Trees don't only combat climate change, prevent soil erosion, serve as shelter, provide oxygen and food, some are even equipped to deal with the consequences of drought and fire.
Image: picture-alliance/blickwinkel/J. Hauke
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While humans and animals stand some chance of moving out of the path of an encroaching fire, the story for plants and trees is an altogether more inert affair. Bound to the ground by the roots that feed them, they have no choice but to stand still and wait for the flames to have their heated way.
But some trees, though scorched, charred and perhaps on first glance, given up for dead, have found a way to adapt to the infernos that form part of the pattern of life in their parts. Most notably several types of Eucalyptus.
Indigenous to Australia, which is well known for its roaring bush blazes, many of the tree's species have developed an unusual feature known as a lignotuber. These organs, which can measure several centimeters in diameter, are large outgrowths that surround the base of the trunk either underground or at soil level.
Shoots of green among the charred trunksImage: Getty Images/L. Dawson
Essentially storehouses of dormant buds and vascular tissue, if the top of the tree whose base they encircle is destroyed by a fire or drought, lignotubers come into their own, vigorously promoting the growth of new shoots, thereby keeping the tree alive.
As if that were not smart enough, in order to channel as much available energy as possible into the regeneration project, some trees shed large parts of their old root system, only maintaining those parts needed to anchor the deminished yet revived plant to the ground.
Trees: our green lungs and so much more
The International Day of Forests is a time to appreciate our green surroundings. This year, it focuses on renewable energies, past and present, highlighting our oldest renewable: wood.
Image: picture-alliance/blickwinkel/K. Irlmeier
The call of the woods
Forests, woods, groves, copses... all of these woodland areas take centre stage on the International Day of Forests on March 21st. The day was proclaimed by the United Nations in 2012. With its annually changing themes, it is all about raising awareness of forests and their diverse uses. This year the theme is "Forests & Energy."
Image: picture-alliance/Arco Images/J. & A. Kosten
How much wood would a woodchuck chuck...
Forests are the basis for many types of energy. When used as a fuel, wood can come in handy in solid, gas, and liquid form. Woodfuels such as solid firewood and charcoal, wood gas, and liquid bio-oil or bio-ethanol provide one in three households worldwide with energy. That equals 2.4 billion people globally. Woodfuels' primary domestic uses are cooking, heating and boiling water.
Image: picture-alliance/dpa
Woodfuels as renewable energy
Good old forests and the fuels they generate are ancient, yet sustainable sources of energy. They account for approximately 40 percent of our global renewable energies. In contrast to fossil fuels, the emissions that are set free into the atmosphere when burning woodfuels are later removed again when trees are planted, because they make use of and store CO2.
Image: Fotolia/maho
Smoke is the deadly downside
About 50 percent of wood is used for energy purposes each year, mostly just burnt for fuel. This percentage rises to 60 percent in Asia and 90 percent in Africa. But the smoke causes problems, particularly for people's health. 4.3 million people die every year because of indoor air pollution. That is more than deaths from malaria, tuberculosis and HIV combined.
Image: Reuters/M. Al Hwaity
Working with wood
Woods are an important source of employment. In developing countries, around 883 million people base their livelihoods fully or partly on forests. With new, advanced biofuels picking up, this number could increase - also in developed countries.
Image: picture-alliance/AP Photo/J. Holden
From chopped wood to pellets?
The popularity of pellets and briquettes has significantly increased over the years - in 2015, 28 million tons were produced. They are not only smaller and easier to handle, they can also be produced from other feedstock, such as grasses or waste-sawdust. Another benefit of the energy carrier: compared to liquid or gas from fossil fuels, pellets are safer to transport.
Image: German Pellets
A shady spot in the sweaty city
Wood is only good for heat? Not necessarily. With our planet heating up, trees can also act as coolers. In overheated cities, trees can cool their environment down by up to eight degrees Celsius (14 degrees Fahrenheit). As a consequence, cooler city air requires less energy for air conditioning in buildings. The trees are working their magic again.
Image: Public Domain
Logging threat to planet's green lungs
The rainforest plays a key role in sequestering CO2. The key Amazon rainforest is under threat from deforestation as trees are felled and areas cleared for farming, mining or construction projects. Scientists warn that these forests must be saved if the world's climate is to be protected.
