disasters -- they've always been the three main reasons for human

migration. but technological progress and new forms of transportation have made displacement a far bigger, global issue. in the mid-19th century, in order to escape starvation in their home countries, millions of irish and germans boarded steamships to the united states. in the 20th century, the second world war forced 60 million people from their homes in europe alone. and since 2005, millions of people have fled conflict in syria. sometimes, like in africa today, all the causes of flight come together at the same time. take mali, for example. since 2012, violence has overshadowed the west african country. islamists regularly atta malian government forces and u.n. peace-keeping troops.

over the past few years, 250,000 malians have fled to neighboring countries. now some of them are returning home. reporter: the calm in timbuktu is deceptive, and it's mainly down to the massive presence of u.n. peacekeepers. rebels and jihadists are still operating in northern mali at the edge of the sahara desert. terror and violence have left their mark on the city. there are too few hospitals, and many children are no longer attending school. mariam and fatouma touré are ambassadors for unicef, the united nations children's fund. they are 15 years old and are still in school. in timbuktu's old town they regularly visit families to persuade them to send their kids back to school. mariam: we go from door to door to make parents aware of how

important education is. we've already persuaded a few to send their children to school. but there are parents who say that education is not important for children. and then some of them say that it's more important to go to koranic school. reporter: not only parents' objections like these are keeping children out of school. fear is also a factor. more than 800 schools that shut down after the political crisis in 2012 remain closed, more than 80 in and around timbuktu alone. the sidi mahmoud school is open and hopelessly overcrowded. mariam mint mohamed ali is 12 years old and one of around 1000 students here. most of them are children from the neighborhood. some had fled the violence but have since returned, like mariam. mariam: my family left timbuktu in 2012.

we lived in a refugee camp in mauritania. life was very hard there. we didn't have a proper house, just a hut. it was very windy and very hot in the camp. it was hard. reporter: there are up to 100 children in each class. mariam's teacher abdoulaye bakaye says the returning refugees need extra special attention. abdoulaye: we have to work with them on two levels. on the one level we have to support them psychologically because so many of them are traumatized. on the other, we have to give them extra tutoring so they can catch up with the other pupils. many of the refugee children have missed an awful lot of school. reporter: there's not just a shortage of schools in timbuktu, but also of teaching staff.

teachers have to contend with threats from the islamists who want to stop non-religious education. few children here are getting the chance to finish their schooling. mariam: i'm really happy. there's a proper school here with desks, teachers, and books. i'm so glad i have the chance to learn here. host: an 8000-kilometer-long belt of trees stretching along the edge of the sahara from mali through niger to ethiopia. that's the goal of great green wall project. the idea is that the plants will prevent further desertification, make soils more fertile, and reduce conflict. and it's urgently needed. bamako in mali, for instance, has a booming population, and deforestation in t region continues.

reporter: charcoal is big business in bamako, the capital of mali. almost everybody needs charcoal to cook with, and the population is growing. maimuna traoré is a charcoal merchant. she is doing well, but her very success is becoming a source of concern. maimuna: there are fewer and fewer trees. it is scary. if you go out of town, you will see what i mean. reporter: an australian agronomist with the ngo world vision, tony rinaudo, has developed a method of countering the deforestation that affects large parts of africa. his work won him the right livelihood award, also known as the alternative nobel prize. tony: as land is cleared of the vegetation, the land gradually degrades and become less and less productive. less can be grown on it and less

profit can be made from it and people become more desperate. so, there is a very strong link between conflict and land degradation, and also between migration and land degradation. reporter: maimuna traoré tells rinaudo that she now has to get her charcoal from 160 kilometers away because sources closer to bamako have dried up. it's a similar situation in and around many of africa's big cities. the disappearance of forests and degradation of the land is a huge problem. tony: how do we tackle that? fortunately, through farmer scalable method to reverse that degradation. reporter: in the 1980's, rinaudo discovered that in many places there are intact underground networks of roots struggling to grow, and that pruning shoots can help trees and bushes

flourish. world vision is now promoting the f.m.n.r. technique in 24 countries around the world. in yameriga in northern ghana, samuel bantang was among the first farmers to adopt it a decade ago. samuel: it has changed so much in my village. we used to have to drive our cattle long distances to graze. and thieves could steal them. but now they can graze nearby. reporter: but there's a lot still to do. the villagers regularly go out and work on reviving areas of degraded land, applying rinaudo's technique, and trim new shoots growing out of old stumps. farmer managed natural regeneration isn't complicated. it involves targeted pruning and protecting of new growth. still, it's very effective. these saplings will hopefully

grow into tall trees. samuel: we cut some shoots but leave the bigger ones, just one or two. what we cut away we use as firewood. reporter: the key advantage over planting new trees is that the roots are already there and reach deep into the soil. so even if it rarely rains, they can tap into the groundwater. trees can also raise the water table, release moisture into the air, and fertilize the soil when their leaves fall and decompose. as conditions improved, samuel bantang was able to increase his herd. samuel: it has helped a lot. life used to be much harder. but now things are different. we have a proper income, we can look after our families, pay for health insurance and school fees. and everybody has enough to eat. reporter: in yameriga, 82 hectares of land have so far been reforested. but large stretches still look

like a desert. degraded dryland regions may have countless intact tree root systems that could yet yield new trees, if they are properly tended. rinaudo organizes conferences across africa on f.m.n.r. also in countries that are in turmoil, such as mali. he was recently in bamako. rinaudo has devoted his life to restoring africa's forests. he says regenerating local vegetation improves the lives of millions. and giving people hope can help transform the political landscape as well in many a country. tony: it would transform the whole country, because it has that potential. people to be able to be self-sufficient on their own land, they are not going to be so interested in joining a fight somewhere else.

they have families to raise, they have aspirations on how they would like to lead their life. reporter: cities such as bamako consume vast amounts of natural resources, even as they become ever more scarce. the restoration of vegetation around cities and elsewhere can improve people's quality of life, and perhaps reduce the potential for violence and conflict. host: of the world's 68.8 million displaced persons, by far the majority, around 40 million people, are internally displaced. in colombia, years of paramilitary violence has led to 7.7 million people there suffering that fate. most have nothing to return to. their homes and livelihoods are all gone. and more recently they've been joined by 1.5 million refugees from crisis-stricken venezuela. reporter: bogota is growing fast. some 10 million people live here.

but it's the poor districts on the outskirts that are increasing most rapidly. many people displaced from their homes elsewhere in colombia have settled in soacha. the neighborhood is known to be dangerous, but it's close the city center and rents are cheap. carlos doesn't want to be recognized. a month ago he fled from gang warfare in theown of el rra. carlos: it was war, so we left so as not to get caught up in the fighting. if we hadn't left, it would have cost us our lives. reporter: the power vacuum left by the farc is now being filled by other groups. anyone who doesn't pay protection money gets murdered. carlos saw 28 people die before he decided to flee to the capital. carlos: i feel good here. i've had a lot of support from the red cross and from victim support. thank god i'm ok.

they're helping me find a job in a company. that's my plan, to find work and spend the rest of my life in bogota. reporter: the hope of a job and a home has also driven thousands of venezuelans to colombia. venezuela closed the official border crossings in february, t familiesontinue to come acss elsewhe on foot. >> there was nothing back home. nothing for my baby, nothing for us. that'so way to le. medicine, no food, noing. report: but thin won't be easy in lombia, eier. to get a work permit, you need proper i.d. almost half the venezuelans who've come here don't have that. many are exploited as day laborers. some just hang around the streets and beg for money and food. even people with a job have a hard time finding a decent place to stay. many of those who make it here sleep in so-called

"paga-diarios" -- shared rooms packed with beds. they have no rights there and could be evicted at any time. luis is a hairdresser and has a job, but he barely makes enough just to pay for his bed. luis: it's like a prison. we are like prisoners. there are three bunk beds per room. that's six people. so you have absolutely no privacy. and you can't leave any valuables there either. reporter: colombia is trying to cope with its own displaced people and many more from venezuela. the united nations refugee agency unhcr is worried that the country cannot handle the strain. jozef: in various parts of colombia, venezuelans just sleep on the streets, which makes them vulnerable to attack. there are all kinds of people. lots of women with children, pregnant women, older women, and people who need special care.

that's why the unhcr and other agencies are trying to at least offer some initial help. we want to give them a chance to build a life here in colombia as long as they can't return to venezuela. reporter: this man is one of the successful ones. he has opened a venezuelan restaurant in bogota. back home he worked in tourism, but then things became unbearable. carlos: at first i was planning to go back when the regime fell. but now i have my business here and my family. i'll have to think about it. i'll probably wait a while. rerter: the staurateurs a ro model for some other venezuelans in colombia, not just for his success, but also because he provides them aaste ofome.

host: an amazing 85% of all refugees worldwide are taken in by developing countries, regions where poverty and hunger are already key problems. industrialized nations make up just one in ten of all host countries. and one of them, japan, is notoriously tough when it comes to asylum. kim: the detainees are treated worse than animals. perhaps better than insects, but only just. reporter: tokyo, capital of one of the most homogenous societies in the world. foreigners make up only 2% of japan's population. it's also one of the countries most closed to outsiders. more than 10,000 people applied

for asylum here in 2018. but only 42 were granted a refugee status. eri ishikawa's organization says it takes care of 600 to 700 asylum seekers every year, helping them fill out applications and survive the long wait. eri: the asylum process is very strict. we see the applicants here and we think that more should be accepted. reporter: her ngo provides applicants with food, accommodation, and clothing during their wait, which averages almost 1.5 years. but its capacities are at the limit. eri: since last year, the government has made the conditions stricter for work during the waiting period, so very few people can get work and only a few get government support. reporter: the japanese government says many applicants come for economic reasons only. but documents from the

department of justice show that in recent years, only one third of all applicants were clear economic migrants. of all the industrialized countries, japan has the most rigorous interpretation of the u.n. refugee convention. applicants must be able to prove they are threatened in writing and in japanese. during the waiting period, many are at risk of becoming homeless, or if their initial application is denied, they may end up in detention pending deportation. one of the biggest detention centers is two hours outside of tokyo. kim: the building back there, that's where i was held. reporter: kim eui jung applied for asylum in 2010. decades after being involved in anti-government protests in south korea, he had reason to fear repercussions. after overstaying his visa, he spent more than 2.5 years in the center. now he is out on probation.

kim: not much gets out about the conditions in there. after six months, most people's faces turn expressionless. reporter: the inmates have been on hunger strike several times in recent years. they criticize the crowded accommodations, insufficient medical care, and the uncertainty about their status. some are confined for more than five years, although detention is onlnly meant to be temporar. one former detainee is this refugee from sri lanka. he doesn't want to give his name for fear of being recognized in his homeland. in sri lanka, he got caught between the fronts of the civil war. he fought for over 12 years to gain refugee status. >> i came here when i was 45. now i am 58, 60 now.

so, all that time is finished. i can't go back. it's like a punishment. now i don't have my children with me. i don't have my wife with me. and there is no future plan. reporter: this mountain of papers is only part of his long-running legal battle. on a stopover to canada, he was detained at the airport in japan for missing documents. it was only in january this year that he was finally recognized as a refugee. he was helped by people like kyaw kyaw soe. originally from myanmar, he is one of the few refugees who have become successful in japan. 17 years ago he opened a burmese restaurant in tokyo. kyaw: deportation is very difficult, so they do everything

they can to make life in japan hard in the hope people who sought refuge here will leave the country voluntarily. the japanese don't want these problems around them. they want to keep them far, far away. host: at the height of the eu's migration crisis in 2015, many refugees who arrived in germany from regions in turmoil, like syria, received a warm welcome. up to eight million germans volunteered to give language classes, assistance, and advice, all of which helped many young arrivals settle in. reporter: a fellow syrian has opened a supermarket in hanover. that is worth a story for the photojournalist najem al khalaf.

he documenting how pple who had tolee syria y to make lifeor themsels in germa. najem:his is okra. it is quite hard to find here. this is from syria. it tastes really good with tomaes and pepper. reporter: many germans don't engage with the migrants or refugees in their midst. najem would like to awaken an interest in syrian culture, including the food. najem: i t to show tt it is not sothing bad. on the contrary, it could be good for you, too. maybe you will find it tasty. try it. i am open-minded. i have eaten german schnitzel and stuffed cabbage. i've tried it all. reporterwhen he was 18 and

studyi politicalcience and jourlism in lenon, he wa detained crossing into syria and taken to a secret service jail where heas torture th he was gin a choice- join the army or have your family buy your freedom, which they did. after at, he knehe had to leave. najem: syria was the place where i lived and grew up, but it felt alien. it was nothe right pce for me. i just could not stay there. reporter: in 2014 he reached geany overla through t balkan he experienced so much along the way, but did not yet have the mes to recorwhat he sa on here, he arned germ, took preratory claes, and is now studying photojournalism in hanover.

he is invoed with a dia collective tre callecameo. ce a week,he team meets to scuss projects. articles. alhalaf hopehe can sooshow his latest works there. lots of the stories on the website are about the concept of identity and the many ways of thinking about it, also with respect to gender and migration. texts are in german, english, and arabic coributors fm all what wbelieve is that one plus one equals three. when people with differe pots of viewnd backgrounds

come together, that's when new, surprising, and interesting thingsmerge. reporterfor najem khalaf, meo offers a forum for expling the issues close to his heart,ree of the consaints of aore conventional publication. the latest issue of cameo's magane is devod to the tme of ankommen -- arriving. al khalaf contributed a piece with photos of young refugees o talk abo their liv and hopes. reporter: al khalaf says he feels goodn germany. but it's his profession that gives his life focus and meaning. najem: arriving is not necessarily about reaching a certain spot to live in. it can ao be about finding a place for yourself. it's not always about having a new home or a new language. it can just be a fling,

finding your place in pursuing a sport, for example. or a reaplace. the feelg of havinarrived can be very gratifyingnd othing for the soul. reporter: najem al khalaf hopes he will be allowed to stay in we're back next week. and here's a quick reminder to send us your feedback. write to global3000@dw.com, and you can find us on facebook, too, dw women. see you next time. ♪ [captioning performed by the national captioning institute,

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