GISdevelopment.net ---> AARS ---> ACRS 1992 ---> Education The Swedish ISY Contribution A Rosenqvist, H. Osterlund Swedish Space Corporation P.O. Box 4207 S-17104 Solna Sweden Abstract The Swedish contribution in the celebration of the International Space Year has materialized in an active participation in the World Forest Watch project of the Earth Science and Technology panel but also in the Training in Remote Sensing Applications programme within the panel Education and Applications. The Swedish World Forest Watch contributions have been formed under the theme of "Remote Sensing for Forest Management". The projects comprise a wide range of forest and forestry remote sensing applications using different technical approaches. 1. Background During the planning of the World Forest Watch (WFW) project, under the panel of Earth Science and Technology, a Swedish participation was discussed within the Swedish National Space Board (SNSB). After the initial international planning of the global WFW project contributions, the idea grew that Sweden, having well recognized scientific as well as practical experiences in the field of forest and forestry applications should contribute to this project. With a good knowledge of the domestic activities in the field of forest and forestry applications of remote sensing, the Swedish Space Corporation (SSC) gathered the research community with in-house experts of forest applications, to outline a Swedish ISY World Forest Watch contribution. It was mutually agreed upon to form this contribution under the theme "Remote Sensing for Forest Management". The projects represent a spectrum of remote sensing applications with the aim of increasing forestry planning and productivity or of surveying deforestation and forest damages. They show techniques from visual interpretation to advanced digital segmentation, applications for individual forest stands as well as entire nations from boreal Sweden to tropical Thailand and arid Sudan. By this approach it was thought that planned and ongoing activities could be extended, results published and displayed at several occasions, to inform a wider audience about the potential of remote sensing for sustainable management of forest resources, but also to strengthen national and international remote sensing co-operation. 2. Organization After the decision by SNSB to support the Swedish WFW initiative, the planning and undertaking of the subprojects emerged in the late spring of 1990. The coordination of the eight WFW projects was ensured by establishing a Swedish ISY Coordinator (SISYC), undertaken by SSC. The task of SISYC was to materialize the results of the joint effort and to accomplish this in cooperation with the Swedish remote sensing community. The projects included are undertaken by Swedish remote sensing research laboratories and SSC and are financed by SNSB. Presentations of projects are summarized below. A GIS/Remote Sensing Workstation for the Updating and Revision of Forest Maps At the Faculty of Forestry, Swedish University of Agricultural Sciences, an integrated method has been developed that uses old map Information and tabular data for the production of new forest information. The existing digital map data is edited interactively with new satellite imagery displayed on the monitor. Quantitative estimates of stand variables are derived from the reflectance properties of each stand. These estimated are statistically combined with tabular and ancillary data to produce new composite estimates with higher precision. Map regions still requiring additional refinement of delineation or estimation accuracy are surveyed and the new field inventory data incorporated in the estimates. The estimated costs using this new method are about half as compared to conventional ocular field inventories. The developed GIS/workstation software can be implemented on a 386-PC. Change Detection of Forest Stands Two methods for change detection of forest stands have been studied at the Faculty of Forestry, Swedish University of Agricultural Sciences. In the first method - visual interpretation of change imagery - the difference images from two SPOT P and Landsat TM band 7, respectively, are interpreted. The study showed that all clear felled areas and all soil scarification are possible to interpret. Cleanings and thinning can be delineated, but require field knowledge for identification. In a more authorized method - region based change classification - the compartments in the forest maps are divided into smaller regions of spectral homogeneity. This is automatically done based on the change image and the late satellite image. The regions are then classified in change classes. Using Landsat TM bands 5 and 7, all clear felled areas and soil scarification could be classified. Two thirds of the cleanings and thinninigs were correctly classified. Forest Management Planning with the Aid of GIS and Integrated Satellite Data Interactive digitization of satellite data with a GIS is a cost effective method adopted by SSC primarily for forest management planning. Merging SPOT Panchromatic data with multispectral data ensures the resolution needed fore forestry applications. The multispectral data often used is Landsat TM, band 4, 5 and 3. Digital cadastral maps and aerial photos can be incorporated to map features not interpretable in the satellite imagery, i.e. property lines or swamps. Contour lines can also be included to improve the basis for planning. The compartments are delineated and a preliminary forest map is produced in the traditional scale 1:10 000 to serve in forest inventory field work. Based on the field work, the map i revised. The maps can be used for forest management planning but also for planning of specific operations such as fertilization and cleaning. Forest Decline Monitoring Using Landsat TM, Digital Forest Map and Elevation Models The use of satellite for forest decline assessment is often complicated by terrain effects and stand characteristics, e.g. species composition and density. The effects were studied by the Swedish Environmental Research Institute variations in slope gradients, hardwood component, pine component and slope gradients have effect on the defoliation estimation. As no band rationing can compensate the terrain effect, a spruce defoliation model incorporating elevation model data, was developed. It uses slope/aspect data from the DTM and digital forest maps to account for terrain and compartment characteristics. Evaluation showed the model feasible to separate the defoliation into two classes; more than and less than 20% needle loss, respectively. Swedish Forest Information Atlas SSC has undertaken a national land use and vegetation cover classification during one year. 46 LANDSAT TM scenes and 12 SPOT XS scenes were geocoded to the Swedish National Grid. 900 digital map files (50m pixelsize ) showing 13 vegetation cover and land use classes were produced. These were merged and filtered to 500 m pixelsize to give the resulting image showing proportions of forest cover. The legend of the atlas comprise three forest classes - open and closed coniferous, deciduous - together with water, urban and open areas, Additional cartographic elements will be superimposed on the classification. The atlas will be produced both as printed maps and in digital format with a proposed pixelsize of 500m. Fig 1. Extract of the forest atlas Tropical Forest Monitoring with High Resolution Satellite Data The project was accomplished by SSC an the swedish Faculty of Forestry in co-operation with FAO to develop operational methods for a continuous tropical monitoring. The methodology was tested and evaluated for the Chiang Rai province in northern Thailand. Digitally enhanced multi-date Landsat colour hardcopies were interpreted. A point sampling design was used to estimate forest area cover. Aerial photographs were used as reference data to evaluate interpretation accuracy and to calibrate area estimates. The deforestation was calculated and showed that forest had decreased to 2/3 of its former areas in 13 years. The interpretations were digitized for further analysis. From these maps, yearly spatial distributions were interpolated to demonstrate the deforestation process in an animated video. Deforestation in African Drylands - Assessment of Changes in woody Vegetation in Semi Sudan The changes of woody vegetation in terms of areal extent and woody resources in the western Sudan 1973 - 87 have been studied by the Department of Physical Geography, University of Lund. Wood resources were quantified using the normalized vegetation index and irrigated and machanized rainfed agriculture was manually delineated. Maps were produced that show the extent of wooded areas and agriculture. The study concludes that the threat to woodlands and forest resources comes from the expansion of rainfed machanized agriculture. The extent of woodlands varies with climatic fluctuations and is more threatened by expansion of large agricultural schemes than by domestic use of fuel wood. Remote Sensing Education for Education in Sweden 1992 In support of the United Nations program for creation of indigenous capabilities of space science and technology in developing countries, Sweden has given a five-weeks course in remote sensing techniques and usage in June 1992. The course, which from now on is to be repeated every year, is aimed at university teachers and is open for participants from developing countries . The course is organised by the Department of Physical Geography, University of Stockholm and SSC Satellitbild. Fig 2. United nations Remote Sensing Training Course in Sweden, 1990 3. Activities Presentations of the ISY-WFW projects are given at domestic and international conference, exhibitions and workshops in oral and poster sessions. For this purpose a brochure titles The Swedish ISY Contribution, and a mobile exhibition, giving an overview of the different contributions, have been produced. Also, actions are being taken to distribute the ISY idea through media. Contacts are taken with radio and television broadcasting companies for participation in programmes with an environmental, scientific or technical profile. Daily newspapers receive press releases. Technical and scientific periodic journals are receiving project information and press material. Fig 3. The Swedish and Nordic ISY brochures. Please contact Swedish Corporation for free copies. Schools receive information about the Swedish activities in the field or remote sensing for forest monitoring and can have access to the material produced and for two years, a bus-born exhibition will tour Sweden, starting in late 1992. Sweden also participates and distribution of a Nordic ISY broachure, titled NORDIC Mission to Planet Earth, covering remote sensing activities in Denmark, Finland, Norway and Sweden. Major events during 1992 in which the Swedish ISY contribution is planned to be or have been presented include the following: Skogsveckan, Stockholm, Sweden Inventory of the forest environment, Umea, Sweden European ISY Conference, Munich, Germany Kartdagarna, Gavle, Sweden World Forest Watch Conference, Sao Jose dos Campos, Brazil ISPRS Congress, Washington D.C., USA Asian Conference on Remote Sensing, Ulaanbaatar, Mongolia. Asia Pacific ISY Conference, Tokyo, Japan.