Soil Degradation

Question 1

Damaging agricultural practices

Answer 1

Tilling: short term fertility boost; exposes nutrients and org carbon - uses up carbon faster than replenished to long term loss; loss of soil structure and health

Question 2

Inorg fertilisers

Answer 2

HB process: high energy use and ghg emissions

Phosphate fertiliser: finite resource; high wastage, leaching and inefficiency due to poor soil quality

Question 3

Pesticides

Answer 3

Killing organisms and terrestrial biosphere - need microbes for nutrient cycles
Earthworms help build soil structure
MC important for nutrients to plant

Question 4

Soil structure

Answer 4

Diff size aggregates:
Macroaggregates made of solid matter
Made up of roots and hyphae
Made up of hyphae, bacteria and clay
Made up of humic materials
Made up of clay colloids cemented together

Larger aggregates more stable; smaller ones washed away

Question 5

Woods vs arable land

Answer 5

Larger aggregates in woods; smaller in arable soils and reduced biomass and SOC
Often washed away when fields flooded