WEPP GIS Support Programs

Transcription

1 WEPP GIS Support Programs This describes how to use the various WEPP GIS programs along with TOPAZ programs to create WEPP input files. Other GIS alternatives to GeoWEPP could be developed using these programs to do the TOPAZ and WEPP processing. The TOPAZ programs are from USDA ARS El Reno. The UTMS.EXE conversion program is from USGS. The custom programs demanly, convdem, topwepp4, topwepp2 and climport are from USDA ARS NSERL. GeoWEPP is from SUNY Buffalo, it makes use of the programs described below. The TOPAZ documentation is available online (although sometimes hard to find). It is not necessary to know the detail file formats because the programs take care of setting up the files. The documentation is useful for the other options that could be used and other files that are created by TOPAZ but not used in WEPP processing. TOPAZ Overview Manual2.pdf TOPAZ User Guide Manual2.pdf The basic steps for making a WEPP watershed run with TOPAZ and a GIS are: 1. Create a channel network from a DEM area 2. Select a watershed output point on the channel network 3. Delineate a watershed from the outlet point selected 4. Find the nearest CLIGEN climate station to the watershed outlet 5. Run a WEPP watershed and flowpath simulation for the defined area 6. Change landuse, soils and make other WEPP runs of the area. Pass 1: Channel Delineation From a DEM area the channel network is defined with the user supplied CSA and MSCL input values. This step requires the following pieces of information: 1. DEM for area of interest in UTM projection 2. Critical Source Area (CSA) in ha 3. Minimum Source Channel Length (MSCL) in meters 4. Template file dnmcnt.txt, rasfor.inp 5. TOPAZ programs dednm, rasfor (FORTRAN)

2 6. TOPAZ input preparation program demanly (C++) The DEM should be stored in a file named tmpdem1.dat as an ASCII grid file in the UTM projection. The CSA and MSCL values are stored in a file called csa.inp. The csa.inp file should just have 3 items on one line: The first parameter can be a constant 1, the second parameter is the CSA and the third the MSCL. Next, run the demanly program which will prepare the input files for TOPAZ. The program does not take any parameters, it reads input from tmpdem1.dat, dnmcnt.txt and csa.inp and creates output files dednm.inp and dnmcnt.inp. After running the demanly program there will be two files created: dednm.inp and dnmcnt.inp These are input files for the TOPAZ program dednm. Dednm.inp is the DEM reformatted so there is only one value per line. The dnmcnt.inp file is the control file for the TOPAZ dednm program that has information for the rows and columns along with the CSA and MSCL parameter. Next, run the TOPAZ program dednm which will read the input files dednm.inp and dnmcnt.inp. This will produce a lot of output files. Next, run the TOPAZ program rasfor which will format the TOPAZ output into readable raster files. This has program options specified in the file rasfor.inp which it reads as input. The output file NETFUL.ARC is the channel grid, cells values of 1 indicate a channel. This is an ASCII grid file that can be loaded into a GIS to display. Pass 2: Watershed Delineation The user picks a location on a channel cell from the NETFUL.ARC grid that defines the outlet for the watershed. The watershed subcatchments and other information about the watershed is generated by TOPAZ programs. 1. This step requires the following pieces of information: 2. DEM for area of interest in UTM projection 3. Critical Source Area (CSA) in ha 4. Minimum Source Channel Length (MSCL) in meters 5. Channel network file 6. Outlet point The DEM should be stored in a file named tmpdem1.dat as an ASCII grid file in the UTM projection. The CSA and MSCL values are stored in a file called csa.inp. The csa.inp file should just have 3 items on one line:

3 The first parameter can be a constant 1, the second parameter is the CSA and the third the MSCL. The outlet point should be stored in the file tmpdem1.pnt. It is one line that has the word Point: followed by the UTM coordinates: Point: If the top of the DEM header looks like the following, the above would be a valid outlet point. ncols 707 nrows 463 xllcorner yllcorner cellsize 30 NODATA_value Next, run the convdem program which will prepare the input files for TOPAZ. The program does not take any parameters, it reads input from tmpdem1.dat, dnmcnt.txt, csa.inp and tmpdem1.pnt files and creates output files dednm.inp and dnmcnt.inp. Next, run the TOPAZ program dednm which will read the input files dednm.inp and dnmcnt.inp. This will produce a lot of output files. It will also has a prompt for user input which can be worked around by starting the program like this: echo 1./dednm Next, run the TOPAZ program raspro. Next, run the TOPAZ program rasfor which will format the TOPAZ output into readable raster files. This has program options specified in the file rasfor.inp which it reads as input. The output file SUBWTA.ARC is the subctachment ASCII grid file, BOUND.ARC is the watershed boundary ASCII grid file that can loaded into a GIS program. Climate Selection The first step is to convert the outlet point from UTM to latitude+longitude so that the CLIGEN database can be searched to find the nearest station. This is done with the utms.exe program, the program and documentation for utms can be found at the following site: To run this without the interactive mode create a response file such as: 2 1 n bluebook.f81 bluebook.f80 y

4 bluebook.sum n And then run as utms.exe < utms.inp The bluebook.f81 file is the input and has a format like the following: *81* Point: The bluebook.f80 and bluebook.sum are output files. The format for input files is described in the link above. The file bluebook.sum is what is needed for cligen searching. After utms.exe has been run start the climport program: Figure 1 Climport program interface Here the user can use the selected cligen station or build a new climate file from another station. Pass 3: WEPP Simulation After the watershed delineation is complete and the climate selected the next step is to run a WEPP simulation. The program that controls this is called topwepp2.exe (on the web based GIS this is called prepwepp). The main task of the program is to translate between TOPAZ watershed files to WEPP model input files. This also relies on the WEPP install files and databases. In addition to the TOPAZ files and WEPP install files a file named cmd2.txt is read which defines settings for the watershed run. The following is an example cmd2.txt file: Root = C:\Program Files\USDA-ARS\WEPP\ climate = "Indiana\WEST LAFAYETTE 6 NW IN.cli" management = "grass.rot" soil = "KEITH.sol" channel = "DITCH" channelwidth = 3 years = 2 SoilLossGrid

5 SedimentGrid RunoffGrid RunWatershed RunFlowpaths ManagementGrid = "landcov.asc" SoilGrid = "soilsmap.asc" end of file

6 The following is a list of all the commands that may be included in the cmd2.txt file: Root= c:\wepp\ DebugAndRun =Y SaveDOSFiles EnableOptions Debug=Y Climate = test.cli Soil[id] = test.sol Management[id] = test.rot Channel[id] = test MangementGrid = management.asc Management = test.rot SoilGrid = soils.asc Soil = test.sol Years=10 RunFlowpaths RunWatershed FilterDailyOutput WaterBalanceOutput ReturnPeriod Location of WEPP install More outputs for debugging, includes run. For debugging, save model files. Allow more detailed options to be displayed in the topwepp program. Don t do a run but create files. Name of the WEPP climate file in quotes. Directory is relative to the WEPP install cligen directory, unless the full path is used. Name of the soil file to use for a specific hillslope or channel, the id is the TOPAZ id. This will override the default soil setting and the soil grid definitions. Name of the management rotation file to use for a specific hillslope or channel, the id is the TOPAZ id. This will override the default management and the management grid definitions. Name of the channel parameter set to use for a specific channel. The name is the keyword part of the channel database (short name). The id is the TOPAZ id for the channel element. This overrides settings read from channels.txt ASCII Grid file of the same extent as the DEM that holds id s of different managements. The id s are resolved using two other files: landusedb.txt and landcov.txt Name of the management rotation to use for the whole watershed. Either the Mangement keyword or ManagementGrid keyword should be present, but not both. ASCII grid file of the same extent as the DEM that holds id s of different soils. The id s are resolved using two other files: soilsdb.txt and soilsmap_id.txt Name of the soil file to use for the whole watershed. Either the Soil keyword or SoilGrid keywordshould be present but not both. Number of years for simulation Run flowpath simulations Run watershed simulations Saves daily hillslope runoff, soil loss Set WEPP flag to output watershed water balance file. Output a file return_periods.txt that are the return periods for the watershed run. The topwepp2 program will display the following window, the settings are from the cmd2.txt file. Options can be changed before making the WEPP runs.

7 Figure 2Topwepp2 program interface Landcov.txt This file gives symbolic names for the different ID s in the management grid file. One option is to use the USGS landcover classifications and add custom classes: 11 Open Water 12 Perennial Icd/Snow 21 Low Density Residential 22 High Density Residential 23 Commercial/Industrial/Transportation 31 Bare Rock/Sand/Clay 32 Quarries/Strip Mines/Gravel Pits 33 Transitional 41 Deciduous Forest 42 Evergreen Forest 43 Mixed Forest 51 Shrubland 61 Orchards/Vineyards/Other 71 Grasslands/Herbaceous 81 Pasture/Hay 82 Row Crops 83 Small Grains 84 Fallow 85 Urban/Recreational Grasses 91 Woody Wetlands 92 Emergent Herbaceous Wetlands 1 grass 0 No Data 2 Low Burn Severity 3 High Burn Severity 4 Unburned 5 Moderate Burn Severity

8 The names can be used to display legend information. This file is only needed if a management grid is specified in cmd2.txt. Landusedb.txt The landuse.db file makes an association between a classification and a WEPP management rotation file that will be used to simulate that landuse. It is a text file that has a character between the classification and the WEPP file name: Open Water grass.rot Perennial Icd/Snow GeoWEPP/grass.rot Low Density Residential GeoWEPP/grass.rot High Density Residential GeoWepp/grass.rot Commercial/Industrial/Transportation GeoWEPP/grass.rot Bare Rock/Sand/Clay GeoWEPP/grass.rot Quarries/Strip Mines/Gravel Pits GeoWEPP/grass.rot Transitional GeoWEPP/grass.rot Deciduous Forest GeoWEPP/Tree-20 yr old forest.rot Evergreen Forest GeoWEPP/Tree-20 yr old forest.rot Mixed Forest GeoWEPP/Tree-20 yr old forest.rot Shrubland GeoWEPP/28% cover-short grass prarie.rot Orchards/Vineyards/Other GeoWEPP/grass.rot Grasslands/Herbaceous GeoWEPP/Mountain Big Sagebrush.rot Pasture/Hay GeoWEPP/alfalfa with cuttings.rot Row Crops GeoWEPP/corn,soybean-fall mulch till.rot Small Grains GeoWEPP/winter wheat, Conventional till.rot Fallow GeoWEPP/fallow tilled.rot Urban/Recreational Grasses GeoWEPP/grass.rot Woody Wetlands GeoWEPP/Mountain Big Sagebrush.rot Emergent Herbaceous Wetlands GeoWEPP/grass.rot grass grass.rot No Data GeoWEPP/grass.rot Low Burn Severity GeoWEPP/90% cover-low severity burn.rot High Burn Severity GeoWEPP/25% cover-high severity burn.rot Unburned GeoWEPP/Tree-20 yr old forest.rot Moderate Burn Severity GeoWEPP/45% cover-moderate severity burn.rot This file is only needed if a management grid is specified in cmd2.txt. Channels.txt This file defines the channel orders, channel parameter keyword and width. Each line has 3 values: 1 OnEarth 1 2 OnEarth 2 3 OnGravel 2 4 OnGravel 3 5 OnRock 3

9 The channel parameter keyword references the parameters in the WEPP channel database file channel.db Soilsmap_id.txt This gives symbolic names for each of the id s in the soil grid file. 1 FINCASTLE 2 RODMAN 3 COHOCTAH 4 HONONEGAH This file is only needed if a soil grid is specified in cmd2.txt. Soilsdb.txt This file makes an association between the soil symbolic name and the WEPP soil file that will be used to represent that file: FINCASTLE fincastle.sol RODMAN rodman.sol COHOCTAH keith.sol HONONEGAH keith.sol The above has 2 soil types that are defaulting to the same WEPP soil file. This file is only needed if a soil grid is specified in cmd2.txt. Output Files from the WEPP Run After topwepp2 runs the WEPP simulations the following files can be displayed by the GIS interface: Summary.txt Topaz2wepp.txt Wepploss.arc Wepprunoff.arc Weppsediment.arc Ww2events.txt Ww2output.txt Events.txt Runoff.txt Weppfloss.arc Ww2.prw Brief text file of results listed by subcatchment. A listing of TOPAZ ids and the corresponding WEPP ids along with areas. Soil loss by subcatchment, the result of a watershed simulation. Runoff by subcatchment from a watershed simulation. Sediment yield by subcatchment from a watershed simulation. The watershed event output file. The main WEPP output file from the watershed run. Sediment yield from flowpath summaries (I don t think GeoWEPP uses this) Runoff from flowpath summaries (I don t think GeoWEPP uses this) Flowpath soil loss grid. The WEPP watershed project that can be loaded into WEPP Windows

10 Modifying Hillslopes This is done in GeoWEPP by the user picking a subcatchment to change the soil and/or management. The program topwepp4.exe provides an interface for choosing the new soil and management from those available in the WEPP installation directory. The topwepp4 program takes 3 arguments: Extension The type of parameter to display, valid options are: *.sol *.rot *.cli *.chn List WEPP soils in the dialog window to choose List WEPP management rotation files in the dialog List of climate files List of channel parameter sets Hillslope/channel ID The TOPAZ id of the hillslope or channel to change. Modify Set this to 1 to modify cmd2.txt (this should be the default). Example: topwepp4 *.sol 21 1 Will display the following: Figure 3Topwepp4 program interface

11 After double clicking clicking OK the cmd2.txt file will have the following line added: soil[21] = "ATHENA.sol"