Читать книгу Practical Field Ecology - C. Philip Wheater - Страница 44

Fortunately, the team had managed to ship liquid nitrogen ahead of time and the majority of it had amazingly survived the long, warm ship transit from Singapore to Diego Garcia. This allowed them to flash‐freeze seawater samples – a crucial part of the processing protocol. However, things only stay frozen if kept below 0 °C. The ship's cook kindly agreed to allow Gareth to store the frozen samples (and the liquid nitrogen) in a large walk‐in freezer on the back deck of the ship, as long as they were properly contained and away from any food. Problem solved.

The next challenge was to construct a laboratory. The solution was to turn a deck container that had been sweltering and rotting in the heat of the tropics for the best part of a year into a workable space for microbiology – a discipline that demands consistently sterile working conditions. This required ethanol, lots of ethanol, a cloth, and some good old‐fashioned elbow grease. Ethanol, fortunately, was not in short supply. Having sectioned off a portion of the container and cleaned it repeatedly, this appeared to solve the problem – provided Gareth repeated the cleaning frenzy on an almost daily basis. Asking the other scientists nicely to stay away from the area with their wet and dirty equipment was also very crucial.

Then came the end of the journey and the challenge to transport the samples back to the UK and keep them frozen when flights, transfers, and baggage handling are largely out of the team's control. Gareth had a small cooler to aid in this process, but key to its success was keeping it cool throughout the journey and at all costs trying to avoid it sitting on a blistering tropical tarmac runway. The team froze sponges in the last of the liquid nitrogen and packed them in to the cooler around the samples, while also accidently freezing part of a colleagues' shoe! They had also frozen Nalgene bottles full of water to act as ice blocks, but ones that have better longevity than your standard home freezer block (the ice is much thicker). These were also packed in the cooler. However, days prior to this, Gareth had realised the ambitious nature of the journey home and the fear of the samples defrosting. Despite extremely limited internet access, he had managed to get an email out to his post‐doc with an emergency request to organise delivery of 2 kg of dry ice to the hotel in Bahrain where they had planned to spend the 9 hours transit time prior to their UK flight. Dry ice is a solid form of carbon dioxide and is around −80 °C. The two 1 kg dry ice blocks kept the samples frozen all the way to Manchester airport and the following 1.5 hour taxi journey to the safety of a freezer.