Correction method of sediment data in typical water-sediment series of cascade reservoirs

Abstract

The application relates to a correction method of sand amount data in a typical water and sand series of cascade reservoirs, and is characterized by comprising the following steps: collecting long-series water and sand measured data of control hydrological stations in a research range of the cascade reservoirs and data of prediction results of future water and sand amounts in existing literatures; analyzing and determining a critical time node at which a water and sand process of the control hydrological stations in the research range of the cascade reservoirs is obviously affected by operation of built large reservoirs; selecting a first typical water and sand series in a measured water and sand process before the critical time node; selecting a second typical water and sand series in a measured water and sand process after the critical time node, and restoring sand amount to eliminate the sand blocking effect of the built large reservoirs; and obtaining a final typical water and sand series after correction of the sand amount data. The application can solve the problem of the typical water and sand series required by water and sand regulation simulation calculation of the cascade reservoirs, and can provide technical support for scientific regulation of the cascade reservoirs.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of water conservancy engineering, and more particularly to a correction method for sediment data in a typical water-sediment series of cascade reservoirs. BACKGROUND

[0002] Cascade reservoirs have been built in various river basins. To determine the size of the reservoirs, different typical water-sediment series may be used by each reservoir in the feasibility study stage to study the sediment deposition problem of each reservoir. For the cascade reservoirs that have been built, when the sediment erosion and deposition impact of joint scheduling of the cascade reservoirs is studied, a unified typical water-sediment series needs to be used. With the continuous construction of cascade reservoirs and the continuous development of soil and water conservation work, at present, the runoff of each river basin changes little or decreases slightly, but the sediment discharge decreases significantly. When selecting a typical water-sediment series of cascade reservoirs, in order to ensure that the selected typical water-sediment series of cascade reservoirs is not affected by the water storage and sediment blocking of the built large reservoirs in the river basin, the typical water-sediment series is often selected before the critical time node when the built large reservoirs in the river basin are completed. Although the selected typical series ensures that the water-sediment process is a natural measured process, the sediment value often cannot reflect the change of the sediment production and transport environment of the river basin with decreasing sediment. At this time, it is necessary to correct the sediment of the typical water-sediment series selected before the critical time node, so that the water-sediment of the final typical water-sediment series after the correction of the sediment data is representative. SUMMARY

[0003] The purpose of the embodiment of the present application is to provide a correction method for sediment data in a typical water-sediment series of cascade reservoirs, which can solve the problem of insufficient representativeness of the sediment data in the typical water-sediment series of cascade reservoirs in the prior art.

[0004] To achieve the above-mentioned purpose, the present application provides the following technical scheme:

[0005] The embodiment of the present application provides a correction method for sediment data in a typical water-sediment series of cascade reservoirs, comprising the following steps:

[0006] Step 1, collecting water-sediment measured data of a long series of control hydrological stations in the research range of cascade reservoirs and data about future water-sediment prediction results in existing literature;

[0007] Step 2, analyzing and determining a critical time node at which the water-sediment process of the control hydrological stations in the research range of the cascade reservoirs is obviously affected by the operation of the built large reservoirs;

[0008] Step 3, selecting a first typical water-sediment series in the measured water-sediment process before the critical time node;

[0009] Step 4, after the critical time point, a second typical water and sediment series is selected from the measured water and sediment process, and the sediment amount is restored to eliminate the sand blocking effect of the built large reservoir;

[0010] Step 5, the annual sediment amount value of the second typical water and sediment series selected in step 4 is used to replace the annual sediment amount value of the first typical water and sediment series selected in step 3, and then the final typical water and sediment series after the sediment amount data is corrected is obtained.

[0011] In the step 1, the hydrological stations needing to collect data include the control stations of the trunk stream and branch stream of the cascade reservoir, the hydrological stations along the trunk stream, and the water and sediment data since the station is built; the future water and sediment amount prediction result data includes the runoff and sediment transport amount data of the control stations and the interval branch stream.

[0012] In the step 2, the built large reservoir is located on the trunk stream upstream of the cascade reservoir or the main reservoir inlet branch stream, and the built large reservoir can change the natural water and sediment process.

[0013] In the step 3, the first typical water and sediment series is selected from the measured water and sediment process before the critical time point, and can reflect the latest change of the water and sediment production and transport under the underlying surface condition of the basin.

[0014] In the step 4, the annual sediment amount of the second typical water and sediment series can reflect the current actual and future trend.

[0015] Compared with the prior art, the beneficial effects of the present application are:

[0016] The present application can obtain a correction method of the sediment amount data in the typical water and sediment series of the cascade reservoir, can improve the representativeness of the sediment amount data in the typical water and sediment series of the cascade reservoir, and provides technical support for the scientific scheduling of the cascade reservoir, and the method is suitable for the correction of the sediment amount data in the typical water and sediment series of the cascade reservoir of each basin. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments of the present application, and it should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation to the scope, and for the ordinary skilled in the art, other related drawings can also be obtained without paying creative labor on the basis of these drawings.

[0018] Figure 1 The method flowchart of the embodiments of the present application. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application. It should be noted that similar reference numerals and letters represent similar items in the drawings below, and therefore, once an item is defined in one drawing, it need not be further defined and explained in subsequent drawings.

[0020] The terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by "comprises a... " does not, without more constraints, exclude the existence of additional identical elements in the process, method, article, or apparatus that comprises the element.

[0021] The terms "first", "second", and the like are used only to distinguish one entity or operation from another entity or operation, and do not imply or suggest relative importance, and cannot be understood as requiring or suggesting any such actual relationship or order between the entities or operations.

[0022] As shown in Figure 1 A method for correcting sand data in a typical water-sediment series of a cascade reservoir, comprising the following steps:

[0023] Step 1, collecting long-term measured water-sediment data of control hydrological stations in the study range of the cascade reservoir and the existing literature on the future water-sediment prediction results of the cascade reservoir;

[0024] Step 2, analyzing and determining the critical time node at which the water-sediment process of the control hydrological stations in the study range of the cascade reservoir is obviously affected by the operation of the built large reservoir;

[0025] Step 3, selecting a first typical water-sediment series in the measured water-sediment process before the critical time point;

[0026] Step 4, selecting a second typical water-sediment series in the measured water-sediment process after the critical time point, and restoring the sand to eliminate the sand blocking effect of the built large reservoir;

[0027] Step 5, replacing the annual sand value of the first typical water-sediment series selected in step 3 with the annual sand value of the second typical water-sediment series selected in step 4, and then obtaining the final typical water-sediment series after the sand data correction.

[0028] Example 1:

[0029] Collecting long-term measured water-sediment data of control stations of main and tributaries of JS River, collecting existing literature on future water-sediment prediction results of JS River, and the like.

[0030] The time when JS River left tributary YL River and ET reservoir began to store water and trap sediment was 1998. ET reservoir is a large reservoir and located in the main stream of YL River with large incoming water and sediment. Therefore, 1998 can be regarded as the critical time node when the water and sediment process of the control hydrological station in the research range of JS River downstream cascade reservoirs began to be obviously affected by the operation of the built large reservoir.

[0031] For a long time, SX reservoir and C River upstream cascade reservoirs have chosen 1991-2000 water and sediment series for sediment research. Considering the continuity of the research, and 1998 and 2000 are relatively close, the 1991-2000 measured water and sediment series are still selected as the typical water and sediment series before the critical time point. The natural water and sediment series from 1991 to 2000 contains different typical years such as abundant, medium, and dry. The C River middle and lower reaches also experienced large floods in 1996 and 1999. The flow process of this series is representative. The water quantity process is representative. The most important principle of selecting water and sediment series is to reflect the future trend of water and sediment. Compared with the current actual and future trend, the total sediment of the 1991-2000 natural water and sediment series is still larger, such as the annual average sediment of the JS River downstream from 1991 to 2000 is 2.945 billion tons, which is significantly more than the average of previous years (2.46 billion tons). The sediment yield of the C River upstream basin should also be reduced accordingly. Therefore, it is necessary to correct the sediment data of the C River upstream main stream and tributaries from 1991 to 2000 to reduce the sediment of the new water and sediment series, so that the sediment of the corrected water and sediment series is more in line with the current actual and future trend.

[0032] The measured annual sediment discharge and the change of sediment discharge in different periods of the JS River main stream are compared and analyzed to analyze the change of sediment discharge and the trend of water and sediment in JS River. The results are compared with the existing literature on the prediction of future water and sediment in JS River. On this basis, the 2001-2010 water and sediment process is selected as the typical water and sediment series in the measured water and sediment process after the critical time point, and the sediment of the JS River main stream downstream of the YL River inflow is restored to eliminate the influence of the built large reservoir ET reservoir. The annual average sediment value of the 2001-2010 typical series after sediment restoration is representative, which can reflect the current actual and future trend.

[0033] The annual average sediment values of the water-sediment series after sediment reduction in 2001-2010 are used to replace the annual average sediment values of the natural water-sediment series in 1991-2000, and then the "JS River 1991-2000 sediment correction series" of the sediment data after correction is obtained, and is used as the final typical water-sediment series recommended for the study of the sediment problem of the JS River cascade reservoirs. The water-sediment of the final typical water-sediment series is representative and can reflect the current actual and future trend.

[0034] Table 1 is a comparison table of runoff and sediment discharge of main hydrological stations of JS River with multi-year average values, Table 2 is a statistical table of water-sediment change trend of JS River, and Table 3 is a statistical table of typical water-sediment series of JS River along the way recommended for use.

[0035] Table 1 is a comparison table of runoff and sediment discharge of main hydrological stations of JS River with multi-year average values, Table 2 is a statistical table of water-sediment change trend of JS River, and Table 3 is a statistical table of typical water-sediment series of JS River along the way recommended for use.

[0036]

[0037] Table 2 is a statistical table of water-sediment change trend of JS River Note: The natural annual average sediment discharge of SG station, PZH station, TZL station, HT station, PS station, SG-PZH section, PZH+TZL-HT section and HT-PS section of JS River in 1991-2000 is 0.3007 million tons, 0.6599 million tons, 0.4414 million tons, 2.2334 million tons, 2.9451 million tons, 0.3292 million tons, 1.1321 million tons and 0.7117 million tons respectively.

[0038] Table 3 is a statistical table of typical water-sediment series of JS River along the way recommended for use (1991-2000 sediment correction series, without considering the natural water-sediment before the sediment interception of the cascade reservoirs of the tributaries)

[0039]

[0040] Note: The natural annual average sediment discharge of SG station, PZH station, TZL station, HT station, PS station, SG-PZH section, PZH+TZL-HT section and HT-PS section of JS River in 1991-2000 is 0.3007 million tons, 0.6599 million tons, 0.4414 million tons, 2.2334 million tons, 2.9451 million tons, 0.3292 million tons, 1.1321 million tons and 0.7117 million tons respectively.

[0041] The above merely provides an example of the present application, and is not used to limit the protection scope of the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A method for correcting sediment volume data in a typical water-sediment series of cascade reservoirs, characterized by: The following steps are involved: Step 1: Collect the measured water and sediment data from the control hydrological stations within the study area of ​​the cascade reservoirs and the prediction results of the future water and sediment volume of the cascade reservoirs in the existing literature; Step 2: Analyze and determine the critical time point at which the water-sediment process at the control hydrological station within the study area of ​​the cascade reservoir begins to be significantly affected by the operation of the existing large reservoirs; Step 3, selecting the first typical water-sediment series in the measured water-sediment process before the critical time point; Step 4: Select the second typical water-sediment series during the measured water-sediment process after the critical time point, and perform sediment reduction to eliminate the sediment interception effect of the existing large reservoir; Step 5: Use the annual average sediment volume value of the second typical water-sediment series selected in step 4 to replace the annual average sediment volume value of the first typical water-sediment series selected in step 3, thereby obtaining the final typical water-sediment series after the sediment volume data is corrected.

2. The method for correcting sediment volume data in a typical water-sediment series of cascade reservoirs according to claim 1 is characterized in that: In step 1, the hydrological stations that need to collect data include the control stations of the main and tributary rivers entering the cascade reservoirs and the hydrological stations along the main river. The water and sediment data are all data since the establishment of the station; the future water and sediment volume prediction results include the runoff and sediment transport data of each control station and the interval tributaries.

3. The method for correcting sediment quantity data in a typical water-sediment series of cascade reservoirs according to claim 1 is characterized in that: In step 2, the large-scale reservoir that has been built is located on the upstream main stream or main inflow tributary of the cascade reservoir, and the large-scale reservoir that has been built is capable of changing the natural water and sediment process.

4. The method for correcting sediment quantity data in a typical water-sediment series of cascade reservoirs according to claim 1 is characterized in that: In step 3, the first typical water and sediment series is selected from the measured water and sediment process before the critical time point, which can reflect the latest changes in the underlying surface conditions of water and sediment production in the basin.

5. The method for correcting sediment volume data in a typical water-sediment series of cascade reservoirs according to claim 1 is characterized in that: In step 4, the annual average sediment volume of the second typical water-sediment series can reflect the current reality and future trends.

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