Not all blazes are necessarily bad for the environment. Climate change isnt just affecting the rain forest how can we future proof our woodlands in other regions. But 1st tortoises and turtles a fascinating bunch of giant galapagos tortoises can weigh up to 300 kilos sadly many species of these reptiles are in decline only 3 yangtze giant soft shell turtles are thought to still exist and thats even though a lot of these creatures have a very long life spans some live more than 200 years in was from what Tom Valentine wanted to know more. How do sea turtles find their way back to their place of birth. Look ahead to those are globe trotters following ocean currents they can travel more than 100 kilometers a day with their aerodynamic shape on part. Like feet they are in bursts able to exceed speeds of 25 kilometers an hour. They have to come up to breathe every few hours because they have lungs not gills and they go ashore to lay their eggs. Every few years a female sea turtle returns to the beach where she herself hatched digs a hole and deposits a clutch of around 100. 00 eggs in it. Then she leaves the nest and returns to the sea. After a few weeks the babies hatch and follow a light source such as moonlight reflected on the water to reach the ocean. That later return as adults is known as natal homing. But how do sea turtles find their way back from 5000 of kilometers away. Was one theory is that they navigate by sensing our planets Magnetic Field and using it as a g. P. S. System of sorts. A long term study in eastern florida show that the pattern of nesting places of loch ahead sea turtles moved in tandem with subtle shifts in the earths Magnetic Field lines. But is a home beach necessarily a safe one unfortunately not garlands them crows steal the eggs right out of the nest once the baby turtles reach the sea hungry crabs and fish await them. Tourism also upsets the delicate cycle of egg laying and hatching only one in a 1000 hatchlings is likely to survive to adulthood. So why do sea turtles go back to that birth place to nest one hypothesis is that the field. Assume theyll find favorable conditions if they return to the beach where they themselves were hatched the logic being if it worked for me why shouldnt it work for my offspring. Everything is interconnected the ideas of a visionary german researcher and explorer alexander from humboldt continue to influence us today born 250 years ago on september 4th 769 he travelled the world in search of new experiences and insights he recorded his 5 year journey in central and south america in his diary luckily he invented a waterproof ink so his writings even survived a shipwreck on the orinoco and we can still read them today. The last in our series retracing alexander from humble to footsteps takes us to one of the longest rivers in south america the orinoco. When i came the 1st time i was 19 years old and it was amazing to see all these forests and suddenly you can see the whole thing jumping underwater and i fall in love with it would evolve. So i decided to put my life to study the dolphins on the aquatic a system of theory no. This trembling of the air this solitude this wild expanse of the river transports the traveler into adventurous nature. This was a front on both describe the orinoco river. On his Research Expedition he spent 2 and a half months following the mighty waterway documenting its every twist and turn. For the explorers from europe the endless wilderness on land and in the water was a source of continuous wonder and unexpected dangers. Nobody back home expected to return alive from his orinoco expedition. Now if you want to do an expedition the scientists make. The research to move in and you know now yeah they have been basically meant to do that and humbled not to travel from iraq to their new continent a few knowledge about these so we have a lot of things to learn to steal from home will then endurance they bash on the real city and i think this guy is an example for us to put some goals and go behind them. Biologist for an undertow he go as a Research Camp here its the base for the International Expeditions he leads across the entire river network. Covering an area of almost 1000000 square kilometers we already know called base in is one of the largest ecosystems in south america. Scientists come here to study its astonishing diversity of species both in the river itself and in the forests that line at. The basin area is home to 250 different species of mammals and over 100 reptiles finding the animals is no easy task for the researchers many of the creatures are nocturnal and move territory several times a year. If baker across the need or better off grew up here. He sets up cameras in the forest fitted with motion sensors that help to study the behavior of the animals over a period of months. When it has come and i think at the end we can install these camera traps at various heights and this camera records everything that happens here up to a height of 40 or 50 centimeters it enables us to record larger animals such as jaguars tapirs and copy barbarous well now leave the camera here for at least 3 months in. A few kilometers upstream we are in elko squeezes its way through a maze of cataracts. The arts what is rapids are an ecosystem in their own right nutritious algae grow on the rugged. Granite rocks a feast for the fish that pass through year. Over a 1000 different species live in the waters of the orinoco and many of them are exclusive to the river. Here but you know if this place is dangerous. If you dont know the river well you could overturn and drown in the rapids you know what you have a young man drowned over there recently in a good one i thought that that that. Gago no yes ive been fishing here for 40 years my father used to bring me here when i was a kid i wanted to teach my son but hes lost interest in fishing dont get me oh no no no no look the only but. For centuries people here lived off the riches of the orinoco to this day there are still families that move from shore to shore many of them from venezuela they settle wherever there are currently the most fish to catch but the ecosystem here is out of balance increasing river traffic and dam construction have had a disruptive effect on the natural course of the orinoco. We as a human we do need to change your own minds and take care of these places the rivers are unprotected in most countries you protect sometimes the land but the what are the few examples in latin america of government say ok listen lets protect the rivers and and and bikini of Vehicle Systems or and the livelihood of many people are the rivers when we need help to reverse for Healthy People and healthy biodiversity. Increasingly human activities are encroaching on the rivers ecosystems this prompted for an undertow he owed to buy land here a few years ago and turn it into a reserve. Plant and animal species are able to gradually recover here protected from deforestation poaching and environmental pollution. There are long a total. Did come flaked a very wealthy a with the leaves on the bottom. And they didnt know. If they were a lot of time they underwater you know of a Shallow Water and they would be. With this node just there and then if the weather looking for this to play and one of the fish bites they bite yes. Extensive conservation zones help to ensure that a growing number of animals return to the riverside areas as footage from the camera traps confirms. Each of the animals has its own individual pattern enabling the researchers to come and track their behavior. One major success for the reserve is the return of the jaguar to the rain forest the big cats have been under threat due to the loss of their habitat to make way for crop and livestock farming in. My view. And they are not the only species to are found a new home in the reserve. If. I did. It was in no questions. Of the ecosystems everything. In good conditions but now no trouble because everything happens so quickly now they get a vision of the. Fast so if we dont want to lose the species and we need to do Something Like provide conservation and to support as well the national parks. The coffin of animal sounds on the orinoco led to sleepless nights for home board but also to a pioneering concept the animal world faces a constant struggle in which species numbers are constrained by mutual competition. No more than 2 centuries later their equilibrium has been disturbed the animals biggest enemy today is a 2 legged species. During his travels along the orinoco humboldt also confirmed that there was a link between the orinoco and amazon River Systems the rio. And his journey through the rain forest he wrote you find yourself in a new world in wild and untamed nature nowadays there are few places left on this planet under stirred by human activity. Devastating fires have been raging in the amazon rain forest for weeks such huge blazes are unusual here. The. I humidity and the lush vegetation usually prevent flames from spreading but in the past few years things have changed the Worlds Largest rain forest has become more vulnerable to drought due to Climate Change. Many of the current fires were caused by humans. Loggers use fire to clear underbrush and dried Indigenous People from their land. Farmers set blazes to gain land for their cattle and to grow crops but the soil itself isnt all that fertile its the intact forest ecosystem that so efficiently recycles nutrients the amazon is a reservoir for 150 gigatons of Carbon Dioxide and now the fires are releasing huge amounts of c o 2 into the atmosphere. Astronaut newcomb parmitano observed the forest fires in the amazon from the International Space station and photographed the thick smoke trails. These red dots give an impression of the number of fires burning on a single day their impact on the rain forest is devastating in comparison the problem in Southern Africa seems far worse. But the blazes seen here are for the most part savanna fires grasslands need the flames to renew themselves grass burns fertilizing the soil and making way for new growth. On facebook we ask you to tell us what you think about forest fires have you ever been affected by one. K. P. Pandy from india writes fire is a good servant if its controlled but a bad master if its beyond control forest fires and Global Climate change are a vicious circle global communities need to break this cycle by promoting Renewable Energy technology. And reducing deforestation and forest degradation. From ecuador posts the fires in the amazon are nothing compared to the 1000 time bigger devastation the forest has undergone over the past 40 years the fire is the desperate cry of a jungle that has been mutilated by the interests of multimillionaires and a few government beneficiaries it has turned the eyes of the world to the rain forest before she disappears. From indonesia lets start a movement everyone should plant at least one tree if its chopped down will plant a new one. Thanks for your comments. There are more than 4000000000. 00 hectares of forest worldwide they cover 30 to 40 percent of the earths surface. The most densely forested countries are russia brazil canada the us and china more than half of the planets woodlands are located there but for decades forests have been disappearing at an alarming rate Climate Change pasts and fire do less damage than humans who continue to flee or for us to create farmland. And thats even though forests can help prevent mudslides and stop soil erosion. Forests protect. Carbon dioxide around 10 tons per hectare of land and they produce oxygen for us to bring. Their home to 80 percent of all land welling animal and plant species the trees collect huge quantities of water whatever reaches the forest floor is stored there or is filtered as it seeps away. Forests can cool the air in cities by up to 8 degrees celsius acting like a huge air conditioning system but not. Every species of tree has the same cooling properties. In the future what types of forest will best stand up to Climate Change. This to city was woodland next to an old spruce plantation has a special function to help combat Climate Change. But will it really outperform the spruces. Researchers in austria using these devices to study the spruce and maple trees. They want to know if one of the 2 woodlands remains cool in the summer how much particulate matter the trees fell to from the air and how well they grow during the hot dry summer up to now a little data like this has been collected. These sensors measure the temperature. Analyzes the data so far he has no concrete findings but hes developed a hypothesis the. Maple trees have much deeper roots and spruce trees do so when hot and dry weather like weve had this summer and the roots can tap more water from the deep in the ground and draper as the water on the surface of the layers and thereby effectively cooled all surrounding air. That makes that the city was forest a better Economic System the surrounding area and communities benefit from the fresh air and cool air. For more than 40 years ranger patent has been concerned with devising the best kind of woodland to cope with hot and dry summers. Here in the area in southern germany the bark beetle has destroyed vast swathes of spruce trees. Now and paddle is restructuring the woodland he and his colleagues are planting wild fruit trees deciduous trees indigenous to the forest. We need clean water we need healthy air with low levels of particulates and we need protection against erosion. And every forest should provide that so we have to manage our woodlands well and take care of. His idea is to plant particular types of forests for particular functions the 1st is the energy forests. Fast growing poplars that can be used in the local wood chip power plant for heating and electricity. Stephon vic cop would Energy Expert is examining how much biomass can be produced by poplar trees. Theyll still produce shoots from their roots or stumps after theyre felled thats why one tree can be harvested several times each sector of Poplar Forest can produce the equivalent of around 5000 liters of heating oil per year the trees also cleanse the atmosphere absorb Greenhouse Gases and help ensure clean drinking water. Point 2 meters thats a fair amount for an 11 year old tree. 50 percent of germanys energy is used to produce heat and what is ideal for that purpose we can burn it with a very high yield support for. The scientists to researching how much wood and how much bark the popular generated and how much energy can be produced from it in the ideal. Only the wood would be used for Power Generation the bark produces more fine particulate the researchers are working on new harvesting methods leaving the bark behind in the forest along with the leaves to rot and feed the soil with nutrients. Back in the climate protection forest which cattle planted 25 years ago the researchers are still comparing the deciduous and spruce forests. As examining whether the trees grew during the hot summer months 1st he looks at the maple tree. In the upper curve you see the circumference. Expanded by 15 millimeters 45 millimeters in diameter. And how well did the spruce grow. Do you circumference of the grew about 4 millimeters as it more than one millimeter in diameter you very much. After. Until now heat was regarded as the crucial factor in determining a trees growth here in germany more and more attention is switching to the importance of water following recent heat waves trees can grow only when they get enough water. And only then can the forest in turn help make rain as they grow trees release water vapor through their leaves. Amid sense. Clouds seeds water vapor is the posited on the turpins creating rain drops and rain. Without the water vapor would needlessly evaporate into the atmosphere. Findings show that the city was forests cope with dry summer months better than the old spruce forests. I hope we can turn things around in time oh man we need to futureproof our forests so they can keep providing us with fresh air and clean water. If our blood is red why arent i oh my ok to have it do you have a size question that youve always wanted and said were happy to help out yes send it to us as a video text ovoid smell like we answer it on the show will send you a little surprise as a thank you come on just ask. Find as i do w dot com slash science or drop us a line at t w underscore site on facebook d w dot science. Thats all for now next time we focus on food and ask algae provide a sustainable alternative to meet tune in to find out more see you then. Its a classic among germany 50 trips frankfurt but its exciting contrasts from the skyline to be all selling and from the severn culture around the spider calls ever voice said im feeder to try to the nightlife in the station district. Coming up on. The venice film festival. A director who takes pride in his gun reliance. And we can look forward to some quality move. Beyond ask you streaming good for film and bad for cinema. Ok dennis the truth comes on. 30 minutes on the c. W. And we dont even know. When your family scattered across the globe. To. Turn back to the roots you should get a minimum of. The shots family from somalia live around the world from one of them needed urgent assistance and. The family starts october 25th on d w. They had a real trial that resides. I come from viet not so people in fact more than a bit in the tooth of blood not just democracy thats one. Reason why im passionate about people and aspirations and they can. Post in the report is right here in burning on the floor of the burning born and i remember thinking at the time if the barley in the world can forward anything could happen if people come together and unite for a call. But i do the news that often confronts difficult situations more conflict between does something still i see just want my child to confront but he does on policies and development put the spotlight on issues that matter most congo to security oppression missionizing. The north has come to achieve so much more needs the job and i feel people have to be at the heart of solutions my name is on the top shes on and i work at g. W. This is data where you news and these are our top stories at this hour russians have been voting in municipal elections which opposition politicians say were neither free nor fair president Vladimir Putin cast his vote in the capital where antigovernment demonstrations arrested in race and weeks protestors were angry after authorities banned several opposition can