Intention:

On one of my first EVA's, Susmita and I collected three soil samples with the intention of using them to plant seeds in the GreenHab. From my experience in the GreenHab it is too hot for plants to grow well and so this idea was postponed. Whilst cleaning the laboratory we discovered some flow chart cards which identified soil types. The intention is to test these three soil samples to determine what soil type they are, to see what variety of soil is in one area to the West of the Hab.

• Equipment
• Sample bowls.
• Electronic scales.
• Pipette.
• Water.
• Sieve.
• Geotechnical gauge
• Soil texturing field flow chart

Method:

Using the electronic scales we weighed an empty container, which weighed in at ensuring that no material larger than 2mm in size was in the sediment. The colour of the sample was recorded. Placing the sample in the palm of our hand we then added water dropwise and kneaded the soil to break down all the aggregates. Once the soil was plastic and moldable we stopped adding water.

We then tested to see if the soil would hold together when we squeezed it. (See table 1.)

We then placed a ball of soil between our thumb and forefinger gently pushing the soil with the thumb, squeezing it upward into a ribbon. We formed the ribbon with a uniform thickness and width. We allowed the ribbon to extend over the forefinger, breaking from its own weight.

We then recorded whether the soil formed a ribbon and if so how long it reached before breaking.

We then excessively wet a small pinch of soil in our palm and rubbed it with our forefinger, noting the texture.

Table 1. Results from testing three soil samples.
Physical Properties	Sample 1	Sample 2	Sample 3
Sample Colour	Light brown	Light brown	Light brown
Does soil hold together when squeezed?	Yes	Yes	Yes
Does the soil form a ribbon?	No	Yes	Yes
Length of ribbon	N/A	>5.0cm	>5.0cm
Sample Texture	Moderately Sandy	Slightly gritty	Smooth

Conclusions:

Using the Soil Texturing field charts in the laboratory we used the above information to identify the types of soil. We identified the soils as:

• Sample 1: Loamy Sand
• Sample 2: Silty clay
• Sample 3: Clay

Evaluation:

Using the flow charts in the laboratory gave us a clear step by step guide to identifying soils which neither of us had ever done before. A way to improve on our experience would have been to try and collect further samples from a variety of different areas, as all the soil samples were from within a very limited area. This would have shown us clearer the difference in soil types.