ASSIGNMENT

Question 1

What is the AIM of your project?

Answer 1

• To determine the porosity of my peat soil samples against non-peat soil samples to display any comparisons between them.

Question 2

What is the 1st section of your UNDERLYING ENVIRONMENTAL SCIENCE?

Answer 2

• Soil is the mixture of organic and mineral matter spread across the Earth’s surface that acts as the “natural medium” to enable land plant growth and habitat for soil biota/macro - and microorganisms.
• The structure of soil comprises key components:
  1. minerals (approx. 45-49%),
  2. organic matter,
  3. water,
  4. air,
  5. gas.
• These key components undergo several physical, chemical and biological interactions and processes to form soil, through the decomposition/erosion of parent material, alterations in the mineral composition (i.e., through hydrolysis) and the fragmentation of soil from organisms (i.e., plant roots).

Question 3

What is the 2nd section of your UNDERLYING ENVIRONMENTAL SCIENCE?

Answer 3

• Further, peat soils are soils derived from partly decomposed organic matter originated from plant material, predominantly peat mosses (Sphagnum).
• These peat soils form through the processes of waterlogging and incomplete decomposition of organic matter due to constant rates of high rainfall and lower temperatures (in temperate climate zones).
• Due to this, the partly decomposing organic matter (i.e., plants) accumulate more over time and receive little to no oxygen, forming anaerobic conditions that ultimately allows for peat to form.
• The uses of peat can range from its applications in horticulture as a compost or for electricity generation as a fuel.

Question 4

What is the 3rd section of your UNDERLYING ENVIRONMENTAL SCIENCE?

Answer 4

• Soil porosity refers to the amount of pore/open space that exists in between soil particles (i.e., sand, clay and silt) and indicates how much water can be absorbed. The diameter of these soil particles include:
  1. Sand: 2.00 - 0.05mm
  2. Silt: 0.05 - 0.002mm
  3. Clay: < 0.002mm.
• Soil porosity is highly important as it determines the presence of oxygen and groundwater within the pore spaces of soil for plant respiration which can affect overall plant and crop growth.
• Research suggests that peat soils are highly porous and contain high percentages of porosity, ranging from 80-95% porosity and are vital in helping to retain moisture and act as effective forms of carbon storage.

Question 5

What is the METHOD of your project?

Answer 5

• For the field investigation, I travelled to two different locations at the Whitelees Wind Farm to gather two large peat soil samples, one from a stream/burn and one from within an accessible forestry site, using a shovel, plastic tubs and bin bags.
• I then collected 2 smaller garden samples, one located near the garden’s stream and one located nearer to plants, as a second field investigation using the same appropriate equipment.
• Once my samples were collected, I then proceeded to conduct both of my experiments using measuring cylinders for 100ml of water and beakers for 100cm³ of each soil sample, where I had to fill the beaker up to the top of my soil sample and write down how much volume of water was left in the measuring cylinder.
• The formula I used for this experiment to calculate soil porosity was:

Porosity % =(Volume of water added/total volume) × 100

Question 6

What is the ANALYSIS of your project?

Answer 6

• The results of my experiment show that the soil porosity for both peat and non-peat soils display approximately the same values with slight variations.
• The porosity for the Garden A soil sample was lower than the Peat A and B samples, with the mean value being 28.84% compared to 31.65% and 31.96%, whereas the porosity for Garden B was slightly higher with 32.32%.
• Both soil samples show low soil porosities which goes against the research that found that peat soils are highly porous materials of up to 95%, highlighting a discrepancy in my findings against the underlying environmental science.

Question 7

What is the EVALUATION of your project?

Answer 7

• For the field investigation work, soil samples were taken from digging into the peat soil with large samples collected whilst smaller surface soil samples were taken from the garden, both using a shovel. However, for this work I could have controlled and analysed the porosity of my soil samples from varying depths (i.e., 20cm, 40cm, etc.) as a better measure of control and distribution of soil porosity.
• Further, when undergoing the experiment, more caution could have been taken when putting soil in the beakers to ensure that the soil was properly compacted to prevent any air bubbles that could have impacted the results.
• Additionally, I could have taken precautions when storing my soil samples that any remaining soil moisture content in the soil, especially if any precipitation/rainfall events occured previously, through methods such as pre-drying my soil samples were reduced and allowed for more accurate readings to be taken.