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Öğe A Comparison of Two Felling Techniques Considering Stump-Height-Related Timber Value Loss(Zagreb Univ, Fac Forestry, 2023) Gulci, Nese; Gulci, Sercan; Akay, Abdullah E.; Sessions, JohnHarvest from plantations can provide both industrial wood and forest residues for bioenergy, including stumps. The literature suggests that the choice of cutting system can affect the division between industrial wood recovery and remaining stump volume. In this study, two felling techniques - motor-manual chainsaw and feller-buncher, were compared based on stump-height-related timber value loss for four ground slope classes: high, medium, low, and flat. The economic value loss of wood material for three products - sawlogs, pulpwood, and fiber-chip wood, was determined based on the estimated volume of stumps left in the woods. The results indicated that the average stump height for the motor-manual chainsaw and feller-buncher was 17.16 cm and 8.69 cm. The economic value loss of wood material per stump was higher in felling by manual chainsaw as compared to the feller-buncher operation (log: (sic)0.60 up arrow, paper wood: (sic)0.29 up arrow, fiber-chip: (sic)0.15 up arrow). However, volume loss due to high stumps could contribute to wood for bioenergy if stumps are subsequently removed. Additional research is needed to evaluate the benefits and costs of stump removal for bioenergy as part of a total supply chain to provide both industrial wood and wood for bioenergy.Öğe Estimating the economic value of timber products potentially saved from wildfires by improving forest road standards(Taylor & Francis Inc, 2024) Erkan, Nesat; Akay, Abdullah E.; Bilici, Ebru; Ucar, Zennure; Guney, C. OkanThe aim of this study was aimed to estimate the economic value of timber products from the forest stands that are potentially saved from wildfires after improving road standards. The study was implemented in the Alanya Forest Enterprise Directorate (FED) in the Mediterranean city of Antalya, Turkey. In the solution process, the possible increase in the accessible forest areas with improved forest road standards was investigated by using GIS-based network analysis methods. In the next step, the timber production in the forest areas potentially saved from the wildfire was calculated based on parameters such as site index, rotation period, and stand structure. Then, the economic value of timber product types was calculated using market prices. The results indicated that increasing the design speed on improved forest roads reduced the arrival time of firefighting teams to the forests, which consequently increased the accessible forest areas within the critical response time. It was found that the accessible forest areas within the critical response time increased from 47,231 hectares to 59,354 hectares when standards of the forest roads were improved. This saved 12,123 hectares of additional forest area from the wildfire in the Alanya FED. The cost of road improvement activities was estimated at US$ 2,286,998. It was calculated that the total timber products obtained from the forest area potentially saved was about 94,721 m3, and worth US$7,545,579 at market prices. The results can be used by policymakers in determining the potential investments in improving forest road standards to enhance the efficiency of firefighting activities.Öğe Evaluating Productivity of Small-Scale Cable Yarding System Integrated with a Portable Winch(Zagreb Univ, Fac Forestry, 2023) Akay, Abdullah E.; Gumus, Selcuk; Basaran, AdilSmall-scale forestry operations, which are used in non-industrial and site specific forestry, provide alternative logging methods suitable for precision forestry approach. In this study, a small-scale cable yarding system integrated with a portable winch was considered as alternative timber extraction method compared to a standard tower yarder. It was aimed to evaluate productivity of this yarding method, which was implemented during commercial harvesting activities performed in a 10.74 ha black pine stand located in Bursa province of Turkey. The main factors (i.e. slope, yarding distance, lateral pulling distance, log volume, log length), significantly affecting the productivity, were evaluated based on two slope classes (34-50% and 50-70%) and two yarding distances (100 m and 200 m). The results indicated that the average productivity was 0.95 m(3)/PMH and 0.90 m(3)/SMH. It was revealed that the productivity of the small-scale cable yarding decreased as the ground slope and the yarding distance increased. Statistical analysis indicated that there was a significant (p<0.001) relationship between productivity and log volume and length in four applications. On the other hand, it was found that there was a significant (p<0.05) relationship between productivity and lateral pulling distance in only the first application (34-50% slope; 100 m yarding distance). Considering the volume classes of the logs, it was determined that the productivity increased from the low volume class to the high volume class.Öğe Evaluation of Automatic Prediction of Small Horizontal Curve Attributes of Mountain Roads in GIS Environments(Mdpi, 2022) Gulci, Sercan; Acar, Hafiz Hulusi; Akay, Abdullah E.; Gulci, NeseRoad curve attributes can be determined by using Geographic Information System (GIS) to be used in road vehicle traffic safety and planning studies. This study involves analyzing the GIS-based estimation accuracy in the length, radius and the number of small horizontal road curves on a two-lane rural road and a forest road. The prediction success of horizontal curve attributes was investigated using digitized raw and generalized/simplified road segments. Two different roads were examined, involving 20 test groups and two control groups, using 22 datasets obtained from digitized and surveyed roads based on satellite imagery, GIS estimates, and field measurements. Confusion matrix tables were also used to evaluate the prediction accuracy of horizontal curve geometry. F-score, Mathews Correlation Coefficient, Bookmaker Informedness and Balanced Accuracy were used to investigate the performance of test groups. The Kruskal-Wallis test was used to analyze the statistical relationships between the data. Compared to the Bezier generalization algorithm, the Douglas-Peucker algorithm showed the most accurate horizontal curve predictions at generalization tolerances of 0.8 m and 1 m. The results show that the generalization tolerance level contributes to the prediction accuracy of the number, curve radius, and length of the horizontal curves, which vary with the tolerance value. Thus, this study underlined the importance of calculating generalizations and tolerances following a manual road digitization.Öğe Helicopter Logging Method for Reduced Impact Timber Harvesting Operations*(Forest Engineering and Technologies Platform, 2016) Akay, Abdullah E.; Bilici, EbruTraditional timber harvesting methods can result in serious impacts on vegetation structures, soil properties, and biodiversity in forested areas. Helicopter logging provides important advantages of implementing environmentally friendly harvesting techniques. However, the cost of helicopter logging can be much higher than that of ground-based logging due to high equipment costs, maintenance costs, the cost of flight crew, and fuel costs. Thus, the helicopter logging operation should be carefully planned to implement cost effective and environmentally friendly logging operations. In this study, the stages of helicopter logging and operational factors were first described, and then the operation cost, environmental concerns, and safety practices in helicopter logging were discussed. It can be concluded that the helicopter logging can be effectively used for extraction of timbers especially from environmentally sensitive areas where road construction and logging operations are restricted. In fact, helicopter logging may be the only option to solve timber extraction problems in difficult terrains with steep slope.Öğe Importance of geotechnical soil properties for precision Forest activities in a karst area(Elsevier, 2024) Dindaroglu, Turgay; Vermez, Yasin; Gundogan, Recep; Yakupoglu, Tugrul; Gunal, Hikmet; Akay, Abdullah E.Some soil behaviors change significantly as water content varies over time. The particle size distribution of soils has a direct impact on mechanical properties such as soil water content, resistance to dispersion, swelling-shrinkage, fluidity, plasticity, and stickiness. This study was conducted to investigate the usability of Atterberg limits, consistency index and coefficient of linear extensibility (COLE) in the temporal planning of ecosystem restoration activities such as silvicultural interventions, tillage, afforestation, and the construction of forest roads, etc. Surface soil samples were collected from the sections numbered 263, 264, 266, 268, 317, 318, 319, 323, 324,325 and 366 of the degraded forest of the And & imath;r & imath;n forestry operations department. The COLE, liquid limit (LL), plastic limit (PL), plasticity index and consistency index values of soil samples were determined. The LL values ranged from 17.5 to 62.4%, the PL values from 8.2 to 46.8% and the PI values from 6.4 to 15.5. The highest COLE value (0.13) was recorded in the section 318, while the lowest COLE value (0.03) was in section 325.The LL and PL values have a positive linear relationship with clay and organic matter content. All sections have karstic characteristics, but the mechanical characteristics of the soils differ significantly between the sections. Silvicultural interventions carried out especially in section 318, which had the lowest consistency index (Ic = 0.70), and sections 263, 264, 317 and 319, where the consistency index is >2,should take mechanical properties into account, and the planting time intervals should be determined, accordingly for sustainable forestry.Öğe Mapping the probability of Forest fire in the Mediterranean region of Türkiye using the GIS-based fuzzy-AHP method(Taylor & Francis Inc, 2025) Ucar, Zennure; Guney, Coskun Okan; Akay, Abdullah E.; Bilici, Ebru; Erkan, NesatForest fires have increased in frequency, intensity, and extent significantly worldwide due to climate change and human activities, particularly in the Mediterranean region. Fire-prone areas should be determined primarily to take precautions against forest fires and reduce their ecological, economic, and social impact. This study aimed to determine the spatial distribution of forest fire probability for the Antalya Regional Directorate of Forestry (RDF), highly vulnerable to forest fires. The forest fire probability map was generated using the GIS-based Fuzzy-AHP method, prioritizing decision criteria, including stand characteristics, topographic features, meteorological parameters, and proximity to anthropogenic structures. The results indicated that the most important factors influencing the fire were tree species, development stage, and proximity to road networks. The generated map showed that 45.82% of the forests in Antalya RDF were in the very high class, while 15.82% were in the high-level class. The fire probability map, validated using the Area Under Curve (AUC) method, offered promising and acceptable results above 0.7. The Fuzzy-AHP method, when integrated with GIS techniques, effectively predicts fire probability levels in fire-sensitive forests. This method will empower fire managers to develop and implement strategies that enhance forest fire resilience by predicting areas with high fire probability.Öğe Multispectral UAV and satellite images for digital soil modeling with gradient descent boosting and artificial neural network(Springer Heidelberg, 2022) Dindaroglu, Turgay; Kilic, Mirac; Gunal, Elif; Gundogan, Recep; Akay, Abdullah E.; Seleiman, MahmoudSensor technology and machine learning (ML) enable rapid and accurate estimation of soil properties. This study aimed to estimate some soil characteristics with different ML algorithms using unmanned aerial vehicle (UAV) and Sentinel 2A optical satellite images. Four spectral indices and soil data were statistically compared to assess the performance of estimation. The ML algorithms including Multi-Layer Perception Artificial Neural Network (MLP-ANN) and Gradient Descent Boosting Tree (GDBT)ML were employed to improve the estimation. Bayesian optimization was used to optimize the hyperparameters of the GDBT ML algorithm. The relationships between vegetation indices calculated using the UAV and Sentinel 2A (S2A)satellite images were examined. Total of 122images were taken for 1.66 ha land with a spatial resolution of 3.99 cm. The Green Normalized Difference Vegetation Index (GNDVI), Normalized Difference Vegetation Index (NDVI), Modified Soil Adjusted Vegetation Index (MSAVI), and Transformed Soil Adjusted Vegetation Index (TSAVI) from UAV in rangeland and olive orchards were highly correlated with the same vegetation indices calculated using the S2A image. The RMSE values improved between 23.23 and 35.66% for sand, silt and soil organic matter content in MLP-UAV networks, while the MLP-S2A networks provided 9.73 to 19.85% improvement for pH, clay and soil moisture (SM). The RMSE values in UAV-based GBDT ML algorithms were more successful in estimation of pH, sand, silt, CaCO3, and SM than the S2A models and the relative improvement was between 12.16 and 93.66%. The results showed that (i) estimation success is affected by the spectral response of the soil property as well as statistical characteristics of the observation values, (ii) different optimization techniques as well as the estimation algorithm affect the estimation accuracy, (iii) land use types play an important role in the estimation variance, and (iv) the estimation performance of UAV based models is compatible with the S2A.Öğe Productivity Analysis of Chute System integrated with Portable Winch and Synthetic Rope for Uphill Logging Operation(2017) Gülci, Neşe; Akay, Abdullah E.; Erdaş, Orhan; Acar, H. HulusiTimber extraction activities are generally conducted by using traditional logging methods that involve little or no mechanization. In recent decade, plastic chute systems have been employed as alternative method during timber extraction. There is an increasing interest in implementing chute system because this alternative method reduces the value and volume loss of timber and minimize the total time of logging operation. Even though chute system had been used to extract small size timber in the early times, it has been employed to transport large size logs in recent years. In previous studies, chute system was analyzed during downhill transportation of wood products by gravity force. In this study, chute system integrated with portable winch was developed to haul large logs uphill direction. Besides, synthetic rope was used instead of steel rope in order to reduce weight of the system. The chute system was tested in a harvesting operation take place in Çınarpınar Forest Enterprise Chief in the border of Kahramanmaraş Forest Regional Directorate in Turkey. Productivity of the uphill logging operation was examined for three chute distances (36 m, 48 m, 60 m) at three ground slope classes (30%, 50%, 70%). The results indicated that the highest productivity $(7.00m^3/hr)$ was reached at the shortest chute system with 30% slope. The main factors that affect productivity was total time of winching logs uphill within chute system. It was found that chute system integrated with portable winch was more economic, practical, and efficient method comparing with traditional logging methods.Öğe USING GIS TECHNIQUES FOR MODELING OF ANTHROPOGENIC NOISE PROPAGATION GENERATED BY A CHAINSAW IN FOREST HARVESTING(Croatian Forestry Soc, 2022) Akay, Abdullah E.; Acar, H. Hulusi; Kalkan, BuseNoise is an environmental pollution that negatively affects human health and reduces the performance of employees. Forest harvesting activities are one of the working environments where noise effect is intense. The most common equipment used in forest operations is chainsaw whose noise affects not only the operator but also the wildlife in the territory. The noise maps showing noise propagation can be effectively used in evaluating and controlling the noise effects. In this study, it was aimed to measure the anthropogenic noise levels resulting from the chainsaw used in tree felling and to map its noise propagation with SPreAD-GIS (System for Prediction of Acoustic Detectability) which is a GIS (Geographical Information Systems) based noise prediction software. The study was conducted in Karacabey Flooded Forest within the city of Bursa in Tiirkiye. The results indicated that the average noise level from the chainsaw was above the danger limit (90 dBA) that causes increased physiological reactions and headache on the workers. According to the noise propagation map, the noise exposure of the employees exceeded the warning limit (85 dBA) and the maximum noise level was 95.96 dBA during the harvesting activity. In some parts of the study area, the noise level was 45 dBA or above, causing negative effects on bird species. It can be concluded that the noise maps can be effectively used to determine noise propagation generated by a chainsaw and evaluate the noise effects on the operators and as well as on the bird species in the perimeter.
