نتایج جستجو برای: national parks
تعداد نتایج: 399103 فیلتر نتایج به سال:
Western Canada is experiencing an unprecedented outbreak of the mountain pine beetle (MPB). The MPB has the potential to impact some of Canada's national parks by affecting park ecosystems and the visitor experience. Controls have been initiated in some parks to lessen the impacts and to prevent the beetle from spreading beyond park boundaries. We examine the perception of ecological risk assoc...
The tourism in rural areas and national parks can be regarded as a very sensitive economic factor. On the one hand eco-tourism regions and especially national parks have to present their natural environment and fascinate landscape. On the other hand they have to guide tourist streams to avoid negative effects on their assets. This paper will briefly discuss the current situation of the digital ...
internationally, one of the most important purposes to establish a national park is to protect a unique ecosystem with all its inclusive biota. therefore, this will facilitate the management and protection of the neighboring lands. unfortunately, this trend was reversed in iranian national parks. during recent decades, the land cover changes in protected areas have led to the decrease of the re...
National parks in the United States are protected areas wherein the natural habitat is to be conserved for future generations. Deposition of anthropogenic nitrogen (N) transported from areas of human activity (fuel combustion, agriculture) may affect these natural habitats if it exceeds an ecosystem-dependent critical load (CL). We quantify and interpret the deposition to Class I US national pa...
This study explores the importance of different motivations to visit three types of recreational settings--farms, private forests, and state or national parks. Data were collected via a mail-back questionnaire administered to a stratified random sample of households in Missouri (USA). Descriptive and inferential statistics reveal both similarities and discontinuities in motivations for visiting...
After 50 years of steady increase, per capita visits to U.S. National Parks have declined since 1987. To evaluate whether we are seeing a fundamental shift away from people's interest in nature, we tested for similar longitudinal declines in 16 time series representing four classes of nature participation variables: (i) visitation to various types of public lands in the U.S. and National Parks ...
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