Tutorial 7 : The importance of soil quality

Question 1

soil formation

Answer 1

development of soil from parent materials (sediments), also known as pedogenesis

Question 2

soil protection

Answer 2

conservation of soil properties and quality

Question 3

European Soil Strategies for 2030

Answer 3

framework to restore soil by 2050, with actions that need to be put in place by 2030

Question 4

soil degradation

Answer 4

decline in soil quality and fertility due to various factors, such as erosion, pollution, loss of organic matter

Question 5

soil health

Answer 5

the overall condition of soil in terms of its physical, chemical and biological properties

Question 6

soil quality indicators

Answer 6

parameters that can be measured to make assessments on the health of the soil

Question 7

nutrient cycling

Answer 7

neutral processes through which essential nutrients like carbon, nitrogen and phosphorous are recycled and made available to plants and other organisms in the soil ecosystem (carbon cycle, nitrogen cycle,…)

Question 8

blue water

Answer 8

water from streams, rivers, lakes, groundwater aquifers,…

Question 9

green water

Answer 9

water that penetrates the soil after rainfall

Question 10

soil remediation

Answer 10

restoration from the soil via different techniques

Question 11

types of soil remediation

Answer 11

• thermal soil remediation
• air sparging
• encapsulation: encapsulates the contaminants (not good for agriculture)
• bioremediation

Question 12

bioremediation

Answer 12

use of biological mechanisms for remediation
the contaminated soil is treated at the site with aerobic and anaerobic bacteria that have been engineered specifically to consume and break down pollutants
not always possible in extreme climates

• phytoremediation: it happens through the plant, contaminants are absorbed from the soil
• phycoremediation: it involves algae
• mycoremediation: it involves fungi
• bacterial remediation: it involves bacteria

Question 13

biochar

Answer 13

from the charcoal produced by heating biomass in the absence of oxygen

can be added to soil to improve quality

Question 14

plant-soil-microbiome interaction

Answer 14

complex relationships between plants, soil organisms which influence plant growth and nutrient cycling and overall ecosystem functioning

Question 15

root biofilms

Answer 15

microbial communities that form biofilms on plant roots that play a role in nutrient uptake

Question 16

soil organic matter

Answer 16

partially decomposed plant and organic residues, microbial biomass, and other organic material in the soil

Question 17

soil organic matter formation

Answer 17

occurs through the decomposition of organic materials; degraded by soil organisms such as bacterial, fungi, earthworms

Question 18

mycorrhizal fungi in soil organic matter formation

Answer 18

fungi that have a symbiotic relationship with plant roots; help with nutrient uptake and help from organic matter; fungi secrete hyphae which then make up organic matter glomalin soil protein

Question 19

mitigation of food contamination in agriculture by mycorrhizal fungi

Answer 19

fungi can immobilise metals in soils, restricting to transfer to plants

Question 20

soil biota

Answer 20

everything that lives in the soil. Refers to micro- and macrobiota

microbiota refers to various microorganisms living in the soil
macrobiota refers to soil fauna and other plants that are visible to the naked eye

Question 21

soil fauna

Answer 21

various animal organisms living in the soil (worms, insects,…)

Question 22

antimicrobials and antimicrobial resistance

Answer 22

antimicrobials are substances that inhibit the growth or kill microorganisms, including bacteria, viruses, fungi, and parasites.

antimicrobial resistance refers to the ability of microorganisms to resist the effect of antimicrobial agents, leading to treatment failures and public health concerns

Question 23

antimicrobial resistance in soils

Answer 23

antibiotics runoff into the soil and microorganisms develop resistance

Question 24

humic acids

Answer 24

large molecules that improve soil quality and plant growth.
form solid pieces when acidified
act as prebiotics, feeding beneficial bacteria in the gut

Question 25

fulvic acid

Answer 25

smaller molecules that enhance nutrient uptake and cell energy
remain dissolved at all PH levels

Question 26

nitrogen cycle

Answer 26

nitrogen fixation through bacteria (nitroh=gen is converted to ammonia)
Ammonia is used by plants as nutrients
nitrogen-fixing plants -> working together with microorganisms which fix nitrogen into the soil

1) Nitrification: plants can convert nitrogen to nitrates
2) Assimilation: plans and bacteria working together to transfer nitrogen to plant
3) Ammonification: decomposition of plants and animals, and nitrogen is converted to ammonia
4) Denitrification: bacteria convert nitrates back into nitrogen, releasing it back into the atmosphere

Question 27

phosphorus cycle

Answer 27

1) Weathering: rocks release phosphate minerals into the soil through weathering processes
2) Absorption: plants absorb phosphate from the soil through their roots, incorporating it into their tissues
3) Consumption: animals obtain phosphorous by eating plants or other animals
4) Decomposition: when plants and animals die, phosphorous is released back into the soil through decomposition
5) Leaching: Phosphorous can be washed away from soil into water bodies through runoff
6) Sedimentation: phosphorous settles at the bottom of water bodies, where it can become part of sedimentary rocks over time

Question 28

carbon cycle

Answer 28

1) Photosynthesis: plants absorb carbon dioxide from the air during photosynthesis, converting it into organic carbon compounds
2) Consumption: animals obtain carbon by consuming plants or other animals
3) Respiration: plants and animals release CO2 back into the air through respiration when they break down organic compounds for energy
4) Decomposition: when plants and animals die, decomposers break down their organic matter, releasing carbon back into the soil or water
5) Combustion: human activities, like burning fossil fuels and forests, release CO2 into the atmosphere
6) Carbon sink: some carbon is stored long-term in oceans, soil, rocks, and fossil fuels, which act as reservoirs that can exchange carbon with the atmosphere over long periods

Question 29

arbuscular mycorrhizal fungi

Answer 29

type of mycorrhiza in which the symbiont fungus penetrates the cortical cells of the roots of a vascular plant, forming arbuscular

Question 30

thermal soil remediation

Answer 30

• in-situ treatment
• works best for soil that has been polluted by either contaminated water or hydrocarbon compounds like petroleum products
• contaminated material is heated to 650-900C in a primary treatment unit to the point where hydrocarbon impurities and water evaporate

Question 31

air sparging

Answer 31

• large amounts of air are injected into a contaminated soil stratum to force organic vapours outwards where they can be treated by carbon filtering
• applied directly to the soil
• used for removing hydrocarbon pollutants

Question 32

encapsulation

Answer 32

• separates contaminants and stops their spread instead of filtering them
• the contaminant source is covered with layers of lime, concrete, clay caps, or synthetic textiles that limit precipitation’s infiltration
• usually a last resort technique