Proceedings of the Symposium on Global and Environmental Monitoring: Proceedings of the Symposium on Global and Environmental Monitoring

Bibliographic data

Multivolume work

Persistent identifier:: 856665355

Title:: Proceedings of the Symposium on Global and Environmental Monitoring

Sub title:: techniques and impacts ; September 17 - 21, 1990, Victoria Conference Centre, Victoria, British Columbia, Canada

Year of publication:: 1990

Place of publication:: Victoria, BC

Publisher of the original:: [Verlag nicht ermittelbar]

Identifier (digital):: 856665355

Language:: English

Document type:: Multivolume work

Volume

Persistent identifier:: 856669164

Title:: Proceedings of the Symposium on Global and Environmental Monitoring

Sub title:: techniques and impacts; September 17 - 21, 1990, Victoria Conference Centre, Victoria, British Columbia, Canada

Scope:: XIV, 912 Seiten

Year of publication:: 1990

Place of publication:: Victoria, BC

Publisher of the original:: [Verlag nicht ermittelbar]

Identifier (digital):: 856669164

Illustration:: Illustrationen, Diagramme, Karten

Signature of the source:: ZS 312(28,7,1)

Language:: English

Usage licence:: Attribution 4.0 International (CC BY 4.0)

Editor:: International Society for Photogrammetry and Remote Sensing, Commission of Photographic and Remote Sensing Data

Publisher of the digital copy:: Technische Informationsbibliothek Hannover

Place of publication of the digital copy:: Hannover

Year of publication of the original:: 2016

Document type:: Volume

Collection:: Earth sciences

Chapter

Title:: [WP-2 LAND USE AND LAND COVER]

Document type:: Multivolume work

Structure type:: Chapter

Chapter

Title:: REVISING LAND USE/LAND COVER MAPS USING LANDSAT THEMATIC MAPPER IMAGERY. Bruce Thomas, Anthony M. Turner

Document type:: Multivolume work

Structure type:: Chapter

rangeland, agriculture with a minor woodland component. Figure 1. Location of Alberta Project Area (1-Peace River Zone; 2-Central Zone; and 3-Foothills Zone) METHODOLOGY Maps The method of land use change detection involved the use of the Canada Land Inventory (CLI) "Present Land Use" series (McClellan et al., 1968) . This map series covers most of the settled part of southern Canada at a scales of 1:50 000 or 1:63 360 and represents the most complete attempt at detailed, large area land use/land cover mapping in Canada. The maps date from the 1960's and have never been updated. Imagery Colour composites of TM bands 3, 5 and 4 respectively assigned to blue, green and red were enhanced with the boreal reflectance enhancement. The enhancement is a standard product which emphasizes the woodland cover and provides good scene-to- scene consistency (Ahern and Sirois, 1988). Boreal enhancements proved most useful in the Peace River and Central zones but less effective in the rangeland dominated environment of the Foothills zone. In an effort to improve the accuracy in the identifying and mapping losses in forest cover which dominated the land use changes, single TM band 3 black and white winter images for each scene centre were also used. In winter, open areas are blanketed with snow and appear white, while densely forested areas appear black or grey because of a lack of snow on the forest canopy. This high contrast enabled a rapid and straight-forward delineation of cleared forest areas, which were then be classified using the corresponding summer image. A total of 40 images with a common year of 1986 were interpreted for the three zones. East-west overlap between the satellite paths enabled several adjacent images to be used. This helped to overcome unexpected cloud cover, discontinuous snow cover or poor guality of some images. Interpretation Technique Land use changes were located by comparing the CLI "Present Land Use" maps with visually interpreted 1986 Landsat Thematic Mapper imagery. Visual image interpretation was a suitable means of gathering the required information over the large area because of low cost of visual imagery compared with digital imagery and classification. Additionally, the ability of a visual interpreter to make use of textural and contextual information not readily available to digital classifications was another reason for employing visual interpretation. The image transparencies were integrated with the land use maps using the Procom-2 optical transfer instrument. The instrument was equipped with the optional Stereo-Change Detection (SCD) module, a second projector assembly that allowed the winter and summer images to be co registered and interpreted simultaneously. The first step was to define a land cover classification. The 14 Canada Land Inventory "Present Land Use" classes were collapsed into 8 general classes capable of being discriminated with Thematic Mapper imagery (Table 1). One class (clearcuts) was added. It was formerly included as part of "unproductive woodland" category in the CLI classification. It was decided to include this additional class to document the extent of this type of change in the wooded environment. Using 1:20 000, 1:30 000 and 1:40 000 scale aerial photography as reference data of the land use types in Alberta, a general interpretation key was developed based on the spectral, textural and contextual aspects of classes as they appeared on the Thematic Mapper imagery (Table 2). With the imagery registered to the map, the change detection procedure consisted of systematically comparing a land use polygon on the map with its class on the imagery as determined from the classification key. If whole or part of a polygon appeared different from the expected appearance for a particular class, the change was delineated and classified using a two-letter code representing the pre to post change land use combination. RESULTS There were a total of 49 possible pre to post change land use combinations plus an additional "no change" class. Thirty of these change combinations were actually found and mapped. The amount of land use change observed by the project are shown in Table 3. Over 4 6 000 polygons of change were mapped corresponding to some 17 000 km 2 of changes or about 15% of the area surveyed. Significant regional variations were observed. The Peace River region had the greatest amount of change per unit area and the Foothills zone the least amount of change. Most of the change in two zones was from Woodland (T) 359

Access restriction

Copyright

fullscreen: Proceedings of the Symposium on Global and Environmental Monitoring (Part 1)

Multivolume work

Volume

Chapter

Chapter

Table of contents

Cite and reuse

Volume

Chapter

Image

Image fragment

Citation links

Citation recommendation