نتایج جستجو برای: polour rangelands

تعداد نتایج: 2381  

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه علوم کشاورزی و منابع طبیعی گرگان - دانشکده مرتع و آبخیزداری و شیلات و محیط زیست 1391

مراتع حدود نیمی از خشکی های جهان را در بر دارند و پوشش گیاهی آن در نتیجه تأثیر متقابل محیط و موجودات زنده به وجود آمده است و به عنوان یک اکوسیستم طبیعی مدیریت می شوند. علاوه بر مراتع، راه ها در عصر حاضر نیز از اجزا مهم و زیرساخت های اصلی زندگی نوین و توسعه کشورها به شمار می روند. جاده ها ساخته دست بشر هستند و جوامع گیاهی کنار جاده تحت تأثیر ساخت و ساز قرار دارند. پوشش "رودرال" به مجموعه ای از پ...

Journal: :The Rangeland Journal 2019

Journal: :Journal of Range Management 1993

2003
K. P. Kirkman P. C. de Faccio Carvalho

Rangelands essentially comprise geographical regions dominated by grass with or without scattered woody plants. Rangelands are often considered to function primarily as feed for livestock. In this view, conservation and biodiversity issues are secondary. The alternate view involves recognising rangelands as a biome without a specific function, but where there is an implied responsibility for in...

Journal: :Animal : an international journal of animal bioscience 2014
F Accatino R Sabatier C De Michele D Ward K Wiegand K M Meyer

Rangelands provide the main forage resource for livestock in many parts of the world, but maintaining long-term productivity and providing sufficient income for the rancher remains a challenge. One key issue is to maintain the rangeland in conditions where the rancher has the greatest possibility to adapt his/her management choices to a highly fluctuating and uncertain environment. In this stud...

2015
Penelope J. Mograbi Barend F. N. Erasmus E. T. F. Witkowski Gregory P. Asner Konrad J. Wessels Renaud Mathieu David E. Knapp Roberta E. Martin Russell Main

Woody biomass dynamics are an expression of ecosystem function, yet biomass estimates do not provide information on the spatial distribution of woody vegetation within the vertical vegetation subcanopy. We demonstrate the ability of airborne light detection and ranging (LiDAR) to measure aboveground biomass and subcanopy structure, as an explanatory tool to unravel vegetation dynamics in struct...

2015
Michael Elias Oliver Hensel Uwe Richter Christian Hülsebusch

Conversion of rangelands into cultivated land is one of the main challenges affecting the management of rangelands in Ethiopia. In order to inform policy makers about trends in land-use conversion, this study examined the drivers, trends, and impacts of land conversions in five locations selected in the Borana rangelands of Southern Ethiopia. This study integrated survey interviews from agro-pa...

2016
Joseph O. Ogutu Hans-Peter Piepho Mohamed Y. Said Gordon O. Ojwang Lucy W. Njino Shem C. Kifugo Patrick W. Wargute

There is growing evidence of escalating wildlife losses worldwide. Extreme wildlife losses have recently been documented for large parts of Africa, including western, Central and Eastern Africa. Here, we report extreme declines in wildlife and contemporaneous increase in livestock numbers in Kenya rangelands between 1977 and 2016. Our analysis uses systematic aerial monitoring survey data colle...

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