In the almost (gosh, better get a move on) two years since I started my PhD I’ve become accustomed to the general response I get when I combine “environmental sciences”, “seaweed” and “atmosphere” in the brief blurb that makes up my layman’s job description. It seems that if you mention the word environment + ‘anything’ then that ‘thing’ immediately becomes a harbinger of doom. After all, the environment is in trouble is it not??
Let me reassure you right now people, algae is not about to bring about the next apocalypse. In fact haven’t we discussed in the past that algae is going to cure obesity and malaria? But, as with most things, when humans meddle with the ecosystem what is natural and harmless morphs into a massive problem. Ladies and gentlemen; the slime fields of Brittany.:
These algae blooms are nothing new, they happen in Brittany most years, but this year appears to be particularly bad. Now, I’m not going to go into full-blown science explanation here (although if you want to know more please just comment below and I’ll try to help) but here’s a little intro into why this is occurring:
1. In the same way that humans need vitamins and minerals to survive plants and algae need nutrients too. Major plant nutrients are nitrogen and phosphorus in the forms of nitrate and phosphate. Except algae can’t just pop to Holland and Barrett for a vitamin supplement when they’re feeling peaky. No nitrate, no phosphate, no growth.
2. Nitrate and phosphate, unsurprisingly are key ingredients in fertilisers we apply to crops. This can either be organic (for example manure) or inorganic (made chemically in a factory). Whichever floats your boat fertilisers are important; without them we wouldn’t be able to feed half the people we do on this earth or grow those weird-giant veg people love at country fairs.
3. The issue comes with the fertiliser that doesn’t stay in the field, the stuff that gets washed, rinsed and leached into local waterway, bigger rivers and eventually the sea. Here it provides a massive pulse of nutrients to the algae.
4. Some species of algae are what we term ‘opportunistic’, they’re adapted to dealing with nutrient inputs and can bloom rapidly when we get a flux of nutrients. It’s a bit like an all-you-can-eat Chinese buffet for the algae when this fertiliser arrives and soon the coast is covered with the stuff that is not only smelly and unsightly but toxic too. Not great when you rely on sandy beaches for your thriving tourist industry.