نتایج جستجو برای: livestock ecosystem

تعداد نتایج: 104389  

2013
E. A. Taha

Livestock fodder needs in nearly all developing countries now exceed the sustainable yield of rangelands and other forage resources. In Africa, overgrazing has reduced range productivity virtually everywhere. It is important to provide animals with adequate nutrition to ensure the high productive and reproductive performance. Meanwhile, it is necessary to avoid the deterioration of the pasturel...

2017
Karsten Wesche Vroni Retzer V. Retzer

This paper tests predictions derived from the non-equilibrium theory of rangeland science. Data were collected in livestock enclosures situated in the relatively moist desert steppes of the Gobi Gurvan Saykhan region of southern Mongolia from 2000 to 2003. Plant community composition and species’ richness in enclosures showed clear differences between years, but these were equally strong in ung...

Journal: :Science 2011
Wilfred O Odadi Moses K Karachi Shaukat A Abdulrazak Truman P Young

Savannas worldwide are vital for both socioeconomic and biodiversity values. In these ecosystems, management decisions are based on the perception that wildlife and livestock compete for food, yet there are virtually no experimental data to support this assumption. We examined the effects of wild African ungulates on cattle performance, food intake, and diet quality. Wild ungulates depressed ca...

Journal: :Conservation biology : the journal of the Society for Conservation Biology 2007
Rurik List Gerardo Ceballos Charles Curtin Peter J P Gogan Jesús Pacheco Joe Truett

Ecologists and conservationists have long assumed that large grazers, including bison (Bison bison), did not occur in post-Pleistocene southwestern North America. This perception has been influential in framing the debate over conservation and land use in the northern Chihuahuan Desert. The lack of an evolutionary history of large grazers is being used to challenge the validity of ranching as a...

2009

The global abundance of N fertilizer has dramatically increased agricultural productivity. However, when N escapes to the atmosphere as ammonia (NH 3 ) gas, NH 3 loss can cause undesirable effects. In addition to a loss of a valuable resource, it can have negative impacts on air quality, ecosystem productivity, and human health. Animal production is the largest source of NH 3 emission in North ...

Journal: :Ecological applications : a publication of the Ecological Society of America 2010
Ricardo M Holdo Kathleen A Galvin Eli Knapp Stephen Polasky Ray Hilborn Robert D Holt

Migratory ungulates may be particularly vulnerable to the challenges imposed by growing human populations and climate change. These species depend on vast areas to sustain their migratory behavior, and in many cases come into frequent contact with human populations outside protected areas. They may also act as spatial coupling agents allowing feedbacks between ecological systems and local econo...

2013
Scott E. Henke

Coyotes (Canis latrans) are often removed from an area because of their predatory nature, regardless of the effect such removal may have on the ecosystem. Research results concerning ecosystem changes due to coyote removal appear ambiguous; however, differing lengths of coyote control can produce different results. Short-term coyote removal efforts (5 6 months) typically have not resulted in in...

2017
Erik Lehnhoff Zachariah Miller Perry Miller Stephen Johnson Tessa Scott Patrick Hatfield Fabian D. Menalled

Organic agricultural production has become a major economic and cultural force. However, in water-limited environments the tools used for weed control and nutrient supply, namely tillage and cover crops, may not be environmentally or economically sustainable as tillage damages soil and cover crops use valuable water. Thus, a major challenge has been finding appropriate ways to minimize tillage ...

Journal: :Revue scientifique et technique 2005
M L Madan

In most developing countries, biotechnological applications relating to livestock need to be suitable for animal owners who are resource-poor small-scale operators who own little or no land and few animals. Livestock is becoming increasingly important to economic growth in developing countries and the application of biotechnology is largely dictated by commercial considerations and socio-econom...

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