Paper 1 Practicals

Question 1

How do u measure bulk density of soils?

Answer 1

Bulk density=dry soil mass
Dry mass-weighing soil after it’s been heated at about 100 degrees Celsius to constant weight

Question 2

How do u calculate percentage water content?

Answer 2

Percentage water content equals wet soil mass minus dry soil mass divided by dry soil mass (times 100)

Question 3

Why are lichens good for studying atmospheric pollution?

Answer 3

Normally present
Normally common
Easily seen
Easily identified
Generally distributed
Can be used to measure acid rain pollution
10 by 10cm quadrat

Question 4

Describe the process of measuring organic nutrients in water

Answer 4

Nitrate/phosphate test strips
Sample directly downstream and upstream of field
Multiple samples at each site for statistical analysis
Standardised position in river

Question 5

Describe the how the process of measuring water turbidity can be standardised

Answer 5

Using secchi disk:
Same dimensions of disc and shading in all locations
Same light levels (light meter)
Measure depth when segments disappear

Question 6

Describe how to measure the impact of inorganic nutrients on plant growth

Answer 6

Min 3 concentrations of inorganic nutrients
Nitrate added
Same number of seeds per test
Same species of plant, (duckweed) per test
Genetically uniform