User:Mehmet Karatay/Geography of Mount Kenya

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Mount Kenya
History
Geology
Mountaineering
Climate
Ecology
Geography
People
Names list

Contents 1 Peaks 2 Vegetation Zones 3 Climate 4 Valleys and Rivers 5 Glaciers 5.1 Rock glaciers 6 Periglacial landforms 7 Soils 8 References

[edit] Peaks

Further information: Geology of Mount Kenya and Peak names on Mount Kenya

For mountaineering history see Mountaineering on Mount Kenya

The peaks of Mount Kenya are almost all from a volcanic origin. The majority of the peaks are located near the centre of the mountain. These peaks have an Alpine appearance due to their craggy nature. Typically of Alpine terrain, the highest peaks and gendarmes occur at the intersection of ridges.^[1] The central peaks only have a few mosses, lichens and small alpine plants growing in rock crevices. Further away from the central peaks, the volcanic plugs are covered in volcanic ash and soils. The vegetation growing on these peaks is typical for the vegetation band they are in.

The highest peaks are Batian (5,199 m - 17,058 ft), Nelion (5,188 m - 17,022 ft) and Pt Lenana (4,985 m - 16,355 ft). Batian and Nelion are only XXXm apart but separated by the Gates of Mist gap, which is equally deep. Coryndon Peak (4,960 m - 16,355 ft) is the next highest, but unlike the previous peaks it does not form a part of the central plug.

Other peaks around the central plug include Pt Piggot (4,957 m - 16,266 ft), Pt Dutton (4885 m - 16,027 ft), Pt John (4883 m - 16,016 ft), Pt John Minor (4875 m - 15,990 ft), Pt Peter (4757 m - 15,607 ft), Pt Slade (4750 m - 15,580 ft) and Midget Peak (4700 m - 15,420 ft). All of these have a steep pyramidal form.

Significant craggy outlying peaks include Terere (4714 m - 15,462 ft) and Sendeyo (4704 m - 15,433 ft) which form a pair of twin peaks to the north of the main plug. Together, they form a large parasitic plug.

A ridge to the south of the Gorges valley has many important peaks.

• Rock types of the peaks???

• Pt Pigott (4957 m - 16,266 ft)
• Pt Thompson (4955 m - 15,466 ft)
• Pt Dutton (4885 m - 16,027 ft)
• Pt John (4883 m - 16,016 ft)
• Pt Melhuish (4880 m - 16,010 ft)
• Pt John Minor (4875 m - 15,990 ft)
• Krapf Rognon (4800 m - 15,740 ft)^[2]
• Pt Peter (4757 m - 15,607 ft)
• Pt Slade (4750 m - 15,580 ft)
• Terere (4714 m - 15,462 ft)
• Sendeyo (4704 m - 15,433 ft)
• Midget Peak (4700 m - 15,420 ft)
• The Hat (4639 m - 15,220 ft)
• Delamere Peak
• Macmillan Peak

• Rotundu

[edit] Vegetation Zones

Further information: Ecology of Mount Kenya

Mount Kenya has several distinctive vegetation zones which vary with altitude. Around the mountain, below 1,800 m (2,900 ft), the soil is very fertile so it is intensively cultivated.^[3] This area is also used for grazing of livestock.^[4]

On the lower regions of the mountain, between 2,000 and 2,500 m (6,550-8,200 ft),^[5] the slopes are covered with montane forest. Many species of plant and animal live in this warm moist environment, although the species differ around the mountain with the varying rainfall. The extent of the forest is much greater in the south east, where the rainfall is highest.^[6]

Between 2,500 and 3,000 m (8,200-9850 ft) there is a band of bamboo on all except the northern slopes. Again, the extent of this varies with rainfall, with the south east having far more bamboo than the north west. Few other species live in the bamboo forest, as the dense bamboo suppresses the growth of other plants. Bamboo is unpalatable to most animals, so although they pass through to the moorlands above, few animals live in this zone.^[3][7]

Above the bamboo zone there is a timberline forest zone. This is found between 3,000 and 3,500 m (9,850-11,500 ft). The trees are smaller and more sparse than in the montane forest, and many flowers grow here.^[5][8]

The timberline forest gradually disperses into heathland and chaparrel, between 3,200 and 3,800 m (10,500-12,500 ft). Heathland grows in the wetter areas, towards the east, and is dominated by giant heathers.^[5] In the chaparrel the plants are smaller and shrubbier, and are often aromatic.^[6] The ground in this zone is often waterlogged, although fires are easily started in the dry grasses that are common here. Many animals visit the heathland and chaparrel zone but few live here permanently.

The Afro-alpine zone starts at around 3,800 m (12,500 ft). The plants and animals that live here are adapted to the daily freeze-thaw cycle and are extremely specialised. The Afro-alpine zone can be found right to the peak of the mountain, although it is interspersed with the nival zone above 4,500 m (14,750ft).^[6]

The Nival zone on Mount Kenya is not continuous. It is the area that the glaciers have recently retreated from, where there has not yet been any colonisation by plants. Nothing lives here, although plants begin to colonise rapidly, expanding the Afro-alpine zone.^[6]

[edit] Climate

Main article: Climate of Mount Kenya

[edit] Valleys and Rivers

Further information: River Names on Mount Kenya and Valley Names on Mount Kenya

Mount Kenya is the main water catchment area for two large rivers in Kenya; the Tana, the largest river in Kenya, and the Ewaso Ng'iso North.^[4] The Mount Kenya ecosystem provides water directly for over 2 million people.^[4] The rivers on Mount Kenya have been named after the villages on the slopes of the mountain that they flow close to. The Thuchi River is the district boundary between Meru and Embu. Mount Kenya is a major water tower for the Tana river which in 1988 supplied 80% of Kenya's electricity using a series of seven hydroelectric powerstations and dams.^[9]

The density of streams is very high, especially on the lower slopes which have never been glaciated. The ice cap which use to cover the mountain the the Pliocene eroded large U-shaped valleys which tend to only have one large stream.^[1] Where the original shape of the shield volcano is still preserved, there have been millions of years for streams to erode the hillside. This area is therefore characterised by frequent deep fluvial V-shaped valleys. They occur at a density of around XXX per km.^[10] The gradual transition from glaciated to fluvial valley can be clearly observed.^[11]

Rivers which start on Mount Kenya are the tributaries or two large Kenyan rivers: the Tana and the Ewaso Ng'iro rivers. A lot of Mount Kenyan rivers flow into the Sagana which itself is a tributary of the Tana, which it joins at the Masinga Reservoir. The rivers in the northern part of the mountain, such as the Burguret, Naro Moro, Nanyuki, Liki, Sirimon flow into the Ewaso Ng'iro. The rivers to the south-west, such as the Keringa and Nairobi flow into the Sagana and then into the Tana. The remaining rivers to the south and east, such as the Mutonga, Nithi, Thuchi and Nyamindi flow directly into the Tana.^[10][11]

[edit] Glaciers

Further information: Past glaciations of Mount Kenya

• Only hanging glacier is between Batian and Nelion and feeds the XXX glacier.

The glaciers on Mount Kenya are retreating rapidly. The Mountain Club of Kenya in Nairobi has photographs showing the mountain when it was first climbed in 1899, and again more recently, and the retreat of the glaciers is very evident.^[12] Descriptions of ascents of several of the peaks advise on the use of crampons, but now there is no ice to be found. There is no new snow to be found, even on the Lewis Glacier (the largest of them) in winter, so no new ice will be formed. It is predicted to be less than 30 years before there is no more ice on Mount Kenya.^[13]

The area of glaciers on the mountain was measured in the 1980s, and recorded as about 0.7 km² (0.25 square miles).^[14] This is far smaller than the first observations, made in the 1890s.

Clockwise from the north:

• Northey
• Krapf
• Gregory
• Lewis
• Diamond
• Darwin
• Forel
• Heim
• Tyndall
• Cesar
• Josef

[edit] Rock glaciers

[edit] Periglacial landforms

Although Mount Kenya is on the equator the freezing nightly temperatures result in periglacial landforms. There is permafrost a few centimetres (inches) below the surface.^{[citation needed]} Patterned ground is present at XXXX m to the west of Mugi Hill.^[1] These mounds grow because of the repeated freezing and thawing of the ground drawing in more water. There are blockfields present around 4,000 m where the ground has cracked to form hexagons. Solifluction occurs when the night temperatures freeze the soil before it thaws again in the morning. This daily expansion and contraction of the soil prevents the establishment of vegetation.^[5]

[edit] Soils

Soil types on Mount Kenya roughly correspond with different altitudinal zones. They are broadly classified into four groups: alpine, moorland to bamboo zone, lower slopes and the foothills where the villages surrounding the mountain are. Soils on Mount Kenya are generally very fertile due to their volcanic origin. Some of them have been created by eroding glaciers while others are due to millions of years of fluvial erosion. In all cases they can be mixed with a volcanic ash which increases fertility. Ash and pyroclastic rocks turn into soil faster than volcanic rocks. The soils on the mountain are easily eroded but vegetation including the forest protects it well.^[15] Once exposed the soil quickly erodes down to bedrock,^[15] often by landslides.^[16] Higher on the mountain this is less of a problem as glaciers continuously provide replacement. This replacement is also important as, while the higher soil is fertile, the nutrients are used quickly but also get replaced quickly.^[15]

Removal of plant cover which in turn leads to removal of soil cover is caused by animals including humans. Hyraxes and groove-toothed rats eat considerable vegetation especially when their population is larger than their surroundings can support.^[17] Tourists travelling up and down the mountain erode and widen paths,^[18] and local people living around the forest clear large areas of forest for agriculture. The majority of the forest removal is done illegally.^[16] Once the vegetation is cleared, wind erosion becomes a factor.^[17] The soils are eroded much slower when the vegetation cover is intact by the mass wasting processes of solification and needle ice from freezing at night. Small streams also contribute.^[18]

The highest group, from approximately 4,000m upwards, are influenced by the recent glaciations. Above 4,600m there are loams intermixed with organic material amongst a predominantly scree-clad landscape. Below this, soils from moraines and eroded ridges dominate. These soils have a high organic content and a low bulk density. Valley trains have built up flattening the bottom the the U-shaped valleys. These soils can be of varying depths. Soils in this group are comparable to those found on other high tropical mountains albeit with a higher ash content.^[19] These soils are young, generally less than 10,000 years old, with more being created by the glaciers continuously. As they age they become finer.^[18]

The second group corresponds with the bamboo zone to the moorland zone on the mountain. This was the area once under the icecap at the maximum extent of ice on Mount Kenya.^[1] These soils are also humic and vary in organic content greatly.^[15] To the west there is a maximum in rainfall due to daily anabatic winds.^[20] This has caused the soils in the valleys to be mainly washed away, the remaining humic silt load remaining between boulders at the edge of the valleys. The drainage in the soil varies from moderate to poor. This zone has many parasitic volcanic vents, the soils on which tend to be contain abundant organic matter. This is in contrast to the parasitic craters which contain poorly decomposed organic material.^[19] To the west and south of the mountain, where there is a maximum in rainfall, peat is abundant.^[15]

The third group occurs on the lower slopes between approximately 2,000m and 3,000m where the landscape has never been glaciated.^[15] Almost all of this area is in the forest zone or is cultivated. High in in this zone there is 20-40cm deep band of humic clay forming around the mountain except to the north, where there is moorland instead of forest. Below this, to the north to east to south-west the ground is only partly covered in soil with clays being exposed in many places. In the remaining south-west to west to north there is a dark reddish brown soil which is well drained.^[19] Over all of the lower slopes a dense river network has built up. These rivers are deeply incised, with a dark brown humic loam in the centre with clays exposed on V-valley edges.^[15]

[edit] References

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