ASPRS/ACSM (1994), copyright ASPRS/ACSM
One of the major difficulties in developing and implementing GIS and related technology in the field of forest resource management has been that multiple software and hardware platforms were necessary to adequately address issues. Atterbury Consultants, Inc. (ACI) has successfully integrated handheld field computers with GPS capability; timber cruising and forest inventory software; GIS and Image Processing on a common PC based system. This integration of software and hardware has been applied to practical management issues. The total system is outlined briefly to set the relationships between the various hardware and software packages. The handheld field system is described, including the hardware and software used. An overview is provided of the interface with an office based PC for forest management processing.
The paper then illustrates how the system has been used on several forest management projects with emphasis on GPS as the newest addition to the resource system. An evaluation of the effectiveness of the GPS system is provided with recommendations for potential users to consider, and general comments on the status of the technology.
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Atterbury Consultants, Inc. (ACI) has developed an integrated forest management system designed to meet user needs from GPS and forest field measurements, through office computations, mapping, appraisals, and reporting. ACI utilizes these systems for consulting, and sells the systems to customers. ACI has developed Distributor and Value Added Resale relationships with several key hardware and software manufacturers to support this integrated system and to bring the best prices and capability to our customers.
The system brings together Handhelds, PCs, and Workstations utilizing a variety of software. Software packages include Global Positioning Systems, Geographic Information Systems, Image Processing systems, Timber Cruising, and Forest Inventory packages. The core of the integrated system is PC based technology utilizing this wide range of software linked as an operational unit. Once data is entered into the system whether from a series of GPS satellites, handheld field computers, or from keypunched field measurements, it flows from one program to another as needed, frequently transparent to the operator.
The overall system is built around the concept of multi-level processing on computers and software suitable for each level. This utilizes the strengths of each component at the appropriate processing level. la other words, weather and shock proof handheld computers for field data collection; powerful desktop PC's for office processing; and workstations when processing very large and complex data sets.
The standardizing of many hardware and software components means that data and processing can be passed from system to system with relative ease. A major effort in the Atterbury system has been to make the transfers as transparent and painless to the operator as possible.
The basic field computer is the Corvallis Microtechnology, Inc. MCV-GPS Handheld unit. Data collection begins with the handheld GPS unit in the field where State Plane Coordinate readings are taken and stored in the handheld computer. If the operator is measuring timber for an appraisal, boundary points as well as plot centers can be captured and stored for later use. The CMT units are environmentally sealed and shock resistant.
Coordinate points can be pre-entered in the office for use in the field to assist in locating field points or locations. With up to four Megabytes of RAM memory, the unit will store a large number of GPS points as well as other types of field data.
Data collection for tree measurements and other plot information is collected with the same handheld computer utilizing Atterbury Consultant's program called SUPER EASY, or one of several other ACI programs. A high level of error detection is built in the data entry interface. The measurements are stored in the handheld for later processing on an office system.
Field crews on extended assignments frequently use a notebook computer to download data from the handheld units every day. This reduces the possibility for data loss and helps keep the data organized. Downloading each day's data is important since the operation is in RAM memory, and Murphy's Law will come into play sooner or later.
Although the data can be processed on a variety of PC's, the Atterbury standard is a 486-66DX with a minimum of 16 Mb of memory, 500 Mb of hard disk, and a high resolution video board and 17" monitor. This platform is fully capable of handling the GPS processing necessary to convert field measurements to useful information, process timber cruising and inventory data, and can also handle the complex GIS and image processing as well.
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The field GPS measurements and SUPER EASY or other forest measurements are transferred to the office PC based SUPER A.C.E. program for processing. The data is again edited and processing occurs on the PC. GPS readings are extracted and corrected with information from a base station with a known location. The corrected GPS points are then transferred back into the database, and also into AutoCAD for further processing.
The field timber measurements and corrected GPS points are transferred into the Forest Land Inventory Planning System (F.L.I.P.S.) on the same computer. This software provides complete processing of the field measurements and yields a variety of reports such as age class summaries, growth summaries, catalog reports, stand tables, log stock tables, and others. The F.L.I.P.S. program has the capability to produce appraisal reports using a sophisticated but easy to use transportation model, as well as price screen, and cost screens. Log prices can be input in a variety of species, sort, and grade combinations. Prices may also be varied by log length or log diameter.
GIS processing is accomplished in ArcCAD, the ESRI GIS system that utilizes AutoCAD for graphics processing and digitizing. ArcCAD provides the maps and map acreage's to support reporting and management. Plot location are also becoming increasingly more important due to Forest Practice Laws and environmental concerns.
The GIS ArcCAD and F.L.I.P.S. packages are linked by Atterbury's software package called FLIPTOMAP. This program transfers data back and forth between the forest inventory program and the ArcCAD GIS program. This process is largely transparent to the user, but is very powerful.
On large projects, large areas, or when high speed processing is required, data is transferred over an IBM network to one of two IBM RS 6000 UNIX Workstations. These units have workstation ArcINFO for full GIS processing. Generated files are then networked back to the PCs for further processing.
The Workstations will ultimately have all Atterbury software loaded in UNIX format for high level processing.
If Image Processing is determined to be a part of the project, the processing is done on a larger PC. The Atterbury standard Image Processing PC has 32 Mb of memory, 1+ GB of disk space, and normally a 1024 X 768 monitor. The TNTmips Image Processing software is used to access and process both GIS and image data from a variety of sources. GPS data is used to enhance georeferencing images and maps.
A variety of hardware is used to produce outputs, depending on the final product. HP LaserJets are used for black and white letter size prints from all systems. Since output from all programs can be moved through Windows 3.1 to word processing or publishing software, the Laserjet is a real workhorse for the system.
High quality color maps can be output on an "E" size color pen plotter, or the more heavily used HP DesignJet 650C Color Ink Jet plotter. This plotter will produce electrostatic like outputs for far less than the cost of an electrostatic plotter and in minutes compared to hours for a pen plotter.
Smaller 11" X 17" size color plots and prints are produced on the HP XL300 Paint Jet. This printer also is a primary output for the Image Processing system. The 11" X 17" size is maintained throughout the Image Processing system from scanner to printer in order to work with the 9" X 9" aerial photos that are used in resource management.
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The need for better, more accurate field measurements of location coordinates is being driven by rapidly escalating high values of land, and even higher values of the timber resource. Correct measurements of boundaries, critical features, and especially acres, are very critical when timber values can now exceed $50,000 per acre.
Forested properties frequently have poor quality maps and map databases. This is especially critical if market values for forest properties are to be established. Few forest properties have good georeferenced control, much less good surveys, with many surveys dating back to the last century. GPS offers an opportunity to alleviate many of the problems generated by the poor map base.
GPS offers the opportunity to obtain relatively accurate locations at low cost with skills possessed by foresters and appraisers. They are able to verify if they are on right property, add to the accuracy of acreage calculations, locate or verify property corners, traverse locations, and locate roads and road improvements. Sometimes coordinate data is preloaded for navigational purposes.
The State of Oregon and the US Forest Service are using handheld GPS units to map bike trails and off-road vehicle usage. This is done faster and cheaper than with aerial photogrammetry. The Handheld GPS unit allows point information to be captured with notes and annotation. Following differential correction on an office PC, they will have very accurate maps of the trails and usage.
Land owners are beginning to hire, buy, or rent GPS units to do internal property subdivisions and land planning prior to formal expense of surveying. The Handheld GPS unit is much cheaper and easier during the planning stages than using formal surveys, especially with nearly direct input to a CAD system like AutoCAD.
GPS may be the only line or point control in remote and unsurveyed areas. Many forested lands are still unsurveyed, other than on a gross level, and even then not below the square mile level.
Locating critical stream points, logging landings, soil problems, critical species locations, possible road locations, drainage structures, etc. all are becoming features easily located and recorded by Handheld GPS. The annotation features are especially valuable in recording these features since they need to be identified in some detail for use in later reports.
The process of deliberately producing inaccuracies through Selective Availability (SA) should end for GPS to realize its full potential. This process severely restricts GPS from being fully utilized. The industries that are struggling to utilize GPS should continue to make themselves heard even though the military is currently adamant on keeping SA. Removing SA will not remove the need to use base station data to correct field measurements since SA is not the only source of error. It will greatly reduce errors for navigation operations in the field.
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Small handheld GPS receivers require the operator to manually save data and they also are one use only. The CMT GPS Handheld allows auto storage of points from up to six satellites. It also allows other calculations and applications, such as timber cruising and log scaling.
This capability to do many jobs with one unit is why Atterbury Consultants sees the GPS Handheld as an addition to existing processes and procedures, not a basis for a new "empire" as so often happens with new technology. It will be utilized as a part of a much larger overall system.
Expensive base station installation and obtaining correction data appears to be the most costly part of GPS implementation. Even if you go the expense of a base station, GPS is still inexpensive when compared to obtaining comparable data from other sources or by other means. The high quality handheld units are less than $4,000.
Operation of the GPS units is relatively simple and easy to learn. As with any computer technology, GPS requires discipline to assure steps are followed and time is allowed for readings to stabilize. Few training classes are currently available for GPS, but many dealers are beginning to offer classes in support of their sales of GPS units. Atterbury Consultants has GPS training seminars scheduled regularly throughout the year.
Operators must learn the limits for their local GPS working area in terms of terrain, vegetation, etc. that may block or interfere with signals. Operators may need to move their measure point to get good signals, or change time of day for measurements in order to capture the right number of satellites.
GPS, as well as any computer based tool, is just that, a tool. Do not let it become an overpowering "system." Treat GPS as another tool in your tool box of labor saving - read money saving - devices. There will still be places where formal surveying is required; where distance measurements must be made by chain; pacing still works; and don't throw away the hand compass.
Atterbury Consultants, Inc. 1994, F.L.I.P.S. User's Manual, Atterbury Consultants, Inc., Beaverton Oregon
Atterbury Consultants, Inc. 1994, SUPER A.C.E. User's Manual, Atterbury Consultants, Inc., Beaverton Oregon
Corvallis Microtechnology, Inc. 1993, MC-GPS Operators Manual. Corvallis Microtechnology Inc., Corvallis, Oregon
Hurn J. 1989, GPS. A Guide To The Next Utility, Trimble Navigation, Ltd., Sunnyvale, California
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