Apparatus and methods for continuous monitoring of dynamic changes in deep-water sediments and key environmental indicators in riparian zones

Abstract

This invention belongs to the field of environmental monitoring technology, specifically disclosing a device and method for continuous monitoring of dynamic changes and key environmental indicators of deep-water sediments in riparian zones. The device includes a host computer control unit, an underwater auxiliary unit, and a data acquisition unit. The underwater auxiliary unit and the data acquisition unit are located underwater. The underwater auxiliary unit is signal-connected to the host computer control unit to receive control commands from the host computer control unit. The underwater auxiliary unit is also signal-connected to the data acquisition unit to control the operation of the data acquisition unit and receive data transmitted by the data acquisition unit according to the control commands from the underwater auxiliary unit and the host computer control unit. The host computer control unit receives and displays the data transmitted by the data acquisition unit. This invention enables high-precision, high-frequency monitoring and batch data acquisition of key environmental indicators and interstitial water in deep-water sediments.

Description

Technical Field

[0001] This invention relates to the field of environmental monitoring technology, and in particular to an apparatus and method suitable for continuous monitoring of dynamic changes in deep-water sediments and key environmental indicators in riparian zones. Background Technology

[0002] Sediments are crucial sites for the enrichment and transformation of biogenic elements in lakes and reservoirs. They are highly sensitive to environmental changes yet remain stable, reflecting the biogeochemical cycles and environmental evolution processes of lakes and reservoirs. Therefore, accurately obtaining dynamic data on sediments and continuous changes in key environmental indicators is of great significance for studying environmental changes and material behavior in lakes and reservoirs.

[0003] Currently, sediment monitoring employs either a pre-collection followed by laboratory analysis approach or point-based continuous monitoring using single-index sensors. Regular surveys remain a widely used method for sediment monitoring, utilizing in-situ collection devices such as sediment collectors, thin-film gradient diffusion gradient technology, and underwater sampling robots. This method requires regular, large-scale on-site investigations, proper preservation and transportation of samples, and timely return to the laboratory for analysis. This often results in high sediment sample acquisition costs, low acquisition frequency, and significant sample interference during processing. Furthermore, laboratory testing can easily distort sediment environmental indicators. Environmental sensors, through optical, electrical, acoustic, and chemical signals, reflect corresponding environmental parameters, providing continuous, high-precision, in-situ monitoring data of the monitored medium. Currently, environmental sensors are widely used in sediment monitoring. For example, the Sequoia LISST sensor uses laser diffraction technology to measure sediment particle size distribution and concentration; the Aanderaa Optode 4835 sensor monitors dissolved oxygen content in marine and freshwater sediments based on the principle of optical fluorescence quenching. However, the differences in the working principles and transmission signals of various sensing elements make it difficult to integrate and intelligently manage sediment environmental monitoring indicators. Furthermore, existing sediment sensors typically send monitoring commands and receive and record data signals via handheld terminals, resulting in low data acquisition efficiency. Moreover, during deep-water monitoring, the long data transmission times easily lead to data loss or distortion, hindering sediment monitoring and research.

[0004] Therefore, existing sediment monitoring equipment suffers from problems such as low data acquisition efficiency, distortion of data from ex-situ samples, susceptibility to contamination during sample processing, and signal loss or distortion due to long-distance data transmission, making it difficult to meet the current research needs of sediments. This invention addresses the shortcomings of current sediment monitoring methods and devices by proposing an integrated automated device with a master-slave network control structure, coordinating multiple sensing elements to work simultaneously, and achieving interstitial water collection. This is of great significance for environmental monitoring and biochemical process research of riparian / deep-water sediments. Summary of the Invention

[0005] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide an apparatus and method for continuous monitoring of dynamic changes and key environmental indicators of riparian deep-water sediments, so as to achieve high-precision, high-frequency monitoring and batch data acquisition of key environmental indicators of riparian / deep-water sediments.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] According to a first aspect of the present invention, an apparatus is provided for continuous monitoring of dynamic changes in deep-water sediments and key environmental indicators in riparian zones, the apparatus comprising a host computer control unit, an underwater auxiliary unit, and a data acquisition unit;

[0008] The underwater auxiliary unit and the acquisition unit are located underwater. The underwater auxiliary unit is signal-connected to the host computer control unit to receive control commands issued by the host computer control unit. The underwater auxiliary unit is signal-connected to the acquisition unit to control the acquisition unit to work according to the control commands and to receive data transmitted by the acquisition unit. The acquisition unit includes a voltage detection element, a current detection element, a leakage detection element, a pan-tilt camera, an underwater light, a temperature sensing element, a conductivity sensing element, a dissolved oxygen sensing element, a mud level gauge, and an interstitial 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 operate independently of the upper control unit to control the acquisition unit and record data.

[0011] Furthermore, the interstitial water sampler includes an interstitial water enrichment unit, a pumping 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 permeable layer, an inner permeable layer, an interstitial water tank, and a first water guide pipe; wherein the outer permeable layer, the inner permeable layer, and the interstitial water tank are connected sequentially from the outside to the inside, and one end of the first water guide 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 guide 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: a first port, a second port, and a third port. One end of the second water guide pipe is connected to the third port, and the other end of the second water guide pipe is connected to the first water guide pipe. The second port is connected to the sample collection unit, and the first port is connected to the liquid end of the syringe barrel. At least one support shaft is provided 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 disposed inside the syringe barrel and is connected to a 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 provided on the upper plate, and the piston rod is disposed 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 also includes an electric control switch, which is communicatively connected to the electric telescopic rod.

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

[0018] Furthermore, the gap water tank is annular, the bottom of the gap water tank is provided with a water-impermeable bottom cover, and the top of the gap water tank is provided with a top cover with a water outlet connector, the water outlet connector being connected to the first water guide pipe.

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

[0020] Based on the flow velocity, water depth, water body width, sediment content, sediment initiation velocity, and sediment density of the monitoring area, determine the sediment deposition thickness and sediment scour thickness of the monitoring area;

[0021] The installation method of the underwater auxiliary unit and the acquisition unit in the device described above is determined based on the thickness of sediment deposition and the thickness of sediment scour, and the underwater auxiliary unit and the acquisition unit are installed underwater according to the determined installation method.

[0022] A host computer control unit is deployed in the land area of ​​the riverbank. The host computer control unit and the underwater auxiliary unit are connected by a watertight umbilical cable to complete the electrical and signal transmission. The host computer control unit can display the working status of the acquisition unit, the data monitored by the acquisition unit, and control the acquisition unit in real time.

[0023] Furthermore, based on the flow velocity, water depth, water body width, sediment content, sediment initiation velocity, and sediment density of the monitoring area, the sediment deposition thickness and sediment scour thickness of the monitoring area are determined using the following formula:

[0024]

[0025] In the formula, H 沉 C represents the thickness of sediment deposition. s The water body contains sediment, v represents the average flow velocity of the river, B represents the width of the water body, and h represents the average flow velocity of the river. p The water depth is represented by T, the equipment installation time is represented by ρ, the sediment density is represented by A, and the bottom area is represented by H. 冲 This indicates the thickness of the silt erosion.

[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 scouring thickness is 0-3cm, the installation method is to directly install the underwater auxiliary unit and the data acquisition unit underwater.

[0028] If the sediment deposition thickness is 20-50cm and the sediment scouring thickness is 3-8cm, the installation method is to install the underwater auxiliary unit and the data acquisition unit by adding a fixed support underwater and inserting the watertight umbilical cable 10cm below the sediment.

[0029] If the sediment deposition thickness is greater than 50cm or the sediment erosion thickness is greater than cm, other suitable monitoring points should be selected, or counterweights should be added and fixed supports should be installed underwater to install underwater auxiliary units and data acquisition units.

[0030] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0031] 1. The device proposed in this invention can achieve high-precision, high-frequency monitoring and batch data acquisition of key environmental indicators and interstitial water in deep-water sediments. In particular, it can achieve automatic collection of interstitial water by setting up interstitial water enrichment units.

[0032] 2. The method proposed in this invention determines the installation method of underwater equipment based on the thickness of sediment deposition and sediment scouring, which can select effective monitoring points and improve the working stability and service life of underwater equipment at the lowest cost. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of the present invention or 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 only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

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

[0035] Figure 2 This is a schematic diagram of the structure of an interstitial water sampler according to an embodiment of the present invention.

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

[0037] Figure 4 This is a perspective view of the interstitial water enrichment unit in an interstitial water sampler according to an embodiment of the present invention.

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

[0039] Figure 6 This is a map of the experimental area of ​​the riverbank zone of the Three Gorges Reservoir according to an embodiment of the present invention.

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

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

[0042] Figure label:

[0043] 100. Host computer control unit;

[0044] 200. Underwater auxiliary unit; 201. Underwater controller; 202. Underwater power supply;

[0045] 300. Acquisition unit; 301. Voltage detection element; 302. Current detection element; 303. Leakage detection element; 304. Pan-tilt camera; 305. Underwater light; 306. Temperature sensing element; 307. Conductivity sensing element; 308. Dissolved oxygen sensing element; 309. Mud level gauge;

[0046] 310. Interstitial water sampler; 3110. Interstitial water enrichment unit; 3111. Outer layer permeation; 3112. Inner layer permeation; 3113. Interstitial water tank; 3114. First water guide pipe; 3115. Impermeable bottom cover; 3120. Pumping unit; 31201. Second water guide pipe; 31202. Electromagnetic 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 catch; 31212. Electromagnetic switch; 31213. Electric control switch; 31214. Hand-tightened end cap nut; 3130. Sample collection unit. Detailed Implementation

[0047] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, unless otherwise specified, the following embodiments and features described therein can be combined with each other.

[0048] In the description of this invention, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," "tail," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying their relative importance.

[0049] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

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

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

[0052] The underwater auxiliary unit 200 and the acquisition unit 300 are located underwater. The underwater auxiliary unit 200 is signal-connected to the host computer control unit 100 to receive control commands issued by the host computer control unit 100. The underwater auxiliary unit 200 is signal-connected to the acquisition unit 300 to control the acquisition unit 300 to work according to the control commands and to receive the data transmitted by the acquisition unit 300. The acquisition unit 300 includes a voltage detection element 301, a current detection element 302, a leakage detection element 303, a pan-tilt camera 304, an underwater light 305, a temperature sensing element 306, a conductivity sensing element 307, a dissolved oxygen sensing element 308, a mud level gauge 309, and an interstitial water sampler 310. The host computer control unit 100 is used to receive and display the data transmitted by the acquisition unit 300.

[0053] In this embodiment, the host computer control unit 100 is responsible for collecting the operator's control commands, including setting the operating frequency of the sensing element, executing the operation of the interstitial water collector 310, and switching on / off the pan-tilt camera 304 and the underwater light 305. These commands are sent to the underwater environment via Ethernet through the interface board and umbilical cable. At the same time, the host computer control unit 100 receives data transmitted by the underwater auxiliary unit 200 and displays it on the monitoring interface.

[0054] For example, a communication module is configured in the host computer control unit 100 and the underwater auxiliary unit 200 respectively. The two communication modules are connected by an umbilical cable to establish a communication connection, thereby enabling information interaction between the host computer control unit 100 and the underwater auxiliary unit 200.

[0055] The underwater auxiliary unit 200 can be implemented as an auxiliary computer, for example. During underwater assembly of the underwater auxiliary unit 200 and the data acquisition unit 300, watertight devices are installed to ensure that the internal components remain dry during underwater operation. The underwater auxiliary unit 200 may include an underwater controller 201 and an underwater power supply 202, employing a single controller structure with a power storage / supply system and communication module. Its task is to control the data acquisition unit (mud level gauge 309, interstitial water collector 310, pan-tilt camera 304, dissolved oxygen sensor 308, underwater light 305, voltage detection element 301, current detection element 302, leakage detection element 303, etc.) according to control commands, read and store sensor data, and communicate with the host computer control unit 100 via Ethernet. During deployment, the distance between the data acquisition unit 300 and the underwater auxiliary control unit 200 is less than 5 meters to ensure monitoring frequency and data transmission fidelity.

[0056] Exemplarily, the circuitry and data interfaces of the umbilical cable and sensing elements all utilize custom-designed watertight connectors to ensure a watertight connection when connected to the underwater auxiliary unit 200. The underwater auxiliary unit 200 is housed entirely within a pressure-resistant, sealed chamber equipped with watertight connectors, maintaining a dry environment during underwater operation. The watertight device is designed to operate normally at a depth of 100 meters. The watertight device is an existing structural component capable of achieving a watertight seal; its specific structure is not limited in this embodiment.

[0057] Underwater equipment is susceptible to damage from water pressure and sediment disturbance during operation, especially optical and acoustic sensing elements. Therefore, the sensing elements in the data acquisition unit should ideally be based on electrical principles, and a watertight design should be incorporated to ensure they can withstand high-pressure environments. To ensure consistency of current, voltage, and data signals between the underwater auxiliary control unit, the data acquisition unit, and the host computer control unit, appropriate DC / DC and DC / AC power supply modules and communication modules are required. The main hardware parameters are as follows:

[0058] 1) Temperature and conductivity sensing elements (i.e., temperature sensing element 306 and conductivity sensing element 307). Temperature and conductivity sensing elements based on the FDR (Frequency Domain Reflectometry) principle are selected. They have good anti-electromagnetic interference capabilities, 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 30 seconds, allowing for long-term continuous operation, meeting the high-frequency, high-precision, and long-term continuous sediment monitoring requirements of this equipment. Its specifications are shown in Tables 1 and 2.

[0059] Table 1 Detailed parameters of high-resolution temperature sensing elements

[0060] Serial Number parameter Specification 1 range -20～80℃ 2 accuracy 0.1℃ 3 Communication methods ModBusRTU protocol

[0061] Table 2 Detailed parameters of high-resolution conductivity sensing elements

[0062] Serial Number parameter Specification 1 range 0~2000us / cm 2 accuracy 1us / cm 3 Communication methods ModBusRTU protocol

[0063] 2) Dissolved oxygen sensing element 308. A temperature-corrected thermistor sensing element is selected to measure the dissolved oxygen content in the sediment. This element has a maximum data reading interval of 14 seconds and can perform long-term continuous monitoring. Its specifications are shown in Table 3.

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

[0065] Serial Number parameter Specification 1 range 0～100％ 2 accuracy 0.1％ 3 Communication methods SDI-12 Protocol

[0066] 3) Mud level gauge 309. A mud level sensor based on digital signal processing technology and underwater ultrasonic echo algorithm is selected to monitor the changes in mud and sand thickness in the study area in real time. When measuring the changes in mud and sand thickness, the ultrasonic sensor is placed at a certain position on the bottom or underwater in either the forward or reverse direction. The change in mud and sand thickness is calculated by using the fixed speed of sound in water and the time from the emission to the reception of the ultrasonic wave. The maximum data reading interval of this element is 1 second, 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 gauge

[0068] Serial Number parameter Specification 1 range 0.015～6m 2 accuracy ±2mm 3 Communication methods ModBusRTU protocol

[0069] 4) Pan-Tilt Camera 304. The pan-tilt camera 304, installed underwater, is a key device for observing underwater vegetation, sediment dynamics, and equipment operation. It utilizes a low-light, high-definition Sony IMX322 sensor, employing a large sensor size (1 / 2.9″) and a relatively low pixel count (2MP, 1080p), providing excellent low-light performance, color processing capabilities, and onboard video compression capabilities without placing excessive burden on the control unit.

[0070] 5) Underwater Light 305. When the equipment is operating underwater, the surrounding light is relatively dim. At this time, the camera needs to use an underwater light to compensate for the lack of external light. The selection of the underwater light 305 should avoid noise in the video footage. The main specifications are shown in Table 5.

[0071] Table 5 Detailed parameters of underwater lighting

[0072] Serial Number parameter Specification 1 Power supply voltage 10～48V 2 Light color temperature 6200K Deep-sea Light 3 Maximum power 15Watt 4 Maximum light intensity 1500 Lumens 5 Control method PWM / Direct Switching 6 PWM signal range 3～48V

[0073] In some embodiments, to address the issues of insufficient sampling volume and inability to perform long-term continuous sampling in in-situ interstitial water sampling techniques, a specific structure for an interstitial water sampler was designed to achieve continuous interstitial water sampling, 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 permeable layer 3111, an inner permeable layer 3112, an interstitial water tank 3113, and a first water guide pipe 3114. The outer permeable layer 3111, the inner permeable layer 3112, and the interstitial water tank 3113 are connected sequentially from the outside to the inside. One end of the first water guide pipe 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 features flexible deployment, simple operation, long working duration, and high collection efficiency, making it suitable for continuous automatic sampling of interstitial water in soil and river / 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 infiltration of the outer layer infiltration 3111 and the inner layer infiltration 3112, and then be discharged through the first water guide pipe 3114.

[0076] For example, the outer permeable layer 3111 and the inner permeable layer 3112 are mesh structures, respectively filled with first gravel and second gravel; wherein the particle size of the first gravel is larger than that of the second gravel. The interstitial water tank 3113 is annular, with an impermeable bottom cover 3115 at the bottom and a top cover with a water outlet connector at the top, the water outlet connector being connected to the first water guide pipe 3114.

[0077] The outer permeable layer 3111 and the inner permeable layer 3112 have a mesh structure, filled with gravel of larger and smaller particle sizes respectively, to ensure smooth flow of interstitial water. The interstitial water chamber 3113 is annular, with an impermeable bottom cover 3115 and a top cover with a water outlet connector. Dense perforations can also be arranged in the center of the sidewall of the interstitial water chamber 3113, and covered with gauze to maximize the filtration of impurities in the interstitial water entering the chamber. A coarse filter can also be installed at the bottom of the first water guide pipe 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 installed 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 pressurize and transport it to the sample collection unit 3130.

[0079] In some embodiments, the pumping unit 3120 includes a second water guide 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 guide pipe 31201 is connected to the third port c, the other end of the second water guide pipe 31201 is connected to the first water guide pipe 3114, and the second port b is connected to the sample collection unit 3. 130, the first port a pipe is connected to the liquid end of the syringe barrel 31203; at least one support shaft 31208 is provided 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 provided inside 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 a syringe. The upper plate 31207 is fixed, and the fixing method includes, but is not limited to, using an external support. First, the electromagnetic three-way valve 31202 is adjusted to connect the second water guide tube 31201 with the liquid end of the syringe barrel 31203. At this time, the electric telescopic rod 31209 is adjusted to push the middle plate 31206 upward, causing the piston rod 31210 to move upward, and the syringe piston 31204 to move upward, thus drawing out the interstitial water from the interstitial water enrichment unit 3110. Then, the electromagnetic three-way valve 31202 is adjusted to connect the liquid end of the syringe barrel 31203 with the sample collection unit 3130. The electric telescopic rod 31209 is controlled to push the middle plate 31206 downward, pushing the syringe piston 31204 downward, thus discharging the interstitial water drawn into the syringe barrel 31203 in the previous operation to the sample collection unit 3130.

[0081] In one specific embodiment, three metal support shafts are fitted between the middle plate 31206 and the upper plate 31207. The lower plate with threaded holes is installed at the lower part of the syringe barrel 31203; the middle plate 31206 is composed of two identical plates with threaded holes, clamped between the upper and lower parts of the syringe barrel 31203 baffle; the upper plate 31207 has a built-in piston catch block 31211, and a hand-tightened blind nut 31214 is added to the upper part for fixing the piston rod 31210. The electric telescopic rod 31209 is fixed at both ends between the middle plate 31206 and the upper plate 31207 with nuts, and is controlled by an electric device.

[0082] In one specific embodiment, the pumping unit 3120 further 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 for filtering and collecting interstitial water samples. For example, the sample collection unit may include a water guide tube and a needle-type filter cartridge interface. The water guide tube is made of rigid plastic, and the needle-type filter cartridge interface adopts a standardized interface specification.

[0084] In one exemplary embodiment, considering the frequency of sensor usage and the device's low power consumption, low voltage, and medium transmission distance, an online AC power supply is selected, coupled with different DC / DC and DC / AC conversion modules to power the equipment for normal operation and the underwater lithium iron phosphate battery. The underwater power supply can operate continuously for 120 days at a monitoring frequency of 1 hour per cycle. The power specifications of each component are shown in Table 6.

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

[0086] Serial Number Electricity unit name Voltage (V) Power (W) Operating frequency 1 microcontroller 12 15 Normally open 2 Mud level gauge 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 idle, works when the gimbal is in operation 6 Underwater pan-tilt camera 24 30 Normally idle, works when the gimbal is in operation 7 Interstitial water collector 24 20 Normally unloaded, only works during sample collection.

[0087] When sensing elements operate underwater, they may suffer physical damage not only from water flow impact, sediment abrasion, or destruction by underwater organisms, but also from changes in temperature and salinity, which can affect signal transmission. Considering communication distance and equipment maintainability, fiber optic transmission or twisted-pair cable transmission can be selected. This embodiment uses a twisted-pair cable (RVVSP, 13-core gigabit Ethernet cable) transmission scheme for both electrical and data transmission. The communication module is composed of a Fathom-X cable interface, a TTL to RS-232 board, and a TTL to Ethernet port. Fathom-X parameters are shown in Table 7.

[0088] Table 7. Detailed Specifications of the Fathom-X Cable Interface Board

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

[0090] In some embodiments, a master-slave network control architecture is adopted between the underwater auxiliary control unit 200 and the host computer control unit 100. The underwater auxiliary control unit 200 can independently control the acquisition unit to work and record data, or it can act as an auxiliary structure of the host computer control unit 100 to operate the acquisition unit to complete data or sample acquisition. The host computer control unit 200 can provide the following functions through configuration software ( Figure 5The functions include: ① Real-time feedback of temperature, conductivity, dissolved oxygen, and mud level information measured by the sensors; ② Setting the operating frequency of the acquisition unit; ③ Controlling the start and reset of the acquisition unit; ④ Controlling the on / off of the PTZ camera and underwater lights; ⑤ Real-time feedback of PTZ camera images; ⑥ Real-time feedback of sensor communication connection status, underwater power consumption, water leakage, and other safety statuses; ⑦ Reading and copying data from the underwater auxiliary control unit; ⑧ Anomaly detection 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 them to the corresponding watertight interfaces. Manually turn on the controller switch and check if its indicator light illuminates normally. After confirming that the controller is working properly, gently place the underwater auxiliary control unit module into the pressure-resistant sealed chamber and seal it. Use a vacuum extraction device to evacuate the pressure-resistant sealed chamber to a vacuum state and check its vacuum level. After standing for 24 hours, if the vacuum level remains unchanged, the pressure-resistant sealed chamber is considered to be completely sealed.

[0093] Step 2: Secure all components of the acquisition unit to the mounting bracket, and connect the circuitry and watertight data cables between the acquisition unit and the underwater auxiliary control unit. Additionally, connect the host computer control unit to the underwater auxiliary control unit via a watertight umbilical cable. Use the host computer to monitor the equipment's circuitry and signal paths; if the indicator lights are illuminated normally, the equipment is functioning correctly.

[0094] Step 3: Deploy the data acquisition units at the selected monitoring points and insert each sensor element into the target monitoring location. The underwater auxiliary control unit should be deployed within 5 meters of the data acquisition units and secured with a reinforced support in the field. Turn on the host computer and click "Start" to begin normal operation of the equipment.

[0095] This invention also provides a method for continuous monitoring of dynamic changes in deep-water sediments and key environmental indicators in riparian zones. This method is based on the apparatus provided in any of the above embodiments and includes the following steps S1 to S3, which are described in detail below.

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

[0097] In some embodiments, the sediment deposition thickness and sediment scour thickness of the monitoring area are determined using the following formula, based on the flow velocity, water depth, water body width, sediment concentration, sediment initiation velocity, and sediment density of the monitoring area:

[0098]

[0099] In the formula, H沉 C represents the thickness of sediment deposition. s The water body contains sediment, v represents the average flow velocity of the river, B represents the width of the water body, and h represents the average flow velocity of the river. p The water depth is represented by T, the equipment installation time is represented by ρ, the sediment density is represented by A, and the bottom area is represented by H. 冲 This indicates the thickness of the silt erosion.

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

[0101] In some embodiments, a series of hydrological variation conditions with constant time integrals are proposed (Table 8) to calculate and analyze sediment deposition / scour thickness, and based on this, determine the equipment deployment conditions and location. The suitability of equipment deployment is determined based on the estimated sediment deposition / scour. A suitable deployment condition means the equipment can be easily fixed on-site to ensure long-term stable operation. A relatively suitable deployment condition requires the underwater auxiliary unit and acquisition unit to be fitted with fixed supports, or the underwater auxiliary unit and umbilical cable to be buried 10 cm below the sediment. An unsuitable deployment condition requires replacing the monitoring point or, in addition to adding fixed supports, adding weight to the underwater auxiliary unit and acquisition unit.

[0102] Table 8 Detailed parameters of high-resolution temperature sensing elements

[0103]

[0104] According to Table 8, the installation method of the underwater auxiliary unit and the acquisition unit can be determined in this embodiment using the following method:

[0105] If the sediment deposition thickness is 0-20cm or the sediment erosion thickness is 0-3cm, the installation method is to directly install the underwater auxiliary unit and the data acquisition unit underwater. If the sediment deposition thickness is 20-50cm or the sediment erosion thickness is 3-8cm, the installation method is to install the underwater auxiliary unit and the data acquisition unit by adding a fixed support underwater or by inserting the watertight umbilical cable at least 10cm below the sediment. If the sediment deposition thickness is greater than 50cm or the sediment erosion thickness is greater than 8cm, other monitoring points need to be selected, or the installation method is to add counterweights and a fixed support underwater to install the underwater auxiliary unit and the data acquisition unit.

[0106] S3. A host computer control unit is deployed in the land area of ​​the riverbank. The host computer control unit and the underwater auxiliary unit are connected by a watertight umbilical cable to complete the electrical and signal transmission. The host computer control unit displays the working status of the acquisition unit, the data monitored by the acquisition unit, and controls the acquisition unit in real time.

[0107] The following examples will illustrate this.

[0108] In this embodiment, the Three Gorges Reservoir was selected as the study area. The Three Gorges Reservoir operates on a counter-seasonal regulation model of "winter storage and summer discharge," creating a riverbank zone with a 30-meter drop in elevation within the reservoir area. The Pengxi River is an important secondary river in the middle section of the Three Gorges Reservoir area, with a drawdown zone area of ​​approximately 48 km². 2 This area, accounting for approximately 16% of the total drawdown zone of the reservoir area, concentrates the geographical features and climatic characteristics of most of the central and western sections of the Three Gorges Reservoir, making it typical and representative in riparian zone research. The proposed experimental site is located at N31°5'48" E108°40'20" , with a slope less than 45°, predominantly grassland, and minimal external influences such as upstream or main stream backflow. Figure 6 ).

[0109] According to the survey, the average river velocity in this area is 0.05 m / s, the sediment initiation velocity is 0.5 m / s, the water depth is 15 m, and the sediment concentration is 500 mg / m³. 3 The density of the silt is 14000 kg / m³ 3 The deployment time was 2 days. According to calculations, the sediment deposition thickness in this area within 2 days was less than 20 cm, making it very suitable for deploying the monitoring equipment.

[0110] Assemble the hardware structure of the underwater auxiliary control unit, including the controller, power supply module, and communication module, and connect the corresponding circuits and data paths. Figure 7 (A) Manually turn on the controller switch and check if its indicator light illuminates normally. After confirming that the controller is working properly, gently place the underwater auxiliary control unit module into the pressure-resistant sealed chamber and seal it. Use a vacuum extraction device to evacuate the pressure-resistant sealed chamber to a vacuum level of over 95%, and let it stand for 24 hours. If the vacuum level remains unchanged, the pressure-resistant sealed chamber is considered to be completely sealed.

[0111] Fix each component of the acquisition unit onto the fixed bracket, and connect the circuit and watertight data connection lines between the acquisition unit and the underwater auxiliary control unit. Figure 7 (B) In addition, the host computer control unit and the underwater auxiliary control unit are connected via a watertight umbilical cable. The host computer monitors the equipment circuitry and signal paths; if the indicator lights are on normally, the equipment is working properly.

[0112] At selected monitoring points in the water level fluctuation area, underwater auxiliary units and data acquisition units are deployed using fixed supports during periods of water level decline. The sensing elements of the data acquisition units are embedded in the sediment. Figure 7 (C). The host computer control unit is located near the shore.

[0113] The host computer control unit software is used to set the acquisition unit, and the working frequency is set to 1 minute / time. The underwater auxiliary control unit and acquisition unit are then operated to start working, so as to realize continuous monitoring of key environmental indicators of the riparian zone / sediments and interstitial water collection.

[0114] During a two-day monitoring period along the Three Gorges riverbank, a series of data were obtained on the time-series changes in sediment temperature, electrical conductivity, dissolved oxygen content, and sediment deposition thickness under fluctuating water levels. The results are as follows: Figure 8 This indicates that the present invention has achieved continuous monitoring of sediment dynamics and key environmental indicators, and has acquired high-frequency, high-precision batch data.

[0115] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention.

Claims

1. A method suitable for continuous monitoring of dynamic changes in deepwater sediments and key environmental indicators in riparian zones, characterized in that, The application discloses a device suitable for dynamic change of deep water sediments in a riparian zone and continuous monitoring of key environmental indexes, and the device comprises an upper computer control unit, an underwater auxiliary unit and a collecting unit. The underwater auxiliary unit and the collecting unit are arranged underwater, the underwater auxiliary unit is in signal connection with the upper computer control unit to receive control instructions sent by the upper computer control unit, and the underwater auxiliary unit is in signal connection with the collecting unit to control the collecting unit to work and receive data transmitted by the collecting unit according to embedded development control instructions and upper computer control unit control instructions. The upper computer control unit is used for receiving data transmitted by the collecting unit and displaying. The method comprises: According to the flow rate, water depth, water width, sediment concentration, sediment starting flow rate and sediment density of the monitoring area, the sediment deposition thickness and the sediment scouring thickness of the monitoring area are determined. According to the sediment deposition thickness and the sediment scouring thickness, the installation mode of the underwater auxiliary unit and the collecting unit in the device is determined, and the underwater auxiliary unit and the collecting unit are installed underwater in the determined installation mode. The upper computer control unit is arranged in a land area of the riparian zone, and a water-tight umbilical cable is used to complete electric and signal transmission between the upper computer control unit and the underwater auxiliary unit; the working state of the collecting unit, the monitored data of the collecting unit and the control of the collecting unit are displayed in real time through the upper computer control unit.

2. The method of claim 1, wherein, 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 through the water pumping unit. The interstitial water enrichment unit comprises an outer layer permeation, an inner layer permeation, an interstitial water tank and a first water guide pipe; the outer layer permeation, the inner layer permeation and the interstitial water tank are sequentially connected from outside to inside, one end of the first water guide pipe is connected to the interstitial water tank, and the other end of the first water guide pipe is connected to the water pumping unit.

3. The method of claim 2, wherein, The water pumping unit comprises a second water guide pipe, an electromagnetic three-way valve, a syringe barrel, a syringe piston, a lower flat plate, a middle flat plate, an upper flat 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 guide pipe is connected to the third port, the other end of the second water guide pipe is connected to the first water guide pipe, the second port is connected to the sample collection unit, and the first port is connected to the liquid end of the syringe barrel through a pipeline; at least one support shaft is arranged between the lower flat plate and the middle flat plate, the syringe barrel is fixed and clamped by the lower flat plate and the middle flat plate, the syringe piston is arranged in the syringe barrel, the syringe piston is connected to a piston rod, one end of the piston rod is fixed to the lower end of the upper flat plate, the electric telescopic rod is fixed to the upper flat plate, and the telescopic end of the electric telescopic rod is connected to the middle flat plate.

4. The method of claim 3, wherein, The upper flat plate is provided with a piston block, and a piston rod is arranged in the piston block and fixed by a nut.

5. The method of claim 3, wherein, The water pumping unit further comprises an electromagnetic switch connected in communication with the electromagnetic three-way valve; and an electric control switch connected in communication with the electric telescopic rod.

6. The method of claim 3, wherein, The outer layer permeation and the inner layer permeation are net 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.

7. The method of claim 3, wherein, The gap water tank is annular, the bottom of the gap water tank is provided with a water-tight bottom cover, the top of the gap water tank is provided with a top cover with a water outlet connector, and the water outlet connector is connected to the first water guide pipe.

8. The method of claim 1, wherein, According to the flow velocity, water depth, water width, sediment concentration, sediment starting flow velocity and sediment density of the monitoring area, the sediment deposition thickness and the sediment scouring thickness of the monitoring area are determined through the following formula: In the formula, H 沉 represents the sediment deposition thickness, C s represents the water sediment concentration, represents the average flow velocity of the river, B represents the water width, h p represents the water depth, T represents the device setting time, represents the sediment density, represents the bottom area, H 冲 represents the sediment scouring thickness.

9. The method of claim 1, wherein, The installation mode of the underwater auxiliary unit and the collection unit is determined by the following method: If the sediment deposition thickness is 0-20 cm or the sediment scouring thickness is 0-3 cm, the installation mode is to directly install the underwater auxiliary unit and the collection unit underwater; If the sediment deposition thickness is 20-50 cm or the sediment scouring thickness is 3-8 cm, the installation mode is to install the underwater auxiliary unit and the collection unit by adding a fixed support underwater or by burying the water-tight umbilical cable below the sediment below 10 cm; If the sediment deposition thickness is greater than 50 cm or the sediment scouring thickness is greater than 8 cm, an alternative monitoring point is selected, or the installation mode is to install the underwater auxiliary unit and the collection unit underwater by adding a counterweight and a fixed support.

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