Periglacial environments and human activity

I have found it very difficult to find information relating to human activity in periglacial environments. Most information I have found mostly relates to glacial environments or periglacial environments and climate change. However, I have still managed to find some information which relates to human activity within periglacial environments.

First of all, it is important to outline the challenges that humans face in this physical environment:

- Very low temperatures

- Low precipitation rates

- Short summers which means short growing seasons

- Presence of permafrost

- Thin, poorly developed soils

- Long periods of snow on the ground

- Blizzards

- Waterlogging in the summer due to the thawing over permafrost layer

When teaching this, it would be good to ask the class for ideas of the challenges humans would face in periglacial environments given what they have already learnt about them. Putting this list up on the board would be a good start and then you could ask students to work in pairs to come up with some problems humans may face, for example building settlements, getting food etc.

The Problem

The main problem of living in periglacial environments is soil temperature. Almost every human activity involves the production of heat which can have a detrimental effect on the underlying ground – the heat may melt the underlying permafrost and so lead to a thermokarst landscape.

The Solution

Houses – those that are built in these environments are raised up and off of the ground on wooden piles. This then allows for air circulation between the building and the permafrost to avoid heating the ground. The piles are cemented in and allow for the contraction and expansion of water which makes them more stable throughout the year.

Roads and runways – These may be made of gravel which prevent large amounts of heat from being transferred to the ground. Runways and some roads are also painted white to reflect solar energy which stops heat from being transferred to the soil

Pipes – The problem of moving sewage and water through these environments has been solved through the creation of utilidors. These are insulated boxes which are raised on low pilings carrying pipelines for water supplies, sewage pipes, heating pipes etc. They have to be above ground as if they were buried they would freeze and would also be affected by the seasonal thawing and freezing in the active layer.

Human impacts

All of these methods that have been created to allow humans to live in this environment can have negative effects. In order for settlements to be established, ground is often cleared which results in a reduction of insulation and in the summer then results in a deepening of the active layer. With regards to transport, there is a risk of oil spills and vehicles damaging vegetation around the area. Another major impact is that of over-hunting. As many populations rely on native wildlife for food, continuous hunting of the same animals may eventually lead to a reduced population and thus have a negative multiplier effect on other wildlife species and vegetation.

This work on human activity could be made more enjoyable for students by getting them to create spider diagrams and mind maps, for example:

The diagram above is one I made as an example of what the pupils could create to develop their ideas. Red arrows indicate the problems and green arrows indicate the solutions to these problems. Pupils may find some ideas over lap and is good to get the students engaged with the topic.