Misplaced Pages

Revision as of 06:37, 4 March 2014

This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Rangeland" – news · newspapers · books · scholar · JSTOR (March 2014) (Learn how and when to remove this message)

Rangelands are vast natural landscapes in the form of grasslands, shrublands, woodlands, wetlands, and deserts. Types of rangelands include tallgrass and shortgrass prairies, desert grasslands and shrublands, woodlands, savannas, chaparrals, steppes, and tundras. Rangelands do not include barren desert, farmland, closed canopy forests, or land covered by solid rock, concrete and/or glaciers.

Rangelands are distinguished from pasture lands because they grow primarily native vegetation, rather than plants established by humans. Rangelands are also managed principally with extensive practices such as managed livestock grazing and prescribed fire rather than more intensive agricultural practices of seeding, irrigation, and the use of fertilizers.

Grazing is an important use of rangelands but the term "rangeland" is not synonymous with "grazinglands". There are areas of rangeland that are not grazed and there are grazed areas that are not rangelands. Livestock grazing can be used to manage rangelands by harvesting forage to produce livestock, changing plant composition or reducing fuel loads.

Fire is also an important regulator of range vegetation, whether set by humans or resulting from lightning. Fires tend to reduce the abundance of woody plants and promote herbaceous plants including grasses, forbs, and grass-like plants. The suppression or reduction of periodic wildfires from desert shrublands, savannas, or woodlands frequently invites the dominance of trees and shrubs to the near exclusion of grasses and forbs.

Types of rangeland

Prairie

Prairies are considered part of the temperate grasslands, savannas and shrublands biome by ecologists, based on similar temperate climates, moderate rainfall, and grasses, herbs, and shrubs, rather than trees, as the dominant vegetation type. Temperate grassland regions include the Pampas of Argentina, and the steppes of Eurasia.

Grasslands

Grasslands are areas where the vegetation is dominated by grasses (Poaceae) and other herbaceous (non-woody) plants (forbs). However, sedge (Cyperaceae) and rush (Juncaceae) families can also be found. Grasslands occur naturally on all continents except Antarctica. In temperate latitudes, such as northwest Europe and the Great Plains and California in North America, native grasslands are dominated by perennial bunch grass species, whereas in warmer climates annual species form a greater component of the vegetation.

Steppe

Steppe, in physical geography, refers to a biome region characterized by grassland plain without trees apart from those near rivers and lakes. The prairie (especially the shortgrass and mixed prairie) is an example of a steppe, though it is not usually called such. It may be semi-desert, or covered with grass or shrubs or both, depending on the season and latitude. The term is also used to denote the climate encountered in regions too dry to support a forest, but not dry enough to be a desert.

Pampas

Pampas are the fertile South American lowlands that include the Argentine provinces of Buenos Aires, La Pampa, Santa Fe, Entre Ríos and Córdoba, most of Uruguay, and the State of Rio Grande do Sul, in the southernmost end of Brazil covering more than 750,000 km (289,577 sq mi). These vast plains are only interrupted by the low Ventana and Tandil hills near Bahía Blanca and Tandil (Argentina), with a height of 1,300 m (4,265 ft) and 500 m (1,640 ft) respectively. The climate is mild, with precipitation of 600 mm (23.6 in) to 1,200 mm (47.2 in), more or less evenly distributed through the year, making the soils appropriate for agriculture. This area is also one of the distinct physiography provinces of the larger Paraná-Paraguay Plain division. These plains contain unique wildlife because of the different terrains around it. Some of this wildlife includes the rhea, the badger, and the prairie chicken.

Scrubland

Scrubland is a plant community characterized by vegetation dominated by shrubs, often also including grasses, herbs, and geophytes. Shrubland may either occur naturally or be the result of human activity. It may be the mature vegetation type in a particular region and remain stable over time, or a transitional community that occurs temporarily as the result of a disturbance, such as fire. A stable state may be maintained by regular natural disturbance such as fire or browsing. Shrubland may be unsuitable for human habitation because of the danger of fire. The term "shrubland" was first coined in 1903.

Woodland

Woodland is a low-density forest forming open habitats with plenty of sunlight and limited shade. Woodlands may support an understory of shrubs and herbaceous plants including grasses. Woodland may form a transition to shrubland under drier conditions or during early stages of primary or secondary succession. Higher densities and areas of trees, with largely closed canopy, provide extensive and nearly continuous shade are referred to as forest.

Savanna

Savanna is a grassland ecosystem characterized by the trees being sufficiently small or widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to support an unbroken herbaceous layer consisting primarily of C4 grasses.

Desert

Desert is a landscape or region that receives an extremely low amount of precipitation, less than enough to support growth of most plants. Deserts are defined as areas with an average annual precipitation of less than 250 millimetres (10 in) per year, or as areas where more water is lost by evapotranspiration than falls as precipitation. In the Köppen climate classification system, deserts are classed as BWh (hot desert) or BWk (temperate desert). In the Thornthwaite climate classification system, deserts would be classified as arid megathermal climates.

Tundra

Tundra is a biome where the tree growth is hindered by low temperatures and short growing seasons. The term tundra comes through Russian тундра from the Kildin Sami word tūndâr "uplands," "treeless mountain tract." There are three types of tundra: Arctic tundra, alpine tundra, and Antarctic tundra In tundra, the vegetation is composed of dwarf shrubs, sedges and grasses, mosses, and lichens. Scattered trees grow in some tundra. The ecotone (or ecological boundary region) between the tundra and the forest is known as the tree line or timberline.

North American rangelands

Canada

Rangeland is a prominent feature of rural Canada. A provincial jurisdiction, administration and policy regarding range use varies across the country. Like many Commonwealth countries, public tenures on crown land for the purpose of range activities is common in geographically compatible areas. Reconciling the economic needs of ranchers and the need for environmental conservation is one of the primary themes in modern range discourse.

Certain rangelands are preserved as provincially-protected areas similar to parks, others are managed as community resources. For example, in Alberta since 2003 there has been legistation allowing the creation of "Heritage Rangelands" within the parks system. As of 2012 there were 2 heritage rangelands and 6 proposed future heritage rangelands run by Alberta Parks. There are also 32 provincial grazing reserves located throughout Alberta administered as public lands by Alberta Sustainable Resource Development. The federal government also owned several "Community Pastures" in Western Canada that were reclaimed lands suffering erosion during the 1930s. As of 2012 all of the community pastures are being closed or transferred the provinces.

United States

Of the land within the United States borders, 36% is considered rangelands. The western side of the United States is 53% rangeland. Around 399 million acres (1,610,000 km²) of rangeland are privately owned. The Bureau of Land Management manages about 167 million acres (676,000 km²) of publicly owned rangeland, with the United States Forest Service managing approximately 95 million acres (380,000 km²) more. Ranchers may lease portions of this public rangeland and pay a fee based on the number and type of livestock and the period for which they are on the land.

Historically much of the land in the western United States was used for grazing and much of some states still is. In many of those states, such as Arizona, an open-range law applies which requires a land owner to fence cattle out rather than in; thus cattle are theoretically allowed to roam free. In modern times open-range laws can conflict with urban development as occasional stray cows, bulls, or even herds wander into subdivisions or onto highways.

North American rangelands - grasslands

• Tall Grass Prairie
• Mixed Grass Prairie
• Short Grass Prairie
• Pacific Bunchgrass
• Annual Grasslands

North American rangelands - shrublands

• Sagebrush Steppe
• Salt Desert Shrublands
• Desert Shrublands

World's rangelands

The different types of rangeland come together to form about 70% (excluding Antarctica) of the Earth's surface.

Australia

About 75% of Australia’s land mass is Rangeland. 53 of Australia's 85 bioregions have rangelands. In Western Australia, rangelands cover about 87% of the state’s 2.5 million square kilometres. Australian Rangelands support most of their economy. Rangelands support Australia's valuable mining industry ($12 billion/yr), tourism ($2 billion/yr), pastoralism ($5.5 billion/yr – cattle $4.4 billion & sheep $1 billion). Australia's rangelands include a diverse group of relatively undisturbed ecosysterms such as; tropical savannas, woodlands, shrublands, grasslands and deserts. Rangelands in Australia cover low rainfall and variable climates which include; arid semi arid and seasonally high rainfall areas. Australian rangelands are important in; biodiversity, income, social and cultural heritage, sub-artesian water sources and major river systems, clean and green food and fiber production, and carbon storage. Rangelands contain a wealth of biodiversity including a total of 1800 types of plants and 605 vertebrate animals currently identified. Rangelands are managed by Australia's Department of Agriculture, Fisheries and Forestry (DAFF) and the ESRM Programs on the local level

South America

Rangelands in South America are located in regions with climate ranging from arid to sub-humid. Annual precipitation in these areas ranges from approximately 150 to 1500 mm (6–60 inches). Within South America, rangelands cover about 33% of the total land area. South American rangelands include; grasslands, shrublands, savannas,and hot and cold deserts. Rangelands in South America exclude hyperarid deserts. Examples of the South American rangelands include the; Patagonian Steppe, the Monte, the Pampas, the "Lianos" or "Cerrado," the "Chaco" and the "Caatinga." The change in the intensity and location of tropical thunderstorms and other weather patterns is the driving force in the climates of southern South America.

Africa

In Kenya, rangelands make up for 85% of the land surface area,and are largely inhabited by nomadic pastoralists who are largely dependent on livestock. This movement often brings along an incursion of different diseases with the common one being the rinderpest virus in the Kenyan wildlife population from the Somalian ecosystem.

Asia-China

In the past, rangelands in western China supported a pastoral economy and large wildlife populations. Now the rangelands have shrunk due to population growth, economic, government, and social factors. Rangeland types in China include; Semi-desert, Dry Alpine Grasslands, Alpine Dwarf Shrub, Wetland types.

Uses of rangeland

Rangelands produce a wide variety of goods and services desired by society, including livestock forage (Grazing), wildlife habitat, water, mineral resources, wood products, wildland recreation, open space and natural beauty. The geographic extent and many important resources of rangelands make their proper use and management vitally important to people everywhere.

Gallery

• Palouse Hills of Washington
• Sonoran Desert
• Konza Prairie
• Buffalo grazing on rangeland in Crook County, Wyoming.
• Triodia Hummock Grasslands
• Savannah in southern Africa
• Caliente Peak, California
• Lake Swan, Nevada

See also

• Applied ecology
• Coastal plain
• Coastal prairie
• Experimental range
• Field
• Forage
• Grassland
• Grass valley
• Holistic management
• Meadow
• Pasture
• Potrero
• Plain
• Prairie
• Range condition scoring
• Savanna
• Steppe
• Veld

References

1. Micropaedia: The New Encyclopaedia Britannica. Vol. 9 (15th ed.). 2010.
2. NASA Earth Observatory webpage
3. "Chapter 12 Scrub Management". Natural England.
4. Merriam-Webster's Collegiate Dictionary, 11th Edition (2003).
5. Werner, Patricia A. (1991). "Introduction". In Patricia A. Werner (ed.). Savanna Ecology and Management: Australian Perspectives and Intercontinental Comparisons. Oxford: Blackwell Publishing. ISBN 978-0-632-03199-3. {{cite book}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
6. What is a desert?
7. According to What is a desert?, the 250 mm threshold definition is attributed to Peveril Meigs.
8. "desert". Encyclopædia Britannica online. Retrieved 2008-02-09.
9. Fredlund, D.G. (1993). Soil Mechanics for Unsaturated Soils (PDF). Wiley-Interscience. ISBN 978-0-471-85008-3. Retrieved 2008-05-21. {{cite book}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
10. Glossary of Meteorology. Megathermal Climate. Retrieved on 2008-05-21.
11. Aapala, Kirsti. "Tunturista jängälle". Kieli-ikkunat. Archived from the original on 2006-10-01. Retrieved 2009-01-19.
12. ^ "The Tundra Biome". The World's Biomes. Retrieved 2006-03-05.
13. "Terrestrial Ecoregions: Antarctica". Wild World. National Geographic. Archived from the original on 2011-10-21. Retrieved 2009-11-02.
14. Landals, Archie (2003). "Heritage Rangelands: A Bold Step to Preserve a Legacy" (PDF). Alberta Wilderness Association. Retrieved 21 July 2013.
15. "Management & Land-use - Legislation & Regulations". Alberta Tourism Parks and Recreation. Retrieved 2013-06-30.
16. "Provincial Grazing Reserves". Alberta Ministry of Environment and Sustainable Resource Development. 27 October 2006. Retrieved 22 July 2013.
17. "Community Pasture Program". Agriculture and Agri-Food Canada. 2013-06-21. Retrieved 2013-06-30.
18. ^ "What is Range". Cnr.uidaho.edu. Retrieved 2010-12-22.
19. "Arizona Rethinking Open Range Laws" article by Marc Lacey in The New York Times October 11, 2010. Retrieved October 13, 2010.
20. ESRM Australian Rangelands Page

External links

• Rangelands 1979-2003 archive - freely available volumes published by The Society For Range Management
• Society for Range Management
• Bureau of Land Management
• USDA Forest Service
• University of Idaho - Rangeland Ecology and Management
• Information about Australian Rangelands

• Grasslands
• Temperate grasslands, savannas, and shrublands
• Geological history of Earth