Orman Mühendisliği Bölümü Yayın Koleksiyonu

Bu koleksiyon için kalıcı URI

https://hdl.handle.net/20.500.12885/1717

Listeleniyor 1 - 20 / 151

Forest Fire Risk Mapping by using GIS Techniques and AHP Method: A Case Study in Bodrum (Turkey)
(2019) Akay, Abdullah Emin; Şahin, Halil
In Turkey, forest areas located along the coastline of the Marmara, the Aegean and the Mediterranean regions are very sensitive to fire. As a result of forest fires, about 10000 hectares of forest area is damaged annually. One of the key elements in firefighting is early detection and quick intervention. In order to achieve this goal, first of all, the forest areas with fire risk should be determined especially for fire sensitive forest areas. The forest fire risk can be evaluated considering various risk factors such as stand structures, topographic factors, proximity to some features (roads, settlements, and water resources), and climatic factors. In this study, GIS techniques and Analytic Hierarchy Process (AHP) method was used to produce forest fire risk map for the first degree fire sensitive forest land located in Bodrum province of Muğla in Turkey. The results indicated that 11.83% and 21.98% of the forest area was categorized as very high and high fire risk, respectively, while 22.28% and 25.93% was moderate and low fire risk, respectively. The fire risk was found to be very low at the rest of the study area (17.98%). To compare the fire risk map with actual forest fire occurrences in the study area, it was overlapped with the fire map indicating forest components where previous forest fires (>1.0 ha) occurred in the study area in last five years. It was found that 38.32% of the areas damaged by the previous fires were categorized as high and very high fire risks zones in fire risk map, while 28.44% was moderate fire risk zones. The result showed that tree species was the most effective risk factor, followed by tree stages and proximity to water resources. This study revealed that the combination of GIS techniques and AHP method is very advantageous approach to map forest areas with fire risk in short time.
Using GIS Techniques for Modeling Noise Propagation from Mechanized Harvesting Equipment
(2019) Akay, Abdullah Emin; Acar, H. Hulusi
The noise is a kind of environmental pollutions that affects human health and decreases performance of people, education, and home life. Harvesting activities in forestry are one of working environments where noise effect is very intense. Noise is an element of environmental pollution that is effective on human health and needs to be controlled. To evaluate the noise effect, maps of noise propagation are used. The noise map is defined as numerical model of noise sources. The changes in sound level determined by measurements in certain points are shown in noise map. Noise maps are used in calculation of average sound level if it is within acceptable limits and in determination of risky areas where employees are adversely effected. Computer-aided systems have been used in modeling noise propagation in recent years. SPreAD-GIS is free program developed to estimate acoustic effects of anthropogenic noise propagation and adapted to ArcGIS software. In this study, it was aimed to introduce SPreAD-GIS program that can be used to model noise propagation caused by mechanized harvesting equipment. In addition, main factors affecting noise propagation in forest (elevation, land use type, temperature, humidity, wind direction and intensity, climate and weather conditions) were evaluated.
Productivity Analysis of Timber Skidding Operation with Farm Tractor
(Forest Engineering and Technologies Platform, 2018) Gölci, Sercan; Böyöksakall, Halit; Ta, Nanç; Akay, Abdullah Emin
Farm tractors equipped with necessary attachments have been widely used in skidding of forest products in Turkey. There are farm tractors of different types and sizes used in forest operations. For appropriate logging plans and better machine selections in mechanized forest operations, it is important to analyze the efficiency of farm tractors during skidding operations. In this study, it was aimed to analyze the productivity of timber skidding operation with farm tractor. Time study was used to estimate productivity and then the effects of specified factors (volume and number of piece) on productivity were investigated by using statistical analysis. Logging operation took place in a black pine (Pinus nigra) stand located in the province of Köyce?iz in Mu?la. Time data of work stages (i.e. move-out from landing to stump unloaded, choker setting at the stump, skidding loaded from stump to landing, and unloading at the landing) during uphill skidding operation were collected for two skidding trails with different slope classes (20% and 30%) while average skidding distance was kept constant at 100 m. It was found that the average productivity for two slope classes were 5.72 m3/hr and 4.30 m3/hr, respectively. The results indicated that the productivity increased as the volume of skidded logs per turn increased for both slope classes. On the other hand, increasing number of pieces transported in each turn caused reduction in productivity of skidding operation by farm tractor. The most time consuming work stage was skidding followed by move-out unloaded and choker setting stages. © 2021 Complex Issues of Cardiovascular Diseases.
First report of Diplodia sapinea on Cedrus libani in Turkey
(John Wiley and Sons Inc, 2018) Oskay F.; Lehtijaervi, Asko Tapio; Dogmuş-Lehtijärvi H.T.; Woodward S.
Cedar of Lebanon (Cedrus libani) is an ecologically and economically important conifer with a natural distribution in southern Turkey. Currently, no serious diseases affect C. libani in its native range, although it is susceptible to pathogens such as Heterobasidion annosum and Diplodia pinea in inoculation experiments (Lehtijärvi et al., 1). Recent reports from the Balkans and Northern Europe, however, suggest that C. libani is susceptible to foliage and shoot diseases such as Diplodia pinea, Dothistroma septosporum and Sirococcus tsugae (Mullet et al., 2; Zlatkovic et al., 2016).
Effects of Improving Forest Road Standards on Shortening the Arrival Time of Ground-based Firefighting Teams Accessing to the Forest Fires
(Forest Engineering and Technologies Platform, 2021) Akay, Abdullah Emin; Podolskaia, Ekaterina S; Uçar, Zennure
In fighting against forest fires, it is crucial for the ground-based firefighting team to reach a fire area in critical response time in which the chance of controlling the fires is significantly high. Road networks are the key infrastructures that provide access to the forest areas for the protection of forest resources. In order to benefit from this important function of roads, especially in forested areas with high natural forest fire risk, they should be built in with adequate technical road standards since the low standards limit the fire truck speed that increases the arrival time of the firefighting team to the fire areas. Most of the forest roads in Turkey are Type-B secondary forest roads with low technical road standards (road width, curve radius, surface materials) that limit the speed of fire trucks. This paper aimed to evaluate the potential contribution of improving the standards of Type-B secondary forest roads in terms of increasing accessible forested areas in critical response time in the case of forest fire occurrence. The study area was Kahramanmaraş Forestry Enterprise Directorate (FED), where forests are sensitive to forest fires at the first degree. In the solution process, firstly, accessible forest areas by the firefighting teams located in the study area (six teams) according to the critical response time were determined by considering the existing road network in the study area. In the second scenario, the possible increase in the accessible forest areas with improved forest road standards and increased travel speed in forest roads was investigated. The results indicated that the areas that can be reached promptly by the firefighting teams in critical response time were 21% and 44% for considering existing roads and improved roads in the whole study area. On the other hand, the accessible forested areas in critical response time increased from 17% to 36% when standards of the forest roads were improved. It is indicated that improving road standards has a significant value to contribute the efficiency of firefighting activities if the practitioners implemented presented methodology.
Integrated Planning of Timber Extraction and Hauling Activities by using Network 2000 Program
(Forest Engineering and Technologies Platform, 2021) Akay, Abdullah Emin; Şeşen, Nedim
Planning of forest transportation is a complex problem that requires effective and harmonious design and implementation of various forest operations including extraction, loading, and hauling of forest products. These operations constitute a significant part of the total cost of producing forest products; therefore, developing the most appropriate (minimum cost/maximum net profit) transportation plan has increasing importance for the economic aspect. Computer-aided models can be used to plan the transportation of forest products and systematically searching for the most suitable solution. In this study, a network analysis-based Network 2000 program was used to determine the optimum routes with minimum forest operation costs and maximum net profit of forest products considering two logging truck types (medium and large size). In the solution process, two farm tractors (4x2 and 4x4) for extraction operation and two loaders (tracked and rubber-tired) for loading operation were evaluated. The alternative with the minimum cost was determined using the Network 2000 program. The study was implemented in Kınık Forest Enterprise Chief (FEC) located in the city of Bursa in Turkey, while considering five landing areas where various forest products (i.e. log, mine poles, industrial wood, and paper wood) were extracted from the six harvesting units and hauled to two forest depots. In the study, the optimum solution was searched for two scenarios where only the forest depot which is commonly used in the Kınık FEC was considered in the first scenario while the forest depot of the neighboring enterprise in the region was also evaluated in the second scenario. The results obtained from the first scenario indicated that using large-size tractor reduced the hauling cost by 8% which led to over 1000 TRY reduction in the total cost of forest operations. The hauling cost and total forest operation cost obtained in the second scenario was about 16% and 2% less than that of the cost obtained in the first scenario for the case of large-size truck. On the other hand, total net profit of the forest products received in the second scenario was about 35000 TRY more than that of the net profit received in the first scenario for the case of large-size truck. The optimum farm tractor for skidding operation was successfully selected by the Network 2000 program considering terrain conditions in the harvesting unit and availability of the equipment. Likewise, optimum loader was also determined by considering distribution of the forest products on the landing areas.
Noise Reduction Provided by Trees in an Urban University Campus*
(Forest Engineering and Technologies Platform, 2021) Taş, İnanç
In urban universities, there are various noise sources such as roads, railways, construction activities that disturb staffs and students and cause undesirable environment for higher education. In this study, noise reduction effects of trees were investigated in the urban campus of Bursa Technical University (BTU) located in Yıldırım province of Bursa, Turkey. The campus was surrounded by a major inter-city road with a heavy traffic at the north and there is a large hospital at the south. There is a tree fence along the north boarder and there are groups of trees particularly at the north. In field study, the peak noise level data were collected for 5 minutes in two periods (Morning: 09:00-11:00 and Afternoon: 14:00-16:00) from total of 64 points which were homogenously distributed in the campus. Additional noise data were also collected from outside and inside of tree fence along the north border and from midpoint of each tree group. The coordinates of the noise data points were recorded by a GPS and a noise level layer was generated in ArcGIS 10.4.1. Then, noise map of campus was generated using kriging function based on spatial interpolation of noise data. The results indicated that the average peak noise level was 65.6 dBA in the morning period and 66.1 dBA in the afternon period. The maximum peak noise level of 103.6 dBA was reached in the morning period, while maximum peak noise level was 101.6 dBA in the afternoon period. The average peak noise level within the tree groups were 53.7 dBA (maximum 59.3 dBA) and 54.1 dBA (maximum 61.3 dbA) in two periods, respectively. It was also found that tree fences reduced the noise level by 24.9 dBA and 26.3 dBA in two periods, respectively. The results revealed that trees within urban campus are important to reduce noise effect.
THE IMPACT OF URBAN POPULATION CHANGE ON FORESTS, IN-FOREST RECREATION AREAS AND URBAN FORESTS IN TURKEY
(CORVINUS UNIV BUDAPEST, 2022) Köse, Murat
This study aimed to investigate the effects of rapid population growth and urbanization on forests, in-forest recreation areas and urban forests in Turkey. Therefore, through the consideration of the urban population changes in Turkey between 1973-2019, "Forestry Statistics" related to the changes in the forest existence, in-forest recreational areas and urban forests were evaluated. Within the scope of "Forestry Statistics", both forestry data and population data were considered separate variables, and 36 variables were created in this context. According to this, while the total forest area in Turkey was 20,199,296 ha in 1973, it increased by 2,541,001 ha (12.6%) and reached 22,740,297 ha by 2019. According to the up-to-date data, there have been increases in growing stock and annual current increment, as well as forest areas in Turkey. It is a fact that there is a transformation in favor of forests in rural areas of the country. However, it is not possible to talk about a similar situation in urban areas. Although there is a positive correlation between the urban population and forest presence across the country, it is not at the same rate. The urban population increases several times faster than the extent of forest areas and growing stock.
ASSESSMENT OF FIREFIGHTING FACILITIES AND ROADS REGARDING WITH FIRE-RESISTANT FOREST PROJECT (YARDOP)
(EDITURA UNIV, 2019) Bilici, Ebru; Gencal, Burhan; Taş, İnanç; Akay, Abdullah Emin
As a result of natural disasters such as fire, storms, avalanches etc., natural resources have been destroying rapidly in the world. Due to global warming and other factors, forest fires result in serious damages on forest resources in arid regions. Therefore, firefighting activities should be well planned and special attention should be paid to grow fire-resistant forest in the regions with high fire risk. For this purpose, firefighting facilities (i.e. fire breaks, fire lines) and roads for the purpose of fire protection and fire-fighting should be specially evaluated in these regions. Road networks are effectively used during and after a fire and are also used to stop the fire. In this study, the firefighting facilities and roads developed for fire intervention within the Fire- Resistant Forest Project (YARDOP) have been evaluated. Within the project, firefighting facilities have been planned to build a fire-resistant stands. These firefighting facilities can also be used for firefighting purposes. This study indicated that the standards of firefighting facilities and roads used in YARDOP projects are likely to be an alternative solution for many countries, especially in the Mediterranean countries and generally in the same environmental conditions around the world.
EXTRACTION OF RESINOUS ROOT WOODS AS AN ALTERNATIVE SOURCE OF RESIN IN TURKEY
(EDITURA UNIV, 2019) Akay, Abdullah Emin; Taş, İnanç; Gencal, Burhan; Bilici, Ebru
To meet increasing market demands on resin raw material and its derivatives leads to the search for new alternative sources. The resin, which is generally produced by opening the wounds on the standing trees, can be produced by extracting from the root parts of the trees. Especially after the pine trees are cut, there is a high accumulation of resin in the stump on the soil surface and the root parts under the soil. These parts of the trees that are left under the soil surface are called resinous root wood and in recent years its importance as an alternative source of resin production is increasing in Turkey. In this study, technical information about pine root wood and its extraction was given and methods of producing resinous root wood were presented. The information obtained from forest service was evaluated in terms of marketing of resinous root wood. It is anticipated that the production of resinous pine root wood will be promising alternative source of resin raw material with the arrangements that can be made to provide alternative job opportunities to the local people in rural areas.
The Effects of Windthrow Damage on Soil Properties in Scots Pine, Black Pine and Kazdagi Fir Stands in the Northwest Turkey
(Kastamonu Üniversitesi, 2021) Savaci, Gamze; Sarıyıldız, Temel; Caglar, Sadik; Kara, Ferhat; Topal, Esra
Aim of study: The short-term effects of windthrow damage on soil properties were investigated in Kazdagi fir (Abies nordmanniana subsp. equi-trojani), Scots pine (Pinus sylvestris L.) and black pine (Pinus nigra Arnold.) stand in northwest Turkey. Area of study: The study was carried out in Kastamonu and Sinop regions. Material and methods: In order to understand the effects of windthrow damage occurred in 2013, soil samples were collected at a depth of 0-30 cm from the disturbed and undisturbed sites in 2018 (5 year later), and analyzed for soil physical and chemical properties. Main results: The increases in temperature, wind speed and heavy rainfall in the study sites seemed to result in the windthrows. There were significant differences in soil physical and chemical properties among the three tree species, and also between the disturbed and the undisturbed sites. Highlights: After the windthrows, increased SOC and TN stocks, P and K could be related to the accumulation of organic matter. However, we were not able to identify a single mechanism to explain this observed relationship. Thus, the root-soil interactions of the three tree species should be conclusively examined in future studies in order to define the relationships between soil chemical properties and root features.
SOME MEDICINAL - AROMATIC PLANTS SOLD IN HERBALISTS OF ORDU PROVINCE IN TURKEY AND THEIR USAGE
(HEALTH & ENVIRONMENT ASSOC, 2021) Karaevli, Asiye; Sarıkaya, Ayşe Gül
In this study, 17 herbalists from the center and some districts (Korgan-Kumru-Fatsa-Unye) of Ordu province were interviewed in order to determine the medicinal and aromatic plants sold in herbalists in Ordu province and their usage areas. As result of the interviews, it was determined that 35 taxa belonging to 19 families and they have 20 different usage areas Families with the most used species were Lamiaceae (20%), Apiaceae (11%), Rosaceae (8%) and Fabeceae (8%). Using parts of this taxa are leaf (37%), seed (17%), flower (17%), fruit (14%), root (5%), shell (3%) and the stem (3%). It has been determined that taxa are consumed as brewing (52%), raw (20%), powder (15%), oil (9%) molasses (2%) and boiling (2%). The species mostly sold in the herbalist shops were distinguished as Ginger (Zingiber ofinale R.), Turmeric (Curcuma longa L.), Chili pepper (Capsicum annum L., Black pepper (Piper nigrum L.), Mint (Mentha piperita L.) and Thyme (Tymus spp.). Medicinal and aromatic plants are mostly used as flu, cold, upper respiratory tract ailments, slimming-edema remover, spice, strengthening the immune system and relieving intestinal disorders.
THE EFFECT OF FOREST FIRES ON WILDLIFE AND HABITAT RESTORATION AFTER FIRE
(TÜBA, 2021) Gündoğdu, Ebubekir; Sari, Uyesi Alptug; Kavzoglu, T
Every year, forests are exposed to more fire risks with the effect of global climate change. The Covid-19 pandemic, which has been experienced in recent years, has changed the perspective of human beings towards nature, and the needs and demands of people living in cities to use nature have increased day by day. When these two elements come together, it is inevitable that the risk of fire will increase in fire-sensitive ecosystems. One of the living groups most affected by this situation is wild animals. In the burned areas, not only the tree communities but also the entire forest ecosystem has been damaged. In particular, wildlife is adversely affected by fires in the short term, and hundreds of wild animals die. Therefore, rehabilitation and restoration of forests after fire emerges as an element that should be planned together with wildlife in terms of the sustainability of forest ecosystems. For this reason, all burned areas should not be renewed with the same method and decision mechanism, and decisions specific to the wildlife and habitat should be taken.
Some morphological characteristics and phenological stages of crataegus Monogyna Jacq. Var. Monogyna according to the BBCH scale
(Parlar Scientific Publications, 2021) Sarıkaya, Ayşe Gül; Guclu, Sultan Filiz
This study was performed to determine several morphological and phenological properties of the Crataegus monogyna Jacq. var. monogyna, which is naturally distributed in Atabey, a district rich in biodiversity. Morphological characteristics of leaves, such as size, breadth, stalk length, number of lobes and fruit size, diameter, and weight. Inflorescences have been measured in order to determine the morphological characteristics. Phenological growth stages were recorded by observations according to the Bundesanstalt, Bundessortenamt and Chemical Industries (BBCH) scale. Statistical analyses were performed with generalized linearized models using SPSS. When morphological characteristics were examined, the Atabey2 genotype could be considered as hopeful in terms of fruit weight, width and diameter. Determination of the stages of phenological development of Crataegus taxa, which has an important place as a non-wood forest product, according to the BBCH scale, has importance in terms of understanding the collection time of plant organs to be evaluated and supervising collection and sustainability. This study was the first one in which the BBCH scale was used in the analysis of the phenological development of the Crataegus monogyna Jacq. var. monogyna.
IDENTIFICATION OF CURVATURE RADIUS FOR CURVED SECTIONS ON FOREST ROADS IN THE PROCESS OF UTILISATION
(Transilvania University of Brasov 1, 2021) RUDKO I.; BAKAY B.; Akay, Abdullah Emin; BARYLIAK V.; HORZOV S.
This article reviews the problem of measuring the actual radius of curvature for curved sections of existing forest roads, as forestry enterprises require reliable technical information about the current conditions of operated transport networks. It was identified that at this moment, a selection of methods are used for measuring the radii of horizontal curved sections of roads, which have certain advantages and disadvantages in specific natural production conditions. For calculating the radius of curvature for auto forest road projects it is recommended to apply the method of measured angles by chord angle deviation, which is sufficiently accurate for engineering purposes and does not require usage of special high-precision equipment and tools.
Maxent modeling for predicting the potential distribution of Arbutus andrachne L. belonging to climate change in Turkey
(University of Kuwait, 2021) Sarıkaya, Ayşe Gül; Orucu, Omer K.
Arbutus andrachne L., the strawberry tree, is an evergreen shrub or small tree in the Turkish flora and has broad uses. The wood is used for decorative purposes, packaging, and manufacturing furniture. The fruits are edible and used in treating many kinds of diseases. However, global warming might affect the abundance of this symbolic plant's distribution, especially at higher latitudes. This study was conducted to determine the expected effects of climate change on A. andrachne. For this purpose, Representative Concentration Pathway (RCP) 4.5 and RCP 8.5 were used to expect climate change scenarios for 2050 and 2070, and potential distribution areas of A. andrachne were presented. The results indicated that the distribution of A. andrachne would decrease in the southern regions of Turkey. However, the spread of the species could be expanded in the western and northern areas. It is also expected that there would be potential habitat losses, which would affect the distribution of A. andrachne.
Evaluating the effects of improving forest road standards on economic value of forest products
(University of Zagreb, Faculty of Political Sciences, 2021) Akay, Abdullah Emin; Serin H.; Sessions J.; Bilici E.; Pak M.
Forest roads are the key infrastructures that provide access to forest areas for sustainable management, protection, and utilization of forest resources. In order to benefit from the important functions of forest roads, they should be built in with adequate technical road standards. The road network with low technical standards require more frequent major repairs to ensure continues access to forest resources. In addition, only small trucks with low load capacity can move on the low standard roads. Furthermore, the low road standards limit the truck speed that increases vehicle travel time. These negative effects increase the transportation costs which are an important part of the timber production costs in Turkey. Thus, improving the road standards and developing forest transportation planning should be evaluated together in the most appropriate way. Large logging trucks with high load capacity are generally preferred for efficient transportation of wood-based forest products. In Turkey, large logging trucks, however, cannot operate on the most of the forest roads because insufficient technical road standards (road width, curve radius, surface materials, road structures) limit the maneuverability of large logging trucks. In this study, the objective is to determine the effects of improving forest road standards on total net profit of forest products by using the NETWORK 2000 program, a heuristic approach for solving forest transportation problems. Three Forest Enterprise Chiefs (FECs) located in Mustafakemalpaşa Forest Enterprise Directorate (FED) in Bursa Forest Regional Directorate were selected as the study area. The digital data layers for forest road network was generated by using ArcGIS 10.4 software. In the solution process, firstly, the optimum routes that minimize the transportation cost and maximize the total net profit of forest products on existing forest road networks were investigated for a truck type (15 ton) currently used in the region. In the second case, forest transportation was planned for the high load capacity truck (29 ton) moving on the forest roads with improved standards. In the first case, the transportation costs and annual major repair costs were considered in the calculation of the net profit of forest products, while one time cost of road improvement activities (i.e. road improvement construction, road structure installation, road surface construction) and annual maintenance costs were considered along with transportation costs in the second case. In both cases, the costs of other forest operations (i.e. felling, logging, etc.) were not considered since it was assumed that they do not vary with the forest transportation alternatives. As a result of the transportation plan developed for high load capacity truck, the annual transportation cost decreased by 46.85% comparing to the local logging trucks with low load capacity. Using improved road standards, the total road costs computed for the time period of 30 years (i.e. the average expected life cycle of forest roads) were reduced by 4.64%. The total net profit of forest products transported by using a high load capacity truck was 473 340 Euro more than that of using low load capacity truck on the existing forest road network. Thus, improving road standards might result in some additional costs in the road construction stage, but total net profit of forest products increase since transportation costs along with maintenance and repair costs considerably decrease in the long term.
Analysis of a feller-buncher productivity: A case study of whole-tree harvesting from marmara region, Turkey
(Editura Silvica, 2021) Gülci N.; Yüksel K.; Serin H.; Bilici E.; Akay, Abdullah Emin
In fully mechanized forest harvesting systems, tree felling activities are mostly performed by using harvesters or feller-bunchers. In some regions of Turkey, where terrain conditions and stand characteristics are suitable, fully mechanized harvesting systems have been recently practiced by some of the logging contractors as private forest industry demands for large amounts of forest products throughout the year. Thus, performances of these newly practiced harvesting systems should be carefully analyzed in order to implement productive and cost-effective mechanized harvesting systems. In this study, productivity of whole-tree harvesting using a feller-buncher was investigated based on stand parameters including tree height, DBH, and volume. The DBH of the felled trees were divided into four classes (i.e. very small: 16-19 cm, small: 20-23 cm, medium: 24-27 cm and large: 28-31 cm) to investigate the effects of various DBH class on the time consumption of cutting stage and productivity of the feller-buncher. To estimate productivity of feller-buncher in harvesting operation, multiple linear and polynomial regressions were also developed and discussed after the interpretation of diagnostic plots. The results indicated that the average productivity of the feller-buncher was 74.96 m3/h which was closely related with tree height (r = 0.63), DBH (r = 0.67), and volume (r = 0.67). The average moving time was the most time-consuming stage (60%), followed by cutting (29%) and bunching stages (11%). It was found that DBH classes caused statistically significant (p < 0.05) effects on the time spent on cutting stage and productivity of the feller-buncher. The cutting time and productivity increased from very small to large diameter classes, while bunching time increased from very small to small diameter and then medium diameter to large diameter classes. Polynomial regression had a positive impact on the performance of the estimation model of manually field-measured data based on the error parameters.
A model for urban forest management planning: Istanbul case study
(Gheorghe Asachi Technical University of Iasi, Romania, 2021) Köse, Murat; Kirca S.; Gürbey A.P.; Saglam S.; Cinar H.S.
Urban forests have become important elements of cities' green fabric providing many ecosystem services including recreation. In this study, we proposed a model for urban forest management planning in the example of Istanbul, where urban sprawl has transformed the green infrastructure of the city dramatically. To this purpose, a total of 201 surveys were conducted through face-to-face interviews including those working as managers and technical staff in the forestry organization in Istanbul, academicians and NGOs. Subjects to be surveyed were determined according to the layered-simple random sampling method. The data were evaluated by descriptive statistics based on a variety of opinions about urban forest management planning in Turkey along with various socio-economic variables (gender, profession and experience). Whether there was any statistically significant difference between the groups was determined by Kruskal-Wallis H-Test. In case a difference was found, Duncan's Multiple Range Test was applied to detect the group(s) significantly different from each other. The results revealed that mainly males agreed on the purpose of urban forests as addressing recreational and social needs. All groups highlighted the lack of coordination and poor management system as main problems, while experienced and male subjects addressed that a new urban forest law is necessary. Mainly academicians and representatives of NGO's and related institutions suggested redefining the concept and restructuring the legislation concerning urban forests. In terms of activities, the majority favored hiking and sightseeing activities (51%), photography (42%), and extreme sports (37%). There was an emphasis on the need for sufficient number of hiking, climbing and cycling trails and botanical gardens. As a result, a model plan based on sustainable resource management ensuring multi-purpose utilization was proposed.
An assessment of conventional and drone-based measurements for tree attributes in timber volume estimation: A case study on stone pine plantation
(Elsevier B.V., 2021) Gülci S.; Akay, Abdullah Emin; Gülci N.; Taş, İnanç
The use of unmanned aerial vehicles (UAVs) as a useful tool in forestry studies is increasing rapidly. The level of accuracy in UAV-supported measurement data has been increasing in the field of forestry. Recently, biophysical and morphological tree information has been calculated using the three-dimensional (3D) point cloud data. The accuracy of studies on different types of trees (i.e. coniferous and deciduous) may vary depending on the selected instruments and methods. Within the scope of the present study, height (H) and crown projection area (CPA) of 105 stone pines (Pinus pinea, L.) measured using both conventional methods and UAV-based Structure-from-Motion (SfM) derived 3D dense point cloud were evaluated. Tree volumes in the study area were calculated using the allometric formulas generated based on the linear diameter model produced with the field measurements. For field measurements and UAV based data, the tree volumes were calculated using the single- and double-entry over-bark stem volume equations, and their numerical comparisons were conducted. To search for the differences, RMSE (Root mean square error), RMSE% (Root mean square percentage error), MAE (Mean absolute error) and MAE% (Mean absolute percentage error) values were taken into consideration. According to the results of the paired t-test, it was revealed that there were no significant differences between the field- and SfM- measurements based methods. Considering the average values instead of individual (single) trees in the information obtained using the 3D point cloud in such stands gave more accurate results. It was found that forest parameters at plot levels in stands could be quickly revealed by UAV photogrammetry. In addition, these data can be evaluated as a metric measurement technique for sustainable and precise operational planning in forest lands.

Güncel Gönderiler