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Airborne-GeoTechnologies Aid Baikal Lake Basin
Management study identifies ecological risk zones
By N.V. Malysheva The maintenance of forest sustainability in the Baikal region in Russia is a requirement for preserving this unique lake. The strategy and main elements of the regional forest monitoring system are based on remote sensing and Geographic Information Systems (GIS) applications. Using this data, the performance of the forest's protective functions and resources inside the Baikal Basin were obtained using Color Infrared (CIR) space & aerial survey images. Remote sensing and GIS data allowed for the identification and selection of ecological risk zones with unsustainable forest ecosystems.
The forest managers, scientists, government employees, and citizens have recognized that the future of Lake Baikal(which contains 20 percent of world's fresh water and harbors endemic species of plants and animals (those found nowhere else on this planet) is literally in their hands.
The major part of the Baikal Basin (20 million hectors, or 72%, from more than 24 million ha of total area inside Russian boundaries) is occupied by forests. Furthermore, 18 million ha of this area have been under the authority of federal bodies. One specific discovery from this forest management effort is that 52% of the forests within the Baikal Basin performed diverse, protective functions (mainly water-protection, erosion-prevention and soil-protection functions), requiring special management practices.
The maintenance of the ecological forest sustainability in the Baikal Region is an obligatory condition for preserving the uniqueness of this lake, which is proposed for inclusion on the world heritage list. The main impediments to forest sustainability are fires, unfavorable meteorological phenomena (high-winds, hail, and heavy snowfalls), as well as unreasonable utilization of forest resources, industrial emissions, and unor- ganized tourism. Impacts caused by dendrophilous insects, fungi infestations and droughts, coupled with unfavorable meteorological conditions and technogenic pollution, result in the weakening and the destruction of the forests. The main management activity to take place in the Baikal Region has been associated with harvesting.
To maintain ecological sustainability within the forests, it's necessary to establish a monitoring system for organizing timely detection of unfavorable impacts, as well as for optimizing management activities. Monitoring the Baikal Region required accom- plishing the following objectives:
„obtaining data for a forest region that occupies a vast region (more than 18 million ha);
„ describing forest conditions in terms of generalized ecologi- cal indices that define forest sustainability;
„ analyzing all disturbances within the spatial structure of the forest lands and assessing what affects such disturbances have upon the protective functions of the forest.
The Baikal Lake Basin is the first test territory where a regional forest monitoring strategy(including establishing methods of data collection using remote sensing, in conjunction with GIS data storage and image interpretation programs) has been developed. The main elements of the system provided for collection, storage, analyzing, processing, updating, manipulating and displaying of spatially distributed forest data. This information system was developed by the All-Russian Scientific Research & Information Center for Forest Resources, with financial support from the Russian Federal Forest Service. The system was aimed at the application of the data derived from satellite images and selective aerial photography in combination with some ground observations as well as from employment of forest management and cartographic materials, and reference statistical data.
The establishment of the monitoring system can be roughly divided into 4 phases:
„system design;
„individual modules formation;
„integrating modules into a common system;
„test exploitation of system. The System Design Phase
System design comprised the collection of the cartographic materials, the "base mapping", and selection of territorial units meant for systematizing the monitoring data. The aim of "base mapping" was to register the forest state at a fixed date as a "reference point" in order to observe the dynamics of the forest composition and other features.
Base forest mapping envisaged the compiling of a set of "paper" maps on the common scale of 1:1,000,000 in order to follow the sustainability of forests. Such maps were based on forest inventory data as well as on information derived from previous ground observations. The map set included the following thematic maps: regional landscapes, forests, forest fuel materials, regional hydrological division, river runoff, etc. A forest map was to be considered as a main thematic map within this set of maps until, it was discovered, there was no such map available on the scale 1:1,000,000 to depict the current state of forest vegetation. It turned out to be necessary to develop methods for compiling this map according to up-to-date sources like remote imagery.
The resulting 1:1,000,000 scale forest map within the framework of the regional information system is intended for observing changes in forest boundaries, updating the interpretation of materials derived from newer observations, and registering changes in forest composition as primary coniferous stands are substituted for derivative deciduous stands.
The map contained the following special content:
„Dominant tree species and shrubs (common and Siberian pines, spruce, fir, Siberian larch, birch, aspen, elfin wood, and other shrubs) to prevail over the area.
„Associated tree species shown within generalized het- erogeneous contours alternate sites that have different dominant species.
„Forests disturbed by fires and cuttings in different years
„Unstocked forest lands (clear-cuttings or burned areas)
„Non-forest areas including arable lands, pastures, bogs, sub- alpine meadows, rocky barring, stone-placers' sands, saline lands.
Special content of the map is derived from CIR space photographs on the scale 1:270,000 and 1:1,000,000 using images from "Kosmos" and "Resurs-F" satellites.
The more important issue is believed to be a territorial division of the Baikal Region in order to single out long-term reference monitoring units known as natural and territorial observation units (NTOU) and subsequently to localize the generalized indices of forest sustainability. Taking into consideration the forest monitoring system developed for this unique region, a basin wide approach was assumed as a basis of the natural and territorial division. While dividing or joining basins up, the main principle to be kept in mind is to find areas that possess natural complexes constituting functional units that are similar with regard to runoff conditions. The boundaries of these observation units are fixed according to topographic map data on the scale 1:1,000,000. This data can then be used to create a digital cartographic data base. Individual Modules Formation Phase
Of paramount importance at this phase was the task of developing data acquisition methods for estimating the forest's sustainability, and obtaining detailed information about the forest's state at the local sites. The local sites highlight risk zones susceptible to industrial emission, forest pests and diseases, forest fires, logging disturbances, and other calamities.
Satellite imagery served as one source for the initial data describing the forest state in the whole region. While not oriented towards one or another set of specific indices, satellite images take into account special features and interpretations that required that a multi-purpose method be developed for collecting this initial data.
Establishing a set of selected indices made it possible to obtain generalized estimates of ecological sustainability within each territorial observation unit singled out during the preceding phase. The following indices were chosen for evaluating forest sustainability:
„percentage of forest lands, i.e., forest stocked areas as com- pared to total area of observation unit (%);
„integrity, i.e., stocked areas as compared to forest lands(%);
„share of coniferous stands (%);
„share of mature coniferous stands (%);
„share of unstocked stands (%).
Dynamics of these indices caused by natural and anthro- pogenic factors testified to the changes in each forest ecosystem. Determination of the mentioned indices consisted of identifying land categories and calculating their percentages. Identification of land categories is based upon utilizing interpretative indicators. Interpretation was carried out according to data collected from the CIR or multispectral satellite images taken by Russian satellites.
Apart from the developed method for assessing forest sustainability in the whole region, the following methods were developed to collect the detail information:
„The method of forest health assessment within area of technogenic pollution according to large scale aerial CIR photographs.
„The method of reforestation dynamics assessment at cutting and burnt-over areas according to space and aerial photo- graphs Integrating Modules Into A Common System
While interpreting images within the framework of hydrological division, the values of the indices were loaded into a Landscape and Ecological Data Base. This LEDB provided the analytical "core" for the information system, and was intended to handle the loading, storage, updating, and analysis of all data accumulated during the forest monitoring program.
IBM compatible computers running under MS DOS were used for the LEDB operation and for producing tables, reports and maps, as required for users' activities. The database management software CLARION was selected for maintaining the LEBD and for developing a "friendly" interface. The geo-relational structure of the data base supported the data storage and the one-to-one correspondence between attribute data records using identification codes.
The approach chosen for division of the territory into observation units made it possible to cluster individual units into different ordered river basins or hydrological regions for obtaining the integrate features, and to monitor for the forest state within the drainage basins. In order to find the correlation of indices with water balance elements, 206 observation units, 12 hydrological regions and sub-regions were selected within the Baikal Basin.
The initial information is updated annually by periodically obtained data about current changes in the forest. Registration of current changes such as forest fire data, data about burnt-over and cut-over areas, pest and disease outbreaks, forest areas damaged by high-winds, soil drought, industrial emissions, snow avalanches, etc., are provided throughout the inter-revision period. The repeated detecting of indices for estimation of the forest sustainability is carried out once every 10 years using current space and aerial photo images.
The analysis of forest dynamics via comparison of initial data with updated indices is required to update the data base and to fulfill the ad-hoc requests. The overlaying of digital cartographic data, which contains the boundaries of NTOU and boundaries of forest enterprises with LEDB within the GIS environment, allows researchers to recalculate the interpretation indices for the forest enterprises. This account is needed in order to satisfy the forest management requirements of the monitoring system.
Forty four forest enterprises, 3 national parks, and 2 reservations are located within Baikal Lake Basin. Whereas the dynamics of forest statistic data have been evaluated traditionally by both administrative and management division units, the application of remote imagery and GIS have provided advantages that are allowing for the analysis of the ecological indices within these forest enterprises, national parks, and reservations. ARC/INFO version 7.0 for WS has been applied for such analysis. The software was installed on a SUNSPARCstation 10 under UNIX. The creation of a digital cartographic data base consisting of topographical data coupled with boundaries of natural and territorial divisions, plus administrative and management divisions were required for this experiment. The applied investigations are allowing for the development of a GIS for spatial analysis and selection of the ecological risk zones. One should provide the special detail observation within these detected risk zones when forest monitoring system tests detect exploitation. Due to the combination of satellite and aerial remotely sensed imagery and GIS applications, 3 river basins (NTOU) with heavy disturbed forest ecosystems, and 25 river basins (NTOU) with unsustainable forest ecosystems have been discovered in the Baikal Lake Basin. About the Author:
Natalia V. Malysheva , Ph.D. in Geographical Sciences, has two decade of experience in RS application for forestry and forest mapping. Recently as a chief of RS Methods Department of All-Russian Scientific Research & Information Centre for Forest Resources (ARICFR) she has managed th GIS research projects dealing with forest monitoring of protected areas inside Russia. She may be reached at office e-mail:[email protected] or phone:7(095)332-5135(office), 571-6011(home).
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