein, The farmland ecological drainage method is a drainage method for improving the ecological environment of farmland by regulating the water movement between and inside farmland, ditches and ponds, which is realized by ecologicalization of drainage concept, ecologicalization of drainage engineering configuration and ecologicalization of drainage operation and management. The drainage ecological flow regulation method relieves the ecological function deterioration of farmland caused by flood, salt and alkali and nitrogen and phosphorus loss pollution by controlling the ecological flow speed of field drainage, ditch discharge, ditch-pond exchange or external discharge.

3. An agricultural field ecological drainage regulation device for implementing the agricultural field ecological drainage method according to any one of claims 1-2, characterized in that, The variable speed rotating member (3) comprises a first pipeline (301), a transition pipeline (302) and a second pipeline (303), the first pipeline (301) is rotatably connected outside the second end portion of the scale slide (2), the transition pipeline (302) is arranged between the first pipeline (301) and the second pipeline (303), the transition pipeline (302) is an arc-shaped pipeline, and the arc radius of the transition pipeline (302) is the same as the diameter of the underground pipe (7).

4. The farmland ecological drainage regulation device according to claim 3, characterized in that, The fixed member (1) comprises a fixed pipeline (101) and a support structure (102), the fixed pipeline (101) is arranged between the underground pipe (7) and the scale slide (2), the support structure (102) is arranged at the bottom of the fixed pipeline (101), and the outer diameter of the fixed pipeline (101) is equal to the inner diameter of the underground pipe (7).

5. The farmland ecological drainage regulation device according to claim 3, characterized in that, The scale slide (2) comprises an insert (201) and a sliding piece (202), the other end of the fixed connection member (1) is sleeved outside the insert (201), the first pipeline (301) is sleeved outside the sliding piece (202), a scale disc (4) is arranged outside the sliding piece (202) and extends outward, and the first pipeline (301) abuts against the scale disc (4).

6. The farmland ecological drainage regulation device according to claim 5, wherein, The scale disc (4) is marked with scale lines of 0-360°, and the scale lines are arranged in a clockwise direction with a vertical upward scale line as a 0 scale line.

7. The farmland ecological drainage regulation device according to claim 6, wherein, Further comprising a fixing piece (5), the fixing piece (5) is slidably arranged on the first pipeline (301), and the scale disc (4) is sequentially provided with recesses (6) at corresponding positions of the scale lines.

8. The farmland ecological drainage regulation device according to claim 3, wherein, The first algorithm is: ； wherein Q e is the average ecological flow rate of drainage, is the effective length of the variable speed rotating member, i.e. the length of the second pipe; H t is the buried depth of the pipe, i.e. the vertical distance from the ground surface to the outlet of the pipe; Q s is the free drainage flow rate of the pipe drainage in the non-accelerating or decelerating state, which is determined by the pipe layout and soil properties; α is the included angle formed by the center lines of the first pipe and the second pipe, and the angle of the included angle α is 30-90°; the rotation angle γ is 0-90° or 270-360°.

9. The farmland ecological drainage regulation device according to claim 3, wherein, The second algorithm is: ； wherein Q e is the average ecological flow rate of drainage, C sd is the flow coefficient, obtained by experiment; H d is the height difference between the outlet of the buried pipe and the water surface of the receiving drainage ditch; is the effective length of the variable speed rotating member, i.e. the length of the second pipe; Q s is the free drainage flow rate of the buried pipe drainage without speed increase or decrease, determined by the buried pipe layout and soil properties; α is the included angle formed by the center lines of the first pipe and the second pipe, the angle α is 30-90°; the rotation angle γ is 90-270°.

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