نتایج جستجو برای: 2012 agricultural lands as ecological traps for grizzly bears animal conservation 15
تعداد نتایج: 12041691 فیلتر نتایج به سال:
Conservation biologists recognize that a system of isolated protected areas will be necessary but insufficient to meet biodiversity objectives. Current approaches to connecting core conservation areas through corridors consider optimal corridor placement based on a single optimization goal: commonly, maximizing the movement for a target species across a network of protected areas. We show that ...
Throughout the 20th century, many countries created national parks, forests, nature reserves, and sanctuaries to provide benefits that are underproduced on private lands . Private lands are now especially valuable for providing ecological services that publi c lands cannot provide, due to the increasing demands for all uses and the political and economic conflicts associated with allocating pub...
Past research indicates that whitebark pine seeds are a critical food source for Threatened grizzly bears (Ursus arctos) in the Greater Yellowstone Ecosystem (GYE). In recent decades, whitebark pine forests have declined markedly due to pine beetle infestation, invasive blister rust, and landscape-level fires. To date, no study has reliably estimated the contribution of whitebark pine seeds to ...
The International Arid Lands Consortium (IALC) was established in 1990 to promote research, education, and training activities related to the development, management, and reclamation of arid and semiarid lands in the Southwestern United States, the Middle East, and elsewhere in the world. The Consortium supports the ecological sustainability and environmentally sound stewardship of these lands ...
In this study, the influencing factors on farmers' participation in use of soil and water conservation practices were investigated using the farmers' experiences in Shahroud river basin. For achieving this goal was used from multinomial logit model. The required dates are related to year 2011-2012 that by completing the questionnaire from 138 sample farmers were collected. To select the sample ...
Increasing the productivity and conservation of limited water resources in the agricultural sector, especially in the agricultural sub-sectors, is closely related to the revision of the traditional approaches of production system in the agricultural sector of developing countries. The aim of this study was to develop the optimal combination of crop production in Varamin Agricultural and Animal ...
Agriculture is being challenged to provide food, and increasingly fuel, for an expanding global population. Producing bioenergy crops on marginal lands--farmland suboptimal for food crops--could help meet energy goals while minimizing competition with food production. However, the ecological costs and benefits of growing bioenergy feedstocks--primarily annual grain crops--on marginal lands have...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید