Soils

Question 1

GLEY soil forming factors

Answer 1

v- plant roots do not penetrate deeply, resulting in limited recycling of minerals due to vegetation.

C- low temperatures lead to slow rate of decomposition of organic material/matter creating a thin humus layer

R-found on flat surfaces such as plateau moorland or foot of slopes means water cannot drain away/waterlogging in summer

O-anaerobic conditions means few organisms living in soil to burrow/tunnle through it. Soil has a blue grey colour due to anaerobic conditions the iron compounds are changed from red brown to blue grey.

P-impereable clay impedes drainage and causes waterlogging

D- red mottling in small air pockets due to re-oxygenation of the iron in soil due to burrowing/drying

Question 2

BROWN EARTH soil forming factors

Answer 2

V- vegetation is deciduous woodland with abundant leaf litter and thick humus layer which produce mull/less acidic humus

O- high levels of biota/bacterial activity. The soil is well mixed therefore horizons are not clearly defined

R- forms on gently sloping and low lands

P- C horizon (pm) is generally weathered rock

Question 3

PODZOL soil forming factors

Answer 3

V- coniferous needles and cones produce acidic (mor) humus. Shallow roots mean limited absorption of deep leached minerals, shallow roots also leads to limited nutrient recycling

C- low temperatures lead to slow decomposition. High precipitation leads to leaching which is the downwards movement of aluminium and iron oxides

D- Eluviation leaves an ash grey A horizon. Illuviation leads to a reddish brown B horizon