CN105654488A - Method for estimating silt interception amount of silt dam based on GIS - Google Patents

Abstract

The invention discloses a method for estimating the silt interception amount of a silt dam based on a GIS, belonging to the field of analysis of digital terrains. In the invention, an obtained GIS image is converted into a lattice matrix; the position data of a simple interception-free river network model and the position data of the silt dam are determined according to data in the lattice matrix; then, the position data of the silt dam is corrected; therefore, the silt dam is expanded, such that an expanded silt dam is obtained; the storage capacity of the expanded silt dam is obtained based on the flow direction of a dam point in the expanded silt dam; and, with the help of the storage capacity, the silt interception amount of the expanded silt dam is finally obtained. According to the invention, the silt dam is expanded, such that the expanded silt dam according with practical conditions better is obtained; the condition that the practical calculation result can be influenced due to the fact that the silt dam only occupies one lattice in the GIS image can be avoided; furthermore, calculation of the silt interception amount is carried out in a manner of using the data in the GIS image; therefore, influence of the factors, such as the size of the deposition surface gradient, the gully slope, the shape and the deposited particle diameter, can be avoided; and thus, the calculation accuracy of the silt interception amount is ensured.

Description

A kind of silt storage dam for farmland construction based on GIS blocks silting-up evaluation method

Technical field

The invention belongs to digital Terrain Analysis field, block silting-up evaluation method in particular to a kind of silt storage dam for farmland construction based on GIS.

Background technology

Silt storage dam for farmland construction refer to build at high concentration of sediment raceway groove repair be used for control groove channel erosion, mud alluvial plain, simultaneously to reduce flood and the silt disaster gully control engineering works facility as major objective.

How silt storage dam for farmland construction on a large scale determines in investigating that silt storage dam for farmland construction blocks husky amount and there is no at present accurately and reliably and simple and practical method. The difficult point that silt storage dam for farmland construction blocks husky amount has 2 points: the first, and silt storage dam for farmland construction has a large capacity and a wide range. Mostly being the masses to build voluntarily, it does not have the originally field data of raceway groove, after becoming silted up into, the form parameter in primitive groove road cannot obtain again dam, and alluvial body border is unclear; 2nd: alluvial surface is not horizontal plane.

In the process realizing the present invention, contriver finds that prior art at least exists following problem:

Due to the size of the alluvial face gradient fall with raceway groove ratio, shape, drift particle footpath etc. relevant, that therefore cannot determine silt storage dam for farmland construction accurately blocks husky amount.

Summary of the invention

In order to solve the problem of prior art, the present invention provides a kind of silt storage dam for farmland construction based on GIS and blocks silting-up evaluation method, and the described silt storage dam for farmland construction based on GIS blocks silting-up evaluation method, comprising:

Obtain the GIS image comprising current region height value and comprise described the 2nd GIS image when forefoot area silt storage dam for farmland construction distribution plan, based on a described GIS Image Acquisition first grid lattice matrix, element in described first grid lattice matrix represents the height value of corresponding grid, based on described 2nd GIS Image Acquisition second gate lattice matrix, the element in described second gate lattice matrix represents the height value of corresponding silt storage dam for farmland construction;

Based on described first grid lattice matrix, it is determined that the simple and easy position data without interception network of waterways model;

From described second gate lattice matrix, obtain the position data of silt storage dam for farmland construction, in conjunction with the described simple and easy positional number without interception network of waterways model according to this and described first grid lattice matrix, the position data of described silt storage dam for farmland construction are revised, obtains the correction position data of described silt storage dam for farmland construction;

Correction position data according to described silt storage dam for farmland construction, in conjunction with described first grid lattice matrix and described second gate lattice matrix, determine the absolute sea level elevation value in described silt storage dam for farmland construction, based on described absolute sea level elevation value, described silt storage dam for farmland construction is carried out two-way expansion, obtain the expansion silt storage dam for farmland construction being made up of some amount dam point;

In described first grid lattice matrix, based on the flow direction at some place, described dam, it is determined that the storage capacity of described expansion silt storage dam for farmland construction;

According to described storage capacity, it is determined that described expansion silt storage dam for farmland construction block silting-up, and described silting-up of blocking is checked.

Optionally, based on described first grid lattice matrix, it is determined that the simple and easy position data without interception network of waterways model, comprising:

Calculate the gradient value of eight nearest grids of sample grid and described sample grid in described first grid lattice matrix, choose the direction corresponding with maximum gradient value as the current direction corresponding with described sample grid;

Carry out unit water catchment area accumulation along described current direction, obtain water catchment area data;

Choosing the target grid being greater than the first predetermined threshold value in described water catchment area data, the position data that described target grid is corresponding are the simple and easy position data without interception network of waterways model.

Optionally, from described second gate lattice matrix, obtain the position data of silt storage dam for farmland construction, in conjunction with the described simple and easy positional number without interception network of waterways model according to this and described first grid lattice matrix, the position data of described silt storage dam for farmland construction are revised, obtain the correction position data of described silt storage dam for farmland construction, comprising:

The position data of silt storage dam for farmland construction are determined from described second gate lattice matrix;

According to the described simple and easy model position data without the interception network of waterways, judge described described simple and easy without interception network of waterways place, whether there is silt storage dam for farmland construction;

If there is not silt storage dam for farmland construction at described simple and easy nothing interception network of waterways place, then position data according to described silt storage dam for farmland construction determine the target grid corresponding with described silt storage dam for farmland construction in described first grid lattice matrix, choose and eight the relevant grids nearest to described target grid have the replacement grid of the maximum relevant grid of unit water catchment area as described silt storage dam for farmland construction, using the correction position data of described replacement grid mapped locations data as described silt storage dam for farmland construction.

Optionally, correction position data according to described silt storage dam for farmland construction, in conjunction with described first grid lattice matrix and described second gate lattice matrix, determine the absolute sea level elevation value in described silt storage dam for farmland construction, based on described absolute sea level elevation value, described silt storage dam for farmland construction is carried out two-way expansion, obtain the expansion silt storage dam for farmland construction being made up of some amount dam point, comprising:

Described first grid lattice matrix is determined first height value corresponding with the correction position data of described silt storage dam for farmland construction, described second gate lattice matrix extracts two height value corresponding with described silt storage dam for farmland construction, according to described first height value and described 2nd height value, obtain the absolute sea level elevation value of described silt storage dam for farmland construction;

In described first grid lattice matrix, choose the neighbour's grid being positioned at the sea level elevation on the left of the corresponding grid of described silt storage dam for farmland construction correction position data higher than described absolute sea level elevation value, using described neighbour's grid as left expansion grid, described left expansion grid and the whole grids on described silt storage dam for farmland construction correction position data corresponding grid line are extended for the left dam point of described silt storage dam for farmland construction;

In described first grid lattice matrix, choose the neighbour's grid being positioned at the sea level elevation on the right side of the corresponding grid of described silt storage dam for farmland construction correction position data higher than described absolute sea level elevation value, using described neighbour's grid as right expansion grid, described right expansion grid and the whole grids on described silt storage dam for farmland construction correction position data corresponding grid line are extended for the right dam point of described silt storage dam for farmland construction;

According to described left dam point and described right dam point, obtain the expansion silt storage dam for farmland construction being made up of some amount dam point after two-way expansion.

Optionally, in described first grid lattice matrix, based on the flow direction at some place, described dam, it is determined that the storage capacity of described expansion silt storage dam for farmland construction, comprising:

From described expansion silt storage dam for farmland construction, choose sample dam point, described first grid lattice matrix is determined the sample grid corresponding with described sample dam point, obtain eight nearest with described sample grid and associate the flow direction in grid;

If the described flow direction is for pointing to described sample dam point, determine that the height value that described association grid is corresponding is less than described absolute sea level elevation value simultaneously, calculate the single-point volume of described sample dam point, described single-point volume is added in the cumulative storage capacity of described expansion silt storage dam for farmland construction, and described sample dam point is defined as reference point;

Described reference point is pointed to when the flow direction that there are eight grids around the corresponding grid of described reference point has a target to flow to, when the sea level elevation of the corresponding grid of the described target flow direction is not less than described absolute sea level elevation value simultaneously, stop storage capacity calculating, using storage capacity as described expansion silt storage dam for farmland construction of the described cumulative storage capacity that gets before.

Optionally, according to described storage capacity, it is determined that described expansion silt storage dam for farmland construction block silting-up, comprising:

Based on drainage area Vero, determined the effective holdingcapacity El of described expansion silt storage dam for farmland construction by formula one₀,

El₀=Vero �� (1-Def), formula one,

Wherein, Def is ground, dam interception coefficient, namely often collects to come in 100 materials, it is possible to retain the material ratio in ground, dam;

Effective holdingcapacity El according to described expansion silt storage dam for farmland construction₀In conjunction with formula two, it is determined that the amount of the retaining Ed of single described expansion silt storage dam for farmland construction_i,

${\mathrm{Ed}}_i=\{\begin{array}{cc}Vero\×Def& {\mathrm{El}}_0\≤Vmax\\ Vmax& {\mathrm{El}}_0>Vmax\end{array},$ Formula two,

Wherein, Vmax is the storage capacity of described silt storage dam for farmland construction;

By the amount of the retaining Ed of described single expansion silt storage dam for farmland construction_iCumulative summation, blocks silting-up Edt in conjunction with what formula three obtained described expansion silt storage dam for farmland construction,

$Edt=\underset{i=1}{\overset{n}{\Σ}}{\mathrm{Ed}}_i,$ Formula three.

Optionally, described silting-up of blocking is checked, comprising:

When forefoot area is provided with the number of dropouts El in described silt storage dam for farmland construction region described in obtaining_iAnd the number of dropouts in described silt storage dam for farmland construction region is not setDescribed total number of dropouts Elt when forefoot area is obtained according to formula four,

$Elt=\underset{i=1}{\overset{n}{\Σ}}{\mathrm{El}}_i+\underset{j=1}{\overset{m}{\Σ}}{\mathrm{Ero}}_j,$ Formula four;

Block silting-up Edt according to described total number of dropouts Elt in conjunction with described expansion silt storage dam for farmland construction, determine the described actual loss total amount Lt' when forefoot area by formula five,

Lt'=Edt+Elt, formula five;

Work as forefoot area for described, determine the theoretical loss total amount Lt when not arranging described expansion silt storage dam for farmland construction according to formula six,

$Lt=\underset{k=1}{\overset{1}{\Σ}}{E}_k,$ Formula six,

Wherein, E_kFor described when the erosion amount of each grid in first grid lattice matrix described in forefoot area, l is the total amount of grid in described first grid lattice matrix;

When described theoretical loss total amount Lt and described actual loss total amount Lt' approximately equal, the silting-up Edt that blocks of described expansion silt storage dam for farmland construction calculates accurately.

The useful effect that technical scheme provided by the invention is brought is:

Silt storage dam for farmland construction is expanded, obtain the expansion silt storage dam for farmland construction of more realistic situation, avoid silt storage dam for farmland construction in GIS image only to occupy situation that a grid can affect results of calculation, and carry out blocking the calculating of silting-up with the use of the mode of data in GIS image, the size of the alluvial face of the avoiding gradient and raceway groove than falling, the impact of shape, the factor such as drift particle footpath, ensure that the accuracy blocked silting-up and calculate.

Accompanying drawing explanation

In order to be illustrated more clearly in the technical scheme of the present invention, below the accompanying drawing used required in embodiment being described is briefly described, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skill in the art, under the prerequisite not paying creative work, it is also possible to obtain other accompanying drawing according to these accompanying drawings.

Fig. 1 is the schematic flow sheet that a kind of silt storage dam for farmland construction based on GIS provided by the invention blocks silting-up evaluation method;

Fig. 2 be a kind of silt storage dam for farmland construction based on GIS provided by the invention block the ditch basin, fragrant-flowered garlic garden of silting-up evaluation method have the incidence matrix result blocked;

Fig. 3 be a kind of silt storage dam for farmland construction based on GIS provided by the invention block the basin, butte river of silting-up evaluation method have the incidence matrix result blocked.

Embodiment

For making the structure of the present invention and advantage clearly, below in conjunction with accompanying drawing, the structure of the present invention is further described.

Embodiment one

The present invention provides a kind of silt storage dam for farmland construction based on GIS and blocks silting-up evaluation method, and the described silt storage dam for farmland construction based on GIS blocks silting-up evaluation method, and as shown in Figure 1, this evaluation method comprises:

101, obtain the GIS image comprising current region height value and comprise described the 2nd GIS image when forefoot area silt storage dam for farmland construction distribution plan, based on a described GIS Image Acquisition first grid lattice matrix, element in described first grid lattice matrix represents the height value of corresponding grid, based on described 2nd GIS Image Acquisition second gate lattice matrix, the element in described second gate lattice matrix represents the height value of corresponding silt storage dam for farmland construction;

102, based on described first grid lattice matrix, it is determined that the simple and easy position data without interception network of waterways model;

103, from described second gate lattice matrix, obtain the position data of silt storage dam for farmland construction, in conjunction with the described simple and easy positional number without interception network of waterways model according to this and described first grid lattice matrix, the position data of described silt storage dam for farmland construction are revised, obtains the correction position data of described silt storage dam for farmland construction;

104, according to the correction position data of described silt storage dam for farmland construction, in conjunction with described first grid lattice matrix and described second gate lattice matrix, determine the absolute sea level elevation value in described silt storage dam for farmland construction, based on described absolute sea level elevation value, described silt storage dam for farmland construction is carried out two-way expansion, obtain the expansion silt storage dam for farmland construction being made up of some amount dam point;

105, in described first grid lattice matrix, based on the flow direction at some place, described dam, it is determined that the storage capacity of described expansion silt storage dam for farmland construction;

106, according to described storage capacity, it is determined that described expansion silt storage dam for farmland construction block silting-up, and described silting-up of blocking is checked.

In enforcement, in order to the silting-up of blocking when forefoot area silt storage dam for farmland construction is estimated comparatively accurately, the present invention proposes a kind of evaluation method based on GIS, here GIS is geographical information system(GIS) (GeographicInformationSystem or Geo-InformationSystem, GIS), or be called " GeoscienceInformation System ", it is a kind of specific very important spatial information system. Say accurately, be under computer hardware and software system is supported, the relevant regional distribution data in earth top layer (comprising atmospheric layer) space all or in part gathered, stores, manage, computing, analysis, display and description technology system.

First, obtain a GIS image and the 2nd GIS image, the height value when forefoot area optional position can be obtained according to a GIS image, the branch's situation when silt storage dam for farmland construction in forefoot area can be determined according to the 2nd GIS image, and determine the height value of each silt storage dam for farmland construction. One GIS image and the 2nd GIS image are converted to first grid lattice matrix and second gate lattice matrix. In first grid lattice matrix, each element represents the height value of corresponding zone, and each element in second gate lattice matrix then represents the height value of corresponding zone silt storage dam for farmland construction.

Secondly, according to first grid lattice matrix, determine when the simple and easy nothing interception network of waterways model in forefoot area by the maximum slope method of falling, and determine the above-mentioned simple and easy position data without interception network of waterways model.

Then, the position data when forefoot area silt storage dam for farmland construction are extracted from second gate lattice matrix, in conjunction with the simple and easy position data without interception network of waterways model that back gets, revise when the position data of silt storage dam for farmland construction in forefoot area, it is ensured that silt storage dam for farmland construction is positioned on correct position.

Again, owing to the precision of images is limited, the silt storage dam for farmland construction information got in the 2nd GIS image can not reflect the state of true silt storage dam for farmland construction, it is thus desirable to the silt storage dam for farmland construction in the 2nd GIS image is expanded, according to the height value in first grid lattice matrix and second gate lattice matrix, silt storage dam for farmland construction is carried out two-way expansion, obtains the expansion silt storage dam for farmland construction being made up of the dam point of some amount.

Finally, according to the flow direction expanding some place, dam in silt storage dam for farmland construction, it is determined that expand the storage capacity of silt storage dam for farmland construction, so determine to expand silt storage dam for farmland construction block silting-up.

In order to guarantee that the expansion silt storage dam for farmland construction got blocks the accuracy of silting-up, in addition it is also necessary to check blocking silting-up.

Abandon in the present invention and determined that silt storage dam for farmland construction blocked the method for silting-up according to alluvial plain area in the past, but according to the concrete interception coefficient of silt storage dam for farmland construction to the estimation blocking silting-up and carrying out macroscopic view, and the situation that a grid can affect results of calculation is only occupied in order to avoid silt storage dam for farmland construction in GIS image, specially silt storage dam for farmland construction is expanded calculating before silt storage dam for farmland construction storage capacity the sea level elevation according to silt storage dam for farmland construction, obtain the expansion silt storage dam for farmland construction of more realistic situation, block silting-up what this basis row obtained silt storage dam for farmland construction, thus ensure finally to block the accuracy of silting-up calculation result.

The present invention provides a kind of silt storage dam for farmland construction based on GIS and blocks silting-up evaluation method, first the GIS image got is converted into grid matrix, determine that the simple and easy positional number without interception network of waterways model is according to this and the position data of silt storage dam for farmland construction according to the data in grid matrix, then the position data of silt storage dam for farmland construction are revised, and then silt storage dam for farmland construction carried out expansion obtain expanding silt storage dam for farmland construction, obtain expanding the storage capacity of silt storage dam for farmland construction based on the flow direction expanding dam point in silt storage dam for farmland construction, in conjunction with storage capacity finally obtain expand silt storage dam for farmland construction block silting-up, also need it to be checked to ensure to block the accuracy of silting-up. relative to prior art, silt storage dam for farmland construction is expanded by the present invention, obtain the expansion silt storage dam for farmland construction of more realistic situation, avoid silt storage dam for farmland construction in GIS image only to occupy situation that a grid can affect results of calculation, and carry out blocking the calculating of silting-up with the use of the mode of data in GIS image, the size of the alluvial face of the avoiding gradient and raceway groove than falling, the impact of shape, the factor such as drift particle footpath, ensure that the accuracy blocked silting-up and calculate.

Optionally, based on described first grid lattice matrix, it is determined that the simple and easy position data without interception network of waterways model, comprising:

Calculate the gradient value of eight nearest grids of sample grid and described sample grid in described first grid lattice matrix, choose the direction corresponding with maximum gradient value as the current direction corresponding with described sample grid;

Carry out unit water catchment area accumulation along described current direction, obtain water catchment area data;

Choosing the target grid being greater than the first predetermined threshold value in described water catchment area data, the position data that described target grid is corresponding are the simple and easy position data without interception network of waterways model.

In enforcement, in order to determine when the position data without interception network of waterways model simple and easy in forefoot area, it is necessary to perform following steps:

201, from first grid lattice matrix, sample grid is chosen, calculate eight grids nearest around sample grid gradient value separately, using the upstream position of grid corresponding for maximum gradient value as sample grid, namely point to the current direction of direction as sample grid of sample grid from the grid that maximum gradient value is corresponding.

202, the current direction got along back, taking 1 as initial unit water catchment area, carries out water catchment area and gathers, obtain the water catchment area data corresponding with each grid.

203, the target grid that water catchment area data are greater than the first predetermined threshold value is chosen, numerous target grid is combined, the region that after combination, grid is corresponding is when forefoot area is simple and easy without interception network of waterways model area, and the position data that after combination, grid is corresponding are when the simple and easy position data without interception network of waterways model of forefoot area.

It should be noted that, the water catchment area method of summary used in step 202., be the water catchment area supposed in grid A it is 1, flow to the next grid B pointed to and self there are water catchment area data, add flow to source place grid A with water catchment area data 1, the numerical value that obtains of summation is the water catchment area data of grid B, analogizes successively, until when flowing to that in path, all raster symbol-base are used up, it is determined that the water catchment area data of all grids.

This step, according to the spontaneous phenomenon of " Water seeks its own level " in nature, flowing through path when what determine current in forefoot area, gets when forefoot area is simple and easy without interception network of waterways model area, provides basic for determining the correction of silt storage dam for farmland construction position afterwards.

Optionally, from described second gate lattice matrix, obtain the position data of silt storage dam for farmland construction, in conjunction with the described simple and easy positional number without interception network of waterways model according to this and described first grid lattice matrix, the position data of described silt storage dam for farmland construction are revised, obtain the correction position data of described silt storage dam for farmland construction, comprising:

The position data of silt storage dam for farmland construction are determined from described second gate lattice matrix;

According to the described simple and easy model position data without the interception network of waterways, judge described described simple and easy without interception network of waterways place, whether there is silt storage dam for farmland construction;

If there is not silt storage dam for farmland construction at described simple and easy nothing interception network of waterways place, then position data according to described silt storage dam for farmland construction determine the target grid corresponding with described silt storage dam for farmland construction in described first grid lattice matrix, choose and eight the relevant grids nearest to described target grid have the replacement grid of the maximum relevant grid of unit water catchment area as described silt storage dam for farmland construction, using the correction position data of described replacement grid mapped locations data as described silt storage dam for farmland construction.

In enforcement, owing to GIS image taking is easily subject to the interference of multiple factor, cause the data distortion in GIS image, here in order to avoid distortion to cause the appearance of data mistake, specially the position data of silt storage dam for farmland construction in the 2nd GIS image being revised, concrete steps are as follows:

301, from second gate lattice matrix, determine the position data of silt storage dam for farmland construction.

302, according to the simple and easy model position data without the interception network of waterways, whether two the position data got front and back unanimously contrast, and judge whether there is silt storage dam for farmland construction at simple and easy nothing interception network of waterways place.

If 303 two position data are inconsistent, then judge there is not silt storage dam for farmland construction simple and easy without interception network of waterways place, now position data according to silt storage dam for farmland construction determine the target grid corresponding with silt storage dam for farmland construction in first grid lattice matrix, and choose and eight the relevant grids nearest to target grid have the replacement grid of the maximum relevant grid of unit water catchment area as silt storage dam for farmland construction, the correction position data of grid mapped locations data as silt storage dam for farmland construction will be replaced.

By above-mentioned steps, the position of silt storage dam for farmland construction is revised, carry out the calculating of subsequent step based on the correction position data of silt storage dam for farmland construction.

Optionally, correction position data according to described silt storage dam for farmland construction, in conjunction with described first grid lattice matrix and described second gate lattice matrix, determine the absolute sea level elevation value in described silt storage dam for farmland construction, based on described absolute sea level elevation value, described silt storage dam for farmland construction is carried out two-way expansion, obtain the expansion silt storage dam for farmland construction being made up of some amount dam point, comprising:

Described first grid lattice matrix is determined first height value corresponding with the correction position data of described silt storage dam for farmland construction, described second gate lattice matrix extracts two height value corresponding with described silt storage dam for farmland construction, according to described first height value and described 2nd height value, obtain the absolute sea level elevation value of described silt storage dam for farmland construction;

In described first grid lattice matrix, choose the neighbour's grid being positioned at the sea level elevation on the left of the corresponding grid of described silt storage dam for farmland construction correction position data higher than described absolute sea level elevation value, using described neighbour's grid as left expansion grid, described left expansion grid and the whole grids on described silt storage dam for farmland construction correction position data corresponding grid line are extended for the left dam point of described silt storage dam for farmland construction;

In described first grid lattice matrix, choose the neighbour's grid being positioned at the sea level elevation on the right side of the corresponding grid of described silt storage dam for farmland construction correction position data higher than described absolute sea level elevation value, using described neighbour's grid as right expansion grid, described right expansion grid and the whole grids on described silt storage dam for farmland construction correction position data corresponding grid line are extended for the right dam point of described silt storage dam for farmland construction;

According to described left dam point and described right dam point, obtain the expansion silt storage dam for farmland construction being made up of some amount dam point after two-way expansion.

In enforcement, during general record silt storage dam for farmland construction position, silt storage dam for farmland construction only accounts for a grid, but in a practical situation, silt storage dam for farmland construction occupies multiple grid. Silt storage dam for farmland construction, before calculating storage capacity, according to dam height, has been expanded by this step, and concrete steps are as follows:

401, in first grid lattice matrix, the first height value that the correction position data with silt storage dam for farmland construction are corresponding is determined, second gate lattice matrix extracts two height value corresponding with silt storage dam for farmland construction, first height value and the 2nd height value are added, absolute sea level elevation value that is that obtain and that be silt storage dam for farmland construction.

According to the 2nd height value and silt storage dam for farmland construction height Dh, in conjunction with formula

Dele=Dh+Ele₀

Calculate the absolute sea level elevation value of silt storage dam for farmland construction and the height above sea level Dele at silt storage dam for farmland construction top, in the formula of top, Ele₀It is the first height value and the height above sea level of silt storage dam for farmland construction position.

402, in first grid lattice matrix, choose the neighbour's grid being positioned at the sea level elevation on the left of the corresponding grid of silt storage dam for farmland construction correction position data higher than absolute sea level elevation value, using neighbour's grid as left expansion grid, left expansion grid and the whole grids on silt storage dam for farmland construction correction position data corresponding grid line are extended for the left dam point of silt storage dam for farmland construction.

403, in first grid lattice matrix, choose the neighbour's grid being positioned at the sea level elevation on the right side of the corresponding grid of silt storage dam for farmland construction correction position data higher than absolute sea level elevation value, using neighbour's grid as right expansion grid, right expansion grid and the whole grids on silt storage dam for farmland construction correction position data corresponding grid line are extended for the right dam point of silt storage dam for farmland construction.

404, according to left Ba Dianjiyouba point, the expansion silt storage dam for farmland construction being made up of some amount dam point after two-way expansion is obtained.

By above-mentioned steps, obtain being configured to expand silt storage dam for farmland construction by more multi-grid and dam point, being conducive to the silting-up of blocking of silt storage dam for farmland construction being calculated accurately for grid corresponding to original silt storage dam for farmland construction.

Optionally, in described first grid lattice matrix, based on the flow direction at some place, described dam, it is determined that the storage capacity of described expansion silt storage dam for farmland construction, comprising:

From described expansion silt storage dam for farmland construction, choose sample dam point, described first grid lattice matrix is determined the sample grid corresponding with described sample dam point, obtain eight nearest with described sample grid and associate the flow direction in grid;

If the described flow direction is for pointing to described sample dam point, determine that the height value that described association grid is corresponding is less than described absolute sea level elevation value simultaneously, calculate the single-point volume of described sample dam point, described single-point volume is added in the cumulative storage capacity of described expansion silt storage dam for farmland construction, and described sample dam point is defined as reference point;

Described reference point is pointed to when the flow direction that there are eight grids around the corresponding grid of described reference point has a target to flow to, when the sea level elevation of the corresponding grid of the described target flow direction is not less than described absolute sea level elevation value simultaneously, stop storage capacity calculating, using storage capacity as described expansion silt storage dam for farmland construction of the described cumulative storage capacity that gets before.

In enforcement, storage capacity is as the controling parameters of silt lodging or cross flow, and when silt lodging amount is greater than storage capacity, all silt, by all flowing through silt storage dam for farmland construction slowly, when the old metering of silt is less than storage capacity, crosses silt storage dam for farmland construction by interception coefficient cross flow. Therefore for each silt storage dam for farmland construction, all there is self a storage capacity. Determining to expand the storage capacity of silt storage dam for farmland construction in this step, concrete steps are as follows:

501, choose sample dam point from expanding silt storage dam for farmland construction, first grid lattice matrix is determined the sample grid corresponding with sample dam point, obtains eight nearest with sample grid and associate the flow direction in grid.

If 502 flow to as pointing to sample dam point, determine that the height value associating grid corresponding is less than absolute sea level elevation value simultaneously, calculate the single-point volume of sample dam point, single-point volume is added in the cumulative storage capacity expanding silt storage dam for farmland construction, and sample dam point is defined as reference point.

If flowing to sample dam point, then judge that this sea level elevation is less than the absolute High aititude height of silt storage dam for farmland construction, if the height value now associating grid corresponding is less than absolute sea level elevation value, according to formula

V_i=(Dele-Ele_i)*l²

Determine the single-point volume V of each dam point_i, the Dele in formula is the absolute sea level elevation value of silt storage dam for farmland construction, Ele_iBeing the height above sea level of i-th silt storage dam for farmland construction position, l is the length of side of silt storage dam for farmland construction residing association grid.

503, reference point is pointed to when the flow direction that there are eight grids around the corresponding grid of reference point has a target to flow to, when the sea level elevation of the corresponding grid of the target flow direction is not less than absolute sea level elevation value simultaneously, stop storage capacity calculating, using the cumulative storage capacity that gets before as the storage capacity expanding silt storage dam for farmland construction.

The flow direction simultaneously meeting eight grids around the corresponding grid of (1) reference point there is a target to flow to and points to reference point, (2) when the sea level elevation of the corresponding grid of the target flow direction is not less than this two conditions of absolute sea level elevation value, stop the cumulative of storage capacity, using the cumulative storage capacity that now obtains as the storage capacity expanding silt storage dam for farmland construction.

Optionally, according to described storage capacity, it is determined that described expansion silt storage dam for farmland construction block silting-up, comprising:

Based on drainage area Vero, determined the effective holdingcapacity El of described expansion silt storage dam for farmland construction by formula one₀,

El₀=Vero �� (1-Def), formula one

Wherein, Def is ground, dam interception coefficient, namely often collects to come in 100 materials, it is possible to retain the material ratio in ground, dam;

Effective holdingcapacity El according to described expansion silt storage dam for farmland construction₀In conjunction with formula two, it is determined that the amount of the retaining Ed of single described expansion silt storage dam for farmland construction_i,

${\mathrm{Ed}}_i=\{\begin{array}{cc}Vero\×Def& {\mathrm{El}}_0\≤Vmax\\ Vmax& {\mathrm{El}}_0>Vmax\end{array},$ Formula two

Wherein, Vmax is the storage capacity of described silt storage dam for farmland construction;

By the amount of the retaining Ed of described single expansion silt storage dam for farmland construction_iCumulative summation, blocks silting-up Edt in conjunction with what formula three obtained described expansion silt storage dam for farmland construction,

$Edt=\underset{i=1}{\overset{n}{\Σ}}{\mathrm{Ed}}_i,$ Formula three.

In enforcement, according to silt storage dam for farmland construction position, it is determined that drainage area, calculating total number of dropouts that in this basin, namely accumulative number of dropouts is pooled in dam, its value equals to be labeled as Vero taking number of dropouts special topic as the drainage area of weight.

601, based on drainage area Vero, determine to expand the effective holdingcapacity El of silt storage dam for farmland construction by formula one₀,

El₀=Vero �� (1-Def), formula one,

Wherein, Def is ground, dam interception coefficient, namely often collects to come in 100 materials, it is possible to retain the material ratio in ground, dam.

602, according to the effective holdingcapacity El expanding silt storage dam for farmland construction₀In conjunction with formula two, it is determined that the amount of the retaining Ed of single expansion silt storage dam for farmland construction_i,

${\mathrm{Ed}}_i=\{\begin{array}{cc}Vero\×Def& {\mathrm{El}}_0\≤Vmax\\ Vmax& {\mathrm{El}}_0>Vmax\end{array},$ Formula two,

Wherein, Vmax is the storage capacity of silt storage dam for farmland construction. It is apparent that as the effective holdingcapacity El expanding silt storage dam for farmland construction₀When being less than the storage capacity expanding silt storage dam for farmland construction, the amount of the retaining Ed of this expansion silt storage dam for farmland construction_iEqual the product expanding the actual amount that can intercept of silt storage dam for farmland construction i.e. drainage area Vero and tackling coefficient Def; And when expanding the effective holdingcapacity El of silt storage dam for farmland construction₀When being more than or equal to the storage capacity expanding silt storage dam for farmland construction, the amount of the retaining Ed of this expansion silt storage dam for farmland construction_iFor expanding the storage capacity Vmax of silt storage dam for farmland construction.

603, by the amount of the retaining Ed of single expansion silt storage dam for farmland construction_iCumulative summation, obtain in conjunction with formula three expand silt storage dam for farmland construction block silting-up Edt,

$Edt=\underset{i=1}{\overset{n}{\Σ}}{\mathrm{Ed}}_i,$ Formula three.

Determining the amount of the retaining Ed of single expansion silt storage dam for farmland construction_iAfter, it is seen that block, when what forefoot area all expanded silt storage dam for farmland construction, the amount of the retaining Ed that silting-up Edt is single expansion silt storage dam for farmland construction_iCumulative sum.

Optionally, described silting-up of blocking is checked, comprising:

When forefoot area is provided with the number of dropouts El in described silt storage dam for farmland construction region described in obtaining_iAnd the number of dropouts in described silt storage dam for farmland construction region is not setDescribed total number of dropouts Elt when forefoot area is obtained according to formula four,

$Elt=\underset{i=1}{\overset{n}{\Σ}}{\mathrm{El}}_i+\underset{j=1}{\overset{m}{\Σ}}{\mathrm{Ero}}_j,$ Formula four;

Block silting-up Edt according to described total number of dropouts Elt in conjunction with described expansion silt storage dam for farmland construction, determine the described actual loss total amount Lt' when forefoot area by formula five,

Lt'=Edt+Elt, formula five;

Work as forefoot area for described, determine the theoretical loss total amount Lt when not arranging described expansion silt storage dam for farmland construction according to formula six,

$Lt=\underset{k=1}{\overset{1}{\Σ}}{E}_k,$ Formula six,

Wherein, E_kFor working as the erosion amount of each grid in first grid lattice matrix in forefoot area, l is the total amount of grid in first grid lattice matrix;

When described theoretical loss total amount Lt and described actual loss total amount Lt' approximately equal, the silting-up Edt that blocks of described expansion silt storage dam for farmland construction calculates accurately.

In enforcement, by the end of back, in fact complete when forefoot area silt storage dam for farmland construction blocks the calculating of silting-up, but in order to ensure the accurate of calculation result, in addition it is also necessary to calculation result being checked, concrete checking step is as follows:

701, the number of dropouts El that forefoot area is provided with silt storage dam for farmland construction region is worked as in acquisition_iAnd the number of dropouts in silt storage dam for farmland construction region is not setThe total number of dropouts Elt when forefoot area is obtained according to formula four,

$Elt=\underset{i=1}{\overset{n}{\Σ}}{\mathrm{El}}_i+\underset{j=1}{\overset{m}{\Σ}}{\mathrm{Ero}}_j,$ Formula four.

Namely when total number of dropouts=forefoot area is provided with the number of dropouts in the number of dropouts in silt storage dam for farmland construction region+do not arrange silt storage dam for farmland construction region of forefoot area.

702, combine according to total number of dropouts Elt expand silt storage dam for farmland construction block silting-up Edt, determine the actual loss total amount Lt' when forefoot area by formula five,

Lt'=Edt+Elt, formula five.

Namely actual loss total amount=expansion silt storage dam for farmland construction block silting-up+total number of dropouts.

703, for working as forefoot area, determine do not arranging theoretical loss total amount Lt when expanding silt storage dam for farmland construction according to formula six,

$Lt=\underset{k=1}{\overset{1}{\Σ}}{E}_k,$ Formula six,

Wherein, E_kFor working as the erosion amount of each grid in first grid lattice matrix in forefoot area, l is the total amount of grid in first grid lattice matrix.

I.e. theoretical loss total amount=the first grid erosion amount+the two grid erosion amount++ kth grid erosion amount.

704, when described theoretical loss total amount Lt and described actual loss total amount Lt' approximately equal, the silting-up Edt that blocks of described expansion silt storage dam for farmland construction calculates accurately.

When theory loss total amount and actual loss total amount approximately equal, the calculating that silt storage dam for farmland construction blocks before namely thinking silting-up is accurately.

The present invention provides a kind of silt storage dam for farmland construction based on GIS and blocks silting-up evaluation method, first the GIS image got is converted into grid matrix, determine that the simple and easy positional number without interception network of waterways model is according to this and the position data of silt storage dam for farmland construction according to the data in grid matrix, then the position data of silt storage dam for farmland construction are revised, and then silt storage dam for farmland construction carried out expansion obtain expanding silt storage dam for farmland construction, obtain expanding the storage capacity of silt storage dam for farmland construction based on the flow direction expanding dam point in silt storage dam for farmland construction, in conjunction with storage capacity finally obtain expand silt storage dam for farmland construction block silting-up, also need it to be checked to ensure to block the accuracy of silting-up. relative to prior art, silt storage dam for farmland construction is expanded by the present invention, obtain the expansion silt storage dam for farmland construction of more realistic situation, avoid silt storage dam for farmland construction in GIS image only to occupy situation that a grid can affect results of calculation, and carry out blocking the calculating of silting-up with the use of the mode of data in GIS image, the size of the alluvial face of the avoiding gradient and raceway groove than falling, the impact of shape, the factor such as drift particle footpath, ensure that the accuracy blocked silting-up and calculate.

Description of test

The present invention have selected ditch basin, fragrant-flowered garlic garden and these two groups of representative dem datas of basin, butte river are tested. The incidence matrix result that the having of Jiu Yuangou is blocked is as shown in Figure 2. The incidence matrix result that the having of basin, butte river is blocked is as shown in Figure 3. In figure, grey and white portion represent the network of waterways, and color is more dark, illustrate that river course number of dropouts is more little. Silt flows to the lower left corner from the upper right corner of picture, dimmed in white behind silt storage dam for farmland construction place, illustrates that part silt is blocked, and river course number of dropouts diminishes, and causes colour-darkening.

Result evaluation and test is as shown in table 1.

Title basin, basin always the total number of dropouts in the amount of retaining basin without loss total amount when silt storage dam for farmland construction.

Basin title	Basin is the amount of retaining always	The total number of dropouts in basin	Without loss total amount when silt storage dam for farmland construction
				Jiu Yuangou	70.5249	6872.8040	6943.3290
Butte river	207613.0012	16262570.0000	16480180.0012

The silt storage dam for farmland construction in the different basin of table 1 blocks what amount unit t/ (km2*a)

Being theoretical value without loss total amount when silt storage dam for farmland construction in table, its value should about equal: basin is the total number of dropouts in the amount of retaining+basin always.

For " Jiu Yuangou "

Basin is the total number of dropouts 6872.8040=6943.3289 in the amount of retaining 70.5249+ basin always

�� is without the loss total amount 6943.3290 when silt storage dam for farmland construction.

For " butte river "

Basin is the total number of dropouts 16262570.0000=16470183.0012 in the amount of retaining 207613.0012+ basin always

�� is without the loss total amount 16480180.0012 when silt storage dam for farmland construction.

By the checking of above-mentioned data, prove that the calculating that silt storage dam for farmland construction blocks silting-up is rational.

It should be understood that the silt storage dam for farmland construction based on GIS that above-described embodiment provides blocks the embodiment that silting-up evaluation method carries out silt storage dam for farmland construction and blocks silting-up and calculate, only as blocking the explanation in actual applications of silting-up evaluation method based on the silt storage dam for farmland construction of GIS, silting-up evaluation method can also be blocked according to actual needs and by the above-mentioned silt storage dam for farmland construction based on GIS use in other application scenes, its specific implementation process is similar to above-described embodiment, repeats no more here.

Each sequence number in above-described embodiment, just to describing, does not represent the sequencing in the assembling of each parts or use procedure.

The foregoing is only embodiments of the invention, not in order to limit the present invention, within the spirit and principles in the present invention all, any amendment of doing, equivalent replacement, improvement etc., all should be included within protection scope of the present invention.

Claims (7)

1. the silt storage dam for farmland construction based on GIS blocks silting-up evaluation method, it is characterised in that, the described silt storage dam for farmland construction based on GIS blocks silting-up evaluation method, comprising:

Obtain the GIS image comprising current region height value and comprise described the 2nd GIS image when forefoot area silt storage dam for farmland construction distribution plan, based on a described GIS Image Acquisition first grid lattice matrix, element in described first grid lattice matrix represents the height value of corresponding grid, based on described 2nd GIS Image Acquisition second gate lattice matrix, the element in described second gate lattice matrix represents the height value of corresponding silt storage dam for farmland construction;

Based on described first grid lattice matrix, it is determined that the simple and easy position data without interception network of waterways model;

From described second gate lattice matrix, obtain the position data of silt storage dam for farmland construction, in conjunction with the described simple and easy positional number without interception network of waterways model according to this and described first grid lattice matrix, the position data of described silt storage dam for farmland construction are revised, obtains the correction position data of described silt storage dam for farmland construction;

Correction position data according to described silt storage dam for farmland construction, in conjunction with described first grid lattice matrix and described second gate lattice matrix, determine the absolute sea level elevation value in described silt storage dam for farmland construction, based on described absolute sea level elevation value, described silt storage dam for farmland construction is carried out two-way expansion, obtain the expansion silt storage dam for farmland construction being made up of some amount dam point;

In described first grid lattice matrix, based on the flow direction at some place, described dam, it is determined that the storage capacity of described expansion silt storage dam for farmland construction;

According to described storage capacity, it is determined that described expansion silt storage dam for farmland construction block silting-up, and described silting-up of blocking is checked.

2. the silt storage dam for farmland construction based on GIS according to claim 1 blocks silting-up evaluation method, it is characterised in that, based on described first grid lattice matrix, it is determined that the simple and easy position data without interception network of waterways model, comprising:

Calculate the gradient value of eight nearest grids of sample grid and described sample grid in described first grid lattice matrix, choose the direction corresponding with maximum gradient value as the current direction corresponding with described sample grid;

Carry out unit water catchment area accumulation along described current direction, obtain water catchment area data;

Choosing the target grid being greater than the first predetermined threshold value in described water catchment area data, the position data that described target grid is corresponding are the simple and easy position data without interception network of waterways model.

3. the silt storage dam for farmland construction based on GIS according to claim 1 blocks silting-up evaluation method, it is characterized in that, the position data of silt storage dam for farmland construction are obtained from described second gate lattice matrix, in conjunction with the described simple and easy positional number without interception network of waterways model according to this and described first grid lattice matrix, the position data of described silt storage dam for farmland construction are revised, obtain the correction position data of described silt storage dam for farmland construction, comprising:

The position data of silt storage dam for farmland construction are determined from described second gate lattice matrix;

According to the described simple and easy model position data without the interception network of waterways, judge described described simple and easy without interception network of waterways place, whether there is silt storage dam for farmland construction;

If there is not silt storage dam for farmland construction at described simple and easy nothing interception network of waterways place, then position data according to described silt storage dam for farmland construction determine the target grid corresponding with described silt storage dam for farmland construction in described first grid lattice matrix, choose and eight the relevant grids nearest to described target grid have the replacement grid of the maximum relevant grid of unit water catchment area as described silt storage dam for farmland construction, using the correction position data of described replacement grid mapped locations data as described silt storage dam for farmland construction.

4. the silt storage dam for farmland construction based on GIS according to claim 1 blocks silting-up evaluation method, it is characterized in that, correction position data according to described silt storage dam for farmland construction, in conjunction with described first grid lattice matrix and described second gate lattice matrix, determine the absolute sea level elevation value in described silt storage dam for farmland construction, based on described absolute sea level elevation value, described silt storage dam for farmland construction is carried out two-way expansion, obtains the expansion silt storage dam for farmland construction being made up of some amount dam point, comprising:

Described first grid lattice matrix is determined first height value corresponding with the correction position data of described silt storage dam for farmland construction, described second gate lattice matrix extracts two height value corresponding with described silt storage dam for farmland construction, according to described first height value and described 2nd height value, obtain the absolute sea level elevation value of described silt storage dam for farmland construction;

In described first grid lattice matrix, choose the neighbour's grid being positioned at the sea level elevation on the left of the corresponding grid of described silt storage dam for farmland construction correction position data higher than described absolute sea level elevation value, using described neighbour's grid as left expansion grid, described left expansion grid and the whole grids on described silt storage dam for farmland construction correction position data corresponding grid line are extended for the left dam point of described silt storage dam for farmland construction;

In described first grid lattice matrix, choose the neighbour's grid being positioned at the sea level elevation on the right side of the corresponding grid of described silt storage dam for farmland construction correction position data higher than described absolute sea level elevation value, using described neighbour's grid as right expansion grid, described right expansion grid and the whole grids on described silt storage dam for farmland construction correction position data corresponding grid line are extended for the right dam point of described silt storage dam for farmland construction;

According to described left dam point and described right dam point, obtain the expansion silt storage dam for farmland construction being made up of some amount dam point after two-way expansion.

5. the silt storage dam for farmland construction based on GIS according to claim 1 blocks silting-up evaluation method, it is characterised in that, in described first grid lattice matrix, based on the flow direction at some place, described dam, it is determined that the storage capacity of described expansion silt storage dam for farmland construction, comprising:

From described expansion silt storage dam for farmland construction, choose sample dam point, described first grid lattice matrix is determined the sample grid corresponding with described sample dam point, obtain eight nearest with described sample grid and associate the flow direction in grid;

If the described flow direction is for pointing to described sample dam point, determine that the height value that described association grid is corresponding is less than described absolute sea level elevation value simultaneously, calculate the single-point volume of described sample dam point, described single-point volume is added in the cumulative storage capacity of described expansion silt storage dam for farmland construction, and described sample dam point is defined as reference point;

Described reference point is pointed to when the flow direction that there are eight grids around the corresponding grid of described reference point has a target to flow to, when the sea level elevation of the corresponding grid of the described target flow direction is not less than described absolute sea level elevation value simultaneously, stop storage capacity calculating, using storage capacity as described expansion silt storage dam for farmland construction of the described cumulative storage capacity that gets before.

6. the silt storage dam for farmland construction based on GIS according to claim 1 blocks silting-up evaluation method, it is characterised in that, according to described storage capacity, it is determined that described expansion silt storage dam for farmland construction block silting-up, comprising:

Based on drainage area Vero, determined the effective holdingcapacity El of described expansion silt storage dam for farmland construction by formula one₀,

El₀=Vero �� (1-Def), formula one,

Wherein, Def is ground, dam interception coefficient, namely often collects to come in 100 materials, it is possible to retain the material ratio in ground, dam;

Effective holdingcapacity El according to described expansion silt storage dam for farmland construction₀In conjunction with formula two, it is determined that the amount of the retaining Ed of single described expansion silt storage dam for farmland construction_i,

Formula two,

Wherein, Vmax is the storage capacity of described silt storage dam for farmland construction;

By the amount of the retaining Ed of described single expansion silt storage dam for farmland construction_iCumulative summation, blocks silting-up Edt in conjunction with what formula three obtained described expansion silt storage dam for farmland construction,

Formula three.

7. the silt storage dam for farmland construction based on GIS according to claim 1 blocks silting-up evaluation method, it is characterised in that, described silting-up of blocking is checked, comprising:

When forefoot area is provided with the number of dropouts El in described silt storage dam for farmland construction region described in obtaining_iAnd the number of dropouts in described silt storage dam for farmland construction region is not setDescribed total number of dropouts Elt when forefoot area is obtained according to formula four,

Formula four;

Block silting-up Edt according to described total number of dropouts Elt in conjunction with described expansion silt storage dam for farmland construction, determine the described actual loss total amount Lt' when forefoot area by formula five,

Lt'=Edt+Elt, formula five;

Work as forefoot area for described, determine the theoretical loss total amount Lt when not arranging described expansion silt storage dam for farmland construction according to formula six,

Formula six,

Wherein, E_kFor described when the erosion amount of each grid in first grid lattice matrix described in forefoot area, l is the total amount of grid in described first grid lattice matrix;

When described theoretical loss total amount Lt and described actual loss total amount Lt' approximately equal, the silting-up Edt that blocks of described expansion silt storage dam for farmland construction calculates accurately.