BOREAS Forest Cover Data Layers of the NSA in Raster Format Summary This data set was processed by BORIS staff from the original vector data of species, crown closure, cutting class, and site classification/subtype into raster files. The original polygon data were received from Linnet Graphics, the distributor of data for MNR. In the case of the species layer, the percentages of species composition were removed. This reduced the amount of information contained in the species layer of the gridded product, but it was necessary in order to make the gridded product easier to use. The original maps were produced from 1:15,840-scale aerial photography collected in 1988. The data are stored in binary, image format files. Note that the binary files of this data set on the BOREAS CD-ROMs have been compressed using the Gzip program. See section 8.2 for details. Table of Contents * 1 Data Set Overview * 2 Investigator(s) * 3 Theory of Measurements * 4 Equipment * 5 Data Acquisition Methods * 6 Observations * 7 Data Description * 8 Data Organization * 9 Data Manipulations * 10 Errors * 11 Notes * 12 Application of the Data Set * 13 Future Modifications and Plans * 14 Software * 15 Data Access * 16 Output Products and Availability * 17 References * 18 Glossary of Terms * 19 List of Acronyms * 20 Document Information 1. Data Set Overview 1.1 Data Set Identification BOREAS Forest Cover Data Layers of the NSA in Raster Format 1.2 Data Set Introduction This data set was gridded to a 30-meter pixel size from vector polygons of forest cover information. The four separate layers include species, crown closure category, cutting class, and site classification/subtype. 1.3 Objective/Purpose These data are provided as part of the BOReal Ecosystem-Armosphere Study (BOREAS) Staff Science Geographic Information System (GIS) Data Collection Program, which included the collection of pertinent map data in both hardcopy and digital form. This data set, originally provided as vector polygons with attributes, has been processed to provide raster files that can be used for modeling or for comparison purposes. It has been used by foresters and others interested in the forest resources of Manitoba. 1.4 Summary of Parameters The parameters in this raster data set include species, crown closure category, cutting class, and site classification/subtype. 1.5 Discussion As mentioned in the Summary and Section 1.2, these data were gridded from vector polygons produced by Manitoba Natural Resources (MNR) and distributed by Linnet Graphics. A full description of the data layer derivations is given in Section 9. 1.6 Related Data Sets The original vector data are available for a larger area, but not from BOREAS. Individuals interested in the original data should contact Linnet Graphics as indicated in Section 7.3. BOREAS Forest Cover Data for the Southern Study Area in Vector Form BOREAS Forest Cover Data for the Southern Study Area in Raster Form 2. Investigator(s) 2.1 Investigator(s) Name and Title BOREAS Staff 2.2 Title of Investigation BOREAS Staff Science GIS Data Collection Program 2.3 Contact Information Contact 1 ----------- David Knapp NASA/GSFC Greenbelt, MD (301) 286-1424 (301) 286-0239 (fax) David.Knapp@gsfc.nasa.gov Contact 2 ----------- Manning Tuinhoff Manitoba Natural Resources Forestry Branch Winnipeg, Manitoba Canada (204) 945-7952 3. Theory of Measurements MNR personnel collect and maintain GIS types of information for use by natural resource managers. The data from which these were derived are a part of the MNR data holdings. 4. Equipment 4.1 Sensor/Instrument Description Linnet Graphics is the distributor of the vector data for MNR. The original data were digitized from maps at a scale of 1:15,840. These maps were produced from aerial photography collected in 1988. The original vector data were acquired as ARC/INFO vector coverages in ARC/INFO export format. No specific information other than the scale of the resulting photography is known about the aircraft flights or the equipment that was used to collect the aerial photography. 4.1.1 Collection Environment Unknown. 4.1.2 Source/Platform Unknown. 4.1.3 Source/Platform Mission Objectives Unknown. 4.1.4 Key Variables The key variables in this raster data set include species, crown closure category, cutting class, and site classification/subtype. 4.1.5 Principles of Operation Unknown. 4.1.6 Sensor/Instrument Measurement Geometry Unknown. 4.1.7 Manufacturer of Sensor/Instrument Unknown. 4.2 Calibration 4.2.1 Specifications Unknown. 4.2.1.1 Tolerance Unknown. 4.2.2 Frequency of Calibration Unknown. 4.2.3 Other Calibration Information Unknown. 5. Data Acquisition Methods The original data were digitized from 1:15,840-scale maps that were produced from aerial photography collected in 1988. 6. Observations Not applicable. 6.1 Data Notes None. 6.2 Field Notes Field survey or data verification notes may be available through MNR but are not known in detail by BOREAS Information System (BORIS) personnel. 7. Data Description 7.1 Spatial Characteristics 7.1.1 Spatial Coverage These data cover an area of the Northern Study Area (NSA) Modeling Sub-Area (MSA) that in turn covers most of the tower sites. The outside corners of the corner image pixels are as follows: BOREAS BOREAS NAD83 Corner X (km) Y (km) Longitude Latitude ---------------------------------------------------------- Northwest 759.000 632.010 98.732W 56.074N Northeast 816.000 632.010 97.832W 55.981N Southwest 759.000 602.010 98.816W 55.809N Southeast 816.000 602.010 97.922W 55.717N 7.1.2 Spatial Coverage Map Not available. 7.1.3 Spatial Resolution These data were gridded to a cell size of 30 meters. 7.1.4 Projection The area mapped is projected in the ellipsoidal version of the Albers Equal Area Conic (AEAC) projection. The projection has the following parameters: Datum: North American Datum 1983 (NAD83) Ellipsoid: GRS80 or WGS84 Origin: 111.0000W degrees 51.0000N Standard Parallels: 520 30' 00"N 580 30' 00"N Units of Measure: kilometers 7.1.5 Grid Description The data are gridded in 30-meter intervals based on the ellipsoidal version of the AEAC projection with standard parallels of 52° 30' N, 58° 30' N and a southwest origin of 51° N, 111° W. 7.2 Temporal Characteristics 7.2.1 Temporal Coverage The publication dates of the hardcopy version of the maps from which these data were derived range from 1991 to 1992. BORIS acquired the data in 1994; the forest cover layers have not yet had any inventory updates. 7.2.2 Temporal Coverage Map Not available. 7.2.3 Temporal Resolution As noted, the original maps were produced from 1:15,840-scale aerial photography collected in 1988. Although hardcopy versions of these maps were published in 1990 and 1991, BORIS Staff is not aware of any updates since 1988. 7.3 Data Characteristics 7.3.1 Parameter/Variable Species Category Cutting Class Crown Closure Site Class 7.3.2 Variable Description/Definition Species Category - The category of vegetative species covering the given area as derived by BORIS personnel. SPECIES CATEGORY VALUES Pixel Value Cover Type ----------- ----------------- 11 Jack Pine (JP) 12 Black Spruce (BS) 13 Tamarack Larch (TL) 14 White Spruce (WS) 15 JP/BS 16 BS/JP 17 BS/TL 18 TL/BS 19 BS/WS 20 JP/WS 21 WS/BS 22 WS/JP 23 BS/JP/TL 24 JP/BS/TL 25 BS/WS/JP 26 BS/TL/JP 31 Trembling Aspen (TA) 33 White Birch (WB) 41 JP/TA 42 BS/TA 43 WS/TA 44 BS/WB 45 BS/JP/TA 46 JP/BS/TA 47 BS/WS/TA 48 BS/TL/TA 49 JP/BS/WB 50 BS/JP/WB 51 WS/JP/TA 52 WS/BS/TA 53 JP/WS/TA 54 BS/JP/TL/TA 55 BS/BA 61 TA/JP 62 TA/BS 63 TA/WS 64 WB/BS 65 TA/JP/BS 66 TA/BS/JP 67 TA/JP/WS 68 TA/WS/JP 69 TA/BS/TL 70 TA/WS/BS 71 TA/WB/JP/BS 72 BA/BS 73 Willow 101 treed muskeg 102 treed rock 103 clear muskeg 105 brushland 107 clearing 109 nonproductive burn-over 121 flooded land 122 water 133 disturbance - cut-over 134 disturbance - burn-over 135 experimental area 136 gravel pits/mines 137 marsh 138 town 139 roads 140 hayland 141 drainage ditch 142 precipitous slopes/fragile 143 small islands 144 transmission/pipelines Species Symbol --------------------------- Ash AS Basswood B Balsam Poplar BA Balsam Fir BF Bur Oak BO Black Spruce BS Eastern Cottonwood CO White Elm E Eastern Cedar EC Hackberry HB Hop Hornbeam HH Jack Pine JP Large Tooth Aspen LA Manitoba Maple MM Red Pine RP Scots Pine SP Trembling Aspen TA Tamarack Larch TL Willow W White Birch WB White Pine WP White Spruce WS Cutting Class - Cutting class is based on size, vigor, state of development, and maturity of a stand for harvesting purposes with designations such as ‘Unproductive,' ‘Not restocked,' ‘Immature,' and ‘Mature.' CUTTING CLASS VALUES PIXEL VALUE DESCRIPTION ----- -------------------------------------------------- 0 No original data over the area. 1 Unproductive stands. No cutting class given. 2 Forest land not restocked following fire, cutting, windfall, or other major disturbances (hence, potentially productive land). Some reproduction or scattered residual trees (with net merchantable volume less than 20 cubic meters per hectare) may be present. 3 Stands that have been restocked either naturally or artificially. Scattered residual trees may be present as in cutting class 0. To be in cutting class 3 the average height of the stand must be less than 3 meters (3 m). 4 Advanced young growth of post size, with some merchantable volume. The average height of the stand must be over 3 meters in order to be in this cutting class. 5 Immature stands with merchantable volume growing at or near their maximum rate, which definitely should not be cut. The average height of the stand should be over 10 meters and the average diameter should be over 9.0 centimeters (9.0 cm) at Diameter at Breast Height (DBH) (1.3 m). 6 Mature stands that may be cut because they have reached rotation age (+/- 10 years on site 1 or +/- 20 years on site 2. 7 Over mature stands, which should be given priority in cutting. Crown Closure Category - The category of crown closure specified in the original data set. CROWN CLOSURE CATEGORY VALUES Crown closure was estimated from the photography by the photointerpreter. Five classes were recognized and entered onto the stand description sheet for each township as part of the photointerpreted type aggregate. Changes of this estimate can be made only under exceptional circumstances. PIXEL VALUE DESCRIPTION ----- ------------------------------ 0 No original data over the area. 1 Unproductive stand. No Crown Closure given. 2 Applies to Cutting Class 0 stands only. 3 15%-30% crown closure. 4 31%-50% crown closure. 5 51%-70% crown closure. 6 71% and over. Site Class - The type of site on which the forest is growing. SITE CLASS VALUES Note that the site class descriptions that follow were taken from page 16 of “Natural Resources Manitoba - Forest Instruction Manual," Feb. 1996, which was supplied to BORIS staff with the original vector data. However, the manual indicates that the site classification is applicable only to the Interlake Section of Manitoba, and the BOREAS NSA near Thompson is not included geographically in the Interlake Section. Therefore, it is not clear if the provided descriptions are totally applicable. The land types and associated indicator plants are described for each moisture regime described in a table on page 16 of “Natural Resources Manitoba - Forest Instruction Manual," Feb. 1996. The moisture regime in return denotes the site class for each tree species. Because height, growth, and stand density are reflections of site, these factors should be considered when evaluating the growth of timber types. A site class was assigned to each subtype on the basis of its major species. In general terms, site class 1 is associated with moist, very moist, and wet moisture regimes, regardless of the dominant tree species. Site class 2 is associated with the saturated moisture regime when black spruce or tamarack is the dominant species. Site class 2 is also associated with the dry moisture regime when jack pine or trembling aspen is the dominant species. Site class 3 is generally associated with various tree species in the arid or dry moisture regime. Refer to the table on page 16 of “Natural Resources Manitoba - Forest Instruction Manual," Feb. 1996, for more information on this layer. Although the plants generally reflect the moisture regime of the area, they become important site indicators only when they occur in abundance throughout the entire type. Localized elevations and depressions in the timber stand can reflect entirely different plant indicators than those throughout most of the type. Mineral and nutrients strongly influence tree growth but may not affect the presence of minor vegetation. Most of the soil in the Interlake area of Manitoba consists of strongly calcareous till. Although this high calcareous content does not affect the growth of indicators of class 1 jack pine sites, it seriously inhibits the growth of jack pine. On the other hand, Sphagnum ssp. do not tolerate high lime conditions. For this reason, feather moss rather than sphagnum is found on much of the deep organic terrain in the Interlake section. Because most of the indicator plants grow over a range of moisture regimes, they generally become important only when they occur in abundance and when a variety of plants are present. In isolated cases, however, the mere presence of a certain indicator plant throughout the type can denote site class. A good example of this is when bunchberry or twinflower occurs in association with jack pine. These plants do not occur on dry moisture regimes and therefore denote site class 1. 7.3.3 Unit of Measurement Species Category - Coded but unitless value. Cutting Class - Coded but unitless value. Crown Closure - Coded but unitless value. Site Class - Coded but unitless value. 7.3.4 Data Source The original data were acquired in ARC/INFO format from: Linnet Graphics International, Inc. 600-191 Broadway Avenue Winnipeg, Manitoba, Canada R3C 3T8 7.3.5 Data Range Species Category - 11 to 144 Cutting Class - 0 to 7 Crown Closure - 0 to 6 Site Class - 1 to 9 7.4 Sample Data Record Not applicable. 8. Data Organization 8.1 Data Granularity The smallest amount of obtainable data is the entire data set containing the four raster layers and other supporting files. 8.2 Data Format(s) 8.2.1 Uncompressed Data Files The data product consists of five total files. The first file is an American Standard Code for Information Interchange (ASCII) header file that describes the product. Files 2 through 5 contain the binary raster data layers. Each file (raster layer) contains 1,900 8-bit (1-byte) values in each of 1,000 lines. The following is a list of the data set files: Record Number of File Description Size (Bytes) Records Bytes/Pixel ------------------------------------------------------------------------ 1 Header File 80 N/A 2 SPECIES COVER 1900 1000 1 3 CUTTING CLASS 1900 1000 1 4 CROWN CLOSURE 1900 1000 1 5 SITE CLASS 1900 1000 1 8.2.2 Compressed CD-ROM Files On the BOREAS CD-ROMs, file 1 listed above is stored as ASCII text; however, files 2 through 5 have been compressed with the Gzip compression program (file name *.gz). These data have been compressed using gzip version 1.2.4 and the high compression (-9) option (Copyright (C) 1992-1993 Jean-loup Gailly). Gzip (GNU zip) uses the Lempel-Ziv algorithm (Welch, 1994) used in the zip and PKZIP programs. The compressed files may be uncompressed using gzip (-d option) or gunzip. Gzip is available from many websites (for example, ftp site prep.ai.mit.edu/pub/gnu/gzip-*.*) for a variety of operating systems in both executable and source code form. Versions of the decompression software for various systems are included on the CD-ROMs. 9. Data Manipulations The original polygon data were digitized from 1:15,840-scale forest cover maps by MNR or by an organization appointed by MNR. The important attributes that were associated with each polygon are as follows: COVERTYPE SPECIES LAND-ID The following data layers were extracted and gridded from the above attributes: SPECIES COVER CROWN CLOSURE CUTTING CLASS SITE CLASS/SUBTYPE The SPECIES COVER layer was produced based on information from the SPECIES attribute. CROWN CLOSURE, CUTTING CLASS, and SITE CLASS were extracted from the original COVERTYPE attribute. The original COVERTYPE attribute consists of a 5 digit code. The third, fourth, and fifth digits of this code indicate the site class, cutting class, and crown closure, respectively. 9.1 Formulae 9.1.1 Derivation Techniques and Algorithms For the SPECIES layer, the species attribute string had to be modified for each polygon. In general, the species attributes were labeled as dominant species and percent followed by codominant species and percent. For example, a polygon with a species attribute of BS6JP4 indicated 60% black spruce, 40% jack pine. Similarly, BS7JP3 indicated 70% black spruce, 30% jack pine. In creating the raster species cover layer, the percentages were removed to change initial polygons listed with black spruce first followed by jack pine to BS/JP. Polygons labeled as BS5JP5 or JP5BS5 retained their original species label order. Any resultant polygons that were labeled as BS/JP were assigned a value of 16. In this same manner, all polygons were assigned numeric values thatwere used as pixel values in the gridded product. The crown closure, cutting class, and site class parameters were only renumbered from their original values. 9.2 Data Processing Sequence 9.2.1 Processing Steps The following processing sequence was used to grid each of the four layers: 1) Edit vectors as needed to create gridded layers. 2) Reproject vectors from Universal Transverse Mercator (UTM) to AEAC projection 3) Grid vector coverages. 4) Combine gridded townships to make one large gridded layer. 5) Write gridded layers to tape. 6) Copy the ASCII and compress the binary files for release on CD-ROM. 9.2.2 Processing Changes None. 9.3 Calculations 9.3.1 Special Corrections/Adjustments None. 9.3.2 Calculated Variables None. 9.4 Graphs and Plots None. 10. Errors 10.1 Sources of Error A source of error in the original data set could be digitizing error. The possibility of coding errors in the attributes also exists. The value of an attribute could have been keyed in incorrectly. 10.2 Quality Assessment 10.2.1 Data Validation by Source Unknown. 10.2.2 Confidence Level/Accuracy Judgment Although the gridding procedure itself is highly accurate there is some question as to the accuracy of the original data. Therefore, caution should be used when inferring information from this data set. 10.2.3 Measurement Error for Parameters Unknown. 10.2.4 Additional Quality Assessments Not applicable. 10.2.5 Data Verification by Data Center Each gridded image was visually checked by BORIS personnel to ensure that the gridding procedure assigned a digital number (DN) to each attribute value and that the resultant images seemed reasonable. 11. Notes 11.1 Limitations of the Data BORIS Staff acquired these data in 1994; areas subjected to logging activity or other disturbance, such as fire, would appear much different today as compared to the forest cover data. 11.2 Known Problems with the Data At least one polygon in the original data was incorrectly coded. The SPECIES was indicated as 80% Balsam Poplar and 20% Balsam Poplar (coded BA8BA2). This was an obvious coding error in the original data. There were also a few polygons that did not have any code at all. In these cases, a code was added if it existed in the hardcopy version of the product: otherwise, it was left as a "no data" area. 11.3 Usage Guidance The SPECIES layer can be used to determine the dominant species or the presence of a species in an area. The CROWN CLOSURE layer can be used to estimate tree density. The CUTTING CLASS layer can be used to estimate stand age. Before uncompressing the Gzip files on CD-ROM, be sure that you have enough disk space to hold the uncompressed data files. Then use the appropriate decompression program provided on the CD-ROM for your specific system. 11.4 Other Relevant Information MNR personnel are constantly updating their data. Contact Linnet Graphics International, Inc., for more recent data. 12. Application of the Data Set This data set would provide good reference information for assessing spectral image data classification techniques over the area and as an initial baseline data set for analyzing land cover and vegetation change. 13. Future Modifications and Plans None. 14. Software 14.1 Software Description The data manipulation capabilities in the ARC/INFO software package (Version 7) were used to reproject the vector data prior to gridding. Questions about the software should be directed to: Environmental Systems Research Institute, Inc. 380 New York Street Redlands, CA 92373-8100 Gzip (GNU zip) uses the Lempel-Ziv algorithm (Welch, 1994) used in the zip and PKZIP commands. 14.2 Software Access ARC/INFO is a commercial package; contact Environmental Systems Research Institute, Inc. (ESRI) for details. Gzip is available from many websites across the net (for example) ftp site prep.ai.mit.edu/pub/gnu/gzip-*.*) for a variety of operating systems in both executable and source code form. Versions of the decompression software for various systems are included on the CD-ROMs. 15. Data Access 15.1 Contact Information Ms. Beth McCowan BOREAS Data Manager NASA/GSFC Greenbelt, MD (301) 286-4005 (301) 286-0239 (fax) beth@ltpmail.gsfc.nasa.gov 15.2 Data Center Identification See Section 15.1. 15.3 Procedures for Obtaining Data Users may place requests by telephone, electronic mail, or fax. 15.4 Data Center Status/Plans The NSA forest cover data are available from the Earth Observing System Data and Information System (EOSDIS) Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC). The BOREAS contact at ORNL is: ORNL DAAC User Services Oak Ridge National Laboratory (865) 241-3952 ornldaac@ornl.gov ornl@eos.nasa.gov 16. Output Products and Availability 16.1 Tape Products These data can be made available on 1600 or 6250 Bytes Per Inch (BPI) 9-track, 8-mm, or Digital Archive Tape (DAT) tapes. 16.2 Film Products None. 16.3 Other Products These data are available on the BOREAS CD-ROM series. 17. References 17.1 Platform/Sensor/Instrument/Data Processing Documentation Natural Resources Manitoba - Forest Instruction Manual, Feb. 1996. ARC/INFO User's Guide (Version 7) 1994. Redlands, CA. Welch, T.A. 1984, A Technique for High Performance Data Compression, IEEE Computer, Vol. 17, No. 6, pp. 8 - 19. 17.2 Journal Articles and Study Reports Sellers, P.and F. Hall. 1994. Boreal Ecosystem-Atmosphere Study: Experiment Plan. Version 1994-3.0, NASA BOREAS Report (EXPLAN 94). Sellers, P.and F. Hall. 1996. Boreal Ecosystem-Atmosphere Study: Experiment Plan. Version 1996-2.0, NASA BOREAS Report (EXPLAN 96). Sellers, P., F. Hall and K.F. Huemmrich. 1996. Boreal Ecosystem-Atmosphere Study: 1994 Operations. NASA BOREAS Report (OPSDOC 94). Sellers, P., F. Hall and K.F. Huemmrich. 1997. Boreal Ecosystem-Atmosphere Study: 1996 Operations. NASA BOREAS Report (OPSDOC 96). Sellers, P., F. Hall, H. Margolis, B. Kelly, D. Baldocchi, G. den Hartog, J. Cihlar, M.G. Ryan, B. Goodison, P. Crill, K.J. Ranson, D. Lettenmaier, and D.E. Wickland. 1995. The boreal ecosystem-atmosphere study (BOREAS): an overview and earlyresults from the 1994 field year. Bulletin of the American Meteorological Society. 76(9):1549-1577. Sellers, P.and F. Hall. 1997. BOREAS Overview Paper. JGR Special Issue (in press). 17.3 Archive/DBMS Usage Documentation None. 18. Glossary of Terms None. 19. List of Acronyms AEAC - Albers Equal-Area Conic ASCII - American Standard Code for Information Interchange BOREAS - BOReal Ecosystem-Atmosphere Study BORIS - BOREAS Information System BPI - Bytes per inch CCRS - Canadian Centre for Remote Sensing CCT - Computer Compatible Tape CD-ROM - Compact Disk-Read-Only Memory DAAC - Distributed Active Archive Center DAT - Digital Archive Tape DN - Digital Number EOS - Earth Observing System EOSDIS - EOS Data and Information System ESRI - Environmental Systems Research Institute, Inc. GIS - Geographic Information System GSFC - Goddard Space Flight Center MSA - Modeling Sub-Area NAD83 - North American Datum 1983 MNR - Manitoba Natural Resources NASA - National Aeronautics and Space Administration NSA - Northern Study Area OA - Old Aspen OBS - Old Black Spruce OJP - Old Jack Pine ORNL - Oak Ridge National Laboratory PANP - Prince Albert National Park SSA - Southern Study Area UTM - Universal Transverse Mercator URL - Uniform Resource Locator (a World Wide Web address) YJP - Young Jack Pine 20. Document Information 20.1 Document Revision Dates Written: 01-Aug-1994 Last Updated: 30-Jul-1998 20.2 Document Review Dates BORIS Review: 20-Jun-1997 Science Review: 20.3 Document ID 20.4 Citation The original data were provided by MNR. The vector data were processed and gridded by BORIS staff. The contribution of the vector data by MNR and the processing of the data by BORIS staff are greatly appreciated. 20.5 Document Curator 20.6 Document URL Keywords GIS FOREST COVER SPECIES CUTTING CLASS CROWN CLOSURE SITE CLASS NSA_Forest_Cover.doc 08/18/98