Hot spots left to cool

日期:2017-07-19 05:21:34 作者:盛咖 阅读:

By Jon Copley FUNDING for the conservation of Europe’s biodiversity is misdirected, according to a botanist at the Natural History Museum in London. Johannes Vogel has identified “hot spots” of biodiversity, sometimes only 20 kilometres across, scattered around southern Europe. These hot spots served as safe havens for plant species by escaping glaciation when the rest of the continent was in the grip of the ice ages. They should be priorities for conservation, says Vogel, but at present they receive little protection. Vogel has examined the genetic variation of Asplenium rock ferns across Europe. Although the ferns are widespread in the north and west of the continent, which was covered by ice sheets in the last ice age, they show little genetic diversity. But Vogel has found 15 sites in the Iberian Peninsula, Italy and the Balkans where more species are present, and where there is much more genetic variation within each species. And the phenomenon doesn’t only apply to Asplenium ferns. “It can also be demonstrated for hedgehogs, fishes—all types of organisms,” says Vogel. The glaciated areas of Europe have not recovered their former biodiversity, even though 18 000 years have elapsed since the ice sheets retreated. Some organisms living near the edges of the refuges will have quickly recolonised their former territory as the ice sheets melted. But those surviving deep inside refuges have moved out much more slowly, struggling to compete with the early colonists. The low biodiversity of northern Europe may be as much due to this as to farming and other human activities, Vogel believes. The refuges have already demonstrated their resilience in the face of climate change. “They are the Noah’s Ark of European biodiversity,” says Vogel. But they can be destroyed overnight by activities such as house building. Unfortunately, they are often overlooked in national conservation strategies, which tend to focus on preserving areas of natural beauty. Vogel wants to see governments develop a pan-European policy to focus efforts and funding on protecting the glacial refuges as long-term safe havens for European biodiversity. Crispin Tickell, convener of the British Government Panel on Sustainable Development, agrees. “Within the European Union, I think it is very important that these hot spots and keystone species should have a means of protection,