A dynamic monitoring device for groundwater level and water quality in sandy land

Abstract

The present invention discloses a device for dynamically monitoring the water quality of groundwater level in sandy land, which relates to the technical field of groundwater level monitoring and may include: a monitoring well, wherein a plurality of monitoring wells are provided; a monitoring well pipe is provided in the monitoring well, a water inlet wall hole is provided at the lower part of the monitoring well pipe, and a sand filter net is wrapped around the water inlet wall hole; a water level gauge and a water sample collector are provided in the monitoring well, and a first plug is provided at the bottom of the monitoring well. The present invention discovers the dynamic relationship between sand dunes, sand-fixing vegetation, water level and water quality through real-time monitoring of water level changes and analysis of water samples extracted during the interval period, and provides a theoretical basis and technical support for vegetation restoration in desertified areas in combination with regional climate change.

Description

Technical Field

[0001] The invention relates to the technical field of groundwater level monitoring, in particular to a device for dynamically monitoring the water quality of groundwater level in sandy land. Background Art

[0002] Sandy land relies on the sand layer of varying thickness to receive and store natural precipitation. Since sandy land is located in a semi-arid area, evaporation is strong and groundwater level changes are extremely active, especially the shallow groundwater level is closely related to precipitation, vegetation transpiration, and evaporation on the dune surface; mastering the dynamic changes of groundwater level in sandy land has a high indicative effect on the fixation and activation of sand dunes in sandy land. At the same time, the water quality of sand dunes is also related to the growth of sand-fixing plant species and vegetation structure. It can be seen that dynamic monitoring of groundwater level and water quality in sandy land is an important means to study the changes in groundwater level, vegetation restoration and desertification dynamics in sandy land.

[0003] There are many methods for groundwater level monitoring, such as geophysical exploration, geochemical exploration, remote sensing, seismic waves, electrical measurement, field investigation, analogy, etc. However, most of these methods require large-scale instruments and equipment, high-specification monitoring wells, high monitoring costs, difficulty in implementing continuous monitoring, and difficulty in achieving multi-point coordinated monitoring. Summary of the invention

[0004] The purpose of the present invention is to provide a device for dynamically monitoring the water quality of groundwater level in sandy land to solve the above problems existing in the prior art.

[0005] To achieve the above-mentioned purpose, the present invention provides the following scheme: The present invention provides a device for dynamically monitoring the water quality of groundwater level in sandy land, including a monitoring well, wherein a plurality of monitoring wells are provided; a monitoring well pipe is provided in the monitoring well, a water inlet wall hole is provided at the lower part of the monitoring well pipe, and a sand filter net is wrapped around the water inlet wall hole; a water level gauge and a water sample collector are provided in the monitoring well, and a first plug is provided at the bottom of the monitoring well pipe.

[0006] Preferably, the monitoring well is located at a downhill position of the sand dune, and the monitoring well is 5 m deep.

[0007] Preferably, the monitoring well pipe is a PVC pipe, and the top of the monitoring well pipe protrudes out of the sand surface.

[0008] Preferably, a protective cover is provided on the top of the monitoring well pipe.

[0009] Preferably, the water level meter adopts a HOBO U20-001-04 water level meter which can be continuously monitored.

[0010] Preferably, the water level meter is suspended by a tension wire 20 cm above the bottom of the monitoring well.

[0011] Preferably, the water sample collector comprises a water extractor, and the water extractor is suspended in the monitoring well by a pull line, and a weight is pulled under the bottom of the water extractor.

[0012] Preferably, the water extractor is a cylinder made of PVC material and is suspended 30 cm above the bottom of the monitoring well.

[0013] Preferably, the monitoring wells are arranged at multiple points around the windward slope and leeward slope of a sand dune or an area of ​​the same site type or an area of ​​the same vegetation type.

[0014] Preferably, there are two monitoring wells, which are respectively arranged at the downslope of the windward slope and the leeward slope of the sand dune.

[0015] Compared with the prior art, the present invention has achieved the following technical effects:

[0016] 1. The location of the monitoring well is not easily submerged by seasonal water accumulation in the lowlands between hills;

[0017] 2. The depth of the monitoring well can be fully reduced, making the construction of the monitoring well simpler and less costly;

[0018] 3. Monitoring wells are placed downslope of the sand dunes to monitor the changes in underground water level and water quality. At the same time, multiple points (monitoring wells) are arranged around a complete sand dune or the same site type area, which can fully reflect the changing laws (characteristics) of groundwater level and water quality in a certain area of ​​the sand land;

[0019] 4. The monitoring well pipe material should be made of cheap and lightweight PVC pipe material, which is more convenient to transport in sandy areas and greatly facilitates construction operations. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] 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 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 these drawings without paying creative work.

[0021] Figure 1 It is a front view of the device for dynamically monitoring the groundwater level and water quality in sandy land according to the present invention;

[0022] Figure 2 It is a bottom schematic diagram of the monitoring well of the present invention;

[0023] Figure 3 It is a schematic diagram of the installation of the water level meter of the present invention;

[0024] Figure 4 It is a structural schematic diagram of the water sample collector of the present invention;

[0025] Figure 5 This is a schematic diagram of the aboveground part of the monitoring well of the present invention;

[0026] Among them, 1 is a sand dune, 2 is a protective cover, 3 is a monitoring well pipe, 4 is a pull wire, 5 is a sand filter, 6 is a water sample collector, 7 is a water level gauge, 8 is a first plug, 9 is a monitoring well, 10 is a water inlet wall hole, 11 is a pull wire ring, 12 is an annular guard, 13 is a direct joint, 14 is a baffle, 15 is a weight, 16 is a second plug, and 17 is a clamping ring. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] Embodiment 1

[0030] like Figure 1-5 As shown, this embodiment provides a device for dynamically monitoring the groundwater level and water quality in sandy land, including monitoring wells, wherein a plurality of monitoring wells are provided; a monitoring well pipe is provided in the monitoring well, a water inlet wall hole is provided at the lower portion of the monitoring well pipe, and a sand filter net is wrapped around the water inlet wall hole; a water level gauge and a water sample collector are provided in the monitoring well, and a first plug is provided at the bottom of the monitoring well pipe.

[0031] The construction steps of the sand groundwater phreatic level water quality dynamic monitoring device in this embodiment are as follows:

[0032] Selection of monitoring well location: The groundwater level in sandy land is shallow, so deep wells are not needed for groundwater level monitoring. In this embodiment, only the changes in the underground water level, which is closely related to the moisture in the sand dunes, are monitored. Therefore, the depth of the monitoring well is usually about 5m. The monitoring well is located on the downslope of the sand dunes, that is, 0.5 to 0.8m above the low ground level between dunes.

[0033] Monitoring wells are arranged at multiple points: Monitoring wells are arranged at multiple points around the windward and leeward slopes of an independent sand dune or a small area with the same site type or the same vegetation type, so as to achieve coordinated submission of monitoring data from multiple monitoring wells.

[0034] In this embodiment, Figure 1As shown, preferably, two monitoring wells are provided, which are respectively provided at the downslope of the windward slope and the leeward slope of the sand dune.

[0035] Drilling monitoring wells: Use small drilling machinery to drill a well with a depth of 5m and a diameter of 10cm at the well site. Figure 1 .

[0036] Select monitoring well pipe: Choose PVC pipe, DN110, φ10cm, length 5m; drill water wall holes (φ5; 50 / cm 2 ), wrap a 120-mesh sand filter net outside the water inlet wall hole; and add a first plug made of PVC material at the bottom of the monitoring well pipe; Figure 1 and Figure 2 shown.

[0037] Lower the monitoring well pipe: The well pipe should be lowered steadily to prevent the sand filter from falling off. Leave a 10-15 cm long PVC monitoring well pipe on the sand surface and number the monitoring wells where the sand surface is exposed. Figure 2 .

[0038] Water level gauge: Choose the HOBO U20-001-04 model water level gauge.

[0039] Water level meter hanging: hang the water level meter with a pull line, and the water level meter is hung 20cm above the bottom of the water layer in the monitoring well pipe. Figure 1 and 3 .

[0040] Water level monitoring: Start the water level meter and set the monitoring frequency according to research needs.

[0041] Water sample collector: After the water level meter is placed at the corresponding position in the monitoring well, the water collector is placed. The water collector is suspended by a pull line and placed 30 cm above the bottom of the monitoring well, that is, above the water level meter. The water collector is a PVC cylinder with a height of 30 cm and a diameter of 5 cm. In order to keep the water collector in a stable monitoring position, a sealed heavy object is pulled under it; Figure 1 and Figure 4 .

[0042] Specifically, an annular guard is provided on the top of the water dispenser, and a pull wire ring is provided on the annular guard for connecting the pull wire; the bottom of the water dispenser is connected to a sealed heavy object through a direct joint, a baffle is provided above the heavy object, and a second plug is installed at the bottom; the pull wire, water dispenser and heavy object can also be connected by other connection structures.

[0043] In this embodiment, the pull wire is a steel wire rope made of 304 stainless steel.

[0044] Water quality monitoring: Take water samples through a water dispenser and conduct laboratory testing and analysis. Set the monitoring frequency according to research needs.

[0045] Multi-point coordinated monitoring and analysis of spatial and temporal changes in water level and water quality:

[0046] Analyze the spatial pattern of water level and water quality in sandy land or around sand dunes according to the spatial monitoring points (monitoring wells); analyze the relationship between changes in sandy land or sand dunes or sandy land vegetation and changes in water level and water quality according to the monitoring frequency (time point).

[0047] Protective cover: After the water level meter and water dispenser are placed in the monitoring well, the exposed part of the monitoring well pipe is sealed with a protective cover. The height of the protective cover is 20 cm. Be careful not to let sand and other debris enter the monitoring well. Figure 5 .

[0048] In this embodiment, if Figure 5 As shown, a hole is punched on the top of the pipe wall of the monitoring well pipe, and a pull wire is suspended in the hole. The pull wire is connected with a clamp ring and suspended by a thin steel bar passing through the clamp ring.

[0049] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A device for dynamic monitoring of groundwater level and water quality in sandy land, characterized by: It comprises monitoring wells, wherein a plurality of monitoring wells are provided, and the well points of the monitoring wells are provided at the downslope of the sand dunes, and the depth of the monitoring wells is 5m; a monitoring well pipe is provided in the monitoring well, and a water inlet wall hole is provided at the lower part of the monitoring well pipe, and a sand filter net is wrapped around the water inlet wall hole; a water level gauge and a water sample collector are provided in the monitoring well, and a first plug is provided at the bottom of the monitoring well pipe, and the water sample collector comprises a water extractor, and the water extractor is suspended in the monitoring well by a pull wire, and a weight is pulled under the bottom of the water extractor, and a hole is punched at the top of the pipe wall of the monitoring well pipe, and the pull wire is suspended in the hole, and the pull wire is connected with a clamp ring, and is suspended by a thin steel bar crossing the clamp ring; the monitoring wells are arranged at multiple points around the windward slope and the leeward slope of a sand dune.

2. The device for dynamic monitoring of groundwater level and water quality in sandy land according to claim 1, characterized in that: The monitoring well pipe is a PVC pipe, and the top of the monitoring well pipe protrudes out of the sand surface.

3. The device for dynamic monitoring of groundwater level and water quality in sandy land according to claim 2, characterized in that: A protective cover is arranged on the top of the monitoring well pipe.

4. The device for dynamic monitoring of groundwater level and water quality in sandy land according to claim 1, characterized in that: The water level meter adopts the HOBO U20-001-04 water level meter which can be continuously monitored.

5. The device for dynamic monitoring of groundwater level and water quality in sandy land according to claim 4, characterized in that: The water level meter is suspended by a tension wire 20 cm above the bottom of the monitoring well.

6. The device for dynamic monitoring of groundwater level and water quality in sandy land according to claim 1, characterized in that: The water extractor is a cylinder made of PVC material and is suspended 30 cm above the bottom of the monitoring well.

7. The device for dynamic monitoring of groundwater level and water quality in sandy land according to claim 1, characterized in that: There are two monitoring wells, which are respectively arranged at the downslope positions of the windward slope and the leeward slope of the sand dune.

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