Browsing by Author "Özel H.B."

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Age-related changes of some chemical components in the leaves of oriental beech (fagus orientalis lipsky.)
(2019-12-01) Turfan N.; Ayan S.; Yer E.N.; Özel H.B.
Background and Purpose: This study presents the analysis of photosynthetic pigments, proline, total soluble protein, total amino acids, glucose, sucrose, total soluble sugars, total amount of phenolic compounds and flavonoids, malondialdehyde (MDA) and hydrogen peroxide (H2O2) concentration in the leaf samples collected from oriental beech trees, which are naturally spread in Kastamonu Province, Turkey, with differing ages, enzyme activities of ascorbate peroxidase (APX), catalase (CAT) and superoxide dismutase (SOD). Material and Methods: The research was carried out on oriental beech trees (Fagus orientalis L.) of different ages located at 1300 m high elevation in Ahlat Village of Kastamonu Province, Turkey. Oriental beech trees of different ages (≥25, ≥50, ≥100, ≥200 and ≥600 years-old) constituted the material of this study. In leaf samples taken from trees of different ages, photosynthetic pigments (chlorophyll a, chlorophyll b, total chlorophyll and carotenoid), proline, total soluble protein, total amino acid, glucose, sucrose, total soluble sugars, the amount of total phenolic compounds and flavonoids, MDA, H2O2 concentration, enzyme activities of APX, CAT and SOD, as well as the relationship between the total content of C, N and H elements and the tree ages were studied. Results: As a result of the research conducted, significant differences were determined in terms of chlorophyll, total phenolic compound, flavonoid, glucose, amounts of sucrose, nitrogenous compounds, proline, total soluble protein, MDA, H2O2 concentrations, and the activities of APX, CAT and SOD in the leaves of oriental beech trees with differing ages. The highest content of chlorophyll a was found to be in the youngest age group of ≥25 years. Total chlorophyll is low in young trees and high in middle-aged, old and very old trees. According to the results obtained, it was concluded that the MDA and H2O2 concentrations in the trees did not vary depending on the age of trees only, but also on the genotype, environmental conditions and metabolic activities. It was concluded that the fact that the total chlorophyll, phenolic compounds and sucrose content in oriental beech trees are high and that MDA content is low could have an influence on the long life of ≥600 years-old oriental beech trees. Conclusions: The activity of photosynthesis is related to leaf characteristics more than the age of trees.
Altitude-dependent Variations in Some Morphological and Anatomical Features of Anatolian Chestnut
(2024-08-01) Özdikmenli G.; Yiğit N.; Özel H.B.; Şevik H.
ANTIOXIDANT VARIABILITY OF THE SEEDS IN CORE AND MARGINAL POPULATIONS OF TAURUS CEDAR (Cedrus libani A. Rich.)
(2018-01-01) Ayan S.; Turfan N.; Yer E.N.; Šeho M.; Özel H.B.; Ducci F.
Genetic diversity is the basis for adaptation and survival of tree species under changing environmental conditions, representing the key issue of stability and productivity of forest ecosystems. In this study, core and marginal populations of Taurus cedar (Cedrus libani A. Rich.) were investigated due to their importance in gene conservation. Assessment of genetic diversity in isolated populations is of great importance for the conservation and improvement programs. Under global climate change conditions, they may possess genotypes of future adaptive potential. The aim of this study is to determine the amount of proline to understand water deficiency stress of the population, total soluble proteins, MDA, H 2 O 2 , α-amylase, the variability of antioxidant as CAT, SOD, APX and GuPX of Taurus Cedar seeds fromfive core populations (Kahramanmaraş-Andırın/Elmadağı (AND), Adana-Pozantı/ Pozantı (POZ), Mersin-Anamur/Abanoz (ANA), Antalya-Finike/Aykırıçay (FIN) and Antalya-Kaş/Karaçay (KAS)) and one marginal provenance (Amasya-Tokat-Niksar/Çatalan (NIK)) in Turkey. According to the results, a significant difference was detected between populations. Significantly higher amounts of proline were detected for ANA (7,46 µmol/g) and POZ (7,22 µmol/g) populations, whereas the lowest amounts of proline were detected in KAS (3,98 µmol/g) population, which represent the optimal distribution of Taurus cedar. This finding indicates that POZ and ANA populations, in the transition zone from Mediterranean region to steppe territory, are more resistant to the frost, than the other populations. The highest α-amilase enzyme amount was detected in POZ population, growing in the optimum range for Taurus cedar. Significantly higher levels of H 2 O 2 were detected in NIK (11,97 µmol/g) and ANA (11,60 µmol/g). This is an indication of higher levels of oxidative stress in the seed samples of these populations. With the present research it’s verified that, enzymes such as SOD, CAT, GuPX and APX, controlling reactive oxygen species (ROS) levels in plant cells, are the elements of the antioxidant defence system functioning as protective mechanisms for plants against stress conditions. From the practical point of view, improvement in afforestation performance can be achieved on the steppe of Central Anatolia Region holding the potential afforestation areas of Turkey, through use of forest reproductive materials from POZ and ANA stands with their higher resistance against stress, and NIK as an isolated and marginal population.
Assessing the possibility of airborne bismuth accumulation and spatial distribution in an urban area by tree bark: A case study in Düzce, Türkiye
(2023-01-01) Isinkaralar K.; Isinkaralar O.; Koç İ.; Özel H.B.; Şevik H.
Heavy metal accumulation has been a hot topic of many studies in recent years, as they are toxic elements that can be highly harmful to human health and the environment. The metal concentrations of some trees used for monitoring air quality give information about the pollutant sources in the ambient atmosphere. In this study, P. pinaster, C. arizonica, P. orientalis, C. atlantica, and P. menziesii were determined to investigate their use as biomonitors for air quality. Metallic bismuth and bismuth compounds, which have been widely used in several industries, have low toxicity to humans, although bismuth toxicity can show over-dosage depending on its application. The variability of bismuth levels in the organs of the species was investigated to explain atmospheric deposition over the years. The bismuth accumulation of C. arizonica and P. pinaster increases depending on time interval. The ascending-descending trend in other species could not be obtained clearly via dry and wet deposition of atmospheric metals. Our analysis reveals that the total deposit (barks and wood) of P. pinaster, C. arizonica, P. orientalis, C. atlantica, and P. menziesii were 134, 115, 94, 131, and 148 mg/kg, respectively, and they have been quite clearly reflected atmospheric bismuth deposition. The bismuth concentration has significantly increased since the 1983 sampling; P. menziesii can be valuable bioindicators for highlighting polluted areas. Compared with the traditional air samplers, the proposed P. menziesii bioindicator is proven to be more effective, low cost, and sustainable and thus has broad application prospects in bismuth concentration.
Clonal Variation Based on Some Morphological and Micromorphological Characteristics in the Boyabat (Sinop/Turkey) Black Pine (Pinus nigra subsp. pallasiana (Lamb.) Holmboe) Seed Orchard
(2023-01-01) Yigit N.; Öztürk A.; Sevik H.; Özel H.B.; Kshkush F.E.R.; Işık B.
Determining the Taxol Contents of Yew Tree Populations in Western Black Sea and Marmara Regions and Analyzing Some Forest Stand Characteristics
(2023-05-01) Tandoğan M.; Özel H.B.; Gözet F.T.; Şevik H.
Yew tree (Taxus baccata L.) is mainly populated in Türkiye, Europe, and Caucasia regions. It has natural anticancer compounds and is a source of raw materials used in modern medicine. The present study aimed to examine the taxol contents of yew trees naturally grown in Marmara and Western Black Sea regions by subjecting needle samples taken from 17 yew populations to extraction and liquid chromatography tandem mass / mass spectrometer system (LC-MS/MS) analysis. It was also examined whether a relationship exists between some stand characteristics and taxoid contents of the needles. From these analyses, the highest taxol contents were found in Bartın-Gölderesi, Yığılca-Kurtkayası, İnebolu-Karagöl, and Yenice-Kızılkaya populations. The statistical analyses showed that there were significant relationships between compound contents and slope, humus content, total nitrogen content (%), and potassium (K). It is recommended to use these derivatives obtained from natural forests in sapling nursing and tissue culture studies, to produce pharmaceutical materials from leaves and protect and improve the current gene sources.
Effect of climate change on potential distribution of oriental beech (Fagus orientalis Lipsky.) in the twenty-first century in Turkey
(2022-04-01) Ayan S.; Bugday E.; Varol T.; Özel H.B.; Thurm E.A.
The rising temperatures and decreasing rainfall are expected to have negative effects on ecosystem services by causing significant shrinkage or shift of forest distribution particularly in Mediterranean basin. In this study, it was aimed to determine the distribution of oriental beech (Fagus orientalis Lipsky.) by modelling the current and future potential locations of the habitats. With Maximum Entropy (MaxEnt) approach, we predicted its distribution under current and future conditions (RCP 4.5 and RCP 8.5) in Turkey. Modelling was performed by using eight bioclimatic variables that show significant relationship to the current distribution of oriental beech and were widely used in the literature. The fitted model had high quality (93.5% AUC) and is biological meaningful. The prediction of warmer condition in future showed that the populations on the southern slopes of the North Anatolian Mountains were expected to shrink and that there would be reduction in the populations found in the main distribution area in the Istranca Mountains and the Northern Anatolia, especially in populations in the transition zone of Central Anatolia. Also, oriental beech would lose its isolated-marginal populations in the southeast of Turkey. The results highlight the importance of a genetic conservation programme for beech population in Turkey. Otherwise, the genetic pools seem to extinct under climate change. Furthermore, the paper is intended to provide a starting point for a monitoring of oriental beech at the edge of its distribution, to observe its climatic migration.
Effects of Melatonin Applications on Anatolian Black Pine (Pinus nigra J. F. Arnold. subsp. pallasiana (Lamb.) Holmboe) Afforestation Performance in Semi-Arid Areas
(2023-01-01) Çelik E.N.Y.; Ayan S.; Özel H.B.; Turfan N.; Yer B.M.; Abdaloğlu G.
Melatonin, a substantial hormone, is a natural antioxidant agent that functions as a protector against the harmful effects of free radicals. Studies have found that "exogenous melatonin" applications have a positive effect on the growth and development of plants. This study investigated the adaptation of the seedlings that were transported from the nursery to the afforestation site for the process of planting. In 2019 the 2+0 aged bare-rooted Kastamonu/Taşköprü Anatolian Black pine seedlings, which are suitable for planting in semi-arid areas, were selected as research materials. Four different doses of “exogenous melatonin" (250, 500, 1000, and 1500 μM) were administered through two different methods (root-dipping and needle-spraying). Morphological seedling characteristics and bioactive chemical variables were measured for the control group and the seedlings treated with different doses of melatonin. Antioxidant enzyme activities were identified. When both the needle-spraying and root-dipping methods for melatonin application were evaluated in terms of morphological and biochemical variables, the best results were determined in low doses (250 to 500 μM). The results suggest that melatonin provides support to the metabolic process for the resistance of seedlings to low temperatures and semi-arid climatic conditions.
Effects of stand types on recreational preferences of society in the Sub-Alpine Zone, northern Turkey
(2022-11-01) Varol T.; Özel H.B.; Kara F.; Çavuş Kara İ.; Ayan S.
The main objective of this study was to examine how different stand types influenced the tendency of visitors for varying recreational activities (i.e., hiking, trekking, camping and hunting) from 1993 to 2018 in the surrounding areas of Uluyayla Natural Recreation Site in Bartin, northern Turkey. A total of 627 visitors were selected on a voluntary basis, and questioned in the form of questionnaire. Most of the participants were in the age of 21–40 years old, and they were mostly (62.4%) male. Most of the participants (82.7%) lived in cities, while 62.8% of them were tourists when visiting the site. In determining the preferences of the visitors regarding the stand types for different recreational activities, several images of each stand were shared with them, and they were asked which stand type they would prefer for a given recreation activity (i.e., hiking, tracking, camping and hunting). A range of options from 1 to 5 in Likert’s scale was used in evaluating the given responses. The degree of positive and negative effects was examined via trend analysis. It was found that stand type had influence on the preferences of visitors regarding the recreational activities. In general, unmanaged and moderately treated stands were more preferred by visitors for the recreational purposes, compared to the previously managed stands. On the other hand, visitors’ preference for the activities were different during two periods (i.e., 1993–2005 and 2006–2018). For each recreational activity, there was an increasing trend from 1993 to 2018. There had been a continuous increase for hunting since 1996, and for trekking and camping after 1999. The increases between 1993–1996 and 1996–1999 were likely due to the increasing awareness of the society as a result of the training and consciousness raising activities for nature conservation. The demand on the recreational activities continuously increased in unmanaged and moderately treated stands, while no significant changes were examined in the previously managed stands. The study points out that forest planning and management should consider different needs of visitors for recreational infrastructure.
Inter population variability of frost-resistance in provenances of scot pines (Pinusylvestris L.R. hamata Steven) in Turkey
(2016-01-01) Özel H.B.; Ayan S.; Isajev V.
Frost-resistance variability of Scotch pine (Pinus sylvestris L. var. hamata Steven) seedlings grown in nurseries conditions, originated from 10 provenances, have been analyzed. The provenances from Black Sea region, Central Anatolian region and Eastern Anatolian region in Turkey have been used in selection of seed zones. The results of frost-resistance tests indicated a strong relationship of implemented freezing degrees with injury degrees of Scotch pine needles and photosynthetic productivities. On the other hand, another significant relationship has been determined between chlorophyll fluorescence and ion leakage methods (r=-0.801). This result shows that those two methods can be safely used in determining the damages due to low temperatures. In frost resistance tests, Scotch pine seedlings from different provenances have been frozen at -10, -20, -30 and -40 °C. According to the Duncan test results, it has been determined that damage increased as temperature decreased. The damage level at -10°C implementation is 3.5% which can be tolerated by plants. But when the temperature has been decreased to -20°C, the level of damage has increased to 51.25%. As a result of photosynthetic analyses in this phase, it has been determined that there is a statistically significant relationship between provenances and temperature levels. Under the light of those findings, they have determined that the photosynthetic productivity has significantly decreased at temperatures between -20°C and -40°C. This situation conforms to injury index values determined in this study. As a result of injury index and photosynthetic productivity tests used for determining the damage after frost-resistance tests, it has been determined that the provenances of Amasya-Kunduz, Bolu-Aladag, Düzce-Yigilca, Samsun-Vezirköprü and Eskisehir-çatacik are more sensitive to frost than other provenances.
Juniperus L. for Restoration of Degraded Forest Lands in Turkey
(2021-01-01) Yücedağ C.; Ayan S.; Farhat P.; Özel H.B.
Degraded forests are among of the most important environmental and commercial problems around the world. Turkey has 22.74 million hectares of forest area, out of which 9.656 million ha (42%) are unproductive. To transform these unproductive forests into productive ones, forest restoration including rehabilitation is one of the best actions. In this sense, juniper species play an important role for degraded lands because they are drought-tolerant and withstand aridity and poor soils better than most timber species grown in Turkey. Therefore, this review presents the ecological considerations for the restoration of degraded forest lands in Turkey under the conditions of climate change. Within this framework, it focuses on the production of planting stock of juniper species, the significance of site-species matching, and post-planting site maintenance for successful rehabilitation.
Phytoremediation and Long-term Metal Uptake Monitoring of Silver, Selenium, Antimony, and Thallium by Black Pine (Pinus nigra Arnold)
(2024-08-01) Şevik H.; Yildiz Y.; Özel H.B.
The Effect of Geographic Location and Seed Storage Time on the Content of Fatty Acids in Stone Pine (Pinus pinea L.) Seeds
(2022-01-01) Özel H.B.; Şevik H.; Onat S.M.; Yiğit N.
The fatty acids content in pine seeds is important because it affects germination success and commercial value. In this study, the amount of fatty acids in the seeds of stone pine (Pinus pinea L.) was determined in seeds collected from different geographical locations and after two-year storage. The pine seeds were collected from different locations where peanut pine is densely located in the Western Black Sea Region of northern Turkey in 2019. The results showed that the content of some fatty acids (C18:1n-9, ƩMUFA, C18:2n-6, and ƩPUFA) in the seeds collected from different geographical locations did not differ significantly, but the content of others (C16:0, C18:0, C20:0, ƩSFA, and C18:3n-3) was dependent on the locations. The difference among locations was up to 40% (p < 0.05). In general, the lowest values were obtained from the seeds of Bartın Karaçaydere, and the highest values were obtained from the seeds of Bartın Çakraz and Bartın Avara locations. After two years of storage, the content of all the fatty acids in the seeds decreased based on the location, and a decrease of more than 25% in the content of some fatty acids was observed.
The effects of rill erosion on unpaved forest road
(2019-01-01) Varol T.; Ertuğrul M.; Özel H.B.; Emir T.; Çetin M.
This research aims to investigate the degree of rill erosion and its relationship with the factors effective on rill volume on unpaved forest roads in Bartın Province in Turkey. For this purpose, measurements were made at 380 sample locations on different regions of the forest roads in Arıt and Hasankadı sub-districts. The measurements were performed on 4 years old unpaved forest roads. Among the road surface (RS), road cut (RC), sidecast fill (SCF) and skid trail (ST) road sections, RS and ST ranked as the first two sections with the highest segment length. Segment length is characterized as the most effective field factor on erosion, which further increased the rill volume by the combined effect of increasing slope, in this research. According to the stepwise (forward-backward) regression analysis results, inclusion of both segment length and slope parameters in the RS, SCF and RC equations supports this finding. The correlation of all road sections (RS, SCF, RC, ST) with the segment length are 0.84, 0.63, 0.75 and 0.83, respectively, and the correlation with the slope are 0.55, 0.73, 0.57 and 0.64, respectively. As a result of the slope-based categorization of the relationship between segment lengths and rill volume for the road sections, R 2 values were found to increase up to 0.88 for RS, 0.78 for SCF, 0,94 for RC and 0.88 for ST. The rill volume at short and steep roads can be lower than the rill volume at long and low-slope roads. Therefore, we calculated the rill volumes per unit road segment area. As a result of application of equations based on shear stress and stream power sediment transport capacity theory, RMSE values with very low mean error were obtained. In further related studies, drainage areas in addition to segment lengths and slope should also be taken into account to determine the positive and negative effects in evaluation of rill erosion amounts. Also, similar studies should be performed on other basins having a larger number of unpaved forest roads as a means to extend the applicability of the obtained findings.
The influence of effective microorganisms on physiological characteristics of containerized taurus cedar (Cedrus libani A. Rich.) seedlings
(2022-01-01) Ayan S.; Çalışkan E.; Özel H.B.; Çelik E.N.Y.; Yılmaz E.; Gülseven O.; Akın Ş.S.
Background: In this study, the impact of Effective Microorganism (EM) applications on some physiological characteristics of 2+0 aged, containerized Taurus cedar (Cedrus libani A.Rich.) seedlings were investigated. EM-1, EM-A, EM-5, and EM-Gold were used as effective microorganism varieties. EM application was repeated twice at two different times. The first application was carried out in April-May 2017 at the beginning of the vegetation period, and the second application was carried out in June-July, when the growth of seedlings was the most active period, according to a randomized plot design with three replications. Results: Physiological measurements on seedlings were carried out at the end of the second vegetation period. According to the results of the study, it was determined that the EM type, dose and application time factors had a significant effect on physiological characteristics such as Chlorophyll a, Chlorophyll b, Total Chlorophyll, Photosynthesis Rate, Transpiration and Relative Humidity. EM-A had a positive effect on photosynthesis rate and EM-5 had a positive effect on all other measured physiological parameters. High dose of EMs had the most positive effect on relative humidity, while medium dose of EMs had the most positive effect on chlorophyll values, transpiration rate and photosynthesis rate. In addition, it was determined that EM application at the beginning of the vegetation period had an increasing effect on all measured physiological parameter values. Conclusion: According to the results of the study, it was concluded that EMs have a positive effect on the physiological quality characteristics of Taurus cedar seedlings and can contribute to the production of seedlings with higher adaptability in afforestation.