Biosphere Higher Geography HomeLearning Pack Created by Mr

Biosphere Higher Geography Home-Learning Pack Created by Mr Das

Learning Intentions + Checklist: Topic I can describe and explain the effects of climate, relief and drainage on the formation of podsols, brown forest soils, and gley soils I can recognise and describe the properties of soils from a soil profile I can draw annotated diagrams to describe the properties of podsols, brown forest soils, and gley soils, referring to horizons, colour and texture Key-words

Distribution of Soil Types Describe the global distribution of the 3 major soil types (4) Refer to the following in your answer: A) Continents/countries/regions B) Hemisphere C) Overall patterns/trends D) Correlation with forest type

Factors affecting Soil Natural vegetation — deciduous forest vegetation provides deep leaf litter, which is broken down rapidly in mild/warm climate. Trees have roots which penetrate deep into the soil, ensuring the recycling of minerals back to the vegetation. Climate — precipitation slightly exceeds evaporation, giving downward leaching of the most soluble minerals and the possibility of an iron pan forming, impeding drainage Relief — greater altitude results in temperatures and the growing season being reduced an increase in precipitation. Steeper slopes tend to produce thinner soils due to gravity. Soil organisms — soil biota break down leaf litter producing mildly acidic mull humus. They also ensure the mixing of the soil, aerating it and preventing the formation of distinct layers within the soil. Rock type — determines the rate of weathering, with hard rocks such as schist taking longer to weather, producing thinner soils. Softer rocks, eg shale, weather more quickly. Drainage — well drained with throughflow and little accumulation of excess water collecting, producing limited leaching.

Case-study- Relief, Soils and Scotland • • • Soils are influenced by relief, altitude and slope steepness Soil accumulation will slow down at altitude due to greater precipitation and other variations in climate South facing slopes are warmer and drier than North facing slopes, leading to warmer soils more suitable for human use. Steep slopes will contain thin, less developed and drier soils. Steep slopes have more surface run off therefore more soil erosion Gentle slopes and flat land are prone to waterlogging as it takes water longer to infiltrate (water on grounds enters the soil) the soil In the northwest, the Hebrides, the Shetland Islands, and other areas, the soil is poor and rocky, and cultivation is possible only at end of rivers Peat is widespread on moors and hills. Areas with good, arable land have largely been derived from old red sandstone and younger rocks, as in the Orkney Islands, the eastern Highlands, the northeastern coastal plain, and the Lowlands

People and Soil The way people use and cultivate land can affect the quality of soil, especially the nutrients present. Soil takes thousands of years to develop but can quickly be ruined by human activity. Natural loss occurs via leaching, erosion and mass movements but today the natural balance of soil is being upset far more frequently. Soil erosion caused by overcultivation and more intensive agriculture Trees help hold soil in place, so when they're uprooted, winds and rains push the loose soil and rocks to streams and rivers, again resulting in unwanted sedimentation. Challenge Question: Explain some of the strategies to prevent soil erosion taking place

Watch this short video and answer the questions: 1. An example of soil under threat 2. Two causes of soil erosion/degradation 3. Two solutions

Factors affecting Soil 1. Complete a detailed mind-map on the factors affecting soil, above. 2. Use your information to write a model answer to the question on the right. BUG it first! 3. Bonus- how do people affect soil? (2 reason) 4. Take this test- Explain the factors that affect soil (5 marks) ……………………………………………………………………… ………………. . . . . . . . . . . . . . . . . ………………………………………………………………………. . . . .

What is soil made up of? There are 5 key ingredients. . .

Soil is made up of 5 ingredients: 1. Water is held in the porespaces and carries dissolved salts- plant food

3. Air in the soil carries gases to and from the plant roots and animals. It is in the porespaces when water is not. 4. Soil Organic matter (SOM). It comes from plant and animal remains that are gradually broken down into a brown material called humus. It is the major source of the three main plant foods- nitrogen, sulphur and phosphorus. It holds water, improves soil structure and provides the energy for plant ( and animal ) growth.

Short Quiz: 1. How might rocks turn into soil? (2) 2. What does 'porosity' mean? (1) 3. What is Soil organic matter a source off? (2) 4. How are animals living in the soil be useful? (1) 5. Write down the 5 ingredients of soil, and for one of them explain why it is an ingredient. (6) /12

Soil profiles Below the surface all soils are made up of several layers. These layers and their composition varies between different soil types. Some soils can be very deep (several metres) with many layers others can be one very shallow layer. The composition of the soil determines the land-cover above and the organisms that are able to survive.

Sketch this diagram and add the labels to the appropriate part: The C horizon is weathered rock. Beneath the weathered rock is the solid rock This layer is made up of dead organic matter such as leaves The B horizon is primarily made up of minerals leached from above The A horizon is made up largely of humus. Extension: next to each statement, write down an extra point of detail. See next slide for example

This layer is made up of dead organic matter such as leaves The A horizon is made up largely of humus, organic material that forms in soil when plant and animal matter decays (extra point example). The B horizon is primarily made up of minerals leached from above The C horizon is weathered rock. Beneath the weathered rock is the solid rock

We are now going to learn about: 1. Podsols 2. Brown Earth 3. Gley

Remember, soil is made up of different layers of horizons. You will need to learn these for each of the 3 soil types.

Answer: Podzols are commonly found in mountainous/upland areas.

Podsol Soil Profile 1. Sketch the profile of Podsol. Use the template below to help you.

Podsol Soil Profile Remember the following: Top horizon which consists of decaying organic matter from the vegetation above. The two layers below, the A and B horizons, are made up from the products of the AO horizon, and are greatly influenced by the soil forming processes, thus resulting in distinct colours, texture and water content. The C horizon at the bottom contains the parent material.

Podsol Formation Task Create a key, similar to the below: • Red: soil organisms • Green: vegetation • Blue: climate • Purple: parent material (rock type) • Black: drainage/relief (these are very closely linked) In the next slide, you will see a series of boxes relating to the formation of Podsol. Colour/higlight each box to correspond to the factor in the key For example, if it is to do with soil organism, highlight it red. Once finished, draw arrows connecting each box to the appropriate part of your diagram.

Example: The climate is cold and wet. Precipitation > evaporation which causes leaching and waterlogging. Podzolisation can also take place making the soil acidic. In the C horizon parent material is generally weathered fluvioglacial material with a mixture of particle shapes and sizes.

Copy and complete using word-bank and BBC Bitesize for help: https: //www. bbc. co. uk/bitesize/guides/zq 4 rr 82/revision/2 Key-words decay mix too cold • Podzol soils are found underneath. . . . (Christmas trees). The conditions in these areas tend to be. . and …. . The horizons of this soil profile are …. . There are 2 reasons behind this. Firstly, …. . . . occurs- leeching of materials from the upper horizons to the lower horizons occurs. Secondly, it is too. . . . for. . . . . (earth worms) to survive and …. . up the soil. • The Ao horizon houses …. . . . because of the coniferous trees above. They. . . slowly because of the climate and this creates an. . . …. . • The A horizon is. . . …. . . . due to …. . Eluviation takes place here because of the. . . …. . . and snow melt which washes nutrients …. . . • The B horizon contains. . . . , …. . . and. . . as there are illuvial deposits. These minerals create a. . . . colour. • The C horizon is …. . . in colour and. . due to the type of parent rock found here. • Overall, there are no earthworms to mix up the soil layers. The soil tends to be thing and not suitable for farming so is used for. . • Unlike other soil profiles, an E horizon is found between the A and B horizon. This is a layer of …. . . Hardpan is formed because the iron oxides and Aluminium cement- this impedes (stops) drainage (Drainage is …. . . ). Answers coming next week. coniferous trees Soil biota (soil organisms) well defined cold and wet hardpan poor leeching pine needles Heavy rain acid mor humus. ash coloured podsolization aluminium, iron and clay grey reddish acidic

Brown Earth Soil Profile 1. Sketch the profile of Brown Earth. Use the template below to help you.

Brown Earth soils are found in Europe, Russia and North America. They are found in mild and damp conditions. This is a very fertile soil, so is often used for agriculture because it can support high population densities. It contains no hardpan so drains freely. Soil organisms, like earthworms, mix the materials together, merging the boundaries between the horizon. They have a brownish colour due to being well-leaced with a dispersion of aluminium and iron oxides

Colour code these boxes according to the key on slide 24: ● Thin soils on steep slopes Brown earth form due to gravity Natural vegetation is deciduous woodland ● Oak, ash, birch, chestnut ● Lose leaves in autumn ● adds rich organic matter to soil - humus Earthworms and other animals active meaning what? They develop best under vegetation that causes less acidic (MULL) conditions- like deciduous trees. These create a thick leaf litter which decomposes quickly Semi permeable (allowing water to penetrate through pores) parent material such as sandstone, limestone and boulder clay. Deep roots take up minerals from it. Cool temperate oceanic climate. Soil temperature always above 0 degrees ● lack of freezing temperatures means micro -organisms are active on gently sloping and low lands ● land is well drained & allows biological activity Higher humus content in lowland areas ● south facing slopes (sunnier)

Brown Earth Properties Brown Earth soils are found in Europe, Russia and North America. They are found in mild and damp conditions. The very top layer is nutrient rich because of the abundance of decaying grasses. Mull humus is formed here due to the quick decomposition due to the mild climate. The A layer is well aerated. This is because the soil biota create pores and channels as they move. IT is dark brown in colour as humus replaces any nutrients that are leechedleeching tends not to happen here. Leeching is minimal due to the rate of evaporation and transpiration being so similar. The B Horizon is light brown due to a lower humus continent. The C Horizon has varied parent material. With brown earth soils, tree roots often reach down and penetrate the parent material to extract nutrients. This is a very fertile soil, so is often used for agriculture because it can support high population densities. It contains no hardpan so drains freely. Explain the factors that affect Brown Earth (5 marks). Use the mind-map above to structure your answer. You can draw an annotated diagram. Example: Natural vegetation: ………………………………………… ……… Climate: …………………………………………… …

Comparison Exercise Using the diagram on the left and your notes, explain 5 key differences between Brown Earth and Podsol: Example: Differences in climate, natural vegetation, parent rock, biota etc.

Gley Soil Profile 1. Sketch the profile of Gley. Use the template below to help you.

Gley Soil (the Scottish Soil) Gley soils represent the most extensive soil cover in Scotland. These soils are found on gentler slopes or in areas of high rainfall where the water does not drain away readily.

Match the heads with the tails: Gley Soils are found in northern and tundra areas, therefore. . . The very top horizon is dark, and humus organic matter decays. . The B Horizon is a blue/greyish colour due to. . . The C Horizon (parent material) is impermeable clay therefore. . Drainage is poor here as the A and B horizons are often frozen, therefore. . . Horizons tend to be mixed due to Land use is restricted due to low temperature. The conditions are anaerobic- there is little oxygen. The humus is black and acidic. cold climatic conditions and permafrost (permenantely, carbon rich frozen soil). continuous waterlogging from the permafrost. to intermittent freezing and thawing(melting). This causes the soil to become waterlogged due to permafrost (soil that is frozen for extended periods of time). to cold climatic conditions and permafrost. leading or glacial till, leading to waterlogging which contributes to the blue grey layer

Gley Soils • Gley Soils are found in northern and tundra areas. This causes the soil to become waterlogged due to permafrost (soil that is frozen for extended periods of time). • The very top horizon is dark, and humus organic matter decays slowly due to the low temperature. The conditions are anaerobic- there is little oxygen. The humus is black and acidic. • The B Horizon is a blue/greyish colour due to continuous waterlogging from the permafrost. • The C Horizon is impermeable clay. • Drainage is poor here as the A and B horizons are often frozen, causing them to be water logged. Horizons tend to be mixed due to intermittent freezing and thawing(melting). Land use is restricted due to cold climatic conditions and permafrost.

Remember- gley soils are found in cold, upland climates Climate: These are soils of a very cold, wet climate. Waterlogging also occurs where there is permafrost that impedes drainage. Angular rocks found in B horizon due to frost heave where material is displaced upwards by the expansion of freezing water in the soil. In colder climates they can have a poorly developed set of horizons caused by freeze thaw weathering. Vegetation: Mainly mosses and lichens. Breaks down very slowly in the cold climate, leading to an acidic (MOR) humus Few plants can grow due to lack of oxygen Biota: Very few soil organisms live here because of the cold temperatures, therefore there is not much mixing. Their upper layers are blue-grey in colour as a result of Gleying. This is when the iron turns blue due to lack of oxygen (which is used up by soil bacteria) in the water. Relief and drainage: They often are found on flat land, further contributing to the waterlogging. Waterlogging denies soil oxygen, preventing organisms living there. Red/Orange mottling present due to iron deposits in B horizon. Parent material is thick, impermeable clay leading or glacial till, leading to waterlogging which contributes to the blue grey layer.

End of Unit Glossary: Biosphere -a reference to the totality of the earth surface and atmosphere that is inhabited by living organisms. Capillary action-the upward movement of water through a channels in a substance. In geography, most commonly the upward movement of water through a soil. Catena-sequence of soils on a slope where the differences between them are a direct function of the change in slope. Chernozem -soil type often found in continental interiors with a temperate grassland biome type. Coniferous woodland -woodland or forest made up of softwood trees having common characteristics such as an evergreen appearance, waxy needle-like leaves and usually producing seeds within cones which open to allow dispersal by wind. Denitrification -the conversion of nitrates to nitrogen in soils by bacteria which thus leaves the soil low in nitrate and therefore less fertile. Eluviation -removal of material from a soil horizon, usually downward. Gleying - in soils that are waterlogged, reduction of ferric iron to ferrous iron takes place changing the colour of the soil from reddish brown to bluegrey. Hardpan -a thin crust of material within a soil as a result of the illuviation of iron and/or aluminium from layers above or the precipitation of calcium carbonates which cement sands together. Humus -the decomposed organic element of the soil. Is identified both as an independent horizon in some soils, or in the clay-humus complex. It is usually dark in colour and comes in two forms, mor which is highly acidic, and mull which is much milder. Illuviation -inward movement of clays, minerals and organic matter to a low soil horizon From one above. Leaching - the removal of minerals in solution from soils when water moves down through the soil and drains away. Mor -a humus layer with high levels of acidity. Dark, even black in colour, not fully decomposed and lacking in nutrients. Mull -a dark, crumbly, nutrient rich humus layer. Nitrogen cycle -series of flows in an ecosystem which move nitrogen between various stores and allow it to perform functions essential for life. Podsol - soil type found in cold, wet climatic areas in high latitudes. As precipitation exceeds evapotranspiration the soil becomes waterlogged and minerals are leached from the upper layers into the lower layers. Soil profile -the variation in soil characteristics through its depth. Zonal soil - soils that have been under development for a very long period of time and therefore show characteristics clearly attributable to the biome

Fill out the table using your notes with key differences between the 3 soils: Factor Climate Parent Material Natural vegetation Relief Biota/soil organisms Podsol Brown Earth Gley

Revise for the test: Please use the following resources to revise for the upcoming test: 1. https: //blogs. glowscotland. org. uk/ea/public/Do on. Academy/uploads/sites/42/2016/03/Physical. Environments-Biosphere-Revision 1. pdf 2. https: //www. bbc. co. uk/bitesize/topics/zmbd 7 t y 3. http: //www. sfu. ca/geog 355_1137/mmacin ne/Soils%20 and%20 their%20 main%20 characteri stics. pdf Remember to comment on soil-forming processes related to relief/drainage, parent material/rock, natural vegetation, biota/soil organisms and climate