Cold Environments

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  • Created on: 27-04-13 17:14

Features resulting from glacial deposition

Ice can transport materials ranging in size and can be carried within the ice on the ice or at the base of the ice

Erratics - they are large boulders foreign to local geology that have been dumbed by the ice. They can be left stranded and in odd positions 

Till- is a glacial deposit made up of rock flour (sands and clays) mixed with rocks of differrent sizes - it has two types , one is lodgement which is droppred by an activley moving glacier or ablation which is till dropped by stagnant ice

Moraines- loose fragments of rock which have been weathered from the valley sides and have fallen downslope onto the ice. Lines of rock on valley sides is lateral moraine , when meet they form medial moraine at the centre. Moraine dropped at snout of glacier is called terminal moraine- characteristics depend on amount of material carries by ice , rate of ablation and ice movement 

Drumlins - till been deposited in a oval mound, consist of sandy till. Steepeer end facing the direction the ice came from- deposited where friction between the ice and the rock flour was stronger friction between till & the ice

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Fluvioglacial Deposits

Prolonged Drift - material dropped in glacial lakes , along lake shorelines. In the lakes material was deposites brought down by seasonal meltwater . Summer deposition is indicated by a layer of coarse deposits (coareser , heavier material) , winter deposition indicated by a thin layer of material as there was less meltwater. 

Ice contact stratified drift - consits of strafied sand and gravel that is sorted by the action of meltwater streams and are seposited next to the glacier - often modified due to ice retreat:

  • Eskers - ridges of coarse fluvioglacial material (sands and gravels)- theory they were formed by material was deposited in sub-glacial meltwater tunnels during a period of lengthy ice stagnation 
  • Kames- irregular mounds of bedded sands and gravels formed when a meltwater stream flowed out beneath an area of stagnant ice into a lake dammed between the ice front and drift material (terminal moraine). have small shallow hollows due to deposition of material around blocks off ice broken off from the front of stagnat ice. Each block of ic finally melts leaving a whole
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Periglacial Features

Patterned Ground -ranges in size and shapes can be striped (slopes) , circles and ploygons (flat ground). Frost heaving causes it , it moves large stones to the surface , stones form the edges of the pattern.  Intense cold causes ground to crack and stons may roll into cracks

Pingos - isolated hills upto 100m in height and 1km diameter  they form due to movement and freezing of water under pressure - there are open-system and closed-system pingos.  

  • Open system pingos form when source of water is from distant and elevated source - fond where there is discontinous pemafrost , groundwater forces its way to the surface and freezes - high hydrostatic pressure
  • Closed system pingos -  isolated features on flat surfcaes and in areas of continous permafrost , are formed when a lake is filled with sediment , it causes an increase in amount of insulation and permafrost expands. Then traps of body of water which freezes and expands 

Ice wedge - mass of ice in ground when ground freezes cracks develop in the ground - in summer water flows into cracks freezes in low temps and enlarges crack can get 10m- 30m deep

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Relict (past) features

Dry Valleys- river valleys without rivers , during pereglacial period limestone and chalk became impermable to permafrost so rivers flowed over surfaces. End of periglacial period normal permeabily returns and water sink into the permeable rocks and valleys left to dry

Misfit Rivers - are rivers or streams that occupy large valleys. During pereglacial period rapid run-off from snow melt would have allowd these rivers to carve steep and deep valleys and now small rivers and strems flow in them

Scree Slopes - slopes with large quantities of angular rock - angl of rest where the slope is stable and no further mass movements occur

Loses - deposit laid down by the wind & consists of unstratified and structerless silt but also angular and sub-angular pieces

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Vegetation/Animals in Cold Environments

Vegetation- towards the poles climate becomes drier and cooler and summers are shorter , and plant cover is reduced. Polar have little vegetation less than 10%. In many places such as Antartica there is little nutrents in the soil and very limited lichen & moss

  • Low Artic Tundra consists of dwarf shrubs,mosses, gross and lichen
  • High Artic Tundra contains lower order species such as herbs and moss (areas contain bare rock rather than vegetation)

Productivity of cold environments is low affecting vegetaion growth is slope angle , local climate & moisture avalibility. Some plants are adapted such as cushion plants which are close to the ground surface so that it reduces the impact of windspeed on water loss. Herbaceous perenials commons are large underground root structure to store food over winter.

Animals - there are very few species (70 breeds in Artic), and are large species for example caribou and lemmings . Many animals genetically unique due to variations such as climatic variations. Many have adaptations such as high-quality fur insulation, increase metabolic rates and large litter sizes. 

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Soils and nutrient cycles

Soil - strongly affected by permafrost and low temperatures. Bacterial activity is low and waterlogging leads to the formation of acid humus. Below surface blue-grey blotchy mud is found due to waterlogging (gleying). Ferric compounds are turned into ferrous compounds as oxygen us reduced in the soil leading to blue-grey blotches. The soil contains angular fragments due to freeze-thaw weathering. Most common soil found in tundra are known as tundra greys. On the better drained sites podzols may develop- it is ligth coloured soil found under confinerous forests or moorlands where rainfall exceeds evaportaion. The constant downward movementof water leaches nutrients from the upper layers , making podzols poor agrcultural soils 

Nutrirent Cycle - The amount of nutrients in a soil are limited because the rate of weathering is slow. Also as precipitation levels are also low there are few nutrients dissolved in rainfall. Frozen ground and snow can make it difficult for the plant roots to reach and absorb the limited supply of nutrients

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Human Impact on the Envrionment

Disturbance to flora and fauna as well as permaforst cause concern. Ice-rich permafrost can be destroyed by heat from buildings , pipelines , changes in vegetation cover and impact of vehicles. Thermokarst refers to the subsidence that occurs as permafrost melts , the most common cause of man-induced thermokrast on a landscape is the clearance of the surface vegetation for agriculture or construction purposes and vehicles( especially in summer when surface has thawed amd is soft and wet, surface vegetation can be destroyed)- Factors that control thermokarst: 

  • ice content on underlying permafrost and the presence or absence of excess ice
  • thickness and insulating qualities of the surface vegetation 
  • duration and warmth of summer period 
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Resource Exploitation

Agriculture - one of the main resources of cold environments is pasture land. Farming is limited due to the extreme climate as there is a short growing season , which lasts just 90 days (150-220 normally), one degree celsiuis decline from annual average temp. will reduce crop yields by 15%. Soils are poor quality with myuch gleyed soils (will respond well to fertilisers). However in Artic there are large amounts of cheap geothermal energy which has allowed for cultivation in greenhouses. Grazing land is important for production of winter feed such as hay and silage. Main crops grown include potatoes , barley & oats - makority grown for local consumption . However majority of pasture land has been affected by contamination e.g military activity or nuclear testing in the Artic. - contaminates moss eaten by caribou then eaten by people. There are other problems which include conflicts between indeginous herders and other land users. As in Sweeden the indeginous reindeer herders the Sami say their traditional way of life is in jeopardy because they owners of the private forests are using the law to exclude them from woodland. For the Sami , herding reindeer is a way of life , the reindeers seek refuge from the bitter cold winter winds in the forests however much of forests is private , and they are disputing the Samis rigth to be there. 

Energy & Mineral Extraction - Basic approaches to building a pipeline on permafrost: 

  • bury the pipline in a trench 
  • suspend the pipeline above ground on trestles 

Howvever the pipeline due to the heated oil it carries can thaw the permafrost- so susopended above ground - but extreme temperatures make pumping hard . Pollution is also a major problem as oil breaks down more slowly under cold and dark conditions . Oil leaks cause destruction of Vegetaion , decreased fish stocks and reduced caribou

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CASE STUDY : OIL EXPLORATION SIBERIA

Siberia has huge reserves of oil and gas , which provides great econmic oppurtunity - been exploited in the area since the 1970s 

Environmental Impacts ; 

  • pollution of physical environment 
  • disruption of natural proccesses through infrastructure development - habitats 
  • soil pollution - broken pipelines

Economic and socio-political impacts ; 

  • population redistrubution - Khanty population off their hunting territories
  • economic dependency - oil companies produce new technologies such as snow-mobiles which Khanty have become dependent on 
  • detiorating physical & mental health - depression and alcoholism due to loss of traditional way of life & lack of employment

Cultural Impacts

  • the destruction of native religion including scared places and culturally signifcant animal species 
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CASE STUDY : Ski tourism in Europe

Most European tourism is in the Alps , recieves 100 million tourists each year- in some places 80% of jobs depend on tourism , however there are environmental issues:

  • construction of ski pistes , acces road , parking , cafes - removes habitats
  • removes natuarl protection against avalanches 
  • exhaust fumes lead to further forest damage and air pollution (travel by car/plane)
  • skiers damage trees by knocking off branches 
  • litter is a problem - orange peel takes 2 years to break down 
  • ski runs/lifts leads to forest clearance - increase in avalanches - 100km2 in alps 
  • new resort construction - buldozing / blasting/re-shaping makes slope weaker - more chance of avalanches 
  • water pollution and sewage disposal 
  • large accomadation blocks - visual pollution 
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CASE STUDY : sustainable development in the Alps

Environmental Management 

  • Matterhorn Ski region - electrically powered buses serve all 3 resort stations 
  • 313km of marked pistes in Zermatt - cog-railway , 9 cable cars , 5 gondola lifts , 8 chair lifts 
  • Zermatt Mountain Cableways- a work party composed of environmental and planning firms to work out an overall plan 'Sustainable skiing areas around Zermatt'- highlight areas of conflict between nature & construction
  • due to dramatic development there was much waste ZMC- old ski lifts , pylons were recovered- e.g.Blattenlift was restored by landscaping and reseeding - area looking more natural

Protection of forests and wild game 

  • ZMC , game keepers, forest wardens , biologists drew up a forest and wild game protection programme with the aim to improve conditions for forest and wild game in the winter - conservation areas have been marked off and marked with notices . Specially constructed game observation points watch animals without disturbing them- Information camapign so local peopel and visitors sensitive to wildlife protection 

Restoring Nature 

  • Gant region 2005- returning old ski routes to their natural state - tidying up natural landscape-facilites unus
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CASE STUDY : sustainable development in the Alps

Replanting 

  • provide erosion protection and reduce damage on landscape 
  • planting where gaps in vegetation and areas at risk of erosion - stabalise slopes

Environmental monitoring of building works

  • building work monitored by scientifically trained specialist
  • aim to work with consideration and long-term sustainability 

Environmental Education 

  • ZMC - placing increasin emphasis on communicating ecological interelationships 
  • information boards placed about Schwarzsee Nature Conservation Areea 
  • glacier path opened in Gant-Findel - near mouth of glacier 
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CASE STUDY : Managing Antartica

Short Term Gains - so far continent has remained relativley unexploited  and short term gains such as mining for natural reaource have been RESISTED. It is the worlds largest wilderness almost entirley buried by snow and ice , it has no pernament inhabitants apart from 1000 scirntists. It covers an area of 14million km 3 (Europe). 99% of continent is covered by ice - however temps have risen by 2.5 degrees since 1940's 

Sustainable Management 

  • Artic Treaty 1961 - for peaceful purposes only and environment protected
  • 46 countries signed Treaty - 80% of worlds population 
  • Artic Treaty includes - all ships and aircraft operating in Anatarica have to be inspected, Nuclear explosions and radioactive waste are prohibited , military action in Antartica are prohibited , 5m in animal - not touch or feed , no litter , no ships bigger than 500 passengers 
  • There are minerals in Anatrica - not in big quantities, technical economical and environmetal difficulties of extracting minerals is immense
  • Treaty shows international co-operation and an sustainable policy 
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CASE STUDY : Managing Antartica

Environmental Impact Assesment (EIA)- NO activity within Antartica may proceed unless there is sufficent information to determine the environmental impact is acceptable- strict regulations on waste and oil discharged in to the sea , chemical and garbage from ship is prohibited

Tourism in Antartica 

  • There were more than 37,000 tourist in 2006 - 14% increase from 2005
  • Concern of wilderness while giving people best oppurtunities to experience 
  • Cruises, sail yachts , climb mountains use the services of only land based tour company Adventure Network International - one vessel at a time on a landing site and no more than 500 passengers 
  • with careful management fragile environment relativley unexploited- global warming has a negative effect- tourism growing 
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CASE STUDY : Climate and eco-system in Alps

Switzerland - temps in summer up to 25 degrees , winter temps 2 degrees in valley but at higher altidudes below freezing. Rainfall varies throughout country 530mm-25000mm.

Alpine vegetation (adaptations) : 

  • brigth pigments protect from ultra - violet radiation 
  • colour attracts insects for pollination 
  • growing close to rocks to avoid trampling - orchids
  • hairs on leaves reduce moisture loss
  • waxy coating to reduce water loss
  • growing close to ground reduces moisture loss - lower wind speeds at ground

800m coniferous trees replace deciduous trees as they are adapted to photosynthesise at lower temps- decidous trees shed leaves at low temps- red spruce typically found - 2000m tall trees are replaced by bushes and shrubs - Forests being affected by acid rain and pollution  , they die , higher risk of avalanches , less vegetation to bind soil and less interception 

Animal life - is under threat from increased human activity especially tourism development- typical species include ibez (mountain goat) , the chamois (antelope). Characteristic birds include the chough and golden eagle - over 80 species threatened by extinction 

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CASE STUDY : Climate and eco-system in Alps

Switzerland - temps in summer up to 25 degrees , winter temps 2 degrees in valley but at higher altidudes below freezing. Rainfall varies throughout country 530mm-25000mm.

Alpine vegetation (adaptations) : 

  • brigth pigments protect from ultra - violet radiation 
  • colour attracts insects for pollination 
  • growing close to rocks to avoid trampling - orchids
  • hairs on leaves reduce moisture loss
  • waxy coating to reduce water loss
  • growing close to ground reduces moisture loss - lower wind speeds at ground

800m coniferous trees replace deciduous trees as they are adapted to photosynthesise at lower temps- decidous trees shed leaves at low temps- red spruce typically found - 2000m tall trees are replaced by bushes and shrubs - Forests being affected by acid rain and pollution  , they die , higher risk of avalanches , less vegetation to bind soil and less interception 

Animal life - is under threat from increased human activity especially tourism development- typical species include ibez (mountain goat) , the chamois (antelope). Characteristic birds include the chough and golden eagle - over 80 species threatened by extinction 

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CASE STUDY : Climate and eco-system in Alps

Switzerland - temps in summer up to 25 degrees , winter temps 2 degrees in valley but at higher altidudes below freezing. Rainfall varies throughout country 530mm-25000mm.

Alpine vegetation (adaptations) : 

  • brigth pigments protect from ultra - violet radiation 
  • colour attracts insects for pollination 
  • growing close to rocks to avoid trampling - orchids
  • hairs on leaves reduce moisture loss
  • waxy coating to reduce water loss
  • growing close to ground reduces moisture loss - lower wind speeds at ground

800m coniferous trees replace deciduous trees as they are adapted to photosynthesise at lower temps- decidous trees shed leaves at low temps- red spruce typically found - 2000m tall trees are replaced by bushes and shrubs - Forests being affected by acid rain and pollution  , they die , higher risk of avalanches , less vegetation to bind soil and less interception 

Animal life - is under threat from increased human activity especially tourism development- typical species include ibez (mountain goat) , the chamois (antelope). Characteristic birds include the chough and golden eagle - over 80 species threatened by extinction 

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