0784-B1
O.A. Atroshchanka, S.I. Minkevich 1
Forest is one of the few exploitable natural resources in Belarus. As a branch of economy the forestry in Belarus is highly perspective.
In general forestry is a part of the Belarusian Forestry and Forest industry consists of forestry, forest industry, wood processing and wood-pulp and paper industries etc. It includes nearly 5 thousand enterprises and production facilities with different forms of property (including over 470 large and medium-scale enterprises) with over 146 thousand employees.
Forestry resources are one of the main natural riches of Belarus. The total stock of timber constitutes 1.3 billion cubic meters.* The forestry fund occupies about 9.2 million hectares. The forest lands is about 8.3 million hectares. One third of the territory of Belarus is covered by forests.
Forests in Belarus are owned by the State and mostly belonged to the Committee of Forestry (about 7 mill. ha or 76.1% of the total area of the forestry fund). The rest part of forest owners is represented by the Committee of Defence, collective farms and associations, the research institutes and Administration.
The structure of the Committee of Forestry is represented by 800 forestries (average area is about 8 thousand ha), 88 forest enterprises (average area is about 70 thousand ha) and 6 Forestry Boards.
A specific feature of the raw resources of timber in Belarus is domination of industrial valuable tree species (pine, spruce, birch, see figure 1*).
Figure 1
Young forests constitute 36.6%, ripining 14.2%, and mature and overmature 4.8%.
Depending on their commercial value and their location, the Republic's forests are divided into two groups. The first group of forests having water protection, sanitary and other protective functions takes up 44 per cent, while the second one, which is of commercial value, constitutes 56 per cent of forests.
Managing forests in today's ever-changing world is becoming an increasingly complex and demanding challenge to forest managers.
There are two main forest inventory systems in Belarus: 1) basis standwise forest inventory (every 15 years for every forest enterprise, so called stand-level inventory); 2) operative continuous standwise forest inventory on the basis of a database of the unique Belarusian version of the Geographical Information System called GIS "Forest resources" for forest enterprises.
The operative continuous standwise forest inventory has been used for the purposes of operational forest management planning. It covers all forests and the information from the forest inventory is used by forest enterprises for justifying and calibrating their results.
A subcompartment databank "Forest fund" on the base of a standwise forest inventory data (including more than 3.0 mln subcompartments) was created in 1976. The subcompartment databank "Forest fund" is used for working out forest statistics, forest evaluation and forecasting forest dynamics. It is also applied to estimate versatile information on forest resources, sustainable forestry and forest growing alternatives.
The creation of the Geographical Information System "Forest resources" for forest enterprises has allowed to elaborate a new technology of the operative continuous standwise forest inventory.
The current changes in forest fund (e.g. clear cuttings and thinnings, forest planting and reforestation, fires and windfalls, new data of forest mensuration at a level for every stand etc.) viz. so called actualisation of forest fund are being inserted in the subcompartment databank "Forest Fund" and also in the database of GIS "Forest resources" by foresters for every forest enterprise.
The GIS "Forest resources" at a level of forest enterprise is created on the basis of domestic software - GIS FORMAP in MS Windows 95/NT. It uses geographically referenced data as well as non-spatial data and includes operations which support spatial analysis. It is used to work with information stored in computer databases (manipulate, summarise, query, edit, visualise).
The GIS "Forest resources" has multiwindows, easily adjusted interface. It also lets large opportunities in managing of different properties and facilities e.g. input, editing, changing, measuring distances and areas, filtration, transformation, combining maps of the same area together, control and inquiries to the cartographical and subcompartment databases etc. The system has the converter in ARC/INFO, import / export of a cartographical database to a format DXF, mechanism OLE Automation for Microsoft Office, converter from forest inventory database SMBD-L. It gives an opportunity of creation of new databases, objects and layers on digital maps through the mechanism Borland Database Engine. There are two GIS' databases at a level of forest enterprise: 1) cartographical database in a DXF format, created on the basis of the digital forest maps of the scale 1:10 000; 2) subcompartment database for every forest compartment (about 300 parameters) in a format Paradox and SMBD ORACLE.
The GIS ,,Forest Resources" software' solutions is intended to provide our foresters with powerful tools for better analysis and decision making in the matter of practical tasks on the estimation of forest resources, current planning of forest management activity (e.g. planting and reforestation, fire-prevention and forest protection of measures, planning and preparation of cutting fund, creation of thematic forest maps, cadastre estimation and forest monitoring) and supposed to let them perform tasks such as developing long-term supply strategies, forecasting silvicultural stock, determining harvesting system options, and many more.
The State Forest Assessment is based on operative continuous standwise forest inventory database elaborated at the State Forest Inventory Enterprise "UP BELGOSLES", taking into account changes registered during forest inventory and afterwards, including forest felling and reforestation activities as well as changes in forest ownership.
Therefore, the most important part of the activities of the State Forest Inventory Enterprise "UP BELGOSLES" is represented by the National Forest Inventory, which means the State Forest Inventory Enterprise carries a significant responsibility for supplying society with information about the forest. Forest Inventory Department of the Belarusian State Technological University carries out research, student and post-graduate education within the fields of forest inventory, forest management planning, forest mensuration, forest biometry, GIS and remote sensing. The activities of the department also encompass statistical consultation and methodological support in the developing of forest inventory systems in Belarus to the State Forest Inventory Enterprise "UP BELGOSLES" as well as in the using of the geographical information system GIS "Forest Resources" to the foresters.
Forest inventory is obligatory to all forest owners. During the inventory forest stands are singled out, their quantitative and qualitative characteristics are provided, forest health is assessed and silvicultural measures foreseen. Forest management plans are prepared for forest enterprises, state parks, recreational and protected areas. The general forest management plans are prepared for all forest properties on the territory, controlled by forest enterprises as well as individual management plans - for each private property.
A forest inventory by sampling method was applied for estimation of forest resources in the area of Hrodna Forestry Board in the western part of Belarus. A stratified systematic cluster sampling design was utilized in field measurements. The design was constructed on the basis of information from earlier stand-level inventories, aerial photographs and the available budget. The distance between two tracts (2x2km) was 4 kilometers both in north-south and east-west directions. A three stage systematic sample was used in field measurements.
Totally 8059 sample plots (Bitterlich and sample plots with fixed radius) were established on forestry land and 7690 were on forest land. Trees were measured on those field plots, which intersect forest land. Trees are selected using PPS sampling, the inclusion probability of a tree being proportional to its cross-sectional area at a height of 1,3m.
The estimates for the area of Hrodna Forestry Board and for the areas of different stratums (e.g. predominated tree species etc.) were computed from field measurements only. Description of statistical procedures used to analyse data including procedures for sampling error estimation. Some new models have been constructed and their parameters estimated on the basis of sample trees data.
Ongoing research topic is to improve and change, to some extent existing sampling design and to develop a new sampling inventory system for the entire country which will utilize field plot measurements (the core of forest inventory) as well as other information sources (satellite image and digital map data etc.).
It must be conducted every year by sampling methods, combining measuring on permanent and temporary plots and their assessment by satellite maps, digital maps as well as aerial photos. Thus, a precise and effective information on the condition of forests, harvesting and regeneration, volume of growing stock, mortality increment, their balance, structure, use for strategical forest planing, and forestry regulation on a state level will be obtained.
The National Forest Inventory System by sampling method must be incorporated as a part of powerful Forest Inventory and monitoring System of Europe for the purposes of forest monitoring and receiving of forest statistics at the National level.
Remote sensing forestry related data from EOScan ground station is used for the purposes of forest monitoring in Belarus. EOScan ground station is purposed to receive data from the EOS (Terra and Aqua) satellites in the Direct Broadcast (DB) mode. The Terra is a polar-orbiting satellite with the revolution period of about 100 minutes. In the DB mode, it transmits information from the MODIS imaging radiometer with the data rate of 13.125 Mbps. The MODIS forms an image of the Earth within approx. 2000 km wide swath along the flight track, in 36 spectral channels, with the spatial resolution from 250 to 1000 m.
It is supposed that data from the EOS satellites will be used in the powerful operative system of forest monitoring and forest statistics receiving which is being actively developed.
The forest monitoring system consists of several levels:
1) Remote sensing data from satellites (EOScan, Landsat 5,7 TM, IRS);
2) Remote sensing data obtained by airmethods - scanning of forest canopy from aeroplane;
3) digital forest maps from GIS "Forest Resources";
4) field measurements data obtained on permanent plots of forest monitoring system; database of forest inventory by sampling method.
* - Forest statistics have been obtained on the basis of "a standwise continuous forest inventory" by the State Forest Assessment Enterprise "BELGOSLES".
1 Professor and Assistant at Belarusian State Technological University