SOIL I LOVE SOIL AAAAAAAAAAAAA🪨🪨🧱

for all u soil lovers out there 🤎🤎🤎🇫🇴

what are the layers 🧅 in a soil profile called

Horizons

storages in lithosphere

• organic matter

• organisms (US‼‼🧍)

• nutrientes

• sales minerales

• air

• agua

6 stages of nitrogen cycle (transfer)

• atmospheric nitrogen ~80%

• nitrogen fixation by bacteria in LEGUMES🗣🗣🫛 - ammonia

• absorbed as proteinssss 🥩💪

• then death - Dead Organic Matter

• then NITRIFICATION: soil ammonium goes to nitrites then nitrates through oxidation

• nitrates converted to gas - DENITRIFICATION - by more bacteria what icons 🧫

3 types of weathering (transformations)

• physical: freeze-thaw: it’s physical

• chemical: e.g. acid rain: it’s chemical

• biological: e.g. fungi, roots: it’s biological

What 5 qualities of soil are likely to lead to higher productivity?

1. Greater porosity: water/air volumes

2. Good drainage to prevent water logging

3. Abundant soil biota (e.g. nitrogen-fixing bacteria)

4. Neutral-slightly acidic pH

5. High nutrient density/fertility

properties of sand

• larger particles = better aeration and water movement

• but consequently poor water and nutrient retention

properties of clay

• smaller particles = better water and nutrient retention

• also an ELECTRIC CHARGE⚡which attracts the water and shit

• BUT awful at infiltration - leads to waterlogged soil

both are bad by themselves which is why we need LOAMS🗣🗣

4 steps to determine the mass of inorganic compounds in soil

1. warm a soil sample to 100℃ to evaporate moisture

2. Weigh the mass of the sample

3. burn the soil sample at under 500℃ (so the inorganic matter doesn’t melt)

4. weigh what remains and compare w original mass

4 ways that soil fertility can be reduced?

• deforestation

• overgrazing (happened in uplands)

• urbanisation

  All 3 of these reduce volumes of Dead Organic Matter

• intensive farming: nutrients not replenished at rate they are used

4 results from soil fertility reduction?

Plants die = soil more exposed to the elements

• soil erosion

• salination

• desertification

• Toxification (no bacteria or plants to absorb)

5 ways of reducing soil erosion

• long term crops: don’t need frequent replanting = less soil disturbance, better cover. grassland, tree crops

• zero-tillage cult䷂ivation: less soil disturbance as seeds drilled directly into the soil

• contour ploughing: at 90° to slope - disrupts water flow - soil deposited in furrows

• terracing - prevents erosion from heavy rain on steep hillssss

• windbreak like at the beach it stops the elements 👌

6 factors which influence Sustainability of terrestrial food production

• scale

• industrialisation

• mechanisation

• fossil fuelllllll

• seed

• water use

what % of earth’s land is cultivated ?

25% -millennium ecosystem assessment 2005

3 Benefits of non-animal agriculture

• Lower trophic levels are more efficient - have greater yields per energy input

• lower cost

• Reduced overgrazing from livestock

• we use too much land and water for agriculture: 40-50% of all available freshwater

5 way we can improve food sustainability?

• produce more food locally

• eat less meat

• make better labels to allow CONSUMER CHOICE what a lie

• monitor food production (OPEN THE DAMN BOOKS 🗣🗣)

• plant buffer zones to absorb nutrient runoff