One Year Pond Study Week 24: Summer Pollution Study

Summer is slowly coming to it’s conclusion, with the Autumnal equinox and therefore the first day of Autumn falling on Sunday the 22nd of September this year.  I had  a look over my past posts to see what summer studies we needed to do before then and there are three:

  1. Summer night-time pond visit
  2. Summer water study
  3. Summer pollution study

This week we decided to carry out the pollution study.  We tried to replicate our spring one so that comparisons between the pollution in spring and summer were easy.

The first thing we noticed is just how much the water level had decreased.  Here is the level we used last spring:

Only the top of the sign can be seen!

And here it is again this summer:

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And just to emphasize the low water level, the children decided to take a walk:

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This is the post the Heron usually sits on.  It is clear the water has fallen more than a foot.  The Canada Goose then decided to show us himself, just to emphasise!  This is him standing by the sign:

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The children collected a sample of water from the deeper end and the muddy, shallow end of the pond.  We used a simple jam jar and labelled each.  Here is our picture from our spring study:

Both shallow and deep water look clear

The water in the spring was clear, with lots of bubbles.  Here is our water sample from this week:

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The jars had been left for 15 minutes to settle, yet the water was considerably murkier than the spring.  This was reflective of what we had observed for ourselves.  The pond water is dirtier looking, which given how shallow it is at the moment is only to be expected.

We measured the pH of both water samples, using universal indicator paper.  This is how they tested in the spring:

And the result

They measured a pH of 8, which means the pond is slightly alkaline but within limits and therefore healthy enough to support life.

And this was the test this summer:

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The pH remained at 8, so no change there.  We would have been surprised to have seen a change in the pH because even slight changes could render a pond unable to support life, and our pond is currently supporting a lot of life!

Last spring there was very little pollution to be found:

The odd crisp packet

Over the summer, as water levels had fallen there was much rubbish to be found, everywhere:

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Whilst the presence of Lichen is a sign of an unhealthy tree, it is also a sign of good air quality.  This was our Ash tree and it’s lichen last spring, showing a clean surrounding air:

Tree with ivy growing up it

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The Lichen is still present and obviously thriving, so the air quality remains good, in our neck of the woods!

Over the next few weeks we will be completing our summer pond studies with a pond water study and a night time visit.  I will also be reflecting back on the past six months of weekly ponding and marvelling at my own consistency!

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