Forgotten my disk again..
More soil stuff. Makes a change from sociology at any rate!
Soil Water:
a) Weigh 10g of soil
b) Place soil in small pots and reweigh. Record results
c) Place pots in oven at a temperature of 95°C, to evaporate moisture, for two hours
d) Remove from oven and reweigh. Record results
e) Percentage moisture content can be worked out thus:
weight of wet soil - weight of dry soil X 100
weight of wet soil 1
Record results
Organic Content:
f) Place dry pot of soil in oven at a temperature of 200°C for two hours to burn off organic content
g) Remove from oven and reweigh. Record results
h) Percentage organic content can be worked out thus:
weight of organic dry soil - weight of non-organic dry soil X 100
weight of organic dry soil 1
Record results
Texture:
a) Take a sample of wet soil and compress until no more water is released
b) Mould it into a ball
c) Using a metre ruler, measure one metre above a solid flat surface
d) Drop the ball of soil from a height of one metre
e) If it retains it’s shape it is considered clay; breaks apart, sand
Composition/Particle Size:
a) Using a pestle and mortar, grind up an 8g soil sample to remove lumps
b) Sand, silt and clay will be separated
c) Place soil in sieve and shake
d) Noting sieve size, record weight of soil in each sieve compartment
e) Given that sand equals a size of 63m or above and silt and clay equal less than 63m, record the weights of the different soil types.
f) Calculate and record the percentages of the different soil types
Acidity:
a) Take one test tube
b) Add barium sulphate to the first dotted line (about 1cm)
c) Add soil sample to the second dotted line (about 1cm)
d) Top up to the third dotted line with pH indicator solution (about 3cm)
e) Seal the test tube with the second bung and shake well making sure the constituents are thoroughly mixed
f) Allow the test tube to stand until the soil has settles out leaving a coloured solution
Very fine soils may require a further addition of barium sulphate to improve the time of the settling process.
g) Compare the colour of the solution with the pH indicator chart by holding the tube alongside the colour bands about 2cm away from the white of the card. Estimate between colours where necessary. Direct sunlight should be avoided when making comparisons.
Soil Water:
a) Weigh 10g of soil
b) Place soil in small pots and reweigh. Record results
c) Place pots in oven at a temperature of 95°C, to evaporate moisture, for two hours
d) Remove from oven and reweigh. Record results
e) Percentage moisture content can be worked out thus:
weight of wet soil - weight of dry soil X 100
weight of wet soil 1
Record results
Organic Content:
f) Place dry pot of soil in oven at a temperature of 200°C for two hours to burn off organic content
g) Remove from oven and reweigh. Record results
h) Percentage organic content can be worked out thus:
weight of organic dry soil - weight of non-organic dry soil X 100
weight of organic dry soil 1
Record results
Texture:
a) Take a sample of wet soil and compress until no more water is released
b) Mould it into a ball
c) Using a metre ruler, measure one metre above a solid flat surface
d) Drop the ball of soil from a height of one metre
e) If it retains it’s shape it is considered clay; breaks apart, sand
Composition/Particle Size:
a) Using a pestle and mortar, grind up an 8g soil sample to remove lumps
b) Sand, silt and clay will be separated
c) Place soil in sieve and shake
d) Noting sieve size, record weight of soil in each sieve compartment
e) Given that sand equals a size of 63m or above and silt and clay equal less than 63m, record the weights of the different soil types.
f) Calculate and record the percentages of the different soil types
Acidity:
a) Take one test tube
b) Add barium sulphate to the first dotted line (about 1cm)
c) Add soil sample to the second dotted line (about 1cm)
d) Top up to the third dotted line with pH indicator solution (about 3cm)
e) Seal the test tube with the second bung and shake well making sure the constituents are thoroughly mixed
f) Allow the test tube to stand until the soil has settles out leaving a coloured solution
Very fine soils may require a further addition of barium sulphate to improve the time of the settling process.
g) Compare the colour of the solution with the pH indicator chart by holding the tube alongside the colour bands about 2cm away from the white of the card. Estimate between colours where necessary. Direct sunlight should be avoided when making comparisons.