Thursday, 5 September 2013

Azores field course 2013

The 2nd year Biological Sciences students are currently on a week-long field course on Sao Miguel island in the Azores archipelago. In the last few days the students have carried out two plant surveys on the island's volcanic slopes, sampled and analysed water samples from four lakes, spotted the endemic and rare Priolo bullfinch and seen a new species of spider!

Here’s a bit more about what we’ve been up to so far…
View from Sierra da Tronqueira where the students carried out endemic plant surveys

Day 1: Lagoa do Fogo
Rob Parkinson talking to students about the island's formation
On our first morning we visited Lagoa do Fogo – one of the island’s calderas. These are remnant volcanoes that have exploded all their magma, and have now become freshwater lakes, fed by rainwater. Here we were investigating differences between leaf physiology of endemic and native plants compared with non-native invasives. This is an important question, as the Azores have a higher proportion of non-native plant species compared with native species, than anywhere else in the world (69% of plants are non-native).

On the slopes of the caldera the students measured leaf parameters including chlorophyll fluorescence, thickness, light transmission, and they also took dental impressions of the undersides of leaves to analyse stomatal density later in the lab.

Measuring leaf thickness of Rubus

Some Syrphidae activity
 After lunch we headed to Sete Cidades, another caldera, to take some water samples. The lakes have no streams flowing in or out, so there is little movement of water. This means that pollutants washed into the lakes with the rain run-off will accumulate. Usually there is a distinct colour difference between the two lakes (the larger one being bluer, and the smaller one bright green), but this year both lakes were very green.

Lakes at Sete Cidades, with cyanobacterial blooms 
Despite the signs of pollution, we did find dragonfly nymphs and crayfish in the greener of the two lakes. There are reports that the crayfish often have occluded eyes due to the pollution, though this wasn’t obvious of the specimens we found. The students will be analysing the water samples on Wednesday to assess the water quality and to look for cyanobacterial blooms.

Despite the pollution we did find dragonfly larvae and crayfish in the lakes

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