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This research aimed to evaluate the growth and productivity of planted Pinus pinea in pure stands at "DAHR AL SORANI" forest site. The site is about 50 km north east of Tartous city, which is located in Temperate-Humid Bioclimate Zone. Results sho wed that the stands were not equivalent in growth indicators; this was due to many factors affecting growth like site characteristics and trees density…etc. In spite of the mediocre values of form factor, the volume and mean of annual increment was not influenced. Results revealed that the mean values of tree density was 851 trees/ha and ranged between 350 - 1975 trees/ha, woody volume was averaged at 116.337 m3/ha and ranged between 51.6519 - 215.3635 m3/ha; annual increment had also an average of 4.4548 m3/ha/year and ranged between 1.9866 - 7.9764 m3/ha/year. The study showed a high straightness of pine. Pinus pinea trees had very rarely forked boles.
Palaeomagnetism and some magnetic and physical properties (magnetic susceptibility, intensity of the Natural Remnant Magnetization (NRM), ac current electrical conductivity and density) of 136 samples from 22 sites of the Yemen Volcanic Group TKY (Tertiary and (or) Cretaceous) from igneous rock exposures along the road from Sana’a – west towards Al-Hudyadah were studied. A single population consists of seven Virtual Geomagnetic Poles (VGP), of the Upper Oligocene, was accepted and a mean at 182.81° E, 77.44° N with α95= 12.5° was calculated. The different properties were measured in order to use these properties as characteristic factors to discriminate the neighboring igneous flows. The measurement of the in situ magnetic susceptibility of 140 points, distributed on 7 sub-areas, in the region helped to calculate the mean value of the magnetic susceptibility of each sub-area, which might be used in any magnetic interpretation of aeromagnetic or magnetic anomalies. Also, the density of 132 samples were measured and a mean value of the density of each sub-area was calculated in order to be used in any future interpretation of any gravity anomaly in the area.
شملت هذه الدراسة حصر و تعريف 80 نوعاً و تحت نوع واحد من الأعشاب تنتمي لـ 64 جنساً موزعة على 28 فصيلة ضمن ثلاثة بساتين للحمضيات في منطقة اللاذقية على مدار أربعة فصول خلال الفترة الواقعة من أيلول 2014 حتى آب 2015. تم حساب كل من الكثافة و الكثافة النسبي ة و التردد و التردد النسبي لكل نوع عشبي لمعرفة تركيب الغطاء العشبي و أهمية الأنواع المنتشرة. كانت نسبة الأنواع التابعة لأحاديات الفلقة 24.69%، أما التابعة لثنائيات الفلقة كانت نسبتها 75.31%، و شكلت الأنواع الحولية نسبة كبيرة بلغت 85.19% و المعمرة 13.58% و ثنائية الحول 1.23%. دلت النتائج أن أكثر أنواع الأعشاب الموجودة في بساتين الحمضيات تتبع الفصيلة الكلئية (Poaceae)، حيث تضمنت 17 نوعاً و تحت نوع واحد، و تلتها الفصيلة الفولية (Fabaceae (9 أنواع و الفصيلة النجمية (Asteraceae (8 أنواع و الفصيلة الحليبية (Euphorbiaceae (7 أنواع. وكان أكثر أنواع أحادية الفلقة كثافةً نوع السعد Cyperus rotundus L. بكثافة بلغت 20.2 نبات/م2 خلال فصل الصيف، أما أكثر أعشاب ثنائيات الفلقة كثافةً عشبة حشيشة الزئبق Mercurialis annua L. بكثافة59.27 نبات/م2 خلال فصل الخريف. و من أهم نتائج الدراسة أيضا إضافة 3 أنواع، و تحت نوع واحد من الفصيلة الكلئية (Poaceae) للفلورا السورية.
Palaeomagnetism and some magnetic and physical properties such as magnetic susceptibility, intensity of remanent magnetisation, ac current electrical conductivity and density for the number order (٣٩ - ٥٤) of samples from ٩ sites of Upper Pliocene basaltic rocks from the area west of Homs were studied. The aim of the works to extend the previous studies (Abou- Deeb, ١٩٩٧a, b) to other regions so that these properties might be used as characteristic factors in discriminating the basaltic flows.
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