نتایج جستجو برای: fraxinus excelsior

تعداد نتایج: 1212  

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه گیلان - دانشکده منابع طبیعی صومعه سرا 1389

پروانه سفید آمریکایی یکی از مهمترین آفات جنگل، باغ ها و مزارع در دنیا محسوب می گردد.. در این بررسی، بیولوژی و ترجیح میزبانی پروانه سفید آمریکایی روی چهار گونه morus nigra، fraxinus excelsior، populus deltoiedes و taxodium distichum مورد مطالعه قرار گرفت. از مهمترین صفات دیگری که در این بررسی اندازه گیری شد شاخص های تغذیه از جمله نرخ مصرف نسبی، نرخ رشد نسبی، کارایی تبدیل غذای خورده شده ،کارایی ت...

ژورنال: :مجله پژوهشهای گیاهی 2015
جواد جعفری مسعود طبری کوچکسرایی سید محسن حسینی یحیی کوچ

به­منظور بررسی تأثیر فاکتور­های خاک روی تنوع زیستی گیاهی و گروه­های اکولوژیک گیاهی، 220 هکتار از جنگل­های جوزک-درکش خراسان شمالی مورد بررسی قرار گرفت. ابتدا 55 قطعه نمونه 20 ×20 متر برای برآورد پوشش گیاهی انتخاب شد. سپس 18 نمونه از لایه معدنی خاک (عمق­های 10-0 ،20-10 و 30-20 سانتی­متر) برداشت شد و اسیدیته، هدایت الکتریکی، ماده آلی، نیتروژن کل، فسفر قابل جذب، بافت خاک، پتاسیم و نسبت کربن به نیتر...

2015
Vasthi Alonso Chavez Stephen Parnell Jan Stenlid Jonas Oliva Audrius Menkis

Ash dieback is a fungal disease (causal agent Hymenoscyphus fraxineus) infecting Common ash (Fraxinus excelsior) throughout temperate Europe. The disease was first discovered in the UK in 2012 in a nursery in Southern England, in plants which had been imported from the Netherlands. After sampling other recently planted sites across England, more infected trees were found. Tree trade from outsid...

Journal: :Tree physiology 2006
Têtè S Barigah Tharwat Ibrahim Aurore Bogard Benjamin Faivre-Vuillin Louis André Lagneau Pierre Montpied Erwin Dreyer

We assessed the irradiance-related plasticity of hydraulic architecture in saplings of Betula pendula Roth., a pioneer species; Acer pseudoplatanus L., Fraxinus excelsior L. and Quercus robur L., which are post-pioneer light-requiring species; and Quercus petraea Matt. Liebl. and Fagus sylvatica L. Plants were grown in pots in 36%, 16% and 4% of full sunlight. Hydraulic conductance was measured...

Journal: :Journal of experimental botany 2012
Estelle Arbellay Patrick Fonti Markus Stoffel

Cambial injury has been reported to alter wood structure in broad-leaved trees. However, the duration and extension of associated anatomical changes have rarely been analysed thoroughly. A total of 18 young European ash (Fraxinus excelsior L.) trees injured on the stem by a spring flood were sampled with the aim of comparing earlywood vessels and rays formed prior to and after the scarring even...

2016
Eric Goberville Nina-Coralie Hautekèete Richard R. Kirby Yves Piquot Christophe Luczak Grégory Beaugrand

Beyond the direct influence of climate change on species distribution and phenology, indirect effects may also arise from perturbations in species interactions. Infectious diseases are strong biotic forces that can precipitate population declines and lead to biodiversity loss. It has been shown in forest ecosystems worldwide that at least 10% of trees are vulnerable to extinction and pathogens ...

Journal: :The New phytologist 2005
Filippo Bussotti Giovanni Agati Rosanna Desotgiu Paolo Matteini Corrado Tani

This paper compares the responses to ozone in five woody species: Fagus sylvatica (FS), Acer pseudoplatanus (AP), Fraxinus excelsior (FE), Viburnum lantana (VL) and Ailanthus altissima (AA). The hypothesis being tested was that the strategies that plants adopt to resist oxidative pressure are species-specific. The study was carried out on field grown plants in an area in Northern Italy characte...

Journal: :Tree physiology 2016
Shan Li Marion Feifel Zohreh Karimi Bernhard Schuldt Brendan Choat Steven Jansen

Establishing physiological thresholds to drought-induced mortality in a range of plant species is crucial in understanding how plants respond to severe drought. Here, five common European tree species were selected (Acer campestre L., Acer pseudoplatanus L., Carpinus betulus L., Corylus avellana L. and Fraxinus excelsior L.) to study their hydraulic thresholds to mortality. Photosynthetic param...

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