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Flashcards in Exploitation of the tundra Deck (20)
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1

What is the tundra?

Northernly ecosystem.
Long and cold winters.
Mean monthly temperatures - -25C.
Stunted trees, mosses and lichens - little moisture due to frozen ground.

2

Who are the Vuntut Gwitchin?

Village of Old Crow - home to 300.
19 villages.
7,500 make up the nation.
Originally lived a nomadic life (constantly travelling) by hunting, trapping and collecting fruits and berries.
Now settled, but still follow the traditional aspects of their culture.

3

What species of animal do the Vuntut Gwitchin use?

Have relied on the caribou to provide them with meat and hides for their clothing and tents.
Bones and antlers can be used for soups and tools.
The muskrat is also trapped.

4

How have the ways of the Vuntut Gwitchin stayed the same?

Still use caribou fences made from wood to hunt the caribou.
The herd are funnelled into the U-shaped trap - huntsmen kill enough to feed the tribe for up to six months.
Still hunt the caribou during their migrations.
Still eat and dry the meat following the traditional methods.
Sustainable way of living.

5

How have the ways of the Vuntut Gwitchin changed?

No longer nomadic – established homes in Old Crow.
Use snowmobiles instead of the old dog sledges as a form of travel.
Rifles are used instead of spears and arrows.
Only take what is needed of the caribou to avoid overhunting.

6

How has the tundra been exploited by outsiders?

Sealing, whaling, trapping for fur.
Mining for gold - led to permanent settlements.

7

What is the land of the Old Crow Flats like?

Yukon territories - Canada.
Ivvavik National Park (Canada) - more measures than ANWR (US side of the border).
Low lying - peat bogs.
Lacustrine - 7m deep.
Soil - 50m deep.
Permafrost.

8

What is the Arctic National Wildlife Refuge (ANWR) used for?

Key caribou calving ground.
Home to 250 animal species.
National resources - petroleum, gas and oil.
Congressional authorisation needed before oil drilling may proceed for designated 1.5m acres.

9

What is the majority of the ANWR used for?

10.1m 'minimal management'.
No roads into the refuge - no spoiling.
Northern edge - Inupiat village of Kaktovik (258 pop).
Southern edge - Gwich'in settlement of Arctic village (152 pop).

10

How has tundra exploitation gotten worse in the last 100 years?

Mining (oil), production of hydroelectric power, fishing and tourism.
WW2 - USA constructed the Alaska Highway - Dawson Creek (Canada) to Fairbanks (Alaska).
To carry weapons.
USSR rise - strategic significance in Alaska.
Military personnel - made up 25% Alaskan population at times.
Roads, airports, early-warning stations built.
BUT military presence = little permanent settlement.
Maintained from the outside - not dependent on local resources.

11

How do harsh cold environments present a challenge for the human development? 8

1. Very low temperatures.
2. Short summers - short growing seasons.
3. Low precipitation.
4. Thin poorly developed soils.
5. Permafrost.
6. Summer surface thaw - waterlogging.
7. Snow lying for long periods.
8. Blizzards.

12

How does the removal of vegetation result in problems in the tundra?

Reduces insulation - deepening the summer active layer.
Vehicle tracks - greatly increase melting as the vegetation is slow to re-establish itself - 50 years.
Buildings - spreads heat into the ground.

13

What is thermokarst, and what is it created by?

A landscape of topographic depressions.
Extensive areas of irregular, hummocky ground, with waterlogged hollows.
Caused by the thawing of ground ice.

14

What damage does thermokarst do?

Ground subsidence.
Tilted/fractured old buildings.
Damage to roads, railways and airfield runways.

15

What are some construction methods used to protect permafrost/prevent subsidence?

1. Elevated smaller buildings - gap allows air to circulate.
2. Large buildings/roads on aggregate pads - layers of 1-2m thick sand and gravel.
3. Utilidors - insulated elevated box - carries water supplies. Heats pipes/sewers between buildings.
Can't be buried underground due to soil damage.

16

What are the human impacts on cold environments?

1. Thermokarst.
2. Hunting - over-exploitation.
3. Transport - spillage risks, vehicles damage soil
4. Tourism - vegetation removal, litter.
5. General air pollution.

17

Why is the tundra considered as a fragile environment?

Climate and limited productivity.
Takes 50 years to regenerate any disrupted vegetation.
Limited diversity - plants are very specialised.
Species have great difficulty in adaptation.
Wide fluctuations within the energy of trophic levels - population numbers rapidly change.
E.g. lemmings/arctic hares - consequences for predators such as arctic foxes/snowy owls.

18

Why was the trans-Alaskan oil pipeline needed?

Designed to carry gas from the north coast of Alska. to the ice free port of Valdez (USA).
Oil removal was a problem - pack ice in the north seas - a tanker couldn't be used.

19

What were the problems faced when developing the trans-Alaskan oil pipeline? 4

1. Environmentalists - tundra should be procted.
2. Concerns over the design, route and ecological impact.
3. Couldn't be buried in the ground - warm oil would melt the permafrost.
4. Concerns of earthquakes, avalanche hazards and animals crossing the pipeline.

20

How was the trans-Alaskan oil pipeline designed? 6

1. Elevated when crossing areas of fine-grained permafrost sediment (1/2 of its length).
2. Shifts sideways - extra protection against damage caused by ground movement.
3. Able to resist being jacked up by years of frost heave.
4. Zigzag pattern - adjust to ground movements e.g. temperature changes or earthquakes.
5. Thick insulation.
6. Refrigeration units - keeps ground frozen in avalanche sensitive areas (6.5km covered).
- some permafrost-free areas are also crossed.