نتایج جستجو برای: especially in arid and semiarid regions

تعداد نتایج: 21755242  

Journal: :desert 2009
b. rasooli m. jafari

determination of the relationships between soil and plant cover indispensible in the in planning and managementof the arid regions, the aim being to revitalize plant cover, conserve soil and to combat desertification. among factorsaffecting plant cover, particularly in arid and semiarid areas are soil traits. during the present study, the effect ofhaloxylon aphyllum cultivation on soil physioch...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه شهید مدنی آذربایجان - دانشکده ادبیات و زبانهای خارجی 1389

according to coates’s (2004, as cited in zhang, 2010) definition of "conversational dominance" (p.111), it refers to the phenomenon of a speaker dominating others in interaction. specifically, it means how a speaker makes use of certain strategies to get the floor and maintain the floor. thus, the amount of talk is the main measurement for the dominance of the conversation. whether a speaker do...

Journal: :محیط زیست طبیعی 0
علیرضا خداشناس مرکز تحقیقات کشاورزی و منابع طبیعی خراسان رضوی، ایران علیرضا کوچکی گروه زراعت، دانشکده کشاورزی، دانشگاه فردوسی مشهد، ایران پرویز رضوانی مقدم گروه زراعت، دانشکده کشاورزی، دانشگاه فردوسی مشهد، ایران امیر لکزیان گروه خاکشناسی، دانشکده کشاورزی، دانشگاه فردوسی مشهد، ایران

soil biodiversity is the origin of considerable goods for maintenance and extension of above ground biodiversity and environmental soundness. this study was carried out in shirvan, mashhad and gonabad, three regions of razavi and northern khorasan provinces, to determine soil characteristics and biodiversity in natural systems of arid and semi-arid regions. in each studied system, 10 locations ...

2017
Jose Luis Villaseñor Ana Botanic Garden JOSE LUIS VILLASENOR

The flora of Mexico includes about 119 endemic or nearly endemic genera of Asteraceae. In this study, the genera are listed and their distribution patterns among the floristic provinces of Mexico analyzed. Results indicate strong affinities of the endemic genera for mountainous and arid or semiarid regions. Since its first appearance in Mexico, the Asteraceae diversified into these kinds of hab...

Journal: :Proceedings of the National Academy of Sciences of the United States of America 2016
Michael I Bird Damien O'Grady Sean Ulm

The Pleistocene global dispersal of modern humans required the transit of arid and semiarid regions where the distribution of potable water provided a primary constraint on dispersal pathways. Here, we provide a spatially explicit continental-scale assessment of the opportunities for Pleistocene human occupation of Australia, the driest inhabited continent on Earth. We establish the location an...

Journal: :international journal of advanced biological and biomedical research 2014
mahdi zare korosh ordookhani abouzar emadi arash azarpanah

objective: soil salinity is one of the major worldwide environmental constraints affecting agricultural production in arid and semiarid regions. lack of proper management of water and soil resources lead to increase soil salinity and reduce soil fertility. on the other hand, it seems simple and cheap method of measuring soil salinity is necessary. the aim of this study was to determine the rela...

Journal: Desert 2016

Green space is one of the important infrastructures for keeping natural life and sustainability in modern urbanism and it provides excellent recreational opportunities for the people in the society. However, there are limiting factors in green space development, especially in arid regions, including extreme weather and soil temperatures, low average rainfall, drought, and high potential for eva...

Journal: :molecular biology research communications 2013
davoud fadakar hamid rezaei maryam naseri masoumeh mirzakhah saeid naderi

persian gazelle, gazella subgutturosa, exists throughout arid and semiarid regions of iran and has a key role in these frail ecosystems. habitat degradation and population decline has placed it on the list of vulnerable species in 2008. the phylogenetic relationships of three persian gazelle populations in the central part of iran (i.e. ghamishlou national park and wildlife refuge, mouteh wildl...

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