Effects of degradation on the tundra landscape
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 employmentWhen people are paid to work. in new industries, which provides them with money to improve their standard of livingThe amount of wealth or personal comfort that a person or group of people have., but, changes their traditional lifestyleThe behaviour, habits, ideas and customs that are typical of a particular society..
- entertainmentsFacilities that are built for people to use in their free time e.g. cinemas. and modern 'Western' facilities are influencing the traditional lifestyle of Inuit hunters.
- pesticideA chemical used to kill pests, such as the potato cyst nematode which is a pest that destroys potato crops. 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 adaptationA feature of an organism's body which helps it to survive. to survive in the harsh climate - but the smallest pressures can bring about their destruction.
- polar ice capsA large area of land covered in ice. are melting because of an increase in global warmingThe rise in the average temperature of the Earth's surface. .
- 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 PipelineA very long pipe that transports oil across Alaska. was built on a caribou migration routeThe usual path that reindeer take when they are moving into the Tundra in summer or out of the Tundra in winter.. 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 birdsBirds which fly in and out of an area depending on the time of year. 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 minesAn area where the natural resource nickel is extracted from the ground. in Russia is so polluted that the plants in the area have died.
- Footprints and tyre tracksThe marks left in the land by vehicles driving over it. can be seen for many years after they were made. When the Sun hits the ruts it causes the permafrost to melt; this causes erosionThe wearing away of pieces of rock, soil or other solid materials. and the ruts get bigger, and eventually the ruts turn into gulliesA small valley or ravine worn into the landscape..
The tundra is one of Earth's three major carbon dioxide sinkA place that absorbs a lot of the gas carbon dioxide.. A carbon dioxide sink is a biomassThe number of living things in a given area. (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 gasThe gases responsible for global warming - carbon dioxide, methane, nitrous oxide and CFCs (chlorofluorocarbons). that contributes to global warming. Plants normally release carbon dioxideA gaseous compound of carbon and oxygen, which is a by-product of respiration, and which is needed by plants for photosynthesis. after they die and decayWhen plants wither and die.. However, in the tundra, plants cannot decomposeIf a substance decomposes, it breaks down into simpler compounds or elements. 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 atmosphereThe layers of gases that surround the Earth. The important gases in the atmosphere are nitrogen, oxygen and carbon dioxide.. 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 sourceAny process that releases carbon into the atmosphere. and not a carbon sink.
