نتایج جستجو برای: rangeland production

تعداد نتایج: 606142  

Journal: :Philosophical transactions of the Royal Society of London. Series B, Biological sciences 2002
Brian H Walker Marco A Janssen

We analyse commercially operated rangelands as coupled systems of people and nature. The biophysical components include: (i) the reduction and recovery of potential primary production, reflected as changes in grass production per unit of rainfall; (ii) changes in woody plants dependent on the grazing and fire regimes; and (iii) livestock and wool dynamics influenced by season, condition of the ...

2009
Temuulen Tsagaan Sankey Keith T. Weber

Extensive livestock production has been Mongolia’s major industry for centuries and traditional nomadic herding lifestyle and Mongolia’s expansive rangelands sustain this industry. After the democratic election and economic liberalization in 1992, formerly state-owned collectives were disbanded and Mongolia’s livestock population was privatized. There was no longer a state institution to formal...

2013
Anna C. Treydte

Livestock production is a key income source in eastern Africa, and 80% of 22 the total agricultural land is used for livestock herding. Hence, ecological and 23 socio-economically sustainable rangeland management is crucial. Our study aimed at 24 selecting operational economic, environmental and social sustainability indicators for three 25 main pastoral (P), agro-pastoral (AP), and landless in...

Journal: :مرتع و آبخیزداری 0
مریم آذرخشی استادیار مجتمع آموزش عالی تربت حیدریه بهنوش فرخ زاده دانشجوی دکتری آبخیزداری دانشگاه تهران محمد مهدوی استاد دانشگاه تهران، دانشکده منابع طبیعی، ایران حسین ارزانی استاد دانشگاه تهران، دانشکده منابع طبیعی، ایران حسن احمدی استاد دانشگاه آزاد اسلامی، واحد علوم و تحقیقات تهران، ایران

iran is located in dry belt of the earth and always involved with drought in different sections. drought has already caused many losses to natural plant cover, agriculture and human society. for drought monitoring, we can use some drought indecies. in this research, the standard index of annual precipitation)siap),sandardized precipitation index (spi) and palmer drought severity index (pdsi) we...

Journal: :Environmental management 2011
Dustin D Johnson Kirk W Davies Peter T Schreder Anna-Marie Chamberlain

Medusahead (Taeniatherum caput-medusae (L.) Nevski) is an exotic annual grass invading rangelands in the western United States. Medusahead is a serious management concern because it decreases biodiversity, reduces livestock forage production, and degrades the ecological function of rangelands. Despite the obvious importance of ranchers as partners in preventing and managing medusahead in rangel...

Journal: :مرتع و آبخیزداری 0
طاهره صادقی شاهرخت کارشناس ارشد مرتع داری، دانشگاه فردوسی مشهد محمد جنگجو دانشیار گروه مرتع و آبخیزداری دانشکده منابع طبیعی و محیط زیست، دانشگاه فردوسی مشهد منصور مصداقی استاد مدعو، دانشکده منابع طبیعی و محیط زیست دانشگاه فردوسی مشهد

rangeland shrubs may provide mechanical facilitation on their understory plants, by protecting themagainst the livestock grazing. however, such a facilitation effect may vary depending on the rangelandutilization rate. in a field research, mechanical facilitation of rangeland shrubs was compared in ahighly grazed, a moderately grazed and an enclosure site; in an arid rangeland, kakhak, gonabad,...

2005
S. Vetter

This paper reviews the predictions and management implications of two current paradigms in the ecology and management of arid and semi-arid rangelands. The equilibrium model stresses the importance of biotic feedbacks such as density-dependent regulation of livestock populations and the feedback of livestock density on vegetation composition, cover and productivity. Range management under this ...

2005
David Correia

This article examines the history of rangeland management on the El Rito District of the Carson National Forest in northern New Mexico. The area became part of the U.S. Forest Service system in the late nineteenth century, when Mexican land grants in the area were not confirmed by U.S. courts. In the 1940s, the Forest Service implemented a series of grazing restrictions in the district. The art...

2000
B. D. Campbell

There is significant uncertainty about the effects of global change on the vegetation and animal productivity of pasture and rangeland ecosystems. This paper presents a synthesis of progress made between 1994 and 1999 in the Global Change and Terrestrial Ecosystems (GCTE) Pastures and Rangelands Core Research Project 1 (CRP1) network, a world-wide network of 83 full-time equivalent researchers ...

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