Natur, klima. Biodiversitet. Fauna
og flora: Fisk. Fugle.
Nature, climate. Flora and fauna: Botanical gardens. Fish. Birds. Coral reefs. Wetlands
Flore et faune: Poissons. Oiseaux. Les récifs coralliens.
Les zones humides.
Flora y fauna: Fish. Pájaros. Los arrecifes de coral. Los
Natur, Klima. Flora und Fauna: Botanische Gärten. Fisch. Vögeln. Korallenriffe. Feuchtgebiet,
Check-list of North American birds : the species of birds of
North America from the Arctic through Panama, including the West
Indies and Hawaiian Islands. / : The Committee on Classification
and Nomenclature of the American Ornithologists' Union 1983.
North American Important Bird Areas: A Directory of 150 Key
Conservation Sites. / : Commission for Environmental Cooperation,
Nordamerikansk natur i international lovgivning, folkeret / North American nature in
International Network of Basin Organizations / Det internationale netværk af flodbassin organisationer.
The Transboundary Freshwater Dispute Database, 2002.
Atlas of International Freshwater Agreements: North America.
Oregon State University. United Nations Environment Programme.
Treaty Between The United States and Great Britain Relating to
Boundary Waters, and Questions Arising Between the United States
and Canada (1909 Boundary Waters Treaty)
Naturhistorie: Ornithological bibliography. / : Elliott
List of fauna publications relating to North American bibliography.
1878. (From Miscellaneous publications of the U.S. Geological
Survey, no. 11) -- Second installment of American ornithological
bibliography. (From Bulletin of the U.S. Geological and
Geographical Survey, v. 5, no. 2) -- Third installment of American
ornithological bibliography. 1880. (From Bulletin of the U.S.
Geological & Geographical Survey of the Territories, v. 5, no.
4) -- Fourth installment of ornithological bibliography. 1880.
(From Proceedings of the United States National Museum, v. 2
vulkaner, jordskælv og ørkenområder:
Geology: Mountains, volcanoes, earthquakes and desert areas
Géologie: Montagnes, volcans, tremblements de terre et les
Geología: Montañas, volcanes, terremotos y zonas
Geologie: Berge, Vulkane, Erdbeben und Wüstengebiete
Geologihistorie: Lake Agassiz: About 12,000 years ago, the
glaciers melted back to the topographic divide (near the North
Dakota/South Dakota border). Glacial meltwater was trapped and
accumulated, creating Lake Agassiz.
Ørkenområder: Chihuahuan Desert.
The Otero Mesa
The Chihuahuan Desert extends southward from New Mexico, Texas and
Arizona into the Mexican Plateau. It covers an area of 250,000
square miles and is considered to be among the most biologically
rich and diverse desert eco-regions in the world. The area is home
to Pronghorn Antelope, migratory songbirds and independent cattle
ranches that have been in operation for generations.
Despite local outrage and a 2005 law suit filed by New Mexico's
governor against the Bush administration, the Bureau of Land
Management has made the decision to nearly double the acreage
available for oil and gas development on Otero Mesa. If it is
turned into a full-scale oil and gas field, the Wilderness and much
of the wildlife that live there will be threatened by groundwater
pollution. Current drilling requires the use of a number of
chemical agents (many of which are suspected carcinogens) that are
used the entire length of a drilling process. Plant dieback under exceptional drought driven by elevation, not
by plant traits, in Big Bend National Park, Texas, USA. by
Waring, Elizabeth F.; Schwilk, Dylan W., 2014 PeerJ, volume 2.
In 2011, Big Bend National Park, Texas, USA, experienced the most
severe single year drought in its recorded history, resulting in
significant plant mortality. We used this event to test how
perennial plant response to drought varied across elevation, plant
growth form and leaf traits. In October 2010 and October 2011, we
measured plant cover by species at six evenly-spaced elevations
ranging from Chihuahuan desert (666 m) to oak forest in the Chisos
mountains (1,920 m). We asked the following questions: what was the
relationship between elevation and stem dieback and did
susceptibility to drought differ among functional groups or by leaf
traits? In 2010, pre-drought, we measured leaf mass per area (LMA)
on each species. In 2011, the percent of canopy dieback for each
individual was visually estimated. Living canopy cover decreased
significantly after the drought of 2011 and dieback decreased with
elevation. There was no relationship between LMA and dieback within
elevations. The negative relationship between proportional dieback
and elevation was consistent in shrub and succulent species, which
were the most common growth forms across elevations, indicating
that dieback was largely driven by elevation and not by species
traits. Growth form turnover did not influence canopy dieback;
differences in canopy cover and proportional dieback among
elevations were driven primarily by differences in drought
severity. These results indicate that the 2011 drought in Big Bend
National Park had a large effect on communities at all elevations
with average dieback for all woody plants ranging from 8% dieback
at the highest elevation to 83% dieback at lowest elevations. Transactions of the Symposium on the Biological Resources of the
Chihuahuan Desert Region, United States and Mexico by Wauer,
Roland; Riskind, David. 1977