musicians compose their understanding of nature. to mark the 250000 of verse 3 of the composer's birth i like sharing program with both of my you know he's good. beethoven worldwide. history project starts june 4th on d. w. . mayflies live for about a day. a human being like the 1st century but tree can survive for several south indians. the longest living life on earth the trees and tichina that these woody perennials actually communicate with each other. we visit one of europe's longest untouched primary forests. welcome to tomorrow today this time show on the telly.

there are roughly 3 trillion trees on earth that's around 400 for every human being . fossil discoveries suggest the 1st trees developed more than 350000000 years ago and change the world they increase the level of oxygen in the atmosphere through photosynthesis. pasts in the least take in sunlight carbon dioxide and water and use these to create oxygen and. it's the most important chemical process for life on us. chicks some tough little trees are able to filter synthesize on a significant scale jumps out range get precious little sunlight so how do they survive peter bull even works for the forestry department in germany he raises awareness about forests with the help of distinctly human analogies. mother trees recognize their own offspring and they link up. sugar solution it's basically akin

to nursing. so trees suckle their samplings really. if we take a look below the surface we find fun guy spinning long threads around the trees roots for the fun guy use them to supply the tree with nutrients that it would otherwise be an able to access in return literally supplies the from guy with sugar a system that benefits both sides. from god link up with a number of tree simultaneously resulting in a huge network underground that's become known as the would wide web of. young trees tap into the network and feed off the sugar provided by the older trees. older trees with their large ground supply higher levels of sugar to the networks which is why researchers call them mother trees and remarkably additional fungal thread form connecting them to their offspring so that they receive more nutrients than other trees. of course nursing is

a term that only applies to mammals but it's a similar principle as young trees flourish thanks to sugar supplied by their mothers. forests can carry on growing and regenerating themselves for centuries that if they are left to grow every year an estimated 10000000000 trees that fell. into place no evidence of human interference is known as primary forests these days not many such areas left romania is home to one of the last remaining primary forests in europe tucked away in a remote valley. where in the end they knew the region of transylvania away to a forest that's about a 3 hour drive from the city at sea the a group of scientists is doing field studies here and one of the largest and perhaps most beautiful primary force. in europe. for the scientists this landscape

holds a treasure that is extremely valuable much of it is yet undiscovered. the forest is a virgin landscape that is seen almost no human intervention the boy in me. is really special because it's one of the last valleys. in the temperate zone of europe were is no trail is really wild is really difficult to access. the scientists from the university of prague have been coming here regularly for the past 5 years the remote valley in the fog or rush mountains is an ideal place to do research more than a 1000 hectares of untouched landscape from the mountain tops down to the valley floor that's rare in europe these days. over 95 percent of all european wooded areas are manmade commercial forests so if you want to

understand how a natural forest works you need to come to a place like. only here can scientists study a forest ecosystem in it's original natural form. is really important to. us especially in times off for climate change values like these are the only places where we can really observe that how the pieces we all naturally put on this conditions. after climbing for 3 hours we finally reached the site where the scientists have chosen to count they'll be based here for a whole week from here they can explore the surrounding mountains and study the forest to discover the secrets. that. the next morning the group sets off equipped with numerous measuring instruments they head deep into the forest. making headway

isn't easy. what's more they're clearly not alone. here in their lives you can see the barefoot brains and you can see it's kind of in line in the big so it's going to be any other animal and they're in this place it was possible looking for some insect. 15 bears are thought to live in the boy. but the scientists aren't worried they continue their work undeterred and that involves measuring minute details of the forest they note the number of trees in any given area as well as their age height and species they also calculate the distribution and density of dead wood and they take or samples from the center of the trunks in order to reconstruct the history of individual tree. that looked like

a long needle doesn't it hurt the tree. forest. believes trees do indeed feel pain. every organism can feel pain. otherwise it wouldn't respond to an attack. is that actually true researchers suspect that when a caterpillar nibbles on a leaf that is registered by pressure receptive. the tree then pumps a substance into the leaf that renders it an appetizing and quickly spreads it around to protect the other leaves from the predators well within the tree the relevant information is transmitted electrically as in a human body feast but feeling pain is not just a question of registering and reacting it's an experience it has to have in humans and other animals that involves the brain and scientists have yet to discover the

equivalent in trees. trees do indeed respond to injuries even if they do not feel pain now back to remain here. environment. between 3 of the. mostly 3 and 400 be involved and both are moving. the project started about 10 years ago. in europe's few remaining primary forests scientists selected research plots to focus on these are circular areas roughly the size of a basketball page they now have over a 1000 plots in 9 countries they've taken just under 40000 word samples the group's archive is the largest primary forest database in europe. every year we

spend approximately 3 months in the field we do not have really big groups right now we are here in. 25 people. 3 groups which are split into different valleys. martin make a large is especially interested in looking at how primary forests cope with climate change. the question is could they be at risk in the future. complicated behind it is that the extremes in temperatures are increasing bring in . an increase in natural disturbances such as rolls droughts fires barred middle or breaks does this increase in natural disturbances pose an existential threat to primary forests to answer this question the scientists 1st studies the past how often has boy and meat have been affected by bark beetle or

drought for example in the last few centuries and how quickly was the forest able to recover their findings actually. we found out that the 2nd systems are well adapted and they can for a generate after this. the scientists data reveals that the forest has repeatedly been hit by disaster and yet suffered no lasting damage. because large believes this amazing ability to regenerate is one of the key differences between primary forests and those money by human beings. differently these forests are more resilient than many or commercial in this forest. because even. for high severity a large scale disturbances we can see in our day. at least several

trees to survived even when for example disproves or was disturbed the beach forest was still there and. the combination of the. species after this to. create. divers or composition or a future for. as yet make an action his team don't know if the regenerative power of these natural forest will be sufficient to face the challenges of the future but they remain optimistic more natural growth and diversity also in our commercial forests is likely to be the best protection against the effects of climate change. during the day the forest cools down while at night it's roughly in one degree boom that's when many woodland become active but what it trades do at night if they have

a family and are able to defend themselves do they also see. that was a question sent in by pieces to one from the united states. do trees sleep. we all know the human beings need sleep our inner body clock regulates when we feel tired following the earth's cycle of day and night. animals also have body clocks that set the read them for waking and sleeping. many flowers close their petals and hang their heads at certain times of day their resting periods also follow the rhythm of day and night. but what about trees. well it was only a few years ago that scientists were finally able to answer that question with the help of laser scanners. from dusk till dawn they scanned trees with infrared light

. in each case they found that the whole tree droops that night. the clones of millions of laser scanning points revealed that the position of the leaves and branches changed as the night progressed they moved lower by as much as 10 centimeters. in the morning they gradually returned to their original position. but whether the trees like the animals around them are awakened by an inner body clock is still not clear. but what is clear is that trees do indeed appear to rest at certain times of the day. now it's time to look at the forest fill the roots of trees can be enormous and link up with

other rich systems. that he shows that around 60 percent of all trees worldwide are into linked by networks of fundy threads as we saw and yet these networks are thought to be several 100000000 years old to last the ground beneath our feet may not appear that injuries. but for tree it's a vital source of life. forrester look vic papel and jug free professor clemens geitner pay close attention to the forest floor and what lies beneath it holds the key to a healthy forest. they're going to explain to us the profound influence trees have on the quality of the soil. in a small piece in this old spruce forest they examine the soil to a depth of one and a half meters. of them as if. we can see here the various layers on the surface there are spruce needles the stuff the trees shed it's

a lot sometimes 5 or 6 centimeters deep sixed and. the needles decomposed to create a layer of humus which makes the soil more acidic the room took on the next layer down is the mineral soil with lots of tree roots spruces have very shallow roots and can't access the water or nutrients from lower down that is a disadvantage it means the roots don't loosen the soil or create channels for the humus to trickle down so the spruce can take advantage of the benefits of this good location and importance on. nearby is a mixed forest of coniferous and deciduous trees which look big battle planted 25 years ago the fallen leaves quickly turn to humus. the soil layers here look quite different the earth is looser and crisscrossed by lots more roots. the site is this year and it's if

the roots are much deeper and that's typical for a forest with deciduous trees that means the roots can access much more water the reservoir of vailable to the roots and hence the trees for evaporation and cooling is about 3 times as large and strong for it includes effect. a particular interest of the fine routes through which trees absorb water and nutrients forestry engineer daniel berlant has compared the volume of fine roots from spruce and maple the difference is considerable these 2 clumps come from a maple tree a depth of 10 and 40 centimeters. while these 2 are from a spruce. the more fine roots the tree has the more water it can access. but the scientists also find another difference between the 2 forests the one with deciduous trees as lots of earthworms which help to keep the soil rich and healthy . agricultural scientists on

a curler wants to measure the population of earthworms in this mixed forest. mustard water onto a sample of soil among the deciduous trees drives the worms to the surface as they try to escape the mustard irritates their skin though it's actually not harmful here we see how plentiful the worms are. organic farming has focused our attention in recent years on the role earthworms play in improving soil fertility there's been less interest in their role and forests but it is an interesting question. because where the soil is in good shape the trees will likely be so as well earthworms don't like acidic pine needles a tall but they are drawn to maple leaves for example as they dig maze of tunnels they error rate the soil make it less compact and more porous. bearing symbiotic fun guy also make use of these pop ways what's more the worms help mix humans into

the soil making it easier for plants to access nutrients. so deciduous trees and hans the soil under tract worms when it comes to the challenge posed by climate change it is factors like these that could help make our forests more resilient. limbs are good for the soil and helpful to tree but some animals and insects are damaging to trees especially. then there are cats that. beliefs and then us can impede the growth of the tree when pests arrive on the scene trees defend themselves by pumping toxins into their leaves. amazingly neighboring trees do the same even if they're not under attack forestry expert peter ball even explains the warmer trees talk to each other and

you can understand them by listening in on one for their. does that mean that trees are some kind of language and what exactly do they talk about. it turns out that oaks emit odor signals in response to pest interest ations and those molecules trigger a protective reaction in adjacent trees although it's not clear how this works so but what if the neighbors are on the wrong side wind wise are they then not party to the conversation. that's where the wood wide web comes in trees and signals to the fungus nestling around the roots which relay them via the underground network. this rapidly puts the other trees on alert so that they can prepare their own defenses. but does that count as a language with humans this involves not just exchanging signals but words they convey information through conscious meaning associated with certain sounds so

someone who speaks a foreign language who might not understand sri has been intrigued. so trees do not have language as we understand it and yet they do communicate with each other. and planets has a tree line latitudes to the north and south of which trees are unable to breath in the outside for example there are no sizeable trees and the plants won't traps and moss is. but here 2 days plenty of life in the ground like these lemmings for example. our next report takes us to greenland where scientists are concerned about the fate of these arctic rodents that are something of a barometer for climate change. an hour's flight and they'll reach their destination for ecologist ben why sigler and wildlife biologist your highness lying

it's the final stage of a day long journey def light takes them across greenland's glasses from frozen fields and they see that the pack ice is already starting to thaw although the short summer here has yet to really begin. they'll soon be touching down in the current health valley on the island of trail. even the landing is something of an adventure. they fought along flour sugar milk coffee and tents along with lots of scientific equipment the team are the only humans on the island if they forgotten anything important they'll just have to do without it their return journey is several weeks away until then they'll be camping here in tents. they soon discover they're not alone the tracks of a polar bear shooting one would be the very last resort the team set up an electric fence to keep the bears away. for more lemmings by contrast

a more than welcome they are in fact the stars the very heart of the project the team of course one near the camp ben was that the 1st came to greenland to research lemmings 30 years ago and he's still studying these interesting creatures lemmings are rodents and live mainly in northern regions greenland is home to the arctic learning species in winter white as snow they turn gray and brown as temperatures rise during the summer they live in burrows underground always wary of predators especially arctic fox it's snowy owls. and long tail skewers the lemmings are safer in winter their front grow and enable them to dig through the snow and frozen soil winter is also breeding season beneath a thick blanket of snow they take tunnels and build nests several litters can be

born in short succession only stoats pose a threat as lemmings are able to reproduce when they reach the age of just 6 weeks the population can grow very fast it's those winter nests that ben was sickly is looking for. it's an indirect method to work out how many lemmings live in the area under investigation. as the snow melts the nests become visible this is the 1st winter nest they found. climate change means snow now force later in the year and thaws and that means that the extended phases of large scale reproduction known as lemming peaks have ceased. in good years still low would come across 4000 nests here expedition these days 400 are already a lot. easier means. the lemmings probably have

a whole network of those under the snow which then connect over nests. and their nests or where they reproduced. his team investigates an area of 15 square kilometers every year they cover several 100 kilometers on foot to register the lemming population after just 2 weeks the fuel next to the camp is almost ice free. 3 nests. lurk continues his trek to count nests but he already knows that they are so few in number that the lemming population is unlikely to recover sadly there's a clear trend and one that is documented in detail. in. its july 30th today. to 2. it's rare for such

a research project to have 3 decades of data to work with the findings are further evidence for the painful reality of climate change. incidentally what livings are best known for committing mass suicide by jumping off cliffs is a myth it was make popular by the 950 s. walt disney film white wilderness but the filmmakers actually staged the scene and reportedly pushed the limits of the cliff when was it and his team are working to expose this popular misconception and restore the rodent's reputation. it out on its red white abra the movie i do you have a science question that you've always wanted answered we're happy to help out send it to us as a video text or voicemail if we answer it on the show we'll send you a little surprise as a thank you come on just ask. and

for more stories about the world of science visit us on our website on twitter and facebook. that's all for this week next time on tamara today focused energy how lenses can be placed on solar panels to produce a super concentrated power supply. out

of the comfort zone. into the crisis song theater director mueller overall doesn't shy away from human suffering he demands an incredible amount from both his actors audiences artists activist prices for your milorad on meet the artists are 21. coming up on d w. what's the secret to

a perfectly fried potato. would give some notional dishes their distinctive character. more than. europe's favorite dishes with their small and big secret you know series of feast secrets. of the last. 30 d.w. . like. a mug or just what must. be for the russian soyuz. the state. of so many to. hard. song. and awfully trying

to come straight from the heart. of. the russian intimate journey to death starts june 18th d.w. . the power of forwards. where i come from and i never saw the sun where it took to. having gone up in brazil the sun was always the man since the portuguese word for sun it's masculine and when i moved to germany as a 10 year old i wanted to do it on t.v. that would change how i see the world because into a month of this family. came in the house with the side of a good listener so i was a party to it instead of a deep voice exterminate the guy seemed absolutely incredible. i realized how language shakes thinking how definitions are not only mentality may just put our

whole perception of the role. inside save my life and was one of the reasons i became a journalist i'm a storyteller and i use my words to how quick intercultural on this and my name is in that way and i work and to tell people. this is d.w. news and these are our top stories a passenger jet carrying nearly 100 people is crashing pakistan's largest city. and there are 2 confirmed survivors the rest of the passengers and crew are feared dead several people on the ground were also killed. the number of coronavirus cases across africa has topped 100000 the world health organization says mortality rates in africa are lower than in other read.