نتایج جستجو برای: shahriyar rangelands

تعداد نتایج: 2395  

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...

2009
Pierre Hiernaux Augustine Ayantunde Adamou Kalilou Eric Mougin Frédéric Baup Manuela Grippa Bakary Djaby

To document trends in land use and herbaceous production, 71 field sites sampled among cropped fields, fallow fields and rangelands in the Fakara region (Niger) were monitored from 1994 to 2006. The overall trend in land use confirmed the historical increase of the cropped areas since mid 20th century, at an annual rate of 2% from 1994 to 2006. This trend is the result of changes in the relativ...

2003
John Tanaka

Although cheatgrass (Bromus tectorum) has been widely distributed across western rangelands for >70 years, the full ecologic and economic impacts of this non-native invasive plant have not yet occurred. Unfortunately, several independent lines of evidence indicate that the rate at which acreage becomes infested with cheatgrass is increasing rapidly. Furthermore, the invasion and spread of a num...

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