biosphere

Question 1

what is leaching

Answer 1

where soluble material is washed down from one soil horizon to the one beneath with gravity. lots of leaching can lead to upper mineral horizons becoming less fertile

Question 2

what is capillary action

Answer 2

where moisture moves upwards in a soil. where evaporation is faster than rainfall.

Question 3

what is decomposition

Answer 3

the breakdown of plant derived material into its simpler organic parts. done by soil boots and enzymes

Question 4

what is humification

Answer 4

the complete breakdown of plant remains leading to the formation of the different types of humus

Question 5

what are the different types of humus

Answer 5

mull, moder and mor

Question 6

when does mull humus form

Answer 6

develops under deciduous woodland where plant remains are actively broken down by a prolific soil biota (lots of soil biota)

Question 7

what is moder humus

Answer 7

the intermediate between mor and mull

Question 8

when is mor humus formed

Answer 8

usually develops beneath coniferous woodlands under a cool, wet climate condition. breakdown is slow due to lack of soil biota

Question 9

what is weathering

Answer 9

weathering is the breakdown and decomposition of rocks and minerals by factors including air, water, sun and frost.

Question 10

what is translocation

Answer 10

the movement of material in solution or suspension from one horizon to another

Question 11

what is eluviation

Answer 11

downward movement of material where rainfall is more than evaporation (E= exit)

Question 12

what us illuvistion

Answer 12

accumulation of material in one layer of soil which have been leached from a layer above (I- into)

Question 13

what factors form soil

Answer 13

climate, time, living organisms, events

Question 14

what part does climate have on soil

Answer 14

warm temps allow rapid decomposition of material into soil whereas cold temps limit the growth of plants and slow decomposition making soil less fertile

Question 15

what effects do living organisms have on soil

Answer 15

worms and other creatures help to mix and improve the soil by encouraging air into the soil and encouraging breakdown of organic material. the more soul biota the richer the soil

Question 16

what effect does time have in soil

Answer 16

it can take 200-400 years for 1cm of soil to form. therefore the older the soil the deeper it is

Question 17

what effect do events have on soil

Answer 17

events like volcanic eruptions and floods can displace soil and limit what can grow on it

Question 18

how is brown earth soil formed

Answer 18

the deciduous forest vegetation provides deep leaf litter which is broken down rapidly by the warm climate. the trees long roots go deep into the soil accessing nutrients from the lower layers. the soil boots ensures the mixing of the soil, aerating it and preventing the formation of distinct layers. the climate impacts the formation as precipitation exceeds evaporation meaning there is alot of leaching and the possibility of an iron pan forming. brown earth soil tends to be found in gentler leading to lower rates of erosion (so thicker soil)

Question 19

how is podzol soil formed

Answer 19

the low temperatures of the climate lead to slow decomposition so the needles from the coniferous woodland produce acidic mor humus. the high rainfall leads to leaching and forms an iron pan between the A/B horizons. the iron pan may impede causing water logging. eluvation leaves an ash grey A horizon. and illuviation leads to a red/brown horizon. the lack of soil biota leads to well defined horizons and podzol soil is found on steep slopes.

Question 20

how is gley soil formed

Answer 20

gley soil is found on gentler slopes, cool to cold climates which lead to a very slow rate of decomposition. the plant roots don’t go very deep so there is a limited recycling of minerals back to the vegetation. not much soil biota. the limited soil biota in the soil extract the oxygen they needs from the iron compounds meaning the soil has a blue colour due to anerobic condition. the impermeable clay texture impedes drainage and caused water logging. poor drainage is the key soil forming feature for this soil type

Question 21

what is the hydrological cycle

Answer 21

the water cycle involved water that is being evaporated, moving around in clouds or in surface run off to other places. the water is never lost, only moved around. the water cycle shows the continuous movement of water within the earth and atmosphere

Question 22

what are inputs to the hydrological cycle

Answer 22

an input is something that puts moisture/energy into the hydrological cycle system eg. solar energy

Question 23

what is storage in the hydrological cycle

Answer 23

something that stores moisture within the hydrological cycle eg. lakes, glaciers, evaporation

Question 24

what are transfers within the hydrological cycle

Answer 24

things that transfer moisture from one place to another eg. glaciers, evaporation, condensation