Our December was mild despite Storm Barra arriving on the first day of the month. Ireland and the North of England were hit badly with up to 6,000 homes without power, ferries cancelled, floods and fallen trees causing havoc. The Lizard had many cloudy, windy and wet days but plenty of sunny days as well. The autumn colours were still strong and plenty of plants were still growing and forming new foliage for next year, the grass was still lush and verdant. The ferns became more visible in the hedgerows and banks as other plants and bushes died away. Hart’s tongue was busy unfurling its leaves, side by side with the male and the lady fern. The lichens were out in all their glory, covering the bare leaf trees, rocks and stones. Naturally the obvious presence of the ferns and lichens got me thinking about the story they might tell me about our field and its health. I started my voyage of discovery with the lichens.
From the information that I’ve gathered, lichens can provide us with valuable information about the health of the environment as they are sensitive to air pollutants. As canaries were to the coal mine, lichens are to nature; they absorb their nutrients directly from the atmosphere and the rainwater and with it any harmful pollutants in the air and rain. Lichens grow everywhere, in Britain alone there are over 1,500 species, but in the 19th and 20th centuries, as cities expanded and air pollution worsened, lichen diversity dropped in London from 130 to 1. Since introducing restrictions on sulphur pollution in the 1980’s, more varieties have re-colonised the city but the diversity is still very low. (Courtesy of Kew Gardens).
However, here on The Lizard, (and Cornwall in general), with its clean air, ancient woodland and granite rocks, it is thriving, along with the ferns and an abundance of moss. I counted 6 different species on the trees lining the riverbank. A mixture of foliose, fruticose, crustose and beard lichens and yes, I do now need to get a lichen identification book and look further into the woods for more species. Lichens offer food and shelter to a wide variety of organisms; inverterbrates, birds and mammals. They are a combination of algae and fungus; the fungus is the species that provides shelter to the algae and the algae provides food for the fungus. A perfect relationship and it gets better; algae produce up to half of the oxygen in the earth’s atmosphere – very handy for those of us who breathe and without fungi in the root system, 80 to 90% of trees and grasses would not survive, if they go, so do we. In addition to these talents, fungi also assist us in many processes of food production: making bread, wine, beer, cheeses etc. To be blunt, we need to look after the welfare of lichens and become more aware of the scandalous amount of pollution that infects our rivers, seas and lands. Coal burning used to be the main killer of lichens, (and therefore of many other species), but as that has declined the overuse of synthetic fertilizers and high volumes of animal manures, have become the major drivers of biodiversity loss in the UK, with additional help from the petroleum refineries and cement manufacturing. They are all powerful contributors to global warming and cause harm to the health of animals and humans. Canaries were used in coal mines up until the 1990’s, as an early warning signal for toxic gases. The birds were highly sensitive and would become sick before humans, allowing the miners to escape or put on protective respirators. If we don’t check in with the health of this part algae, part fungus, we might not have time to escape.
On a more uplifting note, we celebrated the winter solstice, the astronomical end of autumn and the beginning of winter, on the 21st of December, the day with the shortest period of sunlight and the sun at its lowest point in the sky for the year. It was a beautiful evening but the number one joy at this moment is knowing that the days now begin to grow longer and longer, bringing more warmth and light into our lives. What a day to celebrate.
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