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DIGITAL TERRAIN MODELS – A HELPFUL TOOL FOR SUSTAINABLE MANAGEMENT AND DEVELOPMENT OF DEGRADED GREEK FOREST ECOSYSTEMS

Vasileios C. Drosos1*, Vasileios J. Giannoulas2, and Christos C. Stamatiou1

1School of Forestry and Management of the Environment and Natural Resources, Democritus University of Thrace, N. Orestiada, Greece / P.C. 682 00, Ath. Pantazidou 193 Str. *E-mail: vdrosos@fmenr.duth.gr, stamatioy@gmail.com
2Faculty of Forestry and Natural Environment, Aristotle University, Thessaloniki, Greece, University Campus, P.C. 541 24. E-mail: vgiannou@for.auth.gr

Abstract:

Most of the ecosystems of our country are classified as degraded natural ecosystems, due to more or less human impact on the near or distant past. Many of these ecosystems are currently experiencing an evolutionary process, after their relief of adverse human activities, which mainly depends on the condition of the soil, the ecological diversity of the region and the rational and sustainable human management. The digital representation of the terrain, with software easy to handle, is a key task of the Geotechnical – Engineering Scientist. Furthermore, it is necessary for the upgrade of the existing environment that the current state of the ground (aspects, soil-cover) and the proposed one (roads, new soil-cover, micro-works) are depicted on three-dimensional intelligibly form. This process requires detailed surveying with geodesic station or GPS and automatic transfer into appropriate software for processing – a comparison of existing and proposed state, through several options. Consequently, the following problem is raised: farming and sustainable management of the forest without road openings is unrealistic, on the contrary most of our country's forests are degraded and with low productivity. Therefore, it is difficult to find the golden mean between the services of the needs of the forest exploitation and protection and the principle of the optimization that should apply in all economic-technical studies. The aim of this essay is to examine the contribution of the digital elevation model and generally, the high technology, to setting a framework for sustainable management and development, which will contribute to the recovery of degraded forests in Greece. The background on which the modern analysis and design of the site takes place, is a digital design in two-dimensional and three-dimensional forms. In relation to the above both the design and construction of forest roads ought to depend on digital technology. It is the largest infrastructure work in the mountainous area and contributes to the intensification of forest exploitation in economic growth and gradual improvement of degraded mountain areas.

(Forestry Ideas, 2011, Vol. 17, No. 2) [Download]
Downloads: 1006

HIGH TECHNOLOGY IN FOREST ENGINEER WORKS

Vasileios C. Drosos*, Apostolos Kantartzis, and Rigas Giovannopoulos

School of Forestry and Managment of the Environment and Natural Resources, Democritus University of Thrace, N. Orestiada, Greece / P.C. 682 00. Ath. Pantazidou 193 Str. *E-mail: vdrosos@fmenr.duth.gr, apkan2002@yahoo.gr, rigas_giovannopoulos@yahoo.gr

Abstract:

Older methods and instruments were characterized by low accuracy or low productivity and high costs of fieldwork. From the 80s appeared on the market new types of instruments identified to measure accurately, productively, with a small amount of field work, but large cost of purchasing the instrument and modified analytical methods and efficiency. The era that we are living is characterized by evolutions of great importance in the sector of space applications. Especially, in the field of geodesy science, the applications of position determination with the use of satellite systems in global scale offered valuable solutions in chronic problems while creating new prospects but also greater demands. GPS and GLONASS are continually improving and the European Galileo and Chinese Compass systems are emerging to provide additional benefits for world-wide users. The main target of this research is the investigation of the possibilities of the triple frequency GPS at field work for forest map-ping. Previous works has been done by many researchers in all over the world. However, in this paper we concentrate on woodland area with receivers of two (2) frequencies (dual frequency) for both GPS and GLONASS satellites on. Also be able to receive signals from the third frequency GPS L5 and GALILEO, COMPASS satellites and the new L2C frequency for better and faster fixing in these environments. Finally are concluded proposals for the survey work in the forest cadastre, the forest opening up and the forest road construction, the study of temporal changes in the earth surface, for the measuring of forest data and for the civil engineer works.

(Forestry Ideas, 2011, Vol. 17, No. 2) [Download]
Downloads: 854

RELATIONSHIP BETWEEN COLOUR CHANGE AND SURFACE HARDNESS IN THERMALLY MODIFIED SESSILE OAK WOOD

Nebojša Todorović* and Zdravko Popović

University of Belgrade, Faculty of Forestry – Department of Wood Processing, Kneza Višeslava 1, 11030 Belgrade, Serbia. *E-mail: nebojsa.todorovic@sfb.rs

Abstract:

The aim of this paper is to investigate the relationship between the surface hardness (Brinell's hardness) and colour change of thermally modified Sessile oak (Quercus sessiliflora Salisb.) wood. The material was taken from the coppice forests of the National Park Đerdap in eastern Serbia. Two groups of samples were selected from sapwood and from heartwood. The samples were heat treated at 170 °C, 190 °C and 210 °C for 4 hours. Radial hardness and CIELab (L*a*b*) coordinates of wood colour were investigated before and after the thermal treatment. The obtained results indicate that thermal treatment causes a reduction of CIElab coordinates and radial hardness whereas colour change (∆E) increases with the rise in temperature. All the measured coordinates of the CIELab system have positive values in all the analyzed samples. The positive correlation between lightness (L*) and hardness was determined, whereas colour change has negative impact on radial hardness of oak wood. The results presented in this paper indicate that the colour can be used for assessment of hardness of thermally modified Sessile oak wood.

(Forestry Ideas, 2011, Vol. 17, No. 2) [Download]
Downloads: 1819

EVALUATE AND DEVELOP AN EXISTING FOREST ROAD NETWORK BASE ON ENVIRONMENTAL FACTORS

Sattar Ezzati1*, Kyumars Mohammadi Sammani2, Akbar Najafi1, and Hamid Hasangholipour3

1Department of Forestry, Tarbiat Modares University, P. Box: 64414-356, Noor, Iran. *E-mail: S.ezzati@modares.ac.ir, E-mail: a.najafi@modares.ac.ir
2Department of Forestry, Kurdistan University, Sanandaj, Iran. E-mail: K.Mohammadi@uok.ac.ir
3Department of Forestry, Guilan University, Rasht, Iran. BSc gratuated in forestry. E-mail: H.hasangholipour@yahoo.com

Abstract:

Designing the forest road network is a complex and specialized process including route selection, field investigation, data analyzing, and finally determining the best variant coping with the site-specific road locations. The present study was designated to evaluate the existing forest road network and to develop the existing forest road network in the mountainous forests, north of Iran (Savadkoh district). In order to find appropriate options for road routing, firstly the effective environmental factors were identified such as slope, aspect and elevation layers. In the next step, the Geographic Information System (GIS) was applied to evaluate and develop an existing forest road network. The length and density of the existing road network were about 1.75 km and 10.14 m·ha–1, respectively. The new variant was developed with regard to forest and physiographic conditions using PEGGER software. The length and density of new variant were 1.38 km and 8 m·ha–1, respectively. The development of the existing road network has been increased the total road density from 10.15 to 18.16 m·ha–1 and also could cover 55.5 % of the forest area for timber harvesting operations. Approximately, 32.14 % total length of the new variant was passed on 15–30 % slope and 64 % of the new variant was passed on 30–60 % slope terrains, which is more likely to be minimal negative environmental impact. Moreover, the new variant has had a better performance than the existing road. The results showed that this method can be more helpful and road network can be designed quickly with less cost than traditional method. Also, it was confirmed by computer analysis that application of this system at such level can be effective in preparation of the optimum routes designing plans.

(Forestry Ideas, 2011, Vol. 17, No. 2) [Download]
Downloads: 998

FIRST RESULTS OF RAPD-ANALYSES OF INTRASPECIFIC POLYMORPHISM OF DOUGLAS-FIR CULTIVATED IN BULGARIA AND BELARUS

Volha Chyzhyk1, Tatsiana Antsipava1*, Vladimir Torchik1, and Emil Popov2

1National Academy of Sciences of Belarus, State Scientific Institution "Central Botanical Gardens", Surganova Street-2b 220012, Minsk, Belarus. *E-mail: hbc@mserv.bas-net.by
2Forest Research Institute – Bulgarian Academy of Sciences 132 St. Kliment Ohridski blvd., Sofia 1756, Bulgaria. E-mail: emilpopov99@hotmail.com

Abstract:

The aim of the research was to elucidate existing intraspecific polymorphism of Douglas-fir plantations in Bulgaria and Belarus using Random Amplified Polymorphic DNA (RAPD) markers and to estimate genetic similarities and distances. RAPD-primers that reveal high polymorphism were selected. Seven Douglas-fir populations from Bulgaria and one from the Central Botanical Gardens in Belarus were included in the study, and individual RAPD pat-terns for 8 primers were obtained. The obtained RAPD-patterns were used to calculate the genetic distances among the populations studied.

(Forestry Ideas, 2011, Vol. 17, No. 2) [Download]
Issues: 1-5 | 6-10 | 11-14