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The aim of this study was to determine the best size and shape of containers to produce higher quality seedlings, and determine which treatments (moving the seedlings to other beds, or transfer to bigger containers, or pruning the shoot and root syst em of Ceratonia siliqua seedlings in the nursery) are the best for growth and stabilization in out planting. The study showed that the control seedlings D1 which were growing in traditional plastic containers (1 liter) gave low survival rate which did not exceed 20%, and this was due to numerous reasons mainly roots deformation. Seedlings D8, the containers(2 liters) improved the morphological characteristics of root and shoot system and reduced the roots deformation, which led to higher survival rate reached more than 82%. While the deep containers and the air pruning improved the structure and spread the root system of seedlings D9 and limited the roots deformation, which led to higher survival ratio reached more than 95%. Moving the seedlings to other beds in the nursery improved the survival rate in out planting, which amounted ,in D2, to more than 95% and in D3 over than 67%. Also, the study confirmed that cutting the developing top of shoot system and leaving the seedlings in the beds until their planting date D4 did not give a significant effect compared to D5 in which the developing top of their shoot system was cut and was transferred to bags of (12 liters) with pruning the root system, and the survival rate was more than 72% in D4, and over 62% in D5. Regarding to survival rate under the influence of transport operations to larger bags, the D7 which was transferred to bags of 3 liters capacity surpassed in significant differences and was 77.5% compared to D5 and D6 which was transferred to 12 liters bags, where the survival rate in which was 62.5%.
Estimation of tree and stand volume is a key calculation for productive forest management (de Miguel et al., 2012). A precise estimation of tree volume needs to take the variation in bole forms into account while calculation, this can be done by es timating tree form factor. This study aims to construct a mathematical model to calculate the form factor of brutia pine trees grown in the regions of Rabiaa in northern Latakia. The form factor model can help foresters to precisely estimate the volume of tree and forest stands. During the period 2008-2011, 72 pine trees of various ages and sizes, located in natural stands of different densities and site qualities, were felled. Diameters at different heights of the felled trees were measured; trees volumes and volumes of equivalent cylinders were calculated, and consequently the values of tree form factor were computed. The dataset was randomly split into two parts, 75% (55 trees) of the data for constructing form factor model and 25% (17 trees) for model validation. A form factor model was obtained using the non-linear regression equations in the statistical program SPSS. Value of the coefficient of determination adjusted (R²adj) was about 0.81. The model has been validated using several statistical methods, the relative bias ( e%) was ca. 17.9%, while the value of model accuracy ) % x m ) was 22.9 %. In order to obtain lower value of model relative bias and higher value of accuracy it’s recommended to use a larger database comprising all distribution areas of pine in Syria.
This research aims to test some equations, used in different regions and forest types, for assessing the total height of shoots in the oak )Quercuscalliprinos) Maquis forests, depending on diameter,which enable the estimation of volumes without mea suringthe height of these shoots. This is very important to saveefforts, time and moneyinvested by foresters. The study included102 samples distributed within the most important oak forests on the eastern exposition of the coastal mountains. The plots have rectangular shape with 50 shoots at least. The plots vary in shoot density, soil fertility and Maquiage. In each sample we measured the diameter at a height of 30 cm, the total height of (10-20) shoots of various diameters (low-medium-dominant).
This study aims to construct a mathematical model to calculate the form factor of Palestine Oak Maquis grown on the eastern versants of coastal mountains. The form factor model can help foresters to precisely estimate the volume of tree and forest stands. In the year 2014, 129 oak shoots of various ages and sizes, located in natural stands of different densities and site qualities covering all conditions of region grown on, were felled. Diameters at different heights of the felled shoots were measured; shoots volumes and volumes of equivalent cylinders were calculated, and consequently the values of shoot form factor were computed. The dataset was randomly split into two parts, 70% (90 shoots) of the data for constructing form factor model and 30% (39 trees) for model validation. Several form factor models were developed using the non-linear regression equations in the statistical program SPSS. Best fit to the data was selected and value of the coefficient of determination adjusted (R²adj) was about 0.77. The model has been validated using several statistical methods, the relative bias of the best model ( e%) was ca. -3.6 %, while the value of model accuracy ) % x m ) was 15%. In order to obtain lower value of model relative bias and higher value of accuracy, it’s recommended to use a larger database comprising all distribution areas of oak Maquis in Syria.
This study aimed to estimate the height of the Pinus brutia trees in Kafardabeel forested area- Jableh. Eight mathematical forms (Michailoff, Prodan, Petterson, Parabel, Korsun, Logarithmic, Freese, Chapman-Richards) were used. In 2015, the diamet er of 330 trees at breast height (dbh) were measured, and only heights of 165 of them were taken. Measurements were carried out in 15 sample plots all over the study area to cover site variations in altitude, exhibition, gradient and density. Data were split into two parts: 116 tree (70%) were used for model constrction, while the remaining trees 49 tree (30%) were used for model validation. The Results showed that, Parabel had the highest value for the Coefficient of Determination (R²=0.53) and the lowest value of the relative accuracy (mx%) (17.665%). That means it was the the best model to calculate tree height using diameter at breast height. This model can help foresters in forest management planning for study area and similar sites.
This study was carried out during 2013 – 2015 and aimed to assess the effects of applying dry sewage sludge on dry biomass production and wood volume of Eucalyptus camaldulensis plantation established on sandy soil in Fedio plantation-Lattakia at A pril - 2013. Four experimental treatments were compared at age 22 months: SS1 (sewage sludge 3 kg/tree), SS2 (sewage sludge 6 kg/tree), MF (mineral fertilizer), and C (no fertilizer applications). Aboveground dry biomass production and wood volume in the SS1 treatment were about 107.60 t/ ha and 121.13 m3/harespectively, MF treatment (87.52 t/ha, 96.98 m3/ha) and SS2 treatment (91.12 t/ha, 103.42 m3/ha)and higher than in the control treatment (43.89 t/ha, 51.32 m3/ha ).
Dendrochronology methods are used to study the response of tree rings to environmental factors, where tree rings width are strongly influenced by environmental factors especially climatic ones. In order to study tree rings of brutia pine in Kfarfo forest – Tartus, 12 dominant trees were selected, using increment drill two perpendicular core samples at breast height from each tree were extracted. After treatment, the core samples were cross dated. Tree-rings widths were measured to the nearest 0.01 mm. Consequently, a series of 31 tree rings covering the period 1983-2013 was obtained. Results showed that, tree rings of the years: 1998-1999, 2007-2008 and 2009-2010 were clearly narrow; while rings of the years: 1985-1986, 1991-1992, and 2002-2003 were obviously wide. Whereas, rings of the years: 1986-1987, 1994-1995, 1996 and 1997 were absent. Finally, results reveal that, as precipitation decreased corresponding with temperature increase in the growing season; narrow rings were recorded. While, increasing winter precipitation corresponding with temperature decrease leaded to increase in ring width.
Brutia pine tree grows radially and gives one ring per year, the width of this ring is determined by environmental conditions especially by climatic ones. Dendroclimatology concerns with studying the response of tree rings to climatic conditions. In order to study the radial growth of brutia pine planted 1975 in Heir Brafa, Tartous, Syria.
This research aimed to investigate the competitive situation and the growth reduction as a result of competition for brutia pine trees grown in Kafardabeel stand – Jableh. In the year 2015, 15 circle plots (with area size of 400 m²) in the study a rea planted in 1974 were sampled; all variations in the site like tree density, aspect, slop, topography and site fertility were covered. In the sample plot diameter at breast height of all trees and also coordinates of central tree and coordinates of all compotators as well as were measured. In order to study the competitive situation, two different types of competition indices: position dependent (Heygi1, Heygi2, BAL) and position independent (CCF) indices were used.
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