Overgrazing occurs when plants are exposed to intensive grazing for extended periods of time, or without sufficient recovery periods. It can be caused by either livestock in poorly managed agricultural applications, game reserves, or nature reserves, it can be caused by immobile, travel restricted populations of native or non-native wild animals. However, "overgrazing" is a controversial concept, based on equilibrium system theory. A strong indicator of overgrazing is where additional feed needs to be brought in from outside the farm to support livestock through the winter. Traditionally this feed was sourced on the farm, with fewer animals being kept and some fields being used for hay and silage production. Modern farm businesses choose to keep more animals than their land can support alone, buying in external feed to offset this, it reduces the usefulness and biodiversity of the land and is one cause of desertification and erosion. Overgrazing is seen as a cause of the spread of invasive species of non-native plants and of weeds.
It is reversed or prevented by moving grazers in large herds, such as the American bison of the Great Plains, or migratory Wildebeests of the African savannas, or by holistic planned grazing. Sustainable grassland production is based on grass and grassland management, land management, animal management and livestock marketing. Grazing management, with sustainable agriculture and agroecology practices, is the foundation of grassland-based livestock production since it affects both animal and plant health and productivity. There are several new grazing models and management systems that attempt to reduce or eliminate overgrazing like Holistic management and Permaculture One indicator of overgrazing is that the animals run short of pasture. In some regions of the United States under continuous grazing, overgrazed pastures are predominated by short-grass species such as bluegrass and will be less than 2-3 inches tall in the grazed areas. In other parts of the world, overgrazed pasture is taller than sustainably grazed pasture, with grass heights over 1 meter and dominated by unpalatable species such as Aristida or Imperata.
In all cases, palatable tall grasses such as orchard grass are non-existent. In such cases of overgrazing, soil may be visible between plants in the stand, allowing erosion to occur, though in many circumstances overgrazed pastures have a greater sward cover than sustainably grazed pastures. Under rotational grazing, overgrazed plants do not have enough time to recover to the proper height between grazing events; the animals resume grazing before the plants have restored carbohydrate reserves and grown back roots lost after the last defoliation. The result is the same as under continuous grazing: in some parts of the United States tall-growing species die and short-growing species that are more subject to drought injury predominate the pasture, while in most other parts of the world tall, drought tolerant, unpalatable species such as Imperata or Aristida come to dominate; as the sod thins, weeds encroach into the pasture in some parts of the United States, whereas in most other parts of the world overgrazing can promote thick swards of native unpalatable grasses that hamper the spread of weeds.
Another indicator of overgrazing in some parts of North America is that livestock run out of pasture, hay needs to be fed early in the fall. In contrast, most areas of the world do not experience the same climatic regime as the continental United States and hay feeding is conducted. Overgrazing is indicated in livestock performance and condition. Cows having inadequate pasture following their calf's weaning may have poor body condition the following season; this may reduce the vigor of cows and calves at calving. Cows in poor body condition do not cycle as soon after calving, which can result in delayed breeding; this can result in a long calving season. With good cow genetics, ideal seasons and controlled breeding 55% to 75% of the calves should come in the first 21 days of the calving season. Poor weaning weights of calves can be caused by insufficient pasture, when cows give less milk and the calves need pasture to maintain weight gain. Overgrazing increases soil erosion. Reduction in soil depth, soil organic matter and soil fertility impair the land's future natural and agricultural productivity.
Soil fertility can sometimes be mitigated by applying organic fertilizers. However, the loss of soil depth and organic matter takes centuries to correct, their loss is critical in determining the soil's water-holding capacity and how well pasture plants do during dry weather. Native plant grass species, both individual bunch grasses and in grasslands, are vulnerable. In the continental United States, to prevent overgrazing, match the forage supplement to the herd's requirement; this means. Another potential buffer is to plant warm-season perennial grasses such as switchgrass, which do not grow early in the season; this reduces the area that the livestock can use early in the season, making it easier for them to keep up with the cool-season grasses. The animals use the warm-season grasses during the heat of the summer, the cool-season grasses recover for fall grazing; the grazing guidelines in the table are for cool-season forages. When using continuous grazing, manage pasture height at one-half the recommended turn-in height for rotational grazing to optimize plant health.
The growth habit of some forage species, such as alfalfa, does not permit their survival under continuous grazing. When managing for legumes in the stand, it is beneficial to use rotational grazing and graze t
Wolfgang Kraushaar is a political scientist and historian. After a residency at the Hamburger Institut für Sozialforschung from the 1980's until 2015. In 2015 he continued his research at the Hamburg Foundation for the Promotion of Science and Culture in Hamburg, Germany. Kraushaar grew up in the German village of Niederruf in Germany. After finishing the König-Heinrich-Schule in Fritzlar, Germany, in 1968 he studied political sciences and German studies in Frankfurt. From 1974-75 he was the chairman of AStA and took a residency at the Hamburger Institut für Sozialforschung since 1987. In 2015 he continued his work at the Hamburg Foundation for the Promotion of Science and Culture in Hamburg, Germany, he focuses on the analysis of protest and political opposition in the Federal Republic of Germany and the German Democratic Republic during the period from 1949–1990 the protests of 1968, the Red Army Faction and K-Gruppen. He furthermore maintains a focus on national and international protest movements and extremism, pop-culture and modern media.
Die Revolution der 68er – was war links?, in: Robertson-von Trotha, Caroline Y.: Herausforderung Demokratie. Demokratisch, gut?, Baden-Baden 2011. ISBN 978-3-8329-5816-9 Die RAF und der linke Terrorismus. Hamburger Edition, Hamburg 2006. Die Bombe im Jüdischen Gemeindehaus. Hamburger Edition, Hamburg 2005. ISBN 3-936096-53-8 Fischer in Frankfurt. Karriere eines Außenseiters. Hamburger Edition, Hamburg 2001. ISBN 3-930908-69-7 Linke Geisterfahrer - Denkanstöße für eine antitotalitäre Linke. Verlag Neue Kritik, Frankfurt 2001. ISBN 3-8015-0320-8 1968 als Mythos, Chiffre und Zäsur. Hamburger Edition, Hamburg 2000. ISBN 3-930908-59-X 1968 - Das Jahr, das alles verändert hat. Piper, München 1998. Frankfurter Schule und Studentenbewegung - Von der Flaschenpost zum Molotowcocktail. Bd. I-III. Rogner & Bernhard, Hamburg 1998. Die Protest-Chronik 1949-1959 - Eine illustrierte Geschichte von Bewegung, Widerstand und Utopie. Bd. I-IV. Rogner & Bernhard bei Zweitausendeins, Hamburg 1996.: Frankfurter Schule und Studentenbewegung.
Von der Flaschenpost zum Molotowcocktail. 3 Bände. Rogner & Bernhard, Hamburg 1998, ISBN 3-8077-0348-9. 1968 – Das Jahr, das alles verändert hat. Piper, München 1998, ISBN 3-492-04058-6. 1968 als Mythos, Chiffre und Zäsur. Hamburger Edition, Hamburg 2000, ISBN 3-930908-59-X. Linke Geisterfahrer. Denkanstöße für eine antitotalitäre Linke. Neue Kritik, Frankfurt 2001, ISBN 3-8015-0320-8. Fischer in Frankfurt. Karriere eines Außenseiters. Hamburger Edition, Hamburg 2001, ISBN 3-930908-69-7.: Rudi Dutschke, Andreas Baader und die RAF. Hamburger Edition, Hamburg 2005, ISBN 3-936096-54-6. Die Bombe im Jüdischen Gemeindehaus. Hamburger Edition, Hamburg 2005. ISBN 3-936096-53-8.: Die RAF und der linke Terrorismus. 2 Bände. Hamburger Edition, Hamburg 2006, ISBN 3-936096-65-1. Achtundsechzig. Eine Bilanz. Propyläen, Berlin 2008, ISBN 978-3-549-07334-6. Verena Becker und der Verfassungsschutz. Hamburger Edition, Hamburg 2010, ISBN 978-3-86854-227-1. Der Aufruhr der Ausgebildeten: Vom Arabischen Frühling zu den weltweiten Anti-Banken-Protesten: Vom Arabischen Frühling zur Occupy-Bewegung.
Hamburger Edition, Hamburg 2012, ISBN 978-3-86854-246-2. Der Griff nach der Notbremse – Nahaufnahmen des Protests. Wagenbach, Berlin 2012, ISBN 978-3-8031-2691-7. „Wann endlich beginnt bei Euch der Kampf gegen die heilige Kuh Israel?“ München 1970: über die antisemitischen Wurzeln des deutschen Terrorismus. Rowohlt, Reinbek 2013, ISBN 978-3-498-03411-5. Die blinden Flecken der RAF. Stuttgart 2017, ISBN 978-3-608-98140-7. Die Blinden Flecken der RAF, Bundeszentrale für politische Bildung, Bonn, 2018 1968. Hundert Seiten, Ditzingen 2018,ISBN 978-3-15-020452-8 Die blinden Flecken der 68er-Bewegung, Stuttgart 2018, ISBN 978-3608981414 Die 68er-Bewegung international - Eine illustrierte Chronik 1960-1969,Bd I-IV, Stuttgart 2018, ISBN 978-3608962925. Wolfgang Kraushaar online
St George's Church is a Church of England church on the Isle of Portland, built between 1754 and 1766 to replace St. Andrew's which had fallen into disuse and was no longer suitable as a place of worship. During the 1960s a restoration of the church took place under the stewardship of a group formed to protect the church, it came under the care of the Churches Conservation Trust, which continues to the present. No longer retained for regular worship, services are held twice annually, on St George's Day and Christmas Day; the history of St. George's Church began in August 1753. A committee of Portlanders was formed to decide whether to put further finances into the dilapidated St. Andrew's Church or to erect a new church at a more accessible position. St. Andrew was prone to landslips. Within two months a decision was made, with a survey of the old church finding that repairs would be at least half the cost of a new building. A year after the completion of the church, a house was built nearby for the parish clerk, this building would become The George Inn.
The church was closed in 1914 for many reasons, fell into further disrepair since that time. In the 1960s however, the church fell under the protection of a newly formed group, the'Friends of St George's Church', who were able to restore the church. Now no longer needed for regular worship, the church is now a redundant church in the care of the Churches Conservation Trust, it was declared redundant on 16 April 1970, was vested in the Trust on 27 October 1971. Designed by architect and quarry merchant Thomas Gilbert, St George's is regarded as one of the most impressive 18th-century churches in Dorset, it is a large church built of Portland stone and has a tower, a nave, transepts, an apse, a kind of'abortive dome' over the crossing. The design is reminiscent of the works of Christopher Wren; the windows are arranged all with simple, broad raised frames that lack moulding. Architect John Vanbrugh called the result "a masculine show", it is designated by English Heritage as a Grade I listed building.
Gilbert was the architect of a number of houses within the local area, including the Grade II* Listed Queen Anne House, his own residence built circa 1720. Grade I listed buildings in Dorset List of churches preserved by the Churches Conservation Trust in South West England Citations Sources