Natural regionsEffects of degradation on people and environment

People

• Illegal hunting and fishing is threatening the traditional way of life for the Inuit hunters as their food sources come under threat.
• Local people have found employment in new industries, which provides them with money to improve their standard of living, but, changes their traditional lifestyle.
• Entertainments and modern 'Western' facilities are influencing the traditional lifestyle of Inuit hunters.
• Pesticides present in the food chain are harmful as local people hunt food for survival.

Environment

• The tundra is a very fragile environment. The plants and animals that have made it their home have made some incredible adaptations to survive in the harsh climate - but the smallest pressures can bring about their destruction.
• Polar ice caps are melting because of an increase in global warming.

• Many polar bears have starved to death as their feeding patterns have been disrupted.

• Melting ice caps are causing sea levels to rise and low-lying coastal areas to flood.
• Animals are often shot or scared away when they try to move through a town.
• The Trans-Alaskan oil pipeline was built on a caribou migration route. In some areas, the pipeline was raised above the ground to allow the caribou to pass under it.
• Burst pipes have spilt hundreds of thousands of gallons of crude oil in Alaska devastating this fragile environment.
• Oil spills have caused serious water pollution in the Arctic Ocean.

• Some animals' movements to traditional feeding and nesting grounds have been disrupted by obstacles, eg pipelines above the ground.
• Pesticides have been used to control the masses of insects. This is a problem as thousands of migrating birds feed on the insects and are subsequently poisoned or die due to their food source being removed.
• Any damage to the tundra landscape is slow to recover. The short growing season means that bulldozer tracks from the oil and natural gas industries could take centuries to restore.
• Pollution from mining and oil drilling has contaminated the air, lakes and rivers. The land around some nickel mines in Russia is so polluted that the plants in the area have died.
• Footprints and tyre tracks can be seen for many years after they were made. When the Sun hits the ruts it causes the permafrost to melt; this causes erosion and the ruts get bigger, and eventually the ruts turn into gullies.

The tundra is one of Earth's three major carbon dioxide sinks. A carbon dioxide sink is a biomass (biological material from living, or recently living organisms) which takes in more carbon dioxide than it releases.

This is very important because carbon dioxide is a greenhouse gas that contributes to global warming. Plants normally release carbon dioxide after they die and decay. However, in the tundra, plants cannot decompose because of the cold, harsh climate.

The remains of plants which are thousands of years old have been found in the permafrost. In this way the tundra traps the carbon dioxide and removes it from the atmosphere. Unfortunately, global warming is melting the permafrost and now, every year, several metres of tundra is disappearing.

As the tundra melts, the plant matter decomposes and returns carbon dioxide to the atmosphere, increasing global warming. As a result, Alaska is now considered a carbon source and not a carbon sink.