Tuesday, 16 June 2015

30 Days Wild | Day 14 - doing some science!

On day 14 of 30 Days Wild, I did some science! Well I made a start on doing some science. I've nearly finished my BSc in Environmental Science now, and only have my final project to work on over the summer. We have to plan and execute a piece of research investigating the effect of an abiotic (non-living) variable upon a biotic (living) variable. I am quite interested in phenology (the timing of seasonal events) so I am conducting an experiment to investigate the effect of raised temperatures (there's your abiotic variable) upon the date of first flowering (and your biotic) in the common grassland wildflower, Bird's-foot Trefoil (Lotus corniculatus). My hypothesis is, not surprisingly, that plants experiencing higher temperatures will flower earlier than plants in ambient air temperatures. Bird's-foot Trefoil is an important food plant for the larvae of several butterfly species, so any shift in its flowering date, potentially induced by climate change, could have knock-on effects upon the lifecycle of butterflies which feed on its buds and flowers - some of which e.g. Silver-studded Blue are already in decline.

Bird's-foot Trefoil (Lotus corniculatus), currently in flower along my canalside commute.
I'd planned the method for my experiment earlier this year, and had been growing a load of Bird's-foot Trefoil from seed in preparation. Partly due I think to the disappointing weather we've been having of late, the seedlings had taken a lot longer than I was expecting to harden off. However they were ready this weekend and the experimentation could commence! I am putting two sets of 25 plants outside in my garden; one set is inside a mini greenhouse to raise the temperature and the other is just outside in ambient temperatures - however these plants are still covered by an awning of clear plastic to protect them from rain, so I can control how much water each set of plants receives. Due to the difference in temperature and wind between the two sets, they may consume water at different rates, so I'll have to closely monitor this and try to water them taking this into account. Gotta ensure the only variable that could be affecting when they flower is temperature!

Ambient temperature - also protected (hopefully) from birds, insects etc. to some extent by netting.
Raised temperature.
I've put a thermometer with each set of plants so that I can record the daily maximum and minimum temperature from each. I need to try and make sure the temperature in the mini greenhouse is around 2 - 4 °C higher than outside, in line with climate change predictions. I made a mini Stevenson screen from cardboard for each thermometer sensor to shield them from direct sunlight, was quite pleased with those!

Homemade Stevenson screen covering the thermometer sensor!
The thermometer body inside a bag to protect it from damp.
Each plant is numbered so that once they start flowering (assuming this happens - my main concern!) I can record which ones are in flower. Once they have all flowered (fingers crossed) the experiment will be finished and I can do some stats to see if there is a significant difference in first flowering date between the two sets of plants. I might also try some different stats to see if there is a relationship between temperature and first flowering date - although as I only have two temperature treatments this might not show much of use. 

The wee plants.

Been spending a lot of time thinking about and planning my experiment over the past few months so I'm excited to finally start collecting data! I'm hoping it will go smoothly and show something interesting :o)

GOD SPEED, experiment!

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