Makale Koleksiyonu

Bu koleksiyon için kalıcı URI

Güncel Gönderiler

Listeleniyor 1 - 20 / 141
  • Öğe
    Evaluation of forest management plans in conjunction with the cadastral information: The case of Agva and Beykoz, Istanbul
    (Istanbul Univ, Fac Forestry, 2016) Çakır, Günay; Güler, Alptuğ; Zengin, Hayati; Değermenci, Ahmet Salih
    Determination of land ownership and boundaries is one of the most important purposes of the urban and rural land laws. There can be some boundary problems while preparing forestry area of any urban area when there is not consistency between the borders constructed by different state organizations like land cadastre, forest cadastre and forest management and planning teams. This study aims to illustrate these conflicts in forestry applications process of two different areas (Agva and Beykoz) having different characteristics. The study was carried out in Agva and Beykoz districts in the province of Istanbul and focused on the integration in the land and forest cadastral systems. The Beykoz and Agva Forest Planning Units have different characteristics in terms of population (urban and rural) and social impacts. Analyses of the data obtained from the field studies which it was utilized for the investigation of the data obtained from various base maps, were carried out using GIS software. Many inhabitants of the villages in the Agva Planning Unit had migrated from the district. Thus, in accordance with Boundary Law number of 6831 part of 2/B some parcels of villages in Agva were determined to be acting forest and were reassigned as forest land. In Beykoz, however, areas of this nature were few and the destruction of the forests was great. The spatial analysis of the study made it possible to remove discrepancies occurring in the cadastral situation by preparing forest management plans. Consequently, if land cadastre and forest cadastre units carry out work in coordination to determine the cadastral situation, a basis for forest management plans can be established and cadastral problems greatly reduced.
  • Öğe
    Experimental arid land afforestation in Central Anatolia, Turkey
    (Springer, 2018) Yıldız, Oktay; Altundağ, Ernaz; Çetin, Bilal; Güner, S. Teoman; Sargıncı, Murat; Toprak, Bülent
    The afforestation of arid lands faces many challenges, and perhaps the most important key for success is choosing one or more species that are adapted well for local environmental conditions. We explored species that would be suitable for the steppe region of Central Anatolia. Intensive site preparation included ripping the subsoil (to 80 cm) and plowing the upper soil before planting seedlings of Elaeagnus angustifolia, Robinia pseudoacacia, Fraxinus angustifolia, and Pinus nigra were used as tree species. We also tested the success of several shrub species: Amygdalus orientalis, Calligonum polygonoides, and Spartium junceum. After five growing seasons, E. angustifolia showed the highest survival, with 80% of planted seedlings remaining. For the shrubs, A. orientalis was the most successful species with a 95% survival rate. Broad-leaved trees grew a cumulative average of 34 cm in height in 5 years, whereas P. nigra seedings grew only 9 cm. The greatest height growth occurred in the shrubs, with A. orientalis gaining 40 cm in height in 5 years. Overall, E. angustifolia and A. orientalis appeared best suited for afforestation in these areas. R. pseodoacacia and F. angustifolia may also be used as alternative species.
  • Öğe
    Evapotranspiration from a Mixed Deciduous Forest Ecosystem
    (Springer, 2010) Özhan, Süleyman; Gökbulak, Ferhat; Serengil, Yusuf; Özcan, Mehmet
    The objectives of this paper were to determine evapotranspiration (ET) from an oak-beech dominated forest ecosystem in Belgrad Forest near Istanbul, Turkey by using catchment water balance method and compare it with potential evapotranspiration (PET) computed by using Thornthwaite method. Data, in this study, were derived from a long-term hydrological research conducted in Belgrad Forest. Long-term stream flow measurements (1979-1995) were conducted with concrete sharp-crested V-notch weirs instrumented with automatic water level recorders in two close experimental watersheds. ET values of the watersheds were determined by using water balance equation. Average annual ET values from the old growth oak-beech forest ecosystem during the monitoring period of 17 years were around 833.20 mm for W-I and 752.07 mm for W-IV whereas PET estimated according to Thornthwaite method was found to be 726.14 mm. In other words, 79.68%, and 71.93% of mean annual precipitation evaporated from W-I and W-IV, respectively while 69.45% of precipitation evaporated according to Thornthwaite method. PET estimated with Thornthwaite method differed significantly only from W-I whereas W-I and W-IV had similar ET values.
  • Öğe
    Evolution of Modern Forest Management Planning in the Republic of Turkey
    (Soc Amer Foresters, 2013) Zengin, Hayati; Yeşil, Ahmet; Asan, Ünal; Bettinger, Pete; Cieszewski, Chris; Siry, Jacek P.
    The Republic of Turkey has a long history of forest management that has undergone considerable change over the last 100 years due to political, economic, and social issues. For the most part, state-owned forestlands (the largest forest owner category) have been managed under plans arising from a conventional process that used classic techniques to regulate activities and allowable harvest levels. However, over the last 35 years, four different types of forest management plans have been developed (conventional and model) and applied universally or to a specific region of the country. Today, a single type of planning process is used, which emphasizes ecological and environmental conditions, multiple uses of the landscape, and social concerns. Although management and planning are evolving, implementation is challenged by a continued focus on wood production rather than on other concerns, a lack of skilled personnel and qualified decisionmakers, and other societal conflicts.
  • Öğe
    EXCLOSURE EFFECTS ON RECOVERY OF SELECTED SOIL PROPERTIES IN A MIXED BROADLEAF FOREST RECREATION SITE
    (Wiley-Blackwell, 2013) Özcan, Mehmet; Gökbulak, Ferhat; Hızal, Ahmet
    Human-caused trampling that results from excessive recreational use has caused damage to soil and vegetation in forest ecosystems in the Belgrad Forest of Istanbul. The objectives of this study were to examine effects of exclosure on selected soil properties and to determine the recovery time required for soil characteristics in a broadleaf forest recreation site. Litter biomass and topsoil (0-15cm) were sampled in the forest, exclosure and recreational sites, and soil samples were analysed for saturation capacity, permeability, bulk density, total porosity, organic matter, root biomass, electrical conductivity and soil pH. Results showed that saturation capacity, permeability, total porosity and organic matter increased whereas bulk density decreased significantly in the topsoil under the exclosure, and all these soil properties in the topsoil of the exclosure were greater than those of recreational site. When effects of main factors were compared, averaging over sampling year and soil sampling depth, soils from the exclosure had significantly greater saturation capacity, permeability, total porosity, organic matter and litter biomass and lower bulk density values than the soils from recreational site. Six years of exclosure was effective in improving most of the soil properties in the topsoil. When topsoil and subsoil are considered together, it is obvious that a longer time period is needed for soil recovery in the forest recreational sites. Copyright (c) 2011 John Wiley & Sons, Ltd.
  • Öğe
    Evaluation of the tender results of forest road constructions: A case study in Bolu Regional Directorate
    (Istanbul Univ, Fac Forestry, 2017) Türk, Yılmaz; Gümüş, Selçuk
    The construction of forest roads in Turkey follows a tender process conducted by the General Directorate of Forestry. The amount of work (i.e., excavation volume) is estimated for the approximate cost schedule required for the tender. Unexpected disputes have occurred during the process of finalizing the contracts because measurements are determined by a preliminary survey done prior to preparation of a detailed project proposal. The aim of this study was to compare the road construction data that was calculated during the tender process to the exact values that were obtained as a result of construction. A total of 34 forest roads constructed by Bolu Forest Regional Directorate between 2007 and 2014 were studied. Data were obtained from the tender dossiers to evaluate and compare the cost estimated for the tenders to the actual progress values (excavation quantities, excavation features and costs) of these projects. In addition, these roads have been evaluated according to forest road technical standards. The total length of the assessed roads was 73,879 m, the total costs were USD 977,138, and a total of 726,366 m(3) was excavated during the construction of these roads. Paired sample t-tests demonstrated a statistical difference between the tender cost estimates and the progress payment amounts, and between the estimated amounts of very hard rock excavation and the actual amounts of very hard rock excavation.
  • Öğe
    EVALUATING URBANIZATION, FRAGMENTATION AND LAND USE/LAND COVER CHANGE PATTERN IN ISTANBUL CITY, TURKEY FROM 1971 TO 2002
    (Wiley, 2008) Çakır, Günay; Ün, C.; Başkent, Emin Zeki; Köse, Selahattin; Sivrikaya, Fatih; Keleş, Sedat
    Spatiotemporal analysis of landscape dynamics is crucial in formulating an appropriate set of actions in landscape management. This paper presents a large scale analysis of the spatiotemporal structure of Istanbul, a highly urbanized city in Turkey, from 1971 to 2002 using forest cover type maps analysed with geographical information systems (GIS) and a spatial statistics programme. The quantitative evidence indicated that increasing population and expanding urbanization caused drastic changes to the temporal and spatial dynamics of land use/land cover pattern in Istanbul. There was a net increase of 5387.3ha in total forested areas (1.0 per cent) due to mainly reforestation activities even though the population increased three times over a 31-year period. Increase in number of patches and decrease in mean patch size together demonstrated that the landscape developed into a more fragmented structure that would negatively affect biodiversity and the resilience of the ecosystems. In conclusion, plain increase in forest areas may not always be a favourable situation. The quality, composition and the configuration of forest landscape should also be analysed to present the dynamics of ecosystem in terms of ecological and economical sustainability over a longer time and larger area. Copyright (C) 2008 John Wiley & Sons, Ltd.
  • Öğe
    Evaluating land use/land cover changes and fragmentation in the camili forest planning unit of northeastern Turkey from 1972 to 2005
    (Wiley, 2007) Sivrikaya, Fatih; Çakır, Günay; Kadıoğulları, Ali İhsan; Keleş, Sedat; Başkent, Emin Zeki; Terzioğlu, Salih
    Changes in land use/land cover have important consequences on the management of natural resources including soil and water quality, global climatic systems and biodiversity. This study analysed the spatial and temporal pattern of land use/land cover change in the Camili forest planning unit that includes the Camili Biosphere Reserve Area within the Caucasian hotspot, in the northeast corner of Turkey. To assess the patterns during a 33-year period, the necessary data were obtained from forest stand maps and evaluated with Geographic Information Systems and FRAGSTATS. Results showed that the total forested areas increased from 19 946 center dot 5 ha (78 center dot 6% of the study area) in 1972 to 20 797 center dot 3 ha (81 center dot 9 per cent) in 2005 with a slight net increase of 851 ha. Softwood cover types (411 center dot 8 ha) completely transitioned to other cover types over 33-year period. In terms of spatial configuration, the total number of forest fragments increased from 172 to 608, and mean size of forest patch (NIPS) decreased from 147 center dot 7 ha to 41 center dot 8 ha during the period. Nearly 84 per cent of the patches in 1972 and 93 per cent of them in 2005 generally seem to concentrate into 0-100 ha patch size class, indicating more fragmented landscape over time that might create a risk for the maintenance of biodiversity of the area. There were apparent trends in the temporal structure of forest landscape, some of which may issue from mismanagement of the area, social conflict, and illegal utilization of forest resources due to ineffective forest protection measurements. The study revealed that it is important to understand both spatial and temporal changes of land use/land cover and their effects on landscape pattern to disclose the implications for land use planning and management. Copyright (C) 2007 John Wiley & Sons, Ltd.
  • Öğe
    European Ash (Fraxinus excelsior L.) Dieback: Disintegrating forest in the mountain protected areas, Czech Republic
    (Osterreichischer Agrarverlag, 2015) Vacek, Stanislav; Vacek, Zdenek; Bulusek, Daniel; Putalova, Tereza; Sargıncı, Murat; Schwarz, Otakar; Moser, W. Keith
    European ash (Fraxinus excelsior) is an important tree species in most temperate forests in Europe. Its future is threatened however, especially by an invasive fungus, Hymenoscyphus fraxineus (Hymenoscyphus pseudoalbidus, Chalara fraxinea). The current study is focused on the health of ash in the Krkonose Mountains National Park, Czech Republic. On permanent research plots containing mixtures of ash and other species, the stands' health condition was evaluated annually in 2009-2015, by using radial increment and foliage of 350 trees as indicators, with emphasis on the cenotic arrangement and morphological type of the crown. The results show mean annual decrease in foliation of 1.6-2.7% for live trees and 2.4-4.6% in all live and dead trees, with an overall mortality of 16.3% of trees. During the latter half of the study, the defoliation dynamics and dieback accelerated, especially at lower altitude and waterlogged sites. In 2012-2015, the mean annual decrease in foliation reached 3.9% in live trees and 6.3% in all trees. The mean radial increment was significantly lower 2 years after the purported fungi attack and the mean foliage density was significantly lower 6 years after the attack compared to healthy trees. Based on the evaluation of the results and the literature, a set of practical guidelines was established for management strategies and conservation of threatened European ash in similar stand conditions.
  • Öğe
    Estimation of stand type parameters and land cover using Landsat-7 ETM image: A case study from Turkey
    (Mdpi, 2008) Günlü, Alkan; Sivrikaya, Fatih; Başkent, Emin Zeki; Keleş, Sedat; Çakır, Günay; Kadıoğulları, Ali İhsan
    Remote sensing has been considered a low-cost, large-area coverage forest information resource ideally suited to broad-scale forest inventory objectives. The objective of this study is to determine stand type parameters such as crown closure, development stage and stand types, and land cover obtained from Landsat 7 ETM image and forest cover type map ( stand type map). The research also focuses on classifying and mapping the stand parameters with the spatial analysis functions of GIS. In the study, stand parameters determined by forest cover type map and remote sensing methods were compared and contrasted to evaluate the potential use of the remote sensing methods. The result showed that development stage were estimated with Landsat 7 ETM image using supervised classification with a 0.89 kappa statistic value and 92% overall accuracy assessments. Among the features, development stages were the most successfully classified stand parameters in classification process. According to the spatial accuracy assessment results, development stages also had the highest accuracy of 72.2%. As can be seen in the results, spatial accuracy is lower than classification accuracy. Stand type had the lowest accuracy of 32.8. In conclusion, it could be stated that development stages, crown closure and land cover could be determined at an acceptable level using Landsat 7 ETM image. However, Landsat 7 ETM image do not provide means to map and monitor minor vegetation communities and stand types at stand level due to low spatial resolution. High resolution satellite images could be used either alone or with field survey data.
  • Öğe
    Estimation of peak runoff and frequency in an ungauged stream of a forested watershed for flood hazard mapping
    (Northeast Forestry Univ, 2019) Karagül, Refik; Çitgez, Tarik
    Kaynasli District in the western Black Sea region of Turkey has long been vulnerable to frequent flood damage due to the establishment of settlements within and around stream channels without regard to fluctuating peak-streamflow frequencies. The aim of this research was to determine the measures needed to protect the towns and villages from this type of damage. Daily total precipitation data for 1975-2010 were analysed, and rainfall-runoff models developed to estimate the potential yearly maximum discharge from each stream of sub-watersheds dominated by forests and/or agriculture. This was then calculated for different frequencies of the yearly maximum discharge. Flood analysis and mapping was modified via the one-dimensional Hydrologic Engineering Centers-River Analysis System software to produce potential maximum discharge and geometric data for Kaynasli Creek. As the main creek of the sub-watershed, its cross-section was shown to be insufficient and incapable of containing the maximum discharge at the 100-year frequency presumed for the watershed, and subsequently was seen as having a high level of casualty risk. It was concluded that the one dimensional model could be useful, but 2D models were more suitable for these types of watersheds.
  • Öğe
    Hydro-physical properties of soils developed from different parent materials
    (Elsevier, 2008) Gökbulak, Ferhat; Özcan, Mehmet
    The objectives of this study were to compare some selected hydro-physical properties of soils developed from different parent material under the same climate type, similar topography and vegetation cover and to present significant differences in the soil characteristics with numerical values. For this purpose, five different sites with similar topography, vegetation cover, the same climate type, and different parent materials were selected in the northeast part of Turkey where some studies were previously carried out by scientists from the Faculty of Forestry at Istanbul University. The parent materials in the sites were granite, clayey limestone (upper triassic), clayey limestone (upper cretaceous), neocene, and arkose. Results indicated that all properties studied except for saturation capacity and particle density of soils differed significantly with respect to the parent materials. Compared to other soil types developed from the parent materials, granite formed soils with greater sand and lower silt contents, numerically greater porosity, and significantly higher dispersion ratio and organic matter. on the other hand, soils formed on arkose parent materials had the lowest pH value, numerically the greatest available water content and saturation capacity and organic matter percentage. (c) 2008 Elsevier B.V. All rights reserved.
  • Öğe
    Growth response and nitrogen use physiology of Fraser fir (Abies fraseri), red pine (Pinus resinosa), and hybrid poplar under amino acid nutrition
    (Springer, 2013) Wilson, Alexa R.; Nzokou, Pascal; Güney, Deniz; Kulaç, Şemsettin
    Plants can assimilate amino acids from soils. This has been demonstrated in controlled environments and soils of various forest ecosystems. However, the role of root-absorbed amino acids in plant nitrogen nutrition is still poorly understood. We investigated the agroecological performance and nutrient use physiology of two conifers (Abies fraseri and Pinus resinosa) and one hardwood species (hybrid poplar) under amino acid fertilization. Arginine fertilizer (arGrow(A (R)) Complete) was applied at varying rates (0, 56, 112, 224, and 336 kg N/ha) and compared to an inorganic control treatment (ammonium sulfate 112 kg N/ha). Parameters monitored included tree growth response, foliar nitrogen concentration, and inorganic nitrogen leaching below the rootzone. Results obtained indicate a significant growth and foliar nitrogen response to amino acid treatments, with increasing amino acid application leading to greater growth and foliar nitrogen. However, rates two to three times higher than that of the inorganic control were necessary to provide similar growth and foliar nitrogen responses. These observations were suggested to be due to competition with soil microbes for organic nitrogen, growth inhibition due to the presence of large concentrations of amino acids, or adsorption to cation exchange sites. Amino acid applications did not increase the leaching of inorganic nitrogen due either to the binding of positively charged arginine cations to exchange sites or rapid mineralization followed by plant assimilation. Mineral nitrogen collected in leachate samples increased with the application rate suggesting at least some mineralization in high amino acid application rates. We conclude that growth response and nitrogen use physiology of these species when treated with arginine are largely controlled by soil processes including microbial competition and adsorption. Further studies are being conducted to confirm these hypotheses.
  • Öğe
    Growth and Physiological Response of Fraser Fir [Abies fraseri (Pursh) Poke] Seedlings to Water Stress: Seasonal and Diurnal Variations in Photosynthetic Pigments and Carbohydrate Concentration
    (Amer Soc Horticultural Science, 2012) Kulaç, Şemsettin; Nzokou, Pascal; Güney, Deniz; Cregg, Bert Michael; Turna, İbrahim
    Four-year-old seedlings of Abies fraseri [(Pursh) Poir] (fraser fir) were grown in semicontrolled conditions in hoop houses with five watering regimes (0.00, 0.62, 1.25, 2.50, and 3.70 cm/week) with the goal of determining the seasonal variation in the physiological response to drought stress. Drought stress was monitored by measuring predawn (Psi pd) and midday (Psi md) potentials in a subset of plants from each treatment. Physiological variables monitored were chlorophyll fluorescence (F-v/F-m), ChI a, ChI b, total carotenes, and total carbohydrate concentrations. Morphological characteristics including height growth, root collar diameter, and terminal shoot growth were also measured. Predawn stem water potential values were generally higher (-0.8 to 1.9 Mpa) than midday values (-1.3 to 2.9 Mpa). Irrigation consistently increased Psi pd and Psi md compared with non-irrigated treatments. Photosynthetic pigments (ChI a, ChI b, and carotenes) decreased midseason (14 July) and increased toward the end of the season (25 Aug.) in predawn and midday measurements. There was a significant effect (P < 0.05) of drought stress on photosynthetic pigment concentrations in predawn and midday samples in the late-season measurements (25 Aug.). These results were accompanied with a similar significant difference in F-v/F-m between non-irrigated and irrigated trees. We concluded that significant effects observed on photosynthetic pigment concentrations in some of the treatments did not affect carbohydrate concentrations. Exposure of A. fraseri to water stress did not cause a reduction in supply of metabolic carbohydrates; consequently, the decline and mortality in water-stressed plants can only be the result of hydraulic failure caused by xylem cavitation leading to cessation of water flow in tissues, desiccation, and cellular death. Further studies are needed to confirm these preliminary conclusions.
  • Öğe
    Genetic variation in Tertiary relics: The case of eastern-Mediterranean Abies (Pinaceae)
    (Wiley, 2017) Hrivnak, Matus; Paule, Ladislav; Krajmerova, Diana; Kulaç, Şemsettin; Şevik, Hakan; Turna, İbrahim; Gomory, Dusan
    The eastern-Mediterranean Abies taxa, which include both widely distributed species and taxa with minuscule ranges, represent a good model to study the impacts of range size and fragmentation on the levels of genetic diversity and differentiation. To assess the patterns of genetic diversity and phylogenetic relationships among eastern-Mediterranean Abies taxa, genetic variation was assessed by eight nuclear microsatellite loci in 52 populations of Abies taxa with a focus on those distributed in Turkey and the Caucasus. Both at the population and the taxon level, the subspecies or regional populations of Abies nordmanniana s.l. exhibited generally higher allelic richness, private allelic richness, and expected heterozygosity compared with Abies cilicica s.l. Results of both the Structure analysis and distance-based approaches showed a strong differentiation of the two A.cilicica subspecies from the rest as well as from each other, whereas the subspecies of A.nordmanniana were distinct but less differentiated. ABC simulations were run for a set of scenarios of phylogeny and past demographic changes. For A. xolcayana, the simulation gave a poor support for the hypothesis of being a taxon resulting from a past hybridization, the same is true for Abies equi-trojani: both they represent evolutionary branches of Abies bornmuelleriana.
  • Öğe
    Fuzzy rule-based landslide susceptibility mapping in Yigilca Forest District (Northwest of Turkey)
    (Istanbul Univ, Fac Forestry, 2016) Aydın, Abdurrahim; Eker, Remzi
    Landslide susceptibility map of Yigilca Forest District was formed based on developed fuzzy rules using GIS-based FuzzyCell software. An inventory of 315 landslides was updated through fieldworks after inventory map previously generated by the authors. Based on the landslide susceptibility mapping study previously made in the same area, for the comparison of two maps, same 8 landslide conditioning parameters were selected and then fuzzified for the landslide susceptibility mapping: land use, lithology, elevation, slope, aspect, distance to streams, distance to roads, and plan curvature. Mamdani model was selected as fuzzy inference system. After fuzzy rules definition, Center of Area (COA) was selected as defuzzification method in model. The output of developed model was normalized between 0 and 1, and then divided five classes such as very low, low, moderate, high, and very high. According to developed model based 8 conditioning parameters, landslide susceptibility in Yigilca Forest District varies between 32 and 67 (in range of 0-100) with 0.703 Area Under the Curve (AUC) value. According to classified landslide susceptibility map, in Yigilca Forest District, 32.89% of the total area has high and very high susceptibility while 29.59% of the area has low and very low susceptibility and the rest located in moderate susceptibility. The result of developed fuzzy rule based model compared with previously generated landslide map with logistic regression (LR). According to comparison of the results of two studies, higher differences exist in terms of AUC value and dispersion of susceptibility classes. This is because fuzzy rule based model completely depends on how parameters are classified and fuzzified and also depends on how truly the expert composed the rules. Even so, GIS-based fuzzy applications provide very valuable facilities for reasoning, which makes it possible to take into account inaccuracies and uncertainties.
  • Öğe
    Forest mapping against rockfalls on a regional scale in Inebolu of Turkey
    (Istanbul Univ, Fac Forestry, 2017) Aydın, Abdurrahim; Eker, Remzi
    Determining areas where forest plantations provide protection against rockfall is significant in the prevention of disasters. In this paper, a case study is conducted in the Ozluce Forest District of Inebolu, Turkey. Potential rockfall source areas are firstly calculated and mapped via RollFree, which uses a digital elevation model as the only input. The rockfall travel distance is then identified using an empirical energy line angle to create propagation maps for different scenarios (using a set of four angles: 28 degrees, 32 degrees, 35 degrees, and 38 degrees). By marking the lower boundaries of propagation, the maximum run-out zone of a fallen block is determined as having a very low, low, medium, or high probability of occurrence (marking the lower boundaries of propagation). These propagation maps are then overlapped with a forest stand map to define areas where the forest provides a protective function against rockfall. According to propagation maps that indicate a high probability of occurrence, only 9% of the total forest area is found to be capable of playing a protective role, whereas for those determined as having a low probability of occurrence, 17% of the forest area provides a protective function.
  • Öğe
    Forest management issues of the southern United States and comparisons with Turkey
    (Tubitak Scientific & Technical Research Council Turkey, 2013) Bettinger, Pete; Siry, Jacek; Cieszewski, Chris; Merry, Krista L.; Zengin, Hayati; Yeşil, Ahmet
    Most of the forest area in the southern United States has been cleared, regrown, purchased, and sold several times over the last 200 years, and forest management practices generally focus on wood production. Agricultural expansion, use, and the abandonment of land have been the major forces behind land use change, and now human population expansion is a major issue. The land tenure system of the United States has allowed individuals and companies to acquire, use, and sell land since the time of European colonization; thus, private ownership of land dominates the southern region. However, new private, corporate, nonindustrial entities have arisen in the last 20 years, mainly as a result of tax policies and changes in industrial business organizations. While in Turkey planning systems are centralized, these systems vary by landowner group in the southern United States. They range from those that are relatively absent (nonindustrial private landowners) to those that are very formal (national forests). The management of forests in the southern United States is also guided by a number of federal, state, and local policies rather than a single enterprise plan, and these policies affect the direction of both public and private forest management. Specifically with regard to public land, the mission and objectives of forestry are similar to those in Turkey, except when considering the needs of local citizens, which has been given greater emphasis in Turkish forest management and planning.
  • Öğe
    Forest Resources and Sawmill Structure of Kosovo: State of the Art and Perspectives
    (Zagreb Univ, Fac Forestry, 2014) Bajraktari, Agron; Petutschnigg, Alexander; Ymeri, Muhamet; Candan, Zeki; Korkut, Süleyman; Nunes, Lina; Pereira, Helena
    Kosovo, located in the heart of the Balkans, was formerly a part of Yugoslavia. The breakup of Yugoslavia led not only to the creation of new countries and borders; it also had a huge impact on the transportation and availability of raw materials and goods. Kosovo's forest products industry has been greatly affected by the country's current political and legal environment. The creation of new boundaries, combined with trade constraints between Kosovo and some neighboring countries, has changed the amount and type of available wood raw material. Although the forest products industry is a very important part of Kosovo's economy, this change in distribution has had a negative impact on the sawmill structure of the country. To better understand the current state of Kosovo's forest products sector, data was collected through a survey of all sawmills in Kosovo and through information gathered from the Ministry of Agriculture, Forestry and Rural Development of Kosovo. In this paper, the forest resources and sawmill structure of Kosovo are analyzed and the availability of different species of wood in different regions of the country is presented. Based on these findings, recommendations are provided for further development of the forest and sawmill industry.
  • Öğe
    FOREST ROAD DESIGN WITH CAD SOFTWARE: A CASE STUDY IN THE WESTERN BLACK SEA REGION OF TURKEY
    (Parlar Scientific Publications (P S P), 2019) Türk, Yılmaz
    It is easier to make the projects and applications of forest roads on the terrain through developed technological tools in today. Road planning and designing by computer aided software is become very demanding task for road engineers. In this study, a total of 14 forest roads within the boundaries of the Bolu Forest Regional Directorate (BFRD) were designed with CAD-based Civil 3D and Plateia software. The suitability of the software was investigated and the obtained field measurements and software results were compared. In addition, the design speed and quality of the forest road design stages of the software were revealed. With them, the design of a 1000-m section for each of the 14 forest roads was carried out. The style database (GDF) was prepared according to the geometric standards of forest road and the drawing style was used during the design stages of the roads. The field Excavation measurements and software excavation values for the 14 forest roads were compared in order to determine the suitability of the Civil 3D and Plateia software. There was no statistically significant difference between the field excavation measurements and software excavation volume values, therefore indicating the suitability of the software for forest road design.