Limiting Factors

Source:  Limiting Factors    Tag:  arctic fox physical characteristics
Density Dependent Factors: Density Dependent factors are characteristics that are influenced by the size of a population. Density-dependence generally regulates populations within ecosystems that have many species, if they are not stressed by physical conditions. This is not typically true of the tundra. Its extreme climate reduces the number of species that successfully survive there. Even though this is true, species are still affected by predation and competition in the Tundra. Musk Oxen and Caribou can compete for sedges and grasses. Also, when the population of arctic hares increases the population of artic foxes will go up due to increases predation.
Density Independent Factors: Density Independent Factors affect populations by the same percentage, regardless of density.Temperature is a major factor in the Tundra because most species aren't able to tolerate the cold temperature and harsh winds. Trees and other tall plants cannot survive in the Tundra. Another density independent factor is the amount of sunlight. Depending on the latitude, the Sun can remain below the horizon for up to 2 months, leaving the Arctic tundra in darkness. Although the sun remains in the sky 24 hours a day during the summer, it stays close to the horizon and provides only low intensity sunlight. This is another reason why trees cannot survive in the tundra; they require an ample amount of sunlight.