نتایج جستجو برای: the species diversity

تعداد نتایج: 16168662  

Dorna Rezaei Maziar Haidari

Silvicultural operation need to notice the species diversity. To this study Gomarlang district in marivan region, northern zagros forest was selected. In this study 30 circle sample plots (500 m2) were collected by random method. In every sample plot the kind of species and number of trees and shrub were recorded. In the sample plots the micro plots of 5 m by 5 m (i.e. area of 25 m2) were desig...

Journal: :بوم شناسی کشاورزی 0
الهام عزیزی لیلا علیمرادی رضا قربانی

in order to evaluate the weed diversity in forage crop fields such as alfalfa (medicago sativa l.), clover (trifolium sp.) and sainfoin (onobrychis spp.) in different provinces of iran, a study was conducted by using data from reports of plant protection organization, ministry of agriculture during 2008. after evaluation of weed species and definition of weed family, these species classified ba...

ارزانی, حسین, برهانی, مسعود, بصیری, مهدی, زارع چاهوکی, محمدعلی, فرح‌پور, مهدی,

In order to investigate the effects of range management plans on species diversity, richness and evenness in Semirum rangelands, 52 sites (28 with treated plan and 24 without treated plan) were selected. The non-parametric indices for species richness (Margalof, Menhinick, Jacknife and counting method) and species diversity (Simpson, Camargo, Smith and Wilson and modified Nee) were compared in ...

Journal: :international journal of advanced biological and biomedical research 2013
abas jamshidi bakhtar khosro sagheb-talebi mohamad reza marvi mohajer maziar haidari

fire, as a natural ecological disturbance factor in forest, this study located in the marivan region, northern zagros forest, and western iranian state of kurdistan. in each burned and unburned area 30 circle sample plot (1000 m2) were collected by randomized–systematic method in the 100×200 m net (in total 60 plots). in every sample plot the kind of species, number of tree, the height of coppi...

خلیل‌آبادی, سمیه, سفیانیان, علیرضا, متین‌خواه, سیدحمید, همامی, محمودرضا, کابلی, محمد,

  Determining landscape parameters influencing species richness of habitat patches is one of the most important issues in conservation biology. Many previous studies have investigated the influence of habitat parameters on bird assemblages in forest patches, but studies seeking effects of oasis parameters on bird assemblages are very scarce. Karkas Protected Area is located in semi-arid zone in...

Journal: :journal of rangeland science 2010
f. fahimipoor m. a. zare chahouki m. jafari m. goldansaz z. mohhebi

plant diversity conservation is a main objective in rangelandmanagement. plant diversity is a suitable index for showing the changes ofvegetation in rangelands and has a high correlation with ecosystem parameters.therefore, using this index it is possible to find the changes and manage theecosystem correctly. the current research was performed to determine the speciesdiversity in fashandak rang...

Adel Sepehry Hossein Barani Mohsen Sharafatmandrad,

In arid and semi-arid rangelands, grazing as one of the natural or human induced processes has direct and indirect effects on structure and dynamics of plant community and ecosystems. A study was done to analyze the effects of grazing on plant species diversity and Plant Functional Types‘ (PFTs) diversity of arid and semi-arid rangelands. We analyzed plant richness and diversity data from 75 sa...

This article presents an analysis of plant species richness and diversity, concerning some climatic variables along a 1500-m elevation gradient on the Binalood Mountain in Heydari Wildlife Refuge (HWR), northeastern Iran.  Two hundred and thirteen nested-sampling quadrats were established and the abundance of the plants was recorded. Vegetation sampling was carried out from 2014 till 2016, foll...

Journal: :بوم شناسی کشاورزی 0
علی قنبری زهره قویدل رضا قربانی قدریه محمودی

in order to study the different levels of irrigation on diversity, density and compound of weed species in corn field, experiment was conducted at agricultural research station, ferdowsi university of mashhad during growing season of 2008-2009. the experiment was with four levels of irrigation (6130, 7290, 8800 and 12330 m3) and four levels of weed control (complete control, broad-leaves contro...

Journal: :جنگل و فرآورده های چوب 0
مجید لقمانپور ؛ دانشجوی دکتری جنگل داری، دانشگاه ملی اراضی ارمنستان، کارشناس سازمان جنگل ها، مراتع و آبخیزداری، تهران، ایران محسن الهی دانش آموختة کارشناسی ارشد جنگل داری، دانشکدة منابع طبیعی، تربیت مدرس، نور، ایران علی یخکشی استاد دانشکدة منابع طبیعی، دانشگاه علوم کشاورزی و منابع طبیعی ساری، ساری، ایران ژهائیر واردانیان استاد دانشگاه ملی اراضی، ایروان، ارمنستان

in order to investigate the effects of  management models on the diversity of wooden species, forests of third series of shiler, the first division mehrbanrud watershed and third and fourth series of eight division of behshahr – neka townships were studied with participatory and governmental management respectively. the diversity of the wooden species have been evaluated by diversity parametric...

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