how do physical factors affect the nature of the soils and nutirent cycling in the tundra?

Question 1

frost heve

Answer 1

process where water freezes in the soil and pushes the surface upwards and churns it

Question 2

solifluction

Answer 2

literally means flowing soil and is an accelerated form of soil creep. winter=water freezes in soil +expands +segregation of individual particles. spring=ice melts and water flows downhill, cannot infiltrate soil due to permafrost

Question 3

how does frost heve and mass movement (e.g avalanches) affect vegetation?

Answer 3

makes it difficult for roots to get fresh water. movement of active layer makes it hard for roots to develop. avalanches wipe/clear away vegetation and animals

Question 4

soils

Answer 4

affected by permafrost and low temps. bacterial activity is low and waterlogging can sometimes lead to formation of acidic humus. blue/grey blotchy mud found due to waterlogging (gleying) as less oxygen. soil contains angular fragments due to freeze thaw and frost heave. podzols may develop in better drained sites

Question 5

nutrient cycling

Answer 5

essential as plant growth is limited because rate of weathering is slow. precipitation levels are low=few nutrients dissolved in rainfall. frozen ground and/or snow cover makes it difficult for the plants to root and reach/absorb limited supply of nutrients.