Cedrus Libani Research Articles

Surprisingly wide climatic niche breadth of a relict mountain species raises hope for survival under climate change

AbstractAimsWe assessed the juvenile climatic niche breadth of a relict mountain species by comparing field observations and transplant experiments within and beyond the elevational limits of its distribution range.LocationLebanon – Near East – Mediterranean region.MethodsWe studied the survival and growth of the Cedar of Lebanon (Cedrus libani) to determine the lower and upper elevational range limits of its juvenile stage through an experimental setup with and without water supplementation and with potentially competing species as a control. The experiment included eight common gardens at elevations ranging from 110 to 2330 m, within and far beyond the warm and cold limits of Cedar distribution observed under natural conditions.ResultsWe observed unexpectedly high survival and growth rates of Cedar at elevations well below the range of its natural distribution in Lebanon. Below the observed warm limit, water stress at very low elevations and competition at low and medium elevations limited juvenile survival. In contrast, cold temperature and water stress limited survival at elevations slightly above the observed upper natural limit. The experimental setup demonstrated that the elevation range suitable for Cedar growth and survival was twice as wide as the range within which Cedar is observed under natural conditions.Main ConclusionsHigh survival rates experimentally observed beyond the warm limit of the natural distribution range of the Cedar of Lebanon raise hope for its resilience to ongoing climate warming. If this pattern were frequent among montane species, it would challenge predictions of massive extinction with climate change and pave the way for promoting adaptive actions such as competition management to improve their survival.

Lebanese Cedar, Skeuomorphs, Coffins, and Status in Ancient Egypt

In ancient Egypt, as with many cultures, funerary objects often communicated aspects of access, power, and social status. Lebanese cedar, for instance, was selected as a particularly desirable material from which to craft the coffins of Egypt’s upper echelons. This imported timber was both structurally superior to local woods and had important social and religious significance. For the slightly lower-ranking elite of Egypt, for whom cedar was inaccessible, local wood skeuomorphs that imitated cedar coffins were created in their place. The skeuomorphs enabled these individuals to demonstrate their knowledge of elite styles and tastes, and, due to the power of the image in ancient Egypt, also allowed for them to borrow the religious power of cedar wood to protect and enhance their own coffins. In this paper, a selection of Old to Middle Kingdom coffins are discussed to demonstrate the ways that cedar was emphasized as a construction material by the upper elite and mimicked by the middle and lower elite. This helps to demonstrate both the value of cedar in ancient Egypt, as well as the means by which imagery could be manipulated to gain access to the power of this potent material.

Infestation Rates, Seasonal Abundance of Aphids and Relationships with Some Environmental Factors in Different Forest Habitats in Southwestern Türkiye

Aim of study: It was to determine the infestation rate and seasonal abundance of aphids and their relationships with some environmental factors in forests. Area of study: The study was conducted in Pinus nigra, P. brutia, Cedrus libani, Abies cilicica, Juniperus spp., Quercus spp. and Robinia pseudoacacia forests (34 sampling areas) in Isparta. Materials and methods: Systematic sampling was carried out monthly throughout April-October in 2019-2020. As aphid density and infestation rates were determined, 30 cm shoots were taken from 10 trees. The slope, aspect, elevation, forest characteristics, daily minimum, average, and maximum temperature and total precipitation were recorded. Main results: Abundance were highest in P. nigra, Quercus and Robinia pseudoacacia forests in both years. There was a significant correlation between abundance and development stages (p

A new species of Acantholyda (Hymenoptera: Pamphiliidae) from Lebanon, associated with Cedrus libani (Pinaceae)

Acantholyda nemeri sp. nov. (Hymenoptera: Pamphiliidae) is described from adults of both sexes from Lebanon. Its host plant is probably Cedrus libani, the cedar of Lebanon (Pinaceae). The new species shows a combination of adult characters that makes placing it in one of the two widely-recognised subgenera of Acantholyda problematic. Acantholyda nemeri is only the fourth sawfly species associated with Cedrus as a larval host and, together with Cephalcia tannourinensis Chevin, 2002 (Pamphiliidae), the second from C. libani. A key to adults of Acantholyda Costa, 1894 species of the Western Palaearctic is provided.

Use of Spinning Rollers for Surface Densification of Wood

In this study, softwood cedar of Lebanon (Cedrus libani A.Rich.) and hardwood black poplar (Populus nigra L.), turned into cylinders by turning, were subjected to a surface densification process. Densification was carried out on the lathe using the spinning roller designed and manufactured for this purpose. Hardness, brightness and roughness (Rz) measurements were carried out on undensified and densified regions of the cylindrical solid wood materials. An increase in hardness and brightness and a decrease in roughness values occurred under all densification conditions. The highest surface hardness values occurred in cedar of Lebanon at 0.081 mm/rev feed, 200 rpm spindle speed, and 1 mm densification depth. On densified wood surfaces, as the feed from the densification parameters increases, the hardness decreases, and as the densification depth increases, the hardness increases-. The effect of surface densification parameters on the gloss and roughness results of the samples shows no linear effect in terms of experimental parameters. In both species, lower spring back was obtained at low depth of densification.

Impact of three distinct mycorrhizal species on Cedrus libani seedling development and nutrient uptake

Aim of study: In semi-arid afforestation sites, the study aimed to create mycorrhizal seedlings with high vitality, health, and tolerance to harsh environments. The study's hypotheses state that mycorrhizal inoculation will improve Cedrus libani (Taurus cedar) seedlings' growth characteristics, nutrition, root colonization, and mycorrhizal reliance. Area of study: The Eastern Mediterranean Research Institute laboratory and greenhouse in Tarsus district-Mersin, Türkiye. Material and methods: The experiment involved inoculation of three ectomycorrhizal fungal species (Lactarius delicious, Hebeloma crustuliniforme, Tricholoma ustale) collected from natural cedar stands on to cedar seedlings grown in two different substrates (sterilized, non-sterilized. Inoculation was carried out by dipping the roots of Cedrus libani A. Rich (Taurus cedar) seedlings into mycorrhizal mycelia. Main results: Cedar seedlings infected with mycorrhiza exhibited a greater biomass ratio in comparison to the control seedlings. Substrate sterilization increased seedling growth variables. The highest growth, some nutrients such as N, P, K, Fe and Zn uptake, root colonization and mycorrhizal dependence occurred in seedlings with H. crustuliniforme and L. delicious. Research highlights: Although this study is limited to Taurus cedar-mycorrhiza combinations, it may also be applicable to different mycorrhizal fungal species and many other valuable host tree species. More research is needed on the adaptation of different mycorrhizal species to habitats to increase the success of afforestation efforts in arid and semi-arid regions.

The Therapeutic Potential of Essential Oils in Managing Inflammatory Skin Conditions: A Scoping Review.

Conventional therapy is commonly used for the treatment of inflammatory skin conditions, but undesirable effects, such as erythema, dryness, skin thinning, and resistance to treatment, may cause poor patient compliance. Therefore, patients may seek complementary treatment with herbal plant products including essential oils (EOs). This scoping review aims to generate a broad overview of the EOs used to treat inflammatory skin conditions, namely, acne vulgaris, dermatitis and eczema, psoriasis, and rosacea, in a clinical setting. The quality, efficacy, and safety of various EOs, as well as the way in which they are prepared, are reviewed, and the potential, as well as the limitations, of EOs for the treatment of inflammatory skin conditions are discussed. Twenty-nine eligible studies (case studies, uncontrolled clinical studies, and randomized clinical studies) on the applications of EOs for inflammatory skin conditions were retrieved from scientific electronic databases (PubMed, Embase, Scopus, and the Cochrane Library). As an initial result, tea tree (Melaleuca alternifolia) oil emerged as the most studied EO. The clinical studies with tea tree oil gel for acne treatment showed an efficacy with fewer adverse reactions compared to conventional treatments. The uncontrolled studies indicated the potential efficacy of ajwain (Trachyspermum ammi) oil, eucalyptus (Eucalyptus globulus) oil, and cedarwood (Cedrus libani) oil in the treatment of acne, but further research is required to reach conclusive evidence. The placebo-controlled studies revealed the positive effects of kānuka (Kunzea ericoides) oil and frankincense (Boswellia spp.) oil in the treatment of psoriasis and eczema. The quality verification of the EO products was inconsistent, with some studies lacking analyses and transparency. The quality limitations of some studies included a small sample size, a short duration, and the absence of a control group. This present review underscores the need for extended, well-designed clinical studies to further assess the efficacy and safety of EOs for treating inflammatory skin conditions with products of assured quality and to further elucidate the mechanisms of action involved.

Gene Diversity In Seed Crop Of Taurus Cedar (Cedrus Libani A. Rich.) Over An Altitudinal Range

There could be many environmental and biological impacts such as edaphic, geographic, climatic, age, tree structure and population on morphological, physiological and genetically seed quality in plant species. Gene diversity is an important mirror of genetically seed quality. Gene diversity in seed crops were estimated based on female and male strobili productions of fifty trees (N) randomly chosen from each population sampled over an altitudinal range as low (1200-400 meters ≤ altitude), middle (1400 m < altitude ≤ 1600 m), high (1600 m < altitude ≤ 1800 m), and very high (1800 m < altitude) in Taurus cedar also known as cedar of Lebanon (Cedrus libani A. Rich.) for two consecutive years (2021&2022). The variation in strobilus production was subjected to estimation of female and male fertility variation. The total fertility variation (Ψ) was estimated from the female and male fertility variation. Impacts of some growth characteristics (tree height and diameter at breast height) on strobili productions were also investigated. Strobili productions varied among the populations and individuals within population, and between years. The differences for populations and years were also found for coefficient of variations which were mirror of fertility variation of the strobili productions. Tree height and diameter at breast height seemed more reasonable predictor than age for number of strobili. Fertility variations of female parents were generally higher than that of male in both years. First year showed generally higher parental variations in individual populations. Gene diversity (GD=1-0.5Ψ/N) ranged from 0.967 to 0.974 for the populations and years. The loss of highest gene diversity was 0.004 in low population (0.967 & 0.971) between years. Results of the study indicated that altitudinal gene diversity of seed crop could be used to produce genetically quality seed and their grading. Moreover, data sets can be used to fill the Forest Landscape Restoration library (FLR-Library).

Life Cycle and Characterization of Cedar Moth Insect (Dichelia cedricola) on Lebanese Cedar Trees (Cedrus libani) at The Cedar and Fir Reserve, Slenfeh, Syria

Hasan, R., M. Ali, A. Ramadan and O. Merhej. 2024. Life Cycle and Characterization of Cedar Moth Insect (Dichelia cedricola) on Lebanese Cedar Trees (Cedrus libani) at The Cedar and Fir Reserve, Slenfeh, Syria. Arab Journal of Plant Protection, 42(3): 263-268. https://doi.org/10.22268/AJPP-001243 This study was carried out in the Cedar and Fir Reserve, Slenfeh, Syria during the period 2021-2022, where the Lebanese cedar moth, Dichelia cedricola (Lepidoptera: Tortricidae) was observed for the first time in Syria on the Lebanese cedar tree (Cedrus libani A. Rich.). Infestation symptoms were described and the most important biometric measurements of the different stages of the insect were recorded. The average body length of the fourth and fifth larval instars was 12.5±2.6 mm, the average length of the pupa was 9.7±1.2 mm. The average length of the female adult was 11.1±1.3 mm, and the wingspan was 18.7±2.6 mm. The average length of the male adult was 9.4±1.5 mm, and the wingspan was 15.7±2.6 mm. The life cycle of the insect was also investigated in the field, where the insect (in its different stages) was active from April to November. Caterpillars fed on needles and new buds and used needles for nesting and overwintering, which causes the leaves to fall and consequently cause damage to the tree. Control measures need to be investigated. Keywords: Cedar moth, Dichelia cedricola, Lebanese cedar. Cedrus libani, Life cycle

Limited influence of air temperature and precipitation on six-year survival and growth of non-native tree species in a Central European multi-site field trial

The biggest challenge for forest management in the near future will be the silvicultural adaptation of forests on sites where climate change will increase the risk for drought induced tree mortality and for a decrease of the growth performance. One management option is the diversification by promoting climate change adapted non-native tree species. Currently, we have in depth experience with only a few non-native tree species in Central Europe. Other tree species that may complement the species pool in Central Europe need to be carefully selected by a range of criteria. Before establishing larger silvicultural experiments at stand-level, the suitability of species to grow well with a low risk of failure under expected future climatic conditions as well as a good performance already today should be tested, amongst other aspects. We present results of a multi-site common garden experiment where growth and survival of five non-native tree species (Abies bornmuelleriana, Cedrus libani, Fagus orientalis, Tilia tomentosa, and Tsuga heterophylla) and one climate adapted local native species per site are tested in five field trials in Austria, Germany and Switzerland along a temperature (7.9–10.4 °C mean annual Temperature) and precipitation (490–1147 mm annual precipitation) gradient. Each species was replicated on three plots per site using a block-wise design. Lower survival and growth of the non-native species as the native reference on most sites indicate that the studied non-native species are today not as well adapted to current climatic conditions as native species. However, the performance of the non-native species was sufficiently high to justify further trials. Survival and growth rates were mostly equally high on the two sites at the opposing ends of the temperature and humidity gradient and lower on all other sites. Height growth and survival were only marginally affected by the strong summer drought in 2018 in all except one site, presumably due to the low water storage capacity of the sandy soils on this site. This indicates that the tested non-native tree species grow well in the wide range of climatically changing weather conditions from our transnational study sites across Central Europe. So far, the tested tree species did not reach their climatic growth limitation. However, edaphic site conditions may have influenced the performance of the tested non-native species as well and must be considered when discussing the suitability of these tree species.

THE VEGETATION HISTORY OF THE SHEPHELAH, SOUTHERN LEVANT: MIDDLE BRONZE AGE–HELLENISTIC PERIOD (c.2000–100 BC)

SummaryAlthough the Shephelah region (Israel) is of a great archaeological significance and has been intensively excavated, very little is known about its landscape history. This study presents two large‐scale charred wood assemblages (>2300 items) that were recovered from Tel Azekah and Tel Lachish in order to reconstruct the ancient vegetation of the Shephelah. The two assemblages cover a temporal range from the Middle Bronze Age through the Hellenistic period (c.2000–100 BC). This new diachronic environmental investigation demonstrates that the natural arboreal vegetation in the Shephelah was dominated by oak and pistachio. From the perspective of the regional fruit tree horticulture, olive was the dominant component, indicating that the region included extensive olive orchards. Other documented fruit trees are grapevine, fig, sycamore fig, carob, date palm and almond. The high frequencies of olive remains throughout all investigated periods point to climatic conditions in the region being close to what we are facing today, with at least 400–450 mm of annual precipitation, which is required for a profitable grove. During the Iron Age II, the proportion of olive remains reached its zenith, most probably as a result of Assyrian agroeconomic management that assigned the Shephelah to olive oil production. At the same time, a reduction in natural Mediterranean trees was identified, representing intense human pressure on the natural environment. The discovery of charred cedar of Lebanon remains only at Lachish points to the high status of the site within the region.

Reclamation of abandoned magnesite site using amendments and plantation

This study aimed to determine the suitable reclamation ways of post‐mining magnesite. It was hypothesized that adding amendments and planting would decrease pH, increasing the nutrient availability and enhancing the soil microbial activity. Treatments included 200 g gypsum, 2 kg goat manure, and 200 g sulfur per square meter. Cedar (Cedrus libani A. Rich.), black locust (Robinia pseudoacacia L.), black pine (Pinus nigra J.F. Arnold), and sainfoin (Onobrychis sativa L.) were planted. Before and after the treatments, samples were taken from each experimental unit and analyzed. Analysis of the data indicated that the pH had decreased by 0.6 and 0.5 units on the gypsum + sulfur‐ and gypsum + manure‐treated experimental units, respectively, compared to the other treated plots. In addition, using manure significantly increased the organic matter N, P, and K content, by 3‐fold, 2.5‐fold, 7.5‐fold, and 2.5‐fold, respectively, and enhanced microorganism activity. The sulfur + manure treatment increased microbial C and N approximately twofold. Because the manure, sulfur, and gypsum treatments improved the tailings conditions for plant growth, the use of these amendments for mine tailing reclamation was strongly recommended. Across all treatments, cedar and black pine demonstrated 83 and 77% survival rates for the first 3 years of afforestation, respectively. For the same period, the black locust survival rate was 35% lower than that of the other species. The gypsum + manure application increased seedling height growth by about 20% for all three species compared to the other treatments.

Exploring the Larvicidal and Repellent Potential of Taurus Cedar (Cedrus libani) Tar against the Brown Dog Tick (Rhipicephalus sanguineus sensu lato).

This study investigated the potential acaricidal and repellent effects of tar obtained from the Lebanon cedar (Cedrus libani A. Rich.) against the brown dog tick species Rhipicephalus sanguineus sensu lato Latreille (Acari: Ixodidae). The goal was to find an alternative, safe, and effective way to eliminate ticks. Tar is traditionally extracted from cedar trees in the Antalya region of Türkiye. The composition of the tar is primarily characterized by a diverse mixture of terpenes, with β-himachalene (29.16%), α-atlantone (28.7%), ar-turmerone (8.82%), longifolene-(V4) (6.66%), α-himachalene (5.28%), and β-turmerone (5.12%) emerging as the predominant constituents. The toxic effects of tar on tick larvae were studied through larval immersion tests (LIT), and its repellent activity was evaluated using a new larval repellent activity test (LRAT). The results revealed significant acaricidal effects, with mortality rates of 77.7% and 82.2% for the Konyaalti and Kepez strains of the brown dog tick, respectively, in response to a 1% concentration of tar. LC50 and LC90 values were determined as 0.47% and 1.52% for the Kepez strain and 0.58% and 1.63% for the Konyaalti strain, respectively. When comparing the repellent effect of tar to the widely used synthetic repellent DEET, repellency rates of up to 100% were observed. As a result, this study establishes, for the first time, the larvicidal and repellent effects of C. libani tar on ticks.

Evaluation of biological activity of tar extracted from Pinus brutia and Cedrus libani from Turkey

Evaluation of biological activity of tar extracted from Pinus brutia and Cedrus libani from Turkey

Use of Spinning Roller in Cylindrical Densification; Spring back in Black Poplar, Larch and Cedar of Lebanon after Densification

Wood materials have been the solution to many needs throughout history due to their unique positive properties. By improving the properties of wood materials, their areas of use can be expanded and ensured that they are preferred. The densification process is one of the studies carried out to improve wood material properties. With densification, the physical and mechanical properties of the wood material are improved. There are many different methods used for densifying wood materials. While the densification process brings many positive properties to the wood material, an undesirable situation such as spring-back after the process is the negative side of the densification process. In this study, black poplar (Populus nigra L.), larch (Pinus nigra Arnold) and cedar of Lebanon (Cedrus libani A.Rich.) trees were shaped into cylinders on a lathe. After that, densification processes were carried out on the lathe machine using the spinning roller designed and manufactured for this purpose. Densification processes were carried out at 0.081, 0.121, and 0.202 mm/rev feed, at 200 and 400 rev/min, and 0.5 and 1 mm densification depths. The spring-back rates after densification in three different types of cylindrical wood materials were investigated. Theoretical and experimental spring-back amounts of test specimens whose surfaces were densified under different densification conditions were interpreted. When evaluated in general, the highest densification rate was obtained in black poplar wood species, 0.081 mm/rotate feed, 200 rpm spindle speed and 1 mm depth of densification. The lowest spring-back ratio was obtained in larch tree species, 0.121 mm/rotate feed, 400 rpm spindle speed and 1 mm depth of densification. The highest densification percentage was obtained in black poplar tree species, and the lowest in larch tree species. The lowest percentage of spring-back was obtained in the larch tree species and the highest in the black poplar tree species.

Nutrient pools and loss due to the removal of harvesting residue in cedar plantations (a case study from Türkiye).

Determining the nutrient stocks and revealing the extent to which these stocks will be affected by the interventions in forest ecosystems are crucial for sustainable forest management. This study aimed to determine the nutrient stock of cedar (Cedrus libani A. Rich.) plantations at different stands with various diameter classes and estimate the nutrient stock to be removed from the forest due to harvesting. Soil and plant samples were collected from 40 plots in Eskişehir and Afyonkarahisar provinces in Turkey. The variation in the nutrient concentrations and stocks of different components of the ecosystem were evaluated by analysis of variance and the decrease via harvesting by regression analysis. The results showed that the concentrations of N, P, K, Mg, S, Fe, Zn, and Mn were highest in the needles, Ca in the bark, Cu in the needles, dead branches, and root. In the large-diameter forest (LDF), dbh=20.0-35.9 cm, the highest P stock was found in the trees, Fe stock in the forest floor, and S stock in the soil and trees. As a result, the forest floor should be protected as it is the crucial component of both the nutrient cycle and the Fe stock in the ecosystem. In LDF, 28.4-37.3% of the nutrient stored in the trees would be removed from the ecosystem in the case of moderate thinning with whole-tree harvesting, while only 5.9-14.1% of the nutrient stock in the case of stem-only harvesting. For these reasons, leaving logging residues after harvesting in the forest would minimize nutrient loss. The study results showed that improved nutrient management in a forest ecosystem will make a significant contribution to the sustainability of forests.

Differences in virulence of genets of Heterobasidion annosum and susceptibility of young plants of different conifer species and origins

AbstractHeterobasidion species are the most important pathogens causing root and stem rot on conifers in northern hemisphere forests. The host list of this complex is very wide and includes over 200 species of trees and shrubs. Among the members of this complex, Heterobasidion annosum s. s. has the largest host range. In this study, young plants of Pinus sylvestris, Picea orientalis, Abies nordmanniana, Cedrus libani and Pinus brutia (three different origins) were inoculated on the lower stem with known genets of Heterobasidion annosum s.s. collected from Pinus brutia stands in south‐western Türkiye. Infection frequency, assessed as presence of the conidial stage in stem discs following incubation, in the inoculated seedlings was 100%. The Heterobasidion annosum s. s. isolates were re‐isolated from all inoculated host species. Control seedlings showed no symptoms of disease. Mortality in inoculated plants was 11.5% of the 735 inoculated plants, which died over an 8‐weeks incubation period. The isolates showed greater growth on Cedrus libani, Pinus sylvestris and Picea orientalis seedlings compared to other species tested. On the other hand, it was found that the least affected seedlings were Pinus brutia TB12 and Abies nordmanniana. This study proved that differences occur in aggressiveness of Heterobasidion annosum s. s. to host species. A striking point in the results is that, despite being the host species from which the isolates were obtained, Pinus brutia seedlings showed lower sensitivity to Heterobasidion annosum s. s. than the other conifer species tested. Inoculations of three different Pinus brutia provenances suggested there was no significant difference in mean lesion lengths and fungal growth values in Pinus brutia plants, except in Pinus brutia TB14, which was more susceptible to extension growth of the pathogen.

Effect of silane-siloxane based water-repellent impregnant on the dimensional stability of some wood species

A silane-siloxane based water-repellent substance (S-WR) was used as an impregnation material for Scots pine (Pinus sylvestris L.), black pine (Pinus nigra Arnold), sessile oak (Quercus petraea Liebl.), and cedar (Cedrus libani A. Rich). In the impregnation process, the immersion method was carried out for various periods (30 min, 3 h, and 24 h). Following impregnation, physical properties of the wood (retention, contraction, expansion, water intake rate, specific gravity, etc.) were determined. The retention was highest in sessile oak wood (0.96%) and lowest in black pine wood (0.24%). The highest specific gravity value was found in stemless oak (0.86 g/cm³) impregnated for 24 h, and the lowest air-dry specific gravity value was found in Scots pine (0.40 g/cm³) impregnated for 30 minutes Absolutely dry (0% humidity) specific gravity was highest in sessile oak for 24 h (0.83 g/cm³). Shrinkage was highest in the sessile oak control sample (13.5%). The expansion amount was highest in the cedar wood control sample (17.5%) and lowest in sessile oak wood (1.66%). The highest water uptake rate (SAO) was determined in Scots pine wood at 96 h (105%), and the lowest in sessile oak wood in 24 h (8.80%). In summary, silane-siloxane based water-repellent impregnation material was found to be effective in providing dimensional stability in wood.

Characterization and encapsulation efficiency of zein nanoparticles loaded with chestnut fruit shell, cedar and sweetgum bark extracts

Zein nanoparticles (ZNPs) loaded with bioactive extracts of chestnut (Castanea sativa Mill.) shell, cedar (Cedrus libani) and sweetgum (Liquidambar orientalis) bark wastes were produced using different methods. Nanoprecipitation, high-speed homogenization and ultrasonic homogenization allowed the fabrication of ZNPs with particle sizes smaller than 202.40 nm, 430.25 nm and 325.50 nm, respectively. The smallest nanoparticle size was achieved at 132.81 nm for sweetgum bark extract-loaded ZNPs obtained by the nanoprecipitation method. Encapsulation efficiency (EE) was between 34.03 and 96.83% for all zein nanoparticles fabricated under different mixtures and process conditions. Zein concentration and extract ratio played an essential role in the EE of nanoparticles. The best conditions were determined to obtain the desired properties of ZNPs based on particle size, polydispersity index and EE by using a central composite rotatable design. The nanoprecipitation method was more appropriate for producing chestnut and cedar shell/bark extract-loaded nanoparticles. In contrast, the high-speed homogenization method was suitable for producing sweetgum bark extract-loaded nanoparticles. As a result of the encapsulation of various shell/bark extracts within zein nanoparticles, value-added products were generated from wastes having bioactive compounds. The developed zein nanoparticles for each extract type would offer eco-friendly, simple and safe food processing and packaging systems.

Growth rate and economic evaluation of mixed stands established with Cedrus libani and Pinus nigra

ABSTRACT This study aimed to (1) investigate the long-term results of Cedrus libani + Pinus nigra mixed afforestation and (2) compare it with pure P. nigra afforestation in terms of wood production, economic return, and carbon (C) sequestration. The study was conducted in Elazığ-Sivrice, southeastern Turkey. Data were collected from six sample plots, and stem analysis for each species in the mixed stand was performed to reveal the growth and development of the basal-area-averaged trees. Statistical analyses showed that the pure P. nigra stands were superior to the mixed stands in terms of wood production (236 m3 ha−1 vs. 150 m3 ha−1), wood economic value ($19,551 ha−1 vs. $11,483 ha−1), and C sequestration (93 t ha−1 vs. 64 t C ha−1) at 54 years old. The lower values calculated for the mixed stand may have been due to the incompatible growth curves of the two species. These results imply that if the aim is to obtain wood products, pure P. nigra stands may be more advantageous than mixtures of C. libani and P. nigra for afforestation.