Ecology Topics

Ecology

Hidden secrets in the world's most northerly rainforests

2012 AUG 3 (VerticalNews) -- By a News Reporter-Staff News Editor at Ecology, Environment & Conservation -- Olga Hilmo knows. As a biologist and researcher at the Norwegian University of Science and Technology (NTNU), she has made it her business to better understand the treasure trove of genetic diversity that is protected in the tiny fragments of boreal rainforests that still remain. The key, she says, is realizing that this fantastic diversity is hidden in plain sight, in the organisms that drape tree branches in long tendrils of green or grow on bark and rocks in crusty or leafy patches of green or grey.

These organisms, called lichens, are actually two or more species living together in a symbiotic relationship, where a fungus provides the structure and an alga provides nutrients. In a study just published in Molecular Genetics, Hilmo and her colleagues from NTNU's Museum of Natural History and Archaeology and the Nord-Trondelag University College report extremely high genetic diversity for individuals of one lichen species, Lobaria pulmonaria, that grow on the same tree.

Hilmo and her colleagues' findings are important because they show that genetic diversity can persist, even if the species in question is found only in tiny fragments of once plentiful habitat, like northern rainforests.

Hilmo's findings matter because they provide us new information about a globally threated species that has somehow managed to survive in what's left of Norway's boreal rainforests. These rainforests are like small islands in a sea of tree plantations and harvested areas, with plantation trees cut every 70-80 years.

Less than 1 % of the productive forest area in Namdalen, an area in central Norway with some of the world's most northerly boreal rainforests, is still home to this rare habitat. Here, annual precipitation can top 1350 mm per year, and it rains on average about 230 days of the year. As a result, humidities are always very high and the forest canopy rarely dries out - making for a wholly unique habitat for humidity loving species such as Lobaria.

In spite of the favourable growing conditions, there are essentially no untouched boreal rainforests in Norway, Hilmo says. And changes in logging practices in Norway after WWII have reduced the area covered by natural boreal rainforests, she says. "All these forests are affected by logging in one way or another. Before WWII there was selective logging, but after WWII they went to clear-cutting. Most natural stands have been left in ravines where it is too hard to log," she says.

33 fragments protected

The good news is that species like Lobaria have managed to maintain high genetic diversity in these small fragments, and that logging around them does not appear to be having a negative effect on the rainforest fragments. Because of this, Hilmo and her colleagues hope that foresters and loggers in Norway can find ways to protect these remaining bits of forest, which are important reservoirs of diversity.

She also hopes that there will be more funding in the future to further explore the diversity of Norway's rainforests. "We need to know a lot more about the species that grow in these forests, particularly rare species such as Lobaria," she says. "If we want to establish targeted measures to protect these species, we need to know much more about them, both in terms of their ecology and population biology."

Local and regional authorities have recognized the value of the remaining forests, and 33 fragments have already been protected on a regional basis. Additionally, landowners who want to log in natural boreal rainforests must report their plans to the authorities, she says. Nevertheless, the more that people understand that there are these special forest fragments in central Norway, the better, she adds.

"These forests are fantastic," she says. "There are moss-covered logs all over the ground, and lichens draping tree trunks and branches, and pendulous lichens hanging down from the trees. It's fascinating and beautiful. Everyone should get to experience being in a rainforest like this, especially in the rain."

Keywords for this news article include: Ecology, Norwegian University of Science and Technology.