Device and method suitable for continuous monitoring of dynamic changes of riparian zone deepwater sediments and key environment indexes

Abstract

The invention belongs to the technical field of environment monitoring, and particularly discloses a device and method suitable for continuous monitoring of dynamic changes of riparian zone deepwater sediment and key environment indexes, and the device comprises an upper computer control unit, an underwater auxiliary unit and an acquisition unit; the underwater auxiliary unit and the acquisition unit are arranged underwater, the underwater auxiliary unit is in signal connection with the upper computer control unit so as to receive a control instruction sent by the upper computer control unit, and the underwater auxiliary unit is in signal connection with the acquisition unit so as to receive a control instruction sent by the upper computer control unit. The control unit is used for controlling the acquisition unit to work and receiving data transmitted by the acquisition unit according to the control instruction of the underwater auxiliary unit and the control instruction of the upper computer control unit, and the upper computer control unit is used for receiving and displaying the data transmitted by the acquisition unit. According to the invention, high-precision and high-frequency monitoring and batch data acquisition of deepwater sediment key environment indexes and interstitial water can be realized.

Description

Technical Field

[0001] The invention relates to the technical field of environmental monitoring, and in particular to a device and method suitable for continuous monitoring of dynamic changes of deep-water sediments in riverbank zones and key environmental indicators. Background Art

[0002] Sediments are an important place for the enrichment and transformation of lake and reservoir biogenic elements. They are very sensitive to environmental changes and can be stably preserved, and can reflect the biogeochemical cycle and environmental evolution of lakes and reservoirs. Therefore, accurately obtaining sediment dynamics and continuous changes in key environmental indicators is of great significance for studying lake and reservoir environmental changes and material environmental behavior.

[0003] At present, sediment monitoring adopts the method of collecting first and then analyzing in the laboratory, or using a single indicator sensor for point-type continuous monitoring. Regular survey is still a widely used sediment monitoring method, including sediment collectors, thin film gradient diffusion gradient technology, underwater sampling robots and other in-situ collection devices. This method requires a large number of personnel to conduct on-site investigations regularly, properly store and transport the samples, and transport them back to the laboratory for analysis in a timely manner. It often causes problems such as high cost of obtaining sediment samples, low frequency of acquisition, and great interference to the samples during the processing process. In addition, laboratory testing can easily lead to distortion of sediment environmental indicators. Environmental sensors reflect the corresponding environmental parameters through optical, electrical, acoustic, chemical and other signals, and provide continuous high-precision in-situ monitoring data for the monitoring medium. At present, the application indicators of environmental sensors in sediment monitoring are relatively wide. For example, the Sequoia LISST sensor uses laser diffraction technology to measure sediment particle size distribution and concentration; the Aanderaa Optode4835 sensor is based on the principle of optical fluorescence quenching to monitor the dissolved oxygen content of marine and freshwater sediments. However, due to the differences in the working principles and transmission signals of different sensor elements, it is difficult to integrate and intelligentize sediment environmental monitoring indicators. In addition, existing sediment sensors usually send monitoring instructions and receive and record data signals through handheld terminals, which has low data acquisition efficiency. Moreover, when conducting deep-water monitoring, long data transmission can easily lead to data loss or distortion, which hinders sediment monitoring or research work.

[0004] Therefore, existing sediment monitoring equipment has problems such as low data acquisition efficiency, distorted ex situ sample data, easy contamination during sample processing, and signal loss or distortion caused by long-distance data transmission, which makes it difficult to meet the existing research needs of sediments. Aiming at the shortcomings of current sediment monitoring methods and devices, the present invention proposes an integrated automatic working device with a master-slave network control structure and coordinated simultaneous operation of multiple sensor elements to achieve interstitial water collection, which is of great significance to the environmental monitoring of riverbanks / deepwater sediments and the study of biochemical processes. Summary of the invention

[0005] In view of the above-mentioned deficiencies in the prior art, the object of the present invention is to provide a device and method suitable for continuous monitoring of the dynamic changes of deep-water sediments in the riparian zone and key environmental indicators, so as to achieve high-precision, high-frequency monitoring and batch data acquisition of key environmental indicators of the riparian zone / deep-water sediments.

[0006] In order to achieve the above object, the present invention adopts the following technical scheme:

[0007] According to a first aspect of the present invention, there is provided a device suitable for continuous monitoring of dynamic changes of deep-water sediments and key environmental indicators in a riverbank zone, the device comprising a host computer control unit, an underwater auxiliary unit and a collection unit;

[0008] The underwater auxiliary unit and the acquisition unit are arranged underwater, the underwater auxiliary unit is connected to the host computer control unit by signal, so as to receive the control instruction issued by the host computer control unit, the underwater auxiliary unit is connected to the acquisition unit by signal, so as to control the acquisition unit to work according to the control instruction and receive the data transmitted by the acquisition unit, the acquisition unit includes a voltage detection element, a current detection element, a water leakage detection element, a pan-tilt camera, an underwater light, a temperature sensor element, a conductivity sensor element, a dissolved oxygen sensor element, a mud level meter and a gap water sampler;

[0009] The host computer control unit is used to receive and display the data transmitted by the acquisition unit;

[0010] Furthermore, the underwater auxiliary unit can independently control the operation of the acquisition unit and record data without being separated from the upper control unit.

[0011] Further, the interstitial water sampler comprises an interstitial water enrichment unit, a water extraction unit and a sample collection unit;

[0012] The interstitial water enrichment unit is connected to the sample collection unit via the pumping unit;

[0013] The interstitial water enrichment unit includes an outer layer infiltration, an inner layer infiltration, an interstitial water tank and a first water pipe; wherein the outer layer infiltration, the inner layer infiltration and the interstitial water tank are connected in sequence from the outside to the inside, one end of the first water pipe is connected to the interstitial water tank, and the other end is connected to the pumping unit.

[0014] Furthermore, the pumping unit includes a second water pipe, an electromagnetic three-way valve, a syringe barrel, a syringe piston, a lower plate, a middle plate, an upper plate, a support shaft and an electric telescopic rod; the electromagnetic three-way valve has three ports, namely a first port, a second port and a third port, one end of the second water pipe is connected to the third port, the other end of the second water pipe is connected to the first water pipe, the second port is connected to the sample collection unit, and the first port pipeline is connected to the liquid end of the syringe barrel; at least one support shaft is arranged between the lower plate and the middle plate, the syringe barrel is fixedly clamped by the lower plate and the middle plate, the syringe piston is arranged in the syringe barrel, the syringe piston is connected to the piston rod, one end of the piston rod is fixed to the lower end of the upper plate, the electric telescopic rod is fixed to the upper plate, and the telescopic end of the electric telescopic rod is connected to the middle plate.

[0015] Furthermore, a piston block is arranged on the upper plate, and the piston rod is arranged in the piston block and fixed by a nut.

[0016] Furthermore, the pumping unit also includes an electromagnetic switch, which is communicatively connected to the electromagnetic three-way valve; the pumping unit includes an electric control switch, which is communicatively connected to the electric telescopic rod.

[0017] Furthermore, the outer layer permeation and the inner layer permeation are mesh structures, which are filled with first gravel and second gravel respectively; wherein the particle size of the first gravel is larger than that of the second gravel.

[0018] Furthermore, the interstitial water tank is annular, a watertight bottom cover is provided at the bottom of the interstitial water tank, a top cover with a water outlet joint is provided at the top of the interstitial water tank, and the water outlet joint is connected to the first water conduit.

[0019] According to a second aspect of the present invention, a method for continuous monitoring of dynamic changes of deep-water sediments and key environmental indicators in a riparian zone is provided. Based on the apparatus as described above, the method comprises:

[0020] Determine the sediment deposition thickness and sediment scouring thickness of the monitoring area based on the flow velocity, water depth, water body width, sediment content, sediment starting velocity and sediment density of the monitoring area;

[0021] Determine the installation method of the underwater auxiliary unit and the collection unit in the above device according to the sediment deposition thickness and the sediment scouring thickness, and install the underwater auxiliary unit and the collection unit underwater in the determined installation method;

[0022] A host computer control unit is arranged in the onshore area of ​​the riverbank, and a watertight umbilical cable is used between the host computer control unit and the underwater auxiliary unit to complete electrical and signal transmission; the host computer control unit displays the working status of the collection unit, the data monitored by the collection unit, and controls the collection unit in real time.

[0023] Furthermore, according to the flow velocity, water depth, water body width, sediment content, sediment starting velocity and sediment density of the monitoring area, the sediment deposition thickness and sediment scouring thickness of the monitoring area are determined by the following formula:

[0024]

[0025] In the formula, H 沉 represents the thickness of sediment deposition, C s represents the sediment content of the water body, v represents the average flow velocity of the river, B represents the width of the water body, h p represents water depth, T represents equipment placement time, ρ represents sediment density, A represents bottom area, H 冲 Indicates the thickness of sediment scour.

[0026] Furthermore, the installation method of the underwater auxiliary unit and the acquisition unit is determined by the following method:

[0027] If the sediment deposition thickness is 0-20cm and the sediment scour thickness is 0-3cm, the installation method is to install the underwater auxiliary unit and the collection unit directly underwater;

[0028] If the sediment thickness is 20-50cm and the sediment scour thickness is 3-8cm, the installation method is to install a fixed bracket underwater and insert the watertight umbilical cable below 10cm below the sediment to install the underwater auxiliary unit and the acquisition unit;

[0029] If the sediment thickness is greater than 50 cm or the sediment scouring thickness is greater than cm, select other suitable monitoring points or add counterweights and install fixed brackets to install underwater auxiliary units and collection units underwater.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] 1. The device proposed in the present invention can realize high-precision, high-frequency monitoring and batch data acquisition of key environmental indicators of deep-water sediments and interstitial water, especially through the setting of interstitial water enrichment units, to achieve automatic collection of interstitial water.

[0032] 2. The method proposed in the present invention determines the installation method of underwater equipment according to the thickness of sediment deposition and the thickness of sediment scouring, can select effective monitoring points, and improve the working stability and service life of underwater equipment at the lowest cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0034] Figure 1 The present invention is a schematic diagram of the structure of a device suitable for continuous monitoring of dynamic changes of deep-water sediments and key environmental indicators in riverbank zones according to an embodiment of the invention.

[0035] Figure 2 Schematic diagram of the structure of a gap water sampler according to an embodiment of the present invention.

[0036] Figure 3 4 is a plan view of an interstitial water enrichment unit in an interstitial water sampler according to an embodiment of the present invention.

[0037] Figure 4 It is a stereoscopic diagram of an interstitial water enrichment unit in an interstitial water sampler according to an embodiment of the present invention.

[0038] Figure 5 The following is a diagram of the UI interface of the host computer control unit software according to an embodiment of the present invention.

[0039] Figure 6 A map of the Three Gorges Reservoir Riverbank Zone test area according to an embodiment of the present invention.

[0040] Figure 7 It is a schematic diagram of the assembly and deployment of the device according to an embodiment of the present invention; wherein A, the control module of the underwater control unit; B, the assembly of the underwater control unit and the acquisition unit; C, the field deployment.

[0041] Figure 8 1 is a display diagram of monitoring data according to an embodiment of the present invention; wherein, A, conductivity; B, temperature; C, nitrogen; D, phosphorus; E, potassium; F, dissolved oxygen; and G, mud level.

[0042] Reference numerals:

[0043] 100. Host computer control unit;

[0044] 200, underwater auxiliary unit; 201, underwater controller; 202, underwater storage power supply;

[0045] 300, acquisition unit; 301, voltage detection element; 302, current detection element; 303, water leakage detection element; 304, PTZ camera; 305, underwater light; 306, temperature sensor element; 307, conductivity sensor element; 308, dissolved oxygen sensor element; 309, mud level meter;

[0046] 310. Interstitial water sampler; 3110. Interstitial water enrichment unit; 3111. Outer layer penetration; 3112. Inner layer penetration; 3113. Interstitial water tank; 3114. First water conduit; 3115. Watertight bottom cover; 3120. Pumping unit; 31201. Second water conduit; 31202. Solenoid three-way valve; a. First port; b. Second port; c. Third port; 31203. Syringe barrel; 31204. Syringe piston; 31205. Lower plate; 31206. Middle plate; 31207. Upper plate; 31208. Support shaft; 31209. Electric telescopic rod; 31210. Piston rod; 31211. Piston block; 31212. Solenoid switch; 31213. Electric control switch; 31214. Hand-tightened blind nut; 3130. Sample collection unit. DETAILED DESCRIPTION

[0047] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0048] In the description of the present invention, unless otherwise specified, "plurality" means two or more than two; the orientations or positional relationships indicated by the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance.

[0049] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0050] The present invention will now be further described with reference to the accompanying drawings.

[0051] The embodiment of the present invention provides a device suitable for continuous monitoring of dynamic changes of deep-water sediments and key environmental indicators in riverbank zones, such as Figure 1 As shown, the device includes a host computer control unit 100, an underwater auxiliary unit 200 and a collection unit 300.

[0052] Among them, the underwater auxiliary unit 200 and the collection unit 300 are arranged underwater, the underwater auxiliary unit 200 is signal-connected with the host computer control unit 100 to receive the control instructions issued by the host computer control unit 100, the underwater auxiliary unit 200 is signal-connected with the collection unit 300 to control the collection unit 300 to work according to the control instructions and receive the data transmitted by the collection unit 300, the collection unit 300 includes a voltage detection element 301, a current detection element 302, a water leakage detection element 303, a pan-tilt camera 304, an underwater light 305, a temperature sensor element 306, a conductivity sensor element 307, a dissolved oxygen sensor element 308, a mud level meter 309 and a gap water sampler 310; the host computer control unit 100 is used to receive and display the data transmitted by the collection unit 300.

[0053] In this embodiment, the host computer control unit 100 is responsible for collecting the operator's control instructions, including setting the operating frequency of the sensor element, executing the operation of the interstitial water collector 310, switching the pan-tilt camera 304 and the underwater light 305, and other commands, and sending them to the underwater through the Ethernet via the interface board and the umbilical cable, while receiving the data transmitted by the underwater auxiliary unit 200 and displaying it on the monitoring interface.

[0054] Exemplarily, a communication module is respectively configured in the host control unit 100 and the underwater auxiliary unit 200, and the two communication modules are connected via an umbilical cable to establish a communication connection, thereby enabling information exchange between the host control unit 100 and the underwater auxiliary unit 200.

[0055] The underwater auxiliary unit 200 can be implemented as an auxiliary computer, for example. When the underwater auxiliary unit 200 and the collection unit 300 are assembled underwater, a watertight device is installed to ensure that the internal parts of each component are dry when working underwater. The underwater auxiliary unit 200 can include an underwater controller 201 and an underwater storage power supply 202, that is, a single controller structure with a storage / power supply system and a communication module is adopted, and its task is to control the collection unit (mud level meter 309, interstitial water collector 310, pan-tilt camera 304, dissolved oxygen sensor element 308 and underwater light 305, voltage detection element 301, current detection element 302, water leakage detection element 303, etc.) according to the control instruction, read and store the sensor element data, and communicate with the host computer control unit 100 through Ethernet. When deployed, the distance between the collection unit 300 and the underwater auxiliary control unit 200 is less than 5m to ensure the monitoring frequency and data transmission fidelity.

[0056] Exemplarily, the circuit and data interfaces of the umbilical cable and the sensor element all use customized watertight plugs to make them watertight when connected to the underwater auxiliary unit 200. The underwater auxiliary unit 200 is placed as a whole in a pressure-resistant sealed cabin equipped with a watertight plug to keep a dry environment when working underwater. The design specification of the watertight device is to work normally when it is 100 meters underwater. The watertight device is an existing structural component that can achieve watertightness, and its specific structure is not limited here in this embodiment.

[0057] When working, underwater equipment is susceptible to water pressure, sediment disturbance, etc., especially optical and acoustic sensor elements. Therefore, the sensor elements of the acquisition unit should choose electrical working principle elements as much as possible, and add watertight design to ensure that it can withstand high-pressure environment. In order to ensure the consistency of current, voltage signals and data signals between the underwater auxiliary control unit, acquisition unit and host control unit, corresponding DC / DC, DC / AC power modules and communication modules need to be installed. The main hardware parameters are as follows:

[0058] 1) Temperature and conductivity sensor elements (i.e., temperature sensor element 306 and conductivity sensor element 307). Temperature and conductivity sensor elements based on the principle of FDR technology (Frequency Domain Reflectometry) are selected. They have good anti-electromagnetic interference capability, can provide stable temperature and conductivity data in complex underwater environments, and reduce the impact of environmental noise on measurement results. The maximum data reading interval of this element is 30s, and it can work continuously for a long time, meeting the high-frequency, high-precision, and long-term continuous sediment monitoring requirements of the equipment. Its specifications are shown in Tables 1 and 2.

[0059] Table 1 Detailed parameters of high resolution temperature sensor element

[0060] Serial number parameter Specification 1 Range -20～80℃ 2 Accuracy 0.1℃ 3 Communication ModBusRTU Protocol

[0061] Table 2 Detailed parameters of high resolution conductivity sensor element

[0062] Serial number parameter Specification 1 Range 0~2000us / cm 2 Accuracy 1us / cm 3 Communication ModBusRTU Protocol

[0063] 2) Dissolved oxygen sensor element 308. A temperature-corrected thermistor sensor element is used to measure the dissolved oxygen content in the sediment. The maximum data reading interval of this element is 14 seconds, and it can be monitored continuously for a long time. Its specifications are shown in Table 3.

[0064] Table 3 Detailed parameters of high resolution dissolved oxygen sensor element

[0065] Serial number parameter Specification 1 Range 0～100％ 2 Accuracy 0.1％ 3 Communication SDI-12 Protocol

[0066] 3) Mud level meter 309. A mud level sensor based on digital signal processing technology and underwater ultrasonic echo algorithm is selected to monitor the change of sediment thickness in the study area in real time. When measuring the change of sediment thickness, the ultrasonic sensor is placed in the water bottom or at a certain position underwater in the forward / reverse direction, and the change of sediment thickness is calculated by using the fixed sound speed of ultrasound in water and the time from ultrasound emission to reception. The maximum data reading interval of this component is 1s, and it can monitor continuously for a long time. Its specifications are shown in Table 4.

[0067] Table 4 Detailed parameters of high resolution mud level meter

[0068] Serial number parameter Specification 1 Range 0.015～6m 2 Accuracy ±2mm 3 Communication ModBusRTU Protocol

[0069] 4) PTZ camera 304. The PTZ camera 304 installed underwater is a key device for observing underwater vegetation, sediment dynamics, and equipment working conditions. The selected low-light high-definition Sony IMX322 sensor uses a large sensor size (1 / 2.9″) and a relatively low pixel count (2MP, 1080p), which can provide good low-light performance, color processing capabilities, onboard video compression capabilities, and will not impose too much burden on the control unit.

[0070] 5) Underwater light 305. When the equipment is working underwater, the surrounding light is dim. At this time, the camera needs to use underwater lighting to compensate for the external light. The underwater light 305 should be selected to avoid noise on the camera screen. The main specifications are shown in Table 5.

[0071] Table 5 Detailed parameters of underwater lighting

[0072] Serial number parameter Specification 1 Supply voltage 10～48V 2 Light color temperature 6200K deep water lighting 3 Maximum Power 15Watt 4 Maximum light intensity 1500Lumens 5 Control method PWM / switching direct control 6 PWM signal range 3～48V

[0073] In some embodiments, in order to solve the problem of insufficient sampling volume and inability to continuously sample for a long time in the interstitial water in-situ collection technology, the specific structure of the interstitial water sampler is designed to achieve continuous collection of interstitial water, such as Figures 2 to 4As shown, the interstitial water sampler 310 includes an interstitial water enrichment unit 3110, a pumping unit 3120 and a sample collection unit 3130; the interstitial water enrichment unit 3110 is connected to the sample collection unit 3130 through the pumping unit 3120; the interstitial water enrichment unit 3110 includes an outer layer seepage 3111, an inner layer seepage 3112, an interstitial water tank 3113 and a first water conduit 3114; wherein, the outer layer seepage 3111, the inner layer seepage 3112 and the interstitial water tank 3113 are connected in sequence from the outside to the inside, one end of the first water conduit 3114 is connected to the interstitial water tank 3113, and the other end is connected to the pumping unit 3120.

[0074] In this embodiment, the interstitial water sampler 310 has the characteristics of flexible deployment, simple operation, long working duration, and high collection efficiency, and is suitable for continuous automatic sampling of interstitial water in soil, river and lake sediments.

[0075] The purpose of the interstitial water enrichment unit 3110 is to increase the interstitial water catchment area and collect the interstitial water in the monitoring site. The interstitial water in the monitoring site will enter the interstitial water tank 3113 through the osmosis of the outer layer osmosis 3111 and the inner layer osmosis 3112, and then be collected and discharged by the first water pipe 3114.

[0076] Exemplarily, the outer layer permeation 3111 and the inner layer permeation 3112 are mesh structures, respectively filled with first gravel and second gravel; wherein the particle size of the first gravel is larger than the particle size of the second gravel. The interstitial water tank 3113 is annular, and a watertight bottom cover 3115 is provided at the bottom of the interstitial water tank 3113, and a top cover with a water outlet joint is provided at the top of the interstitial water tank 3113, and the water outlet joint is connected to the first water conduit 3114.

[0077] The outer layer infiltration 3111 and the inner layer infiltration 3112 are mesh structures, filled with gravels of larger and smaller particle sizes respectively, to ensure smooth flow of interstitial water. The interstitial water tank 3113 is annular, with a watertight bottom cover 3115 and a top cover with a water outlet joint on the top, and dense small holes can be arranged in the center of the side wall of the interstitial water tank 3113, and covered with gauze to filter impurities from the interstitial water entering the interstitial water tank to the maximum extent. A coarse filtering device can also be installed at the bottom of the first water conduit 3114 to keep the interstitial water clean and ensure smooth flow.

[0078] The pumping unit 3120 is connected to the interstitial water enrichment unit 3110 and is generally arranged on the surface of the monitoring site. Its main purpose is to pump out the interstitial water collected in the interstitial water tank 3113 and transport it to the sample collection unit 3130 under pressure.

[0079] In some embodiments, the pumping unit 3120 includes a second water pipe 31201, an electromagnetic three-way valve 31202, a syringe barrel 31203, a syringe piston 31204, a lower plate 31205, a middle plate 31206, an upper plate 31207, a support shaft 31208 and an electric telescopic rod 31209; the electromagnetic three-way valve 31202 has three ports, namely a first port a, a second port b and a third port c, one end of the second water pipe 31201 is connected to the third port c, the other end of the second water pipe 31201 is connected to the first water pipe 3114, and the second port b is connected to the sample collection unit 31204. 130, the first port a pipeline is connected to the liquid end of the syringe barrel 31203; at least one support shaft 31208 is set between the lower plate 31205 and the middle plate 31206, the syringe barrel 31203 is fixedly clamped by the lower plate 31205 and the middle plate 31206, the syringe piston 31204 is set in the syringe barrel 31203, the syringe piston 31204 is connected to the piston rod 31210, one end of the piston rod 31210 is fixed to the lower end of the upper plate 31207, the electric telescopic rod 31209 is fixed to the upper plate 31207, and the telescopic end of the electric telescopic rod 31209 is connected to the middle plate 31206.

[0080] The suction principle of the pumping unit 3120 is similar to that of the syringe. The upper plate 31207 is fixed, and the fixing method includes but is not limited to the use of an external bracket. First, the electromagnetic three-way valve 31202 is adjusted so that the second water conduit 31201 is connected to the liquid end of the syringe barrel 31203. At this time, the middle plate 31206 is pushed upward by adjusting the electric telescopic rod 31209. At this time, the piston rod 31210 will also move upward, and the syringe piston 31204 moves upward to suck out the interstitial water in the interstitial water enrichment unit 3110. Then adjust the electromagnetic three-way valve 31202 so that the liquid end of the syringe barrel 31203 is connected to the sample collection unit 3130, control and adjust the electric telescopic rod 31209 to push the middle plate 31206 to move downward, push the syringe piston 31204 downward, and discharge the interstitial water sucked into the syringe barrel 31203 by the previous operation to the sample collection unit 3130.

[0081] In a specific embodiment, three metal support shafts are sleeved between the middle plate 31206 and the upper plate 31207. The lower plate with screw holes is installed at the lower part of the syringe barrel 31203; the middle plate 31206 is composed of two identical plates with screw holes, which are clamped on the upper and lower parts of the baffle of the syringe barrel 31203; the upper plate 31207 has a piston block 31211, and a hand-tightened blind nut 31214 is installed on the upper part to fix the piston rod 31210. The two ends of the electric telescopic rod 31209 are fixed between the middle plate 31206 and the upper plate 31207 by nuts, and are controlled by electric equipment.

[0082] In a specific embodiment, the pumping unit 3120 also includes an electromagnetic switch 31212 and an electric control switch 31213 . The electromagnetic switch 31212 is communicatively connected to the electromagnetic three-way valve 31202 ; the electric control switch 31213 is communicatively connected to the electric telescopic rod 31209 .

[0083] The sample collection unit 3130 is mainly used to filter and collect interstitial water samples. For example, the sample collection unit may include a water pipe and a needle filter interface. The water pipe is made of hard plastic, and the needle filter interface adopts a standard interface specification.

[0084] In an exemplary embodiment, considering the use frequency of the sensor element, combined with the low power consumption, low voltage, and medium transmission distance of the device, an AC online power supply mode is selected, and different components DC / DC and DC / AC conversion modules are used to supply the normal operation of the equipment and the underwater lithium iron phosphate battery power supply. The underwater power supply can work continuously for 120 days at a monitoring frequency of 1h / time. The power specifications of each component are shown in Table 6.

[0085] Table 6 Statistics of power consumption specifications of each power unit of the device

[0086] Serial number Power unit name Voltage (V) Power(W) Operating frequency 1 Microcontroller 12 15 Normally Open 2 Mud level meter 12 10 Normally Open 3 Dissolved oxygen meter 24 10 Normally Open 4 Temperature and conductivity meter 12 10 Normally Open 5 Underwater Lights 24 25 Normally unloaded, working when the PTZ is working 6 Underwater PTZ Camera 24 30 Normally unloaded, working when the PTZ is working 7 Interstitial water collector 24 20 Normally unloaded, working during sample collection

[0087] When the sensor element works underwater, it may not only be physically damaged by water flow impact, sediment wear or destruction of underwater organisms, but also may be affected by temperature and salinity changes. Considering the communication distance and equipment maintainability, you can choose optical fiber transmission or twisted pair data transmission scheme. This embodiment uses twisted pair (RVVSP, 13-core Gigabit Ethernet cable) to transmit electricity and data. The Fathom-X cable interface, ttl to 232 board, and ttl to network port are combined as a communication module. The Fathom-X parameters are shown in Table 7:

[0088] Table 7 Fathom-X cable interface board detailed parameters

[0089] Serial number parameter Specification 1 Supply voltage 7-28V 2 Maximum Power 2.5Watts 3 Communication bandwidth 100Mbps 4 Maximum communication distance 350m

[0090] In some embodiments, a master-slave network control architecture is used between the underwater auxiliary control unit 200 and the host control unit 100. The underwater auxiliary control unit 200 can independently control the acquisition unit to work and record data, and can also serve as an auxiliary structure of the host control unit 100 to control the acquisition unit to complete data or sample acquisition. The host control unit 200 can provide the following functions through the configuration software: Figure 5): ① Real-time feedback of temperature, conductivity, dissolved oxygen, and mud level information measured by the sensor element; ② Setting the working frequency of the acquisition unit; ③ Controlling the start and reset of the acquisition unit; ④ Controlling the switch of the PTZ camera and underwater light; ⑤ Real-time feedback of the PTZ camera image; ⑥ Real-time feedback of the communication connection status of the sensor element, the power consumption of the underwater part of the equipment, water leakage and other safety status; ⑦ Reading and copying the data of the underwater auxiliary control unit; ⑧ Abnormal value inspection and data cleaning.

[0091] In some embodiments, the device can be assembled and deployed through the following steps:

[0092] Step 1. Assemble the controller, power supply module, and communication module according to the hardware structure of the underwater auxiliary control unit, and connect the corresponding watertight interfaces. Manually turn on the controller switch to check whether its working indicator light is on normally. After confirming that the controller is working normally, gently place the underwater auxiliary control unit module in the pressure-resistant sealed cabin and seal it. Use a vacuum extraction device to extract the pressure-resistant sealed cabin to a vacuum state and test its vacuum degree. After standing for 24 hours, if the vacuum degree remains unchanged, it is considered that the pressure-resistant sealed cabin is completely sealed.

[0093] Step 2: Fix the components of the acquisition unit on the fixed bracket, and connect the circuit and data watertight connection line between the acquisition unit and the underwater auxiliary control unit. In addition, connect the host control unit and the underwater auxiliary control unit through a watertight umbilical cable. Use the host computer to monitor the equipment circuit and signal path. If the indicator light is on normally, the equipment can work normally.

[0094] Step 3: Set up the acquisition unit at the selected monitoring point and insert each sensor element at the target monitoring position. The underwater auxiliary control unit is set within 5m of the acquisition unit and reinforced with a fixed bracket in the field. Turn on the host computer and click Start, and the device will start to work normally.

[0095] An embodiment of the present invention also provides a method suitable for continuous monitoring of dynamic changes of deep-water sediments and key environmental indicators in riverbank zones. The method is based on the device provided in any of the above embodiments and includes the following steps S1 to S3, which are described in detail as follows.

[0096] S1. Determine the sediment deposition thickness and sediment scouring thickness of the monitoring area based on the flow velocity, water depth, water body width, sediment content, sediment starting velocity and sediment density of the monitoring area.

[0097] In some embodiments, according to the flow velocity, water depth, water body width, sediment content, sediment starting velocity and sediment density of the monitoring area, the sediment deposition thickness and sediment scouring thickness of the monitoring area are determined by the following formula:

[0098]

[0099] In the formula, H沉 represents the thickness of sediment deposition, C s represents the sediment content of the water body, v represents the average flow velocity of the river, B represents the width of the water body, h p represents water depth, T represents equipment placement time, ρ represents sediment density, A represents bottom area, H 冲 Indicates the thickness of sediment scour.

[0100] S2. Determine the installation method of the underwater auxiliary unit and the collection unit in the device described in any of the above embodiments according to the sediment deposition thickness and the sediment scouring thickness, and install the underwater auxiliary unit and the collection unit underwater in the determined installation method;

[0101] In some embodiments, a series of hydrological change conditions (Table 8) with constant integral over time are proposed for calculating and analyzing the thickness of sediment deposition / scouring, and on this basis, the equipment deployment conditions and positions are determined. The suitability of equipment deployment is determined based on the estimated sediment deposition / scouring, wherein the equipment deployment suitability is in a suitable state, and the equipment can be simply fixed on site to ensure long-term stable operation; when the equipment deployment suitability is in a relatively suitable state, the underwater auxiliary unit and the collection unit need to be equipped with a fixed bracket, or the underwater auxiliary unit and the umbilical cable of the equipment need to be buried 10 cm below the sediment; when the equipment deployment suitability is in an unsuitable state, the monitoring point needs to be replaced or, in addition to installing a fixed bracket, the underwater auxiliary unit and the collection unit need to be equipped with a counterweight.

[0102] Table 8 Detailed parameters of high resolution temperature sensor element

[0103]

[0104] As shown in Table 8, in this embodiment, the installation mode of the underwater auxiliary unit and the acquisition unit can be determined by the following method:

[0105] If the thickness of sediment deposition is 0-20cm or the thickness of sediment scour is 0-3cm, the installation method is to directly install the underwater auxiliary unit and the collection unit underwater; if the thickness of sediment deposition is 20-50cm or the thickness of sediment scour is 3-8cm, the installation method is to install a fixed bracket underwater or to place the watertight umbilical cable below 10cm below the sediment to install the underwater auxiliary unit and the collection unit; if the thickness of sediment deposition is greater than 50cm or the thickness of sediment scour is greater than 8cm, other monitoring points need to be selected, or the installation method is to install the underwater auxiliary unit and the collection unit underwater by adding counterweights and installing fixed brackets.

[0106] S3. A host computer control unit is deployed in the onshore area of ​​the riverbank, and a watertight umbilical cable is used between the host computer control unit and the underwater auxiliary unit to complete electrical and signal transmission; the host computer control unit is used to display the working status of the collection unit, the data monitored by the collection unit, and control the collection unit in real time.

[0107] The following will illustrate with examples.

[0108] In this example, the Three Gorges Reservoir is selected as the research area. The Three Gorges Reservoir implements the "winter storage and summer discharge" off-season regulation mode, forming a riverbank with a drop of 30m in the reservoir area. Pengxi River is an important secondary river in the middle section of the Three Gorges Reservoir area, with a drainage area of ​​about 48km 2 , accounting for about 16% of the total area of ​​the drawdown zone in the reservoir area. This area concentrates the geographical characteristics and climate and meteorological characteristics of most of the basins in the middle and western sections of the Three Gorges Reservoir area, and is typical and representative in the study of riparian zones. The proposed site for this experiment is located at N31°5'48", E108°40'20", with a slope of less than 45° in the area, and the land use type is mainly grassland, and is less affected by external influences such as upstream or mainstream backflow ( Figure 6 ).

[0109] According to the survey, the average flow rate of the river in this area is 0.05m / s, the sediment starting flow rate is 0.5m / s, the water depth is 15m, and the sand content in the water is 500mg / m 3 , sediment density 14000kg / m 3 The deployment time is 2 days. According to calculations, the sediment thickness in this area is less than 20 cm within 2 days, which is very suitable for the deployment of the monitoring equipment.

[0110] Assemble the hardware structure of the underwater auxiliary control unit, including the controller, power supply module, communication module, and connect the corresponding circuits and data paths ( Figure 7 A). Turn on the controller manually to check whether its working indicator light is on normally. After confirming that the controller is working normally, gently place the underwater auxiliary control unit module in the pressure-resistant sealed cabin and seal it. Use a vacuum extraction device to extract the pressure-resistant sealed cabin to a vacuum degree of more than 95%, let it stand for 24 hours, and if the vacuum degree remains unchanged, it is considered that the pressure-resistant sealed cabin is completely sealed.

[0111] Fix the components of the acquisition unit on the fixed bracket, and connect the circuit and data watertight connection line between the acquisition unit and the underwater auxiliary control unit ( Figure 7 In addition, the upper computer control unit is connected to the underwater auxiliary control unit through a watertight umbilical cable. The upper computer is used to monitor the equipment circuit and signal path. If the indicator light is on normally, the equipment is working normally.

[0112] At the selected monitoring point in the water level fluctuation area, the underwater auxiliary unit and the collection unit are deployed using a fixed bracket during the water level drop period, and the sensor element of the collection unit is buried in the sediment ( Figure 7 (C) The host control unit is located near the shore.

[0113] Use the host computer control unit software to set the acquisition unit, set the working frequency to 1 minute / time, and control the underwater auxiliary control unit and acquisition unit to start working, so as to realize continuous monitoring of key environmental indicators of the riverbank zone / sediment and interstitial water collection.

[0114] During the two-day monitoring of the Three Gorges riverbank, a series of data on the changes in sediment temperature, conductivity, dissolved oxygen content, and sediment thickness in the riverbank zone over time were obtained under water level fluctuations. The results are as follows: Figure 8 , indicating that the present invention realizes the continuous monitoring of sediment dynamic changes and key environmental indicators, and obtains high-frequency, high-precision batch data.

[0115] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that the technical solutions described in the above embodiments may still be modified, or some or all of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention, and should all be included in the scope of the claims and specification of the present invention.

Claims

1. A device suitable for continuous monitoring of dynamic changes of deep-water sediments and key environmental indicators in riverbanks, characterized in that: The device comprises a host computer control unit, an underwater auxiliary unit and a collection unit; The underwater auxiliary unit and the acquisition unit are arranged underwater, the underwater auxiliary unit is connected to the host computer control unit by signal, so as to receive the control instruction issued by the host computer control unit, the underwater auxiliary unit is connected to the acquisition unit by signal, so as to control the acquisition unit to work and receive the data transmitted by the acquisition unit according to the embedded development control instruction and the host computer control unit control instruction, and the acquisition unit includes a voltage detection element, a current detection element, a water leakage detection element, a pan-tilt camera, an underwater light, a temperature sensor element, a conductivity sensor element, a dissolved oxygen sensor element, a mud level meter and a gap water sampler; The host computer control unit is used to receive and display the data transmitted by the acquisition unit.

2. The device according to claim 1, characterized in that The interstitial water sampler comprises an interstitial water enrichment unit, a water pumping unit and a sample collection unit; The interstitial water enrichment unit is connected to the sample collection unit via the pumping unit; The interstitial water enrichment unit includes an outer layer infiltration, an inner layer infiltration, an interstitial water tank and a first water pipe; wherein the outer layer infiltration, the inner layer infiltration and the interstitial water tank are connected in sequence from the outside to the inside, one end of the first water pipe is connected to the interstitial water tank, and the other end is connected to the pumping unit.

3. The device according to claim 2, characterized in that The pumping unit includes a second water conduit, an electromagnetic three-way valve, a syringe barrel, a syringe piston, a lower plate, a middle plate, an upper plate, a support shaft and an electric telescopic rod; the electromagnetic three-way valve has three ports, namely a first port, a second port and a third port, one end of the second water conduit is connected to the third port, the other end of the second water conduit is connected to the first water conduit, the second port is connected to the sample collection unit, and the first port pipeline is connected to the liquid end of the syringe barrel; at least one support shaft is arranged between the lower plate and the middle plate, the syringe barrel is fixedly clamped by the lower plate and the middle plate, the syringe piston is arranged in the syringe barrel, the syringe piston is connected to the piston rod, one end of the piston rod is fixed to the lower end of the upper plate, the electric telescopic rod is fixed to the upper plate, and the telescopic end of the electric telescopic rod is connected to the middle plate.

4. The device according to claim 3, characterized in that A piston block is arranged on the upper plate, and the piston rod is arranged in the piston block and fixed by a nut.

5. The device according to claim 3, characterized in that The pumping unit further comprises an electromagnetic switch, which is communicatively connected with the electromagnetic three-way valve; the pumping unit further comprises an electric control switch, which is communicatively connected with the electric telescopic rod.

6. The device according to claim 3, characterized in that The outer layer permeation and the inner layer permeation are mesh structures, and are filled with first gravel and second gravel respectively; wherein the particle size of the first gravel is larger than the particle size of the second gravel.

7. The device according to claim 3, characterized in that The interstitial water tank is annular, a watertight bottom cover is provided at the bottom of the interstitial water tank, a top cover with a water outlet joint is provided at the top of the interstitial water tank, and the water outlet joint is connected to the first water conduit.

8. A method for continuous monitoring of dynamic changes in deepwater sediments and key environmental indicators in riverbanks, characterized in that: Based on the device according to any one of claims 1 to 7, the method comprises: Determine the sediment deposition thickness and sediment scouring thickness of the monitoring area based on the flow velocity, water depth, water body width, sediment content, sediment starting velocity and sediment density of the monitoring area; Determine the installation method of the underwater auxiliary unit and the collection unit in the device according to any one of claims 1 to 7 according to the sediment deposition thickness and the sediment scouring thickness, and install the underwater auxiliary unit and the collection unit underwater according to the determined installation method; A host computer control unit is arranged in the onshore area of ​​the riverbank, and a watertight umbilical cable is used between the host computer control unit and the underwater auxiliary unit to complete electrical and signal transmission; the host computer control unit displays the working status of the collection unit, the data monitored by the collection unit, and controls the collection unit in real time.

9. The method according to claim 8, characterized in that According to the flow velocity, water depth, water body width, sediment content, sediment starting velocity and sediment density of the monitoring area, the sediment deposition thickness and sediment scouring thickness of the monitoring area are determined by the following formula: In the formula, H 沉 represents the thickness of sediment deposition, C s represents the sediment content of the water body, v represents the average flow velocity of the river, B represents the width of the water body, h p represents water depth, T represents equipment placement time, j represents sediment density, A represents bottom area, H represents 冲 Indicates the thickness of sediment scour.

10. The method according to claim 8, characterized in that The installation method of the underwater auxiliary unit and the acquisition unit is determined by the following method: If the sediment thickness is 0-20cm or the sediment scour thickness is 0-3cm, the installation method is to directly install the underwater auxiliary unit and the collection unit underwater; If the thickness of sediment deposition is 20-50cm or the thickness of sediment scour is 3-8cm, the installation method is to install a fixed bracket underwater or insert the watertight umbilical cable below 10cm below the sediment to install the underwater auxiliary unit and the acquisition unit; If the sediment thickness is greater than 50 cm or the sediment scour thickness is greater than 8 cm, select an alternative monitoring point, or install the underwater auxiliary unit and collection unit underwater by adding counterweights and installing fixed brackets.

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