P8 Flashcards
(33 cards)
The value of wilderness
- A contrast has to be drawn between active glacial and periglacial landscapes found in high (polar) latitudes and high altitudes, and relict glaciated landscapes.
- Whereas nearly all of the former can be classified as true wilderness as they are remote, possess a harsh physical environment and carry little or no population, except for small groups of indigenous people or groups exploiting their resources short term, the latter relict areas are often more densely populated as they provide many more opportunities for economic development and employment, for example farming, forestry and tourism.
- It is precisely the qualities of wilderness which provide opportunities for spiritual refreshment and enjoyment for many travellers and explorers who wish to experience pristine, almost wholly natural environments and almost always untouched by humans.
- Wildernesses have inspired an enormous range of people to write, paint and communicate their feelings and experiences - for instance wilderness poets such as Robert W Service from Alaska, polar explorer John Muir or legendary broadcaster and naturalist David Attenborough.
- the concept of the wilderness continuum and shows how high-quality wildernesses such as Antarctica or the Arctic, both barely modified by human activity, contrast with lower wilderness quality areas, which merge into quite heavily settled rural areas.
- For example, the relict environments of the summits of Snowdon or the Cairngorms, both reached by mountain railways, only have elements of pristine quality; they have lost their innate remoteness to large quantities of tourists.
Environmentalists and ecologists would point to wilderness areas, such as the polar environments, being of inherent value for scientific reasons. They argue that areas of a truly pristine nature are very useful for research for a number of reasons:
• the need to maintain a gene pool of wild organisms to ensure the maintenance of genetic variety (global seed bank in Svalbard)
• the need to retain wilderness so that animal communities can remain in their natural environment, for example providing sanctuary for the migratory bird and animal communities of the Alaskan North Slope
• to use wholly natural communities that still exist as control systems for comparison with exploited, mismanaged systems elsewhere.
Scientific research
Both Arctic and Antarctic polar environments have become ‘living labs’ for scientists. They have both similarities and significant differences in their research programmes.
Economic value of glacial environments
- Millions of people, who live far from any mountains, benefit from a range of goods and services provided by glacial environments, both relict and active.
- These include supplies of pure mountain water, timber (usually coniferous woodland), hydroelectric power for their homes, as well as the opportunity to enjoy beautiful mountain environments such as the Alps or Himalayas for recreation and leisure.
- About 8% of the world’s people live in polar and mountainous and upland regions, many of which have been glaciated in the past or still contain some glaciers, albeit mostly diminishing in volume.
Farming
- Within mountainous regions in developing nations, there may be limited transport links and access to essential supplies and markets may be poor; employment opportunities are also limited.
- In countries such as Nepal, Bolivia (Altiplano), Ethiopia (Bale Mountains), the highlands are largely inhabited by indigenous communities who gain their living from subsistence farming.
- In Bolivia 70 per cent of the population lives in the High Andes, growing crops such as potatoes, quinoa and beans to feed themselves, as well as rearing lamas and alpacas, yet they earn only 30 per cent of the country’s GDP.
- Almost all of the 60 per cent of Bolivia’s population living below the poverty line are indigenous Indians living in the Altiplano of the High Andes.
- The development of internet and mobile phones, leap frogging old technology of landlines and cables, has revolutionised their lives, providing many opportunities for cottage industries such as weaving and knitting co-operatives, and ecotourism.
- In Alpine areas in developed countries, the agriculture in upland glaciated regions is primarily pastoral because of the above-average precipitation, rugged terrain with steep slopes and stony, shallow soils, which together make cultivation difficult.
- In the truly Alpine areas transhumance is a traditional pattern of livestock management; the farming system takes advantage of the seasonal climate cycle - in summer animals are grazed at high altitudes on Alpine meadows, which become free from snow and provide high-quality grass (the summer settlements are known as sacters) - at the same time the grass in the valley bottom can be made into hay for winter feed.
- In the snowy winters the animals are brought down and housed near the farm houses and are fed on hay or graze the lower pastures.
Silviculture:
The planting of trees for commercial forestry.
Antarctica
- Antarctica was designated a continent of peace and science as a result of the 1959 Antarctic Treaty and subsequent protocols.
- In the International Polar Year of
2007-09, the United Nations Environment Programme reports that 60 countries and more than 10,000 researchers took part in scientific research there costing over $1.5 billion.
Some of the planned or ongoing research programmes being carried out by international Antarctic scientists include:
* understanding global change - past, present and future - by looking at ice cores
* researching life on the edge’ to explore how ecosystems cope with intensely harsh conditions
* investigating subglacial Lake Vostock and other lakes beneath the ice sheet
* developing sustainable food webs in the Southern Ocean ecosystem; in particular, looking at changing impacts on the various trophic levels such as the decline in krill, a key component of the Antarctic marine food web
* studying the Earth’s upper atmosphere and its links to the lower atmosphere and the Earth’s climate - taking advantage of the unpolluted atmosphere above the continent
understanding how the Antarctic ice is melting, in terms of scale and pace, using satellites and field data.
Forestry (silviculture)
- Depending on farm prices and the degree of government support systems (such as EU rural payments), hill farming is an increasing struggle in many regions and uplands are now increasingly used for forestry (silviculture).
- In the UK this is carried out by the Forestry Commission and private investors, with the main type of tree being non-native, quick growing conifers, such as Sitka spruce, grown for softwood timber, wood pulp and even paper.
- Conifers tolerate harsh climates and acidic soils that would not be suitable for other land uses.
Mining and quarrying
- Glacial erosion plays an important role in removing regolith (loose overlying soil) and vegetation to expose economically valuable rocks.
- In many active or relict areas there are mines and quarries of mineral deposits and ores, as well as rocks such as slates as many of the glaciated mountains are made from igneous and metamorphic rocks.
- In lowland areas, outwash deposits from the Pleistocene Ice Sheets provide a very important source of sand and gravel for the building industry, pre-sorted by meltwater into sands and gravels to be sold as aggregates, making them very useful for making concrete.
Hydroelectricity
- Hydroelectric power (HEP) is a major use of water derived from glaciers.
- Both Norway and New Zealand derive over 90 per cent of their electricity from this source.
- In most cases either a natural ribbon lake or a dam and reservoir in a glaciated valley provide the HEP.
- Switzerland has over 500 HEP stations, producing some 70 per cent of its electricity.
- Clearly HEP is a renewable ‘green’ source, although there are issues with both the reliability of water supply and environmental concerns over damming of rivers.
- In mountain settlements in developing nations, such as Nepal or Bolivia, micro-hydros can revolutionise the quality of life in many villages.
Tourism
- The tourism industry has seen tremendous growth in recent decades, which has brought many economic benefits to mountain regions, with visitors attracted to the spectacular scenery of both present-day and relict glaciated landscapes.
- A huge range of year-round, outdoor activities are possible in Alpine landscapes - hill walking, climbing, mountaineering and skiing - which has led to whole regions capitalising on their tourist potential.
- Glaciated regions are increasingly visited for the glaciers themselves, which puts pressure on some very fragile landscapes.
- some of the developing areas for glacial tourism - note that it is a worldwide activity.
- This table demonstrates how long-haul travel and modern communications has brought mass tourism not only to traditional areas, such as the Swiss Alps and the Rockies, but also to remote polar regions in the Arctic (Alaska, Greenland, Iceland and Svalbard) and Antarctic (South Georgia and the Antarctic peninsula).
- These areas have become increasingly popular, especially for expedition ship cruising, which has all sorts of implications for their environments.
- The economic value of any mountain tourism requires careful management of the benefits so that these are not outweighed by environmental costs to the scenery and to the culture of the local people.
- It’s a very fine balance.
- So much depends on the fragility of the landscape and the nature and intensity of the economic activities.
The increase in damage from ski resorts as a result of climate warming
1 Skiers will be forced to high altitude resorts as lower resorts lose snow cover. This may increase the environmental pressures on a smaller number of higher resorts.
2 Removal of vegetation for chair lifts and gondolas may lead to an increase in erosion and increase the risk of avalanches.
3 Snow cover on middle and lower slopes is less certain - many banks are now cutting off funding for the lower resorts, which may face economic ruin.
4 More gondolas and chair lists will be needed to take skiers from the lower resorts to upper slopes, e.g. at Mayrhofen, Austria, where gondolas capable of holding 160 take people to the higher slopes.
5 Resorts in the lower parts of the valleys could face economic ruin if they cannot
a) produce more snow or
b) get skiers to upper slopes.
6 Increased usage of environmentally damaging artificial snow.
Developing areas for glacial tourism
Developing areas for glacial tourism
Developing areas for glacial tourism
Ecological and environmental value
- Both glacial landscapes and periglacial landscapes make a very significant contribution to the world’s life support systems.
- Approximately 75 per cent of all the freshwater of the world is locked up in ice - so glaciers contain nearly two per cent of all water overall.
- Glacially eroded valleys in many mountainous regions form natural hollows for water collection, forming ribbon lakes, or can be dammed for reservoirs, for example in the English Lake District.
- Glaciers are especially valuable as a source of water for irrigation as they produce most water in late spring and summer, which is often the hot, dry season when other sources dry up.
- For example, in the USA the Arapaho Glacier currently produces about 260 million gallons of drinking water per year for the city of Boulder, Colorado, as well as irrigating huge areas of crops such as fruit and grapes.
- Glaciers have a very cool and beautiful image and this is used to promote sales of bottled water.
- Being composed of freshwater, icebergs also offer a potential water resource, but there are numerous complications even in their potential use.
- The extensive areas of permafrost and tundra peat are major areas for soil carbon storage.
- Currently the Arctic lands remain a weak carbon sink, meaning that more carbon is added each year than is lost.
- However, as permafrost melts as a result of positive feedback within the climate warming process, ancient carbon is being released, especially via methane emissions, thus upsetting the balance in the system.
- Tundra vegetation occurs in periglacial areas that are not ice covered at present, both in high latitudes (Arctic ecosystems) and high altitude (alpine ecosystems), covering around 8 million km? of the Earth’s surface.
- The presence of permafrost in most areas in the soil increases their fragility.
- In the lower Arctic latitudes (around 70 to 75 °N) there is a continuous cover of ground vegetation, with sedges and mosses in the wetter hollows and scattered dwarf trees (elder and birches) on the lower ridges.
- Elsewhere heaths, grasses and rapidly flowering plants flourish.
- At higher latitudes (75 to 80 °N) and higher altitudes, polar desert conditions prevail, but a small range of plants survive in favourable sheltered locations such as the purple saxifrage and arctic poppy.
- Tundra plants have to adapt to low temperatures, drying winds and snow blasts in winter blizzards.
- The system has low biodiversity because of low primary productivity and the low nutrient content of the Arctic soils, leading to very weak nutrient cycling in dynamic equilibrium with the underlying permafrost, so any melting will have dramatic effects.
- Human activities can have dramatic impacts, both directly, such as vegetation being removed during the building of roads and infrastructure, and indirectly through pollution.
- Toxic chemicals/acid rain from coal mines (Svalbard) and metal smelting in the Kola Peninsula (Russia) lead to the contamination and melting of the permafrost and the formation of thermokarst conditions.
- A growing threat is the potential for oil spills as Arctic oilfields are developed on the Alaskan North Slope and Russian Siberia, controversially in areas of outstanding ecological value, such as the Arctic National Wildlife Refuge (ANWR) where permission has just been given to drill (2015) amid huge controversy as it affects the lives of the native peoples as well as the environment and ecology.
- In 2005 the Millennium Ecosystems Assessment (MEA) identified the value of polar ecosystems and posed questions about what humans would lose if they were irreparably degraded.
Table 7.2 summarises the value of these ecosystems
using the MEA framework
Carbon sink:
A natural or artificial reservoir that absorbs more carbon than it releases, leading to carbon accumulation.
Biodiversity:
A measure of the variety of organisms present at a particular location.
Primary productivity:
The rate at which energy is converted by photosynthesis; it has a major influence on the level of biodiversity.
Value of polar ecosystems
Natural hazards in glacial environments - rising risks
- Both current glaciated and relict upland regions are hazardous because of the high incidence of avalanches, rock falls, debris slides and flooding.
- These hazards have the capacity to develop into disasters because of the rising human vulnerability in these areas, resulting from increasing population and development as well as the growing popularity of outdoor sports and adventure tourism, which put more people at risk.
Avalanches
An avalanche risk exists when shear stress exceeds shear strength of a mass of snow located on a slope. The shear strength of a snow pack is related to its density and temperature.
Snow avalanches result from two different types of snow pack failure:
• loose snow
slab avalanches
Snow avalanches result from two different types of snow pack failure:
• loose snow acts rather like dry sand; a small amount of snow slips out of place and starts to move down slope
• slab avalanches occur when a strongly cohesive layer of snow breaks away from a weaker underlying layer. A run of higher temperatures followed by refreezing creates ice crusts, which provide a source of instability. Slabs can be as large as 100,000 m’ and can bring down 100 times the initial volume of snow and cause huge danger.
Most avalanches start off with a gliding motion then rapidly accelerate, especially on steep slopes in excess of 30º. Three types of avalanche motion commonly occur:
• powder avalanches (the most hazardous)
• dry flow avalanches
• wet flow avalanches, which occur mainly in spring While avalanches tend to follow well-known tracks and can often be predicted, they are nevertheless a significant hazard, usually killing around 200 people per year with most of these deaths in the Alps or the Rockies.
Figure 7.5 shows there is a large variety of ways by which avalanche hazards could be reduced.
In 1970 the Peruvian towns of Yungay and Ranrahirea were destroyed by an earthquake-induced ice and rock avalanche from Mount Huascarán. It travelled 16 km down valley as a muddy flood, killing over 18,000 people. The 2015 Nepalese earthquake set off many ice and rock avalanches that killed some members of expeditions at Everest Base Camp.
