FOREST TAXATION DATA GEOPROCESSING FOR ASSESSMENT OF FOREST FIRE DANGER CAUSED BY FOCUSED SUNLIGHT

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1 FOREST TAXATION DATA GEOPROCESSING FOR ASSESSMENT OF FOREST FIRE DANGER CAUSED BY FOCUSED SUNLIGHT Elena P. Yankovich Assoc Prof Nikolay V. Baranovskiy National Research Tomsk Polytechnic University, Russian Federation ABSTRACT Predicting and estimating forest fire danger is an important part of the system of forest fire prevention and elimination. Geographic information systems (GIS) have instruments for creation, transformation and integration of variables concerned with fire danger. They allow finding geographical and analytical relations to identify areas with high fire incidents probability. Analysis of existing forest fire danger assessment systems showed that they take into consideration such factors of forest fire initiation as anthropogenic load and storm activity. Theoretical estimates and results of experiments prove that there is possibility of forest fire due to action of focused sunlight along with previously mentioned factors. Assessment of forest fire danger caused by focused sunlight is realizable by analysis of forest taxation description of a given forest area. None of the existing systems recognizes this factor. This paper describes geoinformation system that includes toolset for analysis of forest areas taxation aimed at quantitative evaluation of forest fire danger. Radiant heat flux is considered to be reference source of ignition. The system is capable of evaluating probability and classification of forestry quarters by level of fire danger. Performance of algorithm of forest fire danger caused by focused sunlight evaluation in geoinformation system is shown on typical forest area of Timiryazevskoe forestry of Tomsk region. Conceptual basis of GIS system is physically and mathematically proved methodic of forest fire danger assessment. Computational formulae of probability of forest fire initiation are derived from basic statement of probability theory. The system is implemented in specialized software ArcGIS. The system uses standard user interface with additional functionality for assessment of probability of fire incidents in the forest quarters area caused by focused sunlight. Received information is displayed on the map. For extra capabilities in evaluating forest fire danger unique instruments were developed in built-in Python programming language. Probability maps of forest fire initiation in forest quarters were created using proposed model. Application of these maps will be an important component of the forest fire control system. Keywords: Geoprocessing, Forest Fire Danger, Forest Taxation Data, Focused Sunlight 607

2 INTRODUCTION Estimating forest fire danger and forecasting is important for preventing forest fires. Along with generally recognized causes such as human activity and thunderstorms, forest fuel layer can ignite under action of focused sun radiation [1]. Possibility of forest fuel layer ignition at sun energy concentration about kw/m 2 was shown theoretically [2] and experimentally [3]. Sunlight concentrators include glass containers, their splinters and resin of coniferous trees. Physically proven method of assessment of forest fire danger caused by focused sunlight was developed [4]. It is possible to estimate forest fire danger of this sort from forest fuel layer composition. Its characteristics are typically defined during forest taxation. Thus to estimate forest fire probability it is necessary to analyze forest inventory data. Geographic information systems (GIS) have tools for creation, modification and integration of variables related to fire danger. They allow finding geographical and analytical relation to reveal zones with high probability of fire incidents. The article describes set of geoinformation system tools, which analyze forest taxation data to evaluate quantitatively forest fire danger caused by focused sunlight. METHODS According to structure of forest management of Russian Federation, primary inventory unit is a plot [5]. In general, district forestry consists of quarters and quarters consist of plots. Several district forestries compose a forestry. Quarter is the most convenient to use as a cartography unit during spatial analysis of territory, since its borders and location are defined precisely. Vegetation composition data is kept in taxation (inventory) books and refers to plots. So, to classify quarters by levels of fire danger on basis of species composition and age of stand it is necessary to determine amount of fire-prone plots in every quarter. Every plot can exhibit significant difference in composition and condition of forest fuel layer. For an instance, it can be hill or valley, mixed forest with prevalence of coniferous or deciduous species. Respective researches showed that all plots by levels of fire danger can be divided in two groups: low-flammable and fire-prone. Most fireprone are plots with old conifer forest [4]. The probability of forest fire P(C) associated with focused sunlight can be estimated as: P(C) N FS, (1) N TS where N FS and N TS are number of fire-prone plots and total number of plots for a given area, respectively. Fire danger level is determined by calculated value of fire probability. Fire danger is categorized into five classes from extreme to low. Solution for assessment of forest fire danger caused by focused sunlight is made in ArcGIS environment. This software includes wide range of system geoprocessing tools and built-in Python programming language allows users creation of additional 608

3 applications. We have developed additional tools for quantitative assessment of forest fire danger caused by focused sunlight. RESULTS To calculate probability, classify forest quarters by levels of fire danger and visualize received information on the map, it is necessary to apply geoprocessing tools to input data according to proposed methods [6]. First step in this process is to determine fire danger of each plot by analyzing taxation data, which is stored as MS Excel table. The table includes following mandatory columns: name of district forestry, quarter number, plot number, species composition of vegetation and age. Estimation of fire danger of the plot uses developed tool, which includes procedure of separation of low-flammable plots. As a result of tool s work autonomous table, which contains attribute field defining the plot as a fire-prone or not, is created. Next step is calculation of forest fire danger of each quarter. Before calculating probability of fire from formula (1) it is required to define amount of plots in the quarter, both total and fire-prone, which is achieved with ArcGIS system tool Summary Statistics [7]. Input data is table containing information about fire danger of the plots, combination fields are name of the district forestry and quarter name. After execution of the tool, a table is created. This table contains following columns: name of district forestry, quarter number, amount of plots in each quarter and number of fireprone plots. AddField tool creates one more column where CalculateField computes probability of fire caused by focused sunlight by formula (1) [7]. Calculated values range from 0 to 1 (Fig. 1). Derived values are divided in five classes of forest fire danger: 1) low; 2) moderate; average; high; extreme (Fig. 1). Fig. 1. Resulting table Variables represent quantitative and qualitative estimation of forest fire danger. where, : ObjectID - object identifier, N_kvartal - number of quarter, Count_vydel - total sites in quarter, Count_fire - number of fire-prone sites, Probability - probability of forest fire within a given quarter, Level estimated level of forest fire danger Third step visualization of received information. Attributive data from autonomous table needs to be added to attribute table of spatial feature class, which contains information about location of forest quarters. To combine autonomous and spatial tables JoinField tool is used. Joining bases on two key fields (name of district forestry and quarter number). 609

4 Final step is mapping information displaying quarters by levels of fire danger. Apply Symbology From Layer tool (it applies display properties of a chosen layer to the input one) is used. Input layer is forest quarters including attribute fields with levels of fire danger, symbol layer is a saved layer with specified legend. It is not hard to notice that in given geoprocessing workflow each consequent tool uses output data from preceding one; therefore, they are assembled into a single tool in ModelBuilder application (Fig. 2). Fig. 2. Computation algorithm Thus a tool which allows estimating of probability of forest fire caused by focused sunlight and visualization of results is created. Dialog box of the tool is represented on Fig. 3. For the work user needs to specify following parameters: workspace (geodatabase), input MS Excel table (taxation data), attribute table of spatial feature class (location of the quarters) and template symbology layer. 610

5 Fig. 3. Dialog box of the tool The tools creates a map of forest fire danger caused by focused sunlight (Fig. 4) Fig. 4. The map of forest fire danger caused by focused sunlight (on the example of Timiryazevskoe district forestry of Tomsk region) CONCLUSION This work presents tools for assessment of probability of ignition due to action of focused sunlight on forest fuel layer. Forest quarters are classified and quarters with possibility of fire caused by focused sunlight are marked. Maps of fire danger are created. Input data processing is made in ArcGIS environment. This system can be used by according agencies and institutions for monitoring and preventing forest fires, as well as minimization of their consequences. Acknowledgments Work is executed with financial support of the state contract of the Ministry of Education and Science within FCP «Researches and developments in priority directions of development of a scientificallytechnological complex of Russia on ». The state contract REFERENCES 611

6 [1] Kuznetsov G.V., Baranovskiy N.V. Focused sun's rays and forest fire danger: new concept. Proceedings of SPIE Vol. 8890, paper ; doi: / [2] Baranovskiy N.V. Numerical study of forest fuel layer ignition by the focused sunlight action. Butlerov Communications, Russia, vol. 26. N 11. pp , [3] Baranovskiy N.V. Experimental research of forest fuel layer ignition by the focused sunlight. Fire and Explosion Safety, Russia, vol. 21. N 9. pp , [4] Baranovskiy N.V. New approach to forest fire danger estimation of large forests in the conditions of focused sunlight action. Fire and Explosion Safety, Russia,. vol. 22. N 1, pp , [5] Kuznetsov V.I., Kozlov N.I., Khomyakov P.M. Mathematical modelling of evolution of wood for management of a forestry. Russia, 232pp, [6] Baranovskiy N.V., Yankovich E.P. Methodical and technical bases of use of the land taxation data of large forests with a view of a quantitative estimation of forest fire danger. Ecological systems and devices. Russia, N 3. pp. 3 12, 2014 [7] ArcGIS 9. Geoprocessing Commands Quick Reference Guide, ESRI Press, Redlands, USA, 220 pp,