Tatiana Pristova

Institute of Biology, Komi Scientific Centre, Ural Branch, Russian Academy of Sciences. 28 Kommunisticheskaya st., Syktyvkar, Russia. E-mail: pristova@ib.komisc.ru

Forest cutting and natural reforestation essentially affect the species diversity, structure and live biomass of trees and green forest floor (GFF). Spruce forests, different-aged mixed deciduous-coniferous stands, and birch young forest in the taiga zone of northeastern Russia (Komi Republic) have been studied. Tree species are represented by Betula pendula, B. pubescens, Populus tremula, Pinus sylvestris, Picea obovata, Abies sibirica. Soil types at study objects are weakly peaty-weakly podzolic gley soil and illuvial-humus-iron podzol. Before cutting instead of todays deciduous forests there grew a 150-190-year-old spruce forest. GFF live biomass vary from 0.4 upto 3.9 t·ha^-1 and reaches its highest values in spruce for-est and the lowest values in 37-year-old birch-aspen forest. High resistant of phytomass in spruce forest and 90-years-old birch-aspen forest, low resistant phytomass characterizes middle-aged deciduous-coniferous forests. Weight proportion grasses/mosses makes 1:1 in middle-aged deciduous-coniferous forests, 3:5 in birch young forest and 90-years-old birch-aspen forest, and 1:8 in spruce forest.

Panayot Panayotov^1*, Kuncho Kalmukov², and Momchil Panayotov³

¹Faculty of Forest Industry, University of Forestry, 10 Kliment Ohridski Bulv., 1756 Sofia, Bulgaria. ^*E-mail: ppanayotov45@abv.bg
²Experimental Station for Fast-Growing Forest Species, 18 Nove str., Svishtov, Bulgaria. E-mail: kkalmukov@abv.bg
³Faculty of Forestry, University of Forestry, 10 Kliment Ohridski Bulv., 1756 Sofia, Bulgaria. E-mail: mp2@abv.bg

We studied the growth in height, diameter, volume and the most important wood proper-ties of 11-year old Ailanthus altissima (Mill.) Swingle trees grown at the Research station for fast-growing species near Svishtov, Bulgaria. We found that the height growth was most intensive during the first years with maximum rate in the 5^th year. The diameter and volume growth were continuous and by the 11^th year still had not reached a decrease in the rate. The wood density at air-dry condition (w=7.5 %) was 620 kg·m^-3, at absolutely dry condition (w=0 %) was 580 kg·m^-3, while at maximally saturated with water (density in row condition) it was 1045 kg·m^-3. The volume shrinkage was 14.85 %. Head hardness, studied following Brinel method (in direction parallel to the grains), was 83.41 N·mm^-2, the hardness in radial direction was 61.48 N·mm^-2and in tangential direction - 52.03 N·mm^-2. The bending strength (MOR) of air-dry wood was 71.11 N·mm^-2. The modulus of elasticity (MOE) was 11.906 GPa. The compression strength parallel to the fibres was 55.83 N·mm^-2. The shear strength parallel to the fibers in tangential plain was 14.41 N·mm^-2, while in radial plain was 13.65 N·mm^-2. Our results show that Ailanthus altissima is underestimated fast-growing species, whose wood can be successfully used for production of paper and furniture. Therefore we consider appropriate a recommendation to start trials with establishment of experimental plantation.

Krassimira Petkova

Department of Sylviculture, Faculty of Forestry. University of Forestry. 10 Kliment Ohridski Blvd. 1756 Sofia. Bulgaria. E-mail: kpet@abv.bg

The aim of the study wais to make a comparative analysis of the growth rate of 54 Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) provenances. The provenance test was established in the spring of 1990 with 3-year-old (3+0) seedlings planted in a 2x2 m plot design and two replications. The provenances originated from the North America and were separated into Coastal, Continental and Western Cascade groups. At age 20 growth rate was studied in terms of height and diameter, and stem volume. Coastal provenances demonstrated the best growth parameters, followed by Western Cascade Mountains and continental provenances. The provenances showing fastest growth provenances were Bremerton, of the coastal group, and Darrington, Newhalem and Idanha of the Western Cascade group. These provenances possessed also high resistance to fungal pathogens. Ten continental provenances had the lowest growth rate and productivity and were highly susceptible to the fungal pathogens Rhabdocline pseudotsugae and Phaeocryptopus gaumannii. Darrington from the Western Cascades in Washington is the recommended provenance for future afforestations with Douglas-fir in Bulgaria.

Vasileios C. Drosos

School of Forestry and Managment of the Environment and Natural Resources, Democritus University of Thrace, N. Orestiada, Greece / P.C. 682 00. E-mail: vdrosos@fmenr.duth.gr

The main concern of a forester is to be able to collect and maintain accurate and detailed data in order to cope successfully with current needs but also to anticipate future situations. Generally speaking, the Cadastre is a tool for planning, rationalization and development of the country and environmental protection. The development of mountain areas consists of the development of anthropogenic influences, which – like every form of economic development – is usually accompanied by negative environmental impacts. Thus it is necessary to define the criteria considering Environmental Impact Assessment (EIA). The aim of this paper is to investigate and to clearly demonstrate the contribution of forest cadastre and EIA in Forest Management Planning. Forest cadastre, which is a special cadastre, should be in line with the technical specifications of the National one. The total cost is not just techno-economic, but also environmental, all of which constitutes the cost of the work. We must develop practical and objective methods in order to assess the environmental impacts in alternative solutions in order to determine the location that makes the work compatible with the natural environment. There can be no development and rational management of the forest without a forest cadastre. On the other hand, however, most of the country’s forests are degraded and of low productivity and most of them play a protective role. So the EIA is essential for the planning of any work.

Vasileios C. Drosos^* and Liampas G. Sarantis-Angelos

School of Forestry and Managment of the Environment and Natural Resources, Democritus University of Thrace, Ath. Pantazidou 193, P.C. 682 00, Orestiada, Greece. ^*E-mail: vdrosos@fmenr.duth.gr

The rapid development of technology and the broad use of computers during the recent years have resulted in new emerging opportunities across all technical domains. Thus, there have been developed the ambitious Digital Terrain Models (DTMs) to exploit these opportunities and leverage their capabilities for the common good. The DTMs provide the basis for developing a wide range of applications related to earth sciences. To be more specific, the former in Geoinformatics enable the possibilities of modelling, analysis and performance measurement of spatial phenomena related to topography or other technical areas with similar spatial properties. The DTMs can be used in conjunction with the Geographic Information Systems (GIS) in order to create a system which could be able to provide analytical data and information over terrain properties. In this essay a combination of DTMs with Geographical Information Systems (GIS) is undertaken, in an effort to create a hybrid out of these technologies. The initial thinking was to create a digital database that could provide comprehensive information over the number of fires, land areas and living species and finally the reaction time of the forest office commissions for the entire Greek state. What is more, a secondary objective was to monitor the efficiency degree of land exploitation by using DTMs in a targeted area. To a further extent, the combination of DTMs' information data such as vegetation, air temperature and wind direction, can contribute better in more efficient ways of forest fires prevention and suppression. In addition, the combination of the former along with the lands' efficient exploitation offers unlimited possibilities of spatial planning applications within the national digital cadastre. Subsequently, there are in our disposability unlimited scheduling capabilities to reduce arbitrary structure, violation of forest and other public territories, and an urban and regional environmentally friendly planning. To sum up, the DTMs assist us in a better and more rational development, protection and enhancement of mountainous areas.