Treelines differentiate vastly contrasting ecosystems: open tundra from closed forest. Treeline advance has implications for the climate system due to the impact of the transition from tundra to forest ecosystem on carbon (C) storage and albedo. Treeline advance has been seen to increase above-ground C stocks as low vegetation is replaced with trees but decrease organic soil C stocks as old car...

In northwestern Costa Rica, cattle are being used as a "management tool" to reduce the amount of combustible material, mainly dominated by Hyparrhenia rufa, an African grass. This project is being developed within Parque Nacional Palo Verde and Reserva Biológica Lomas Barbudal, both of which form part of the only remaining tropical dry forests in Mesoamerica. To determine the short-term effects...

Doctor Ingeniero de Montes, ICONA Forest Fire Section, Madrid Spain. Abstract: Forest fuels in the Mediterranean ecosystems of Spain are characterized by generalized pyrophytism and large accumulations of woody shrub vegetation. The Forest Service prepared in 1978 a fuel management plan and a program of surveys including: A study on the vegetation's evolution in forests after fires; the experim...

Projected changes in global climate have important ramifications for the future of national parks and other reserves set aside to conserve ecological uniqueness. We explored potential implications of climatic changes on lifeform distribution and growth at Wind Cave National Park (WCNP), South Dakota, which lies on a climatically determined ecotone between grassland and forest. Fire, promoted by...

Southern California kelp forests experienced major losses during the El Nino of 1957-1959. The proximal reason for the decline was ascribed to sea urchin grazing, and the eventual recovery of some forests followed sea urchin control efforts, kelp restoration, and improvements In sewage disposal practices. The very strong El Nirio of 1982-84 allowed us to reexamine hypotheses regarding the inter...

Regeneration and forest durability guarantee is one of the most important aspects of forest sustainability and it should be placed in forest plans priority. To compare regeneration in the two grazed and non-grazed forest, Baghe-shady forest located in Khatam city (it has the preservative regions that they are 20 years old), Yazd province, Central of Iran was selected. For this purpose, 60 sampl...

We examined long-term (10 years) meadow plant community responses to (1) livestock grazing under riparian grazing utilization limits; (2) suspension of livestock grazing; and (3) meadow site wetness and precipitation on the Inyo National Forest, California. Observed trends in meadow plant species richness, diversity, and frequency of soil stabilizing species were not significantly different bet...

Herbivory and fire are natural interacting forces contributing to the maintenance of rangeland ecosystems. Wildfires in the sagebrush dominated ecosystems of the Great Basin are becoming larger and more frequent, and may dramatically alter plant communities and habitat. This synthesis describes what is currently known about the cumulative impacts of historic livestock grazing patterns and short...

Background: Livestock grazing and ‘overabundance’ of large wild herbivores in forested areas have long been perceived as conflicting with the aims of both silviculture and forest conservation; however, certain kinds of herbivory can help to maintain habitat values in forest ecosystems. Management of grazing/browsing in protected forests can, therefore, be a critical tool for biodiversity conser...