Shrub rainfall distribution measuring device and measuring method

Abstract

The invention relates to the technical field of hydrology and ecology, and discloses a shrub rainfall distribution measuring device and method.The shrub rainfall distribution measuring device comprises a crown outer rain gauge, the crown outer rain gauge is arranged on the ground outside the projection of a shrub on a horizontal plane, and the crown outer rain gauge is used for measuring the total rainfall; the number of the under-crown rain gauges is multiple, all the under-crown rain gauges are distributed around the shrub at intervals, all the under-crown rain gauges are arranged in the area covered by the projection of the shrub on the horizontal plane, and all the under-crown rain gauges are used for measuring the penetrating rainfall; the rainwater collecting device comprises a plurality of rainwater collecting devices and a stem flow rain gauge, the rainwater collecting devices are fixed on branches of shrub plants, the rainwater collecting devices are communicated with the stem flow rain gauge, and the height of the stem flow rain gauge is lower than that of the rainwater collecting devices. The plurality of under-crown rain gauges can measure the penetrating rainfall respectively, and the trapped rainfall of the shrub is calculated based on the principle of water balance, so that the measurement precision of the penetrating rainfall, the stem flow and the trapped rainfall is improved, and the real-time performance of data is ensured.

Description

Technical Field

[0001] The invention relates to the technical field of hydrological ecology, and in particular to a device and method for measuring shrub rainfall distribution. Background Art

[0002] Rainfall interception by understory shrubs is an indispensable part of forest ecohydrology. The herbaceous layer participates in the material and energy cycle of the forest ecosystem. Therefore, the study of rainfall interception in forest ecosystems is of great significance for clarifying the hydrological processes and water conservation functions of forest ecosystems.

[0003] Shrubs, as an important type of vegetation, have a significant impact on the distribution and utilization of rainfall. The rainfall at the shrub scale includes leaf interception rainfall, stem flow and canopy penetration rainfall. In the existing rainfall separation device, the measurement error of stem flow and penetration rainfall caused by the installation position of each component rainwater collection device is large. At the same time, leaf interception rainfall is difficult to measure, and the focus is on measuring single shrubs, which has not been verified in shrubs composed of complex structures.

[0004] In addition, rainfall distribution measurement devices and calculation methods are often limited to simple models and assumptions, or focus on single plants, and cannot accurately reflect the rainfall distribution characteristics of complex shrub structures. In particular, the measurement of stem flow and throughfall of complex shrubs is mostly done manually, which has the disadvantages of large engineering workload, low accuracy, poor timeliness, and failure to reflect the dynamic process of rainfall. Summary of the invention

[0005] The purpose of the present invention is to provide a scrub rainfall distribution measurement device to solve the problems of poor accuracy, poor timeliness and inability to reflect the dynamic process of rainfall in the prior art when measuring scrub rainfall distribution; the present invention also provides a scrub rainfall distribution measurement method using the scrub rainfall distribution measurement device.

[0006] In order to achieve the above object, the present invention provides a shrub rainfall distribution measurement device, comprising:

[0007] An extra-canopy rain gauge, which is set on the ground outside the horizontal projection of the bushes and is used to measure the total rainfall;

[0008] A canopy rain gauge, wherein there are a plurality of canopy rain gauges, each of which is spaced around the bush, each of which is arranged in an area covered by the bush on a horizontal plane projection, and each of which is used to measure the penetrating rainfall;

[0009] A rainwater collecting device and a stem flow rain gauge, wherein there are multiple rainwater collecting devices, each of which is fixed on a branch of a shrub plant, and the rainwater collecting device is connected to the stem flow rain gauge, and the height of the stem flow rain gauge is lower than that of the rainwater collecting device.

[0010] Preferably, the rainwater collection device comprises a funnel and a connecting hose, the funnel is wrapped around the branches of the shrub plant, one end of the connecting hose is connected to the bottom end of the funnel, and the other end is connected to the stem flow rain gauge, and a seal is also provided at the connection between the funnel and the connecting hose.

[0011] Preferably, the sealing member comprises a sealing rubber layer, and the sealing rubber layer covers the bottom end of the funnel and the outer side of the connecting hose.

[0012] Preferably, the rainwater collection device further comprises a filter, and the filter is arranged at the inlet of the funnel.

[0013] Preferably, the funnel and the connecting hose are both rubber parts.

[0014] Preferably, the inner diameter of the connecting hose is in the range of 0.8-1.5 cm.

[0015] Preferably, the branches of the shrub plant include primary branches located on the trunk, secondary branches connected to the trunk, and tertiary branches connected to the secondary branches, and each of the rainwater collection devices is arranged on the primary branches.

[0016] Preferably, there are four under-crown rain gauges, which are distributed at four locations of the bush at intervals.

[0017] The present invention also provides a method for measuring rain distribution in a bush, using the rain distribution measuring device in a bush described in any of the above technical solutions, comprising the following steps:

[0018] S1, an outer canopy rain gauge is set up on the ground outside the horizontal projection of the plant canopy of the shrub. The value measured by the outer canopy rain gauge is the total rainfall P;

[0019] S2, multiple canopy rain gauges are set up in the area covered by the horizontal projection of the plants under the shrubs, and the average rainfall measured by each canopy rain gauge is the throughfall rainfall TF;

[0020] S3, assembling a rainwater collection device on the branches of plants under each bush, the rainwater collection device is connected to a stem flow rain gauge, and the rainfall measured by the stem flow rain gauge is the stem flow SF;

[0021] S4, according to the rainfall balance principle, the intercepted rainfall I can be obtained by the formula I = P-SF-TF.

[0022] Compared with the prior art, the invention provides a device and method for measuring rainfall distribution in a bush. The advantages thereof are as follows: an outer-canopy rain gauge and an under-canopy rain gauge are used to measure the total rainfall and the through-rainfall respectively. A plurality of under-canopy rain gauges can measure the through-rainfall respectively. The through-rainfall is obtained by calculating the average value, thereby effectively reducing the influence of the leaf density of the bush on the through-rainfall and improving the measurement accuracy of the through-rainfall. A rainwater collection device is used to collect the rainwater left on the stems of the bush plants and the rainwater is transported to the stem flow rain gauge. The stem flow is obtained by the stem flow rain gauge. Due to the height of the stem flow rain gauge, the through-rainfall is measured by the rain gauge. The height is lower than that of the rainwater collection device. The rainfall collected by the rainwater collection device can be quickly transported to the stem flow rain gauge under the action of gravity, which improves the measurement accuracy of the stem flow. Based on the principle of water balance, the intercepted rainfall of the shrubbery can be calculated, which improves the measurement accuracy of the intercepted rainfall and avoids the error of the intercepted rainfall caused by the complex measurement and collection methods. The rainwater collection device and the stem flow rain gauge can monitor the stem flow in real time, ensure the real-time nature of the data, realize the automatic monitoring of the stem flow, and the measurement results can reflect the dynamic change process of the stem flow and the time lag effect and other information. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a structural schematic diagram of the shrub rainfall distribution measurement device of the present invention;

[0024] Figure 2 yes Figure 1 A top view of the shrub rainfall distribution measuring device;

[0025] Figure 3 yes Figure 1 Schematic diagram of the arrangement of under-canopy rain gauges for measuring shrub rainfall distribution;

[0026] Figure 4 yes Figure 1 Schematic diagram of the arrangement of rainwater collection devices and stem flow rain gauges of the shrub rainfall distribution measurement device;

[0027] Figure 5 yes Figure 4 A partial enlarged schematic diagram of the rainwater collection device and stem flow rain gauge.

[0028] In the figure, 1. outer crown rain gauge, 2. funnel, 3. filter screen, 4. connecting hose, 5. stem flow rain gauge, 6. under-crown rain gauge, 7. sealant layer. DETAILED DESCRIPTION

[0029] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0030] A preferred embodiment of a bush rainfall distribution measuring device of the present invention is as follows: Figure 1 As shown in the figure, the shrub rainfall distribution measurement device includes an outer canopy rain gauge 1, an under-canopy rain gauge 6, a rainwater collection device and a stem flow rain gauge 5.

[0031] The outer canopy rain gauge 1 is set on the ground outside the projection of the bush on the horizontal plane. When it rains, since there is no bush directly above the outer canopy rain gauge 1, the rain can fall directly on the outer canopy rain gauge 1, so the rainfall measured by the outer canopy rain gauge 1 is the total rainfall. According to the rainfall balance principle, the total rainfall = through rainfall + stem flow + intercepted rainfall. In this embodiment, the total rainfall is P, the through rainfall is TF, the stem flow is SF, and the intercepted rainfall is I, then P = TF + SF + I.

[0032] The canopy rain gauge 6 is arranged in the area covered by the projection of the bush on the horizontal plane. The rainfall measured by the canopy rain gauge 6 is the rainfall after the rainfall penetrates the branches and leaves of the bush plants. Therefore, the canopy rain gauge 6 is used to measure the penetrating rainfall.

[0033] There are multiple canopy rain gauges 6, each of which is distributed around the bush at intervals, and each canopy rain gauge 6 measures the through-rainfall separately. Affected by the leaf density of the bush plants, the canopy rainfall at different positions in a unit time period will be different. Multiple canopy rain gauges 6 are set to measure the through-rainfall separately, and the through-rainfall is obtained by calculating the average value measured by each canopy rain gauge 6, which can improve the measurement accuracy of the through-rainfall. According to the density characteristics of the leaves of the bush plants, the number of canopy rain gauges 6 can be appropriately increased to further improve the measurement accuracy of the through-rainfall.

[0034] There are multiple rainwater collection devices, each of which is fixed on a branch of a bush plant, and is used to collect rainwater flowing along the branches of the bush plant. Since there are many branches of the bush plant, each rainwater collection device collects rainwater flowing on different branches respectively, and the sum of the collected rainwater is the amount of rain flowing along the stem of the bush, which is also the stem flow rate.

[0035] Each rainwater collecting device is connected to the stem flow rain gauge 5. The height of the stem flow rain gauge 5 is lower than the height of the rainwater collecting device. The rainfall collected by the rainwater collecting device can flow into the stem flow rain gauge 5 by itself under the action of gravity, avoiding residue in the rainwater collecting device and improving the measurement accuracy of the stem flow.

[0036] In this embodiment, the outer crown rain gauge 1, the under-crown rain gauge 6, and the stem flow rain gauge 5 are all tipping bucket rain gauges, which have a simple mechanical structure, a low failure rate, high measurement accuracy, and a wide range of applications. Among them, a rain cover is set on the top of the stem flow rain gauge 5, and the rain cover is made of stainless steel to prevent penetrating raindrops from falling, and at the same time, it can also reduce the evaporation of rainfall, thereby improving the measurement accuracy of the stem flow. In addition, the rainwater collection device can collect rainwater flowing on the stems of the bushes in real time, and transport the rainwater to the stem flow rain gauge 5 in real time, ensuring the accuracy of data measurement and the real-time nature of recording, realizing automatic monitoring of the stem flow, and significantly improving work efficiency.

[0037] The shrub rainfall distribution measurement device adopts an outer canopy rain gauge 1 and an under-canopy rain gauge 6 to measure the total rainfall and the through-rainfall respectively. A plurality of under-canopy rain gauges 6 can measure the through-rainfall respectively, and the through-rainfall is obtained by calculating the average value, which effectively reduces the influence of the leaf density of the shrub on the through-rainfall and improves the measurement accuracy of the through-rainfall. A rainwater collection device is used to collect the rainwater left on the stems of the shrub plants, and the rainwater is transported to the stem flow rain gauge 5, and the stem flow is obtained by the stem flow rain gauge 5. Since the height of the stem flow rain gauge 5 is lower than the height of the rainwater collection device, The rainfall collected by the rainwater collection device can be quickly transported to the stem flow rain gauge 5 under the action of gravity, thereby improving the measurement accuracy of the stem flow. Based on the principle of water balance, the intercepted rainfall of the bush can be calculated, thereby improving the measurement accuracy of the intercepted rainfall and avoiding the error of the intercepted rainfall caused by the complex measurement and collection methods. The rainwater collection device and the stem flow rain gauge 5 can monitor the stem flow in real time, ensuring the real-time nature of the data and realizing the automatic monitoring of the stem flow. The measurement results can reflect the dynamic change process of the stem flow and the time lag effect and other information.

[0038] Preferably, the rainwater collection device includes a funnel 2 and a connecting hose 4, the funnel 2 is wrapped around the branches of the shrub plant, one end of the connecting hose 4 is connected to the bottom end of the funnel 2, and the other end is connected to the stem flow rain gauge 5, and a seal is also provided at the connection between the funnel 2 and the connecting hose 4.

[0039] The funnel 2 of the rainwater collection device is wrapped around the branches of the bush plant, and the bottom end of the funnel 2 is connected to the stem flow rain gauge 5 through the connecting hose 4. The funnel 2 wraps around the branches of the bush plant, and can collect rainwater from all directions of the branches, reduce rain loss, and improve the measurement accuracy of stem flow rainfall. In this embodiment, when the rainwater collection device is installed, the funnel 2 is cut open to wrap all the stems that need to be measured.

[0040] A seal is provided at the connection between the funnel 2 and the connecting hose 4, and the seal seals the connection so that the funnel 2 and the connecting hose 4 form a dense and watertight rainwater collection device, thereby reducing rainwater loss and improving the accuracy of the measurement result.

[0041] Preferably, the sealing member comprises a sealing rubber layer 7 , and the sealing rubber layer 7 is coated on the bottom end of the funnel 2 and the outer side of the connecting hose 4 .

[0042] The sealant layer 7 forms a seal, which can well fill the gap between the funnel 2 and the connecting hose 4, and can also seal the small opening cut by the funnel 2 when wrapping the stem to prevent rainwater from leaking through the gap.

[0043] Preferably, the rainwater collection device further comprises a filter screen 3 , and the filter screen 3 is arranged at the inlet of the funnel 2 .

[0044] A filter screen 3 is arranged at the entrance of the funnel 2, and the filter screen 3 can filter out dirt, branches and leaves, etc. flowing with the rainwater to avoid clogging the funnel 2 and causing the rainwater to be lost.

[0045] Preferably, the funnel 2 and the connecting hose 4 are both rubber parts.

[0046] The rubber part has good hardness and strength, can better withstand the impact of strong wind or heavy rain, and can quickly transfer the collected rainwater, with strong timeliness, and reduce the loss of rainwater caused by the funnel 2 being damaged by rainwater.

[0047] Preferably, the inner diameter of the connecting hose 4 is in the range of 0.8-1.5 cm.

[0048] The diameter of the connecting hose 4 is 0.8-1.5 cm. By increasing the inner diameter of the connecting hose 4, rainwater can enter the stem flow rain gauge 5 from the connecting hose 4 as quickly as possible, thereby avoiding evaporation loss of rainwater when it is collected and accumulated, and improving measurement accuracy. In this embodiment, the inner diameter of the connecting hose 4 is 1 cm.

[0049] Preferably, the branches of the shrub plant include primary branches located on the trunk, secondary branches connected to the trunk, and tertiary branches connected to the secondary branches, and each rainwater collection device is arranged on the primary branches.

[0050] The branches of the bush plants are divided into primary branches, secondary branches and tertiary branches from the base fork to the crown. Rainwater will gather on the primary branches when flowing along the branches of the bush. Therefore, the rainwater collection devices are arranged on the primary branches to improve the rainwater collection efficiency. In this embodiment, a rainwater collection device is arranged on each primary branch to ensure the accuracy of rainwater measurement.

[0051] Preferably, there are four under-crown rain gauges 6, and the four under-crown rain gauges 6 are distributed at four locations of the bush at intervals.

[0052] In this embodiment, four under-crown rain gauges 6 are specifically distributed in the east, south, west, and north directions of the bush. Usually, due to the influence of light, rain, etc., the leaf density of bush plants in the east, south, west, and north directions will have certain differences. The four under-crown rain gauges 6 are arranged according to the directions to reduce the influence of leaf density on the penetrating rainfall.

[0053] The present invention also provides a preferred embodiment of a method for measuring rain distribution in a bush, that is, a method for using the above-mentioned rain distribution measuring device in a bush, comprising the following steps:

[0054] S1, an outer canopy rain gauge 1 is installed on the ground outside the horizontal projection of the plant canopy of the shrub, and the value measured by the outer canopy rain gauge 1 is the total rainfall P;

[0055] S2, multiple canopy rain gauges 6 are set in the area covered by the horizontal projection of the plants under the bushes, and the average rainfall measured by each canopy rain gauge 6 is the throughfall rainfall TF;

[0056] S3, assembling a rainwater collection device on the branches of plants under each bush, the rainwater collection device is connected to the stem flow rain gauge 5, and the rainfall measured by the stem flow rain gauge 5 is the stem flow SF;

[0057] S4, according to the rainfall balance principle, the intercepted rainfall I can be obtained by the formula I = P-SF-TF.

[0058] In this embodiment, four canopy rain gauges 6 are arranged in step S2, and the four canopy rain gauges 6 are respectively arranged in the east, south, west and north directions of the bush. In other embodiments, the specific number of canopy rain gauges 6 can be appropriately increased according to the canopy density of the bush.

[0059] In step S3, the bush vegetation is divided into primary branches, secondary branches and tertiary branches from the base fork to the crown (those exceeding the third level are also merged into the third level), the number of all primary branches in the bush is counted, a small hole is cut in the funnel 2 of the rainwater collection device, and then the funnel 2 is wrapped around the stems of all the primary branches respectively; the bottom end of the funnel 2 is connected to the stem flow rain gauge 5 through the connecting hose 4, and the top of the stem flow rain gauge 5 is covered by a rain cover to prevent raindrops from penetrating.

[0060] In summary, the embodiment of the present invention provides a shrub rainfall distribution measurement device and measurement method, which adopts an outer canopy rain gauge and an under-canopy rain gauge to respectively measure the total rainfall and the through-rainfall, and multiple under-canopy rain gauges can respectively measure the through-rainfall, and the through-rainfall is obtained by calculating the average value, which effectively reduces the influence of the leaf density of the shrub on the through-rainfall, and improves the measurement accuracy of the through-rainfall. A rainwater collection device is used to collect rainwater left on the stems of the shrub plants, and the rainwater is transported to the stem flow rain gauge, and the stem flow is obtained by the stem flow rain gauge. Since the height of the stem flow rain gauge is lower than the rainwater The height of the collection device, the rainfall collected by the rainwater collection device can be quickly transported to the stem flow rain gauge under the action of gravity, which improves the measurement accuracy of the stem flow. Based on the principle of water balance, the intercepted rainfall of the shrubbery can be calculated, which improves the measurement accuracy of the intercepted rainfall and avoids the error of the intercepted rainfall caused by the complex measurement and collection methods. The rainwater collection device and the stem flow rain gauge can monitor the stem flow in real time, ensure the real-time nature of the data, and realize the automatic monitoring of the stem flow. The measurement results can reflect the dynamic change process of the stem flow and the time lag effect and other information.

[0061] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the scope of protection of the present invention.

Claims

1. A shrub rainfall distribution measurement device, characterized in that: include: An extra-canopy rain gauge (1), the extra-canopy rain gauge (1) being arranged on the ground outside the horizontal projection of the bush, the extra-canopy rain gauge (1) being used to measure the total rainfall; A canopy rain gauge (6), wherein there are a plurality of canopy rain gauges (6), each of which is distributed at intervals around the bush, each of which is arranged in an area covered by the bush on a horizontal plane projection, and each of which is used to measure the penetrating rainfall; A rainwater collection device and a stem flow rain gauge (5), wherein there are a plurality of rainwater collection devices, each of which is fixed on a branch of a bush plant, the rainwater collection device is connected to the stem flow rain gauge (5), and the height of the stem flow rain gauge (5) is lower than the height of the rainwater collection device.

2. The device for measuring the rainfall distribution in bushes according to claim 1, characterized in that: The rainwater collection device comprises a funnel (2) and a connecting hose (4); the funnel (2) is wrapped around the branches of a bush plant; one end of the connecting hose (4) is connected to the bottom end of the funnel (2) and the other end is connected to the stem flow rain gauge (5); a sealing member is also provided at the connection between the funnel (2) and the connecting hose (4).

3. The shrub rainfall distribution measuring device according to claim 2, characterized in that: The sealing component comprises a sealing rubber layer (7), and the sealing rubber layer (7) covers the bottom end of the funnel (2) and the outer side of the connecting hose (4).

4. The shrub rainfall distribution measuring device according to claim 2, characterized in that: The rainwater collection device further comprises a filter screen (3), and the filter screen (3) is arranged at the entrance of the funnel (2).

5. The shrub rainfall distribution measuring device according to claim 2, characterized in that: The funnel (2) and the connecting hose (4) are both rubber parts.

6. The device for measuring the rainfall distribution in bushes according to claim 2, characterized in that: The inner diameter of the connecting hose (4) is in the range of 0.8-1.5 cm.

7. The device for measuring the rainfall distribution in bushes according to any one of claims 1 to 6, characterized in that: The branches of the shrub plant include primary branches located on the trunk, secondary branches connected to the trunk, and tertiary branches connected to the secondary branches, and each of the rainwater collection devices is arranged on the primary branches.

8. The device for measuring rain distribution in bushes according to any one of claims 1 to 6, characterized in that: There are four under-crown rain gauges (6), which are distributed at intervals at four locations of the bush.

9. A method for measuring rain distribution in thickets, using the device for measuring rain distribution in thickets as claimed in any one of claims 1 to 8, characterized in that: The following steps are involved: S1, an outer canopy rain gauge (1) is installed on the ground outside the horizontal projection of the plant canopy of the shrub, and the value measured by the outer canopy rain gauge (1) is the total rainfall P; S2, multiple canopy rain gauges (6) are set in the area covered by the horizontal projection of the plants under the bushes, and the average rainfall measured by each canopy rain gauge (6) is the throughfall rainfall TF; S3, installing a rainwater collection device on the branches of plants under each bush, the rainwater collection device is connected to the stem flow rain gauge (5), and the rainfall measured by the stem flow rain gauge (5) is the stem flow SF; S4, according to the rainfall balance principle, the intercepted rainfall I can be obtained by the formula I = P-SF-TF.

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