You have to watch where you step in Pag, in the very north of Ghana. Get into the wrong part of this dusty African border town and you can just come face to face with a toothy smile belonging to one of the local crocodile population.
The locals here have cultivated disturbingly close relationships with these powerful reptiles who live in the "sacred" lakes around the city. According to local legend, Pag's first leader was rescued from a crocodile while on a hunting expedition, and he decreed that none of his men would harm the animals from that day forward.
Today, locals still care for, feed and protect crocodiles. Obviously women can wash their clothes in the ponds without fear, and some brave souls even swim with the animals. Tourists attracted by the promise of "friendly" crocodiles are encouraged to pose for nasty photos while touching reptiles. It is obviously safe to approach, provided you do so from behind.
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But Pag and her crocodiles face a compelling threat from the land around her. Located on the southern tip of the semi-arid Sahel region, which stretches across the African continent, the surrounding area of Pag is covered with delicate, sandy soil that clings uncertainly to the landscape. Curved trees and stunning shrubs, perfectly adapted to cope with the periods of drought that hit the area, help to hold the soil.
But pressure from the growing population of Pag and the surrounding villages has led many trees to be cleared to provide fuel and construction materials and to make way for agricultural land. Without holding the soil together, the wind and heavy rains just sweep it away, leaving nothing for crops and wild vegetation to set its roots on. Earth is becoming a desert.
"There is a lot of degradation in our environment because there is a lot of deforestation," says Julius Avergia, founder of a local environmental group in Pag. "This has serious consequences for our future generations, so we must keep what we have."
Awaregya is now helping to coordinate efforts to maintain the desert by building a wall on all things. But this is not an ordinary wall made of brick, stone or concrete. Instead, it is shaped by trunks, branches and leaves ̵
On the day we spoke, Auvergia had already sent members of his team to three nearby villages with truckloads of seedlings so that they could join groups from the local community to plant new trees. Today, they plant acacia, mahogany, and most importantly, baobab.
Fully grown baobab trees are a sight. Their thick bulbous trunks, covered with punk rock and steep limbs, pointing to the sky, have an appearance. Baobabs – which are actually succulents – are perfectly adapted to the harsh and dry conditions of the savannah and can live to be over 2000 years old.
When the plants reach the still "young" age of about 200 years, they begin to produce a copper fruit – a green, prickly shell that hardens as it ripens on the branches of the sun to form a solid, smooth brown flake that contains completely dry, almost white pulp that has a tingling, citrusy taste. Therefore, the saplings planted by Awaregya's team are an investment for the future.
Although they seem unattractive, the people of Pag are reaping the benefits. Traditionally, ripe dried fruits are harvested by local women and cooked in sauce or mash or even candy.
But now this harvest has become far more organized. Every December until April, groups of village women dive into the bush with long sticks to gather fruit from the trees. Those who return them to their villages are sorted, cracked open, and the dried pulp is ground into a kiln and a mortar or with machines.
The resulting powder is then packaged and shipped to Europe, where it finds its way into modern smoothies, juices, ice creams and healthy foods. It is part of a $ 3.5 billion global baobab market that is expected to exceed $ 5 billion over the next five years.
This is a very special tree in Africa and has enormous cultural value. This is sacred in places – Andrew Hunt
Extracted from high levels of Vitamin C, calcium, magnesium, potassium and iron, companies like Coca-Cola, Costco, Innocent Smoothies, Juja Juice and the UK-based Yeo Valley have all products launched containing baobab. It has brought a new value to a tree that is largely thought to have little economic value in places like Ghana
"Baobab has great potential," says Andrew Hunt, founder and CEO of Aduna, a health food brand, which works with small baobab powder producers in Ghana and neighboring Burkina Faso. "It is a very special tree in Africa and has great cultural value – in places it is sacred and locals regard it as the ancestral home of spirits. But it was of little economic value and was curtailed to allow for cash crops. ”
Now with the growing demand for baobab as a supplement for healthy food, communities living in the dry landscapes where they grow up are seeing the rewards of Protecting These Unusually Looking Trees.
Aduna pays about 45 Ghanaian chedi (about $ 8 / £ 6) for a bag of 38 kg of baobab, along with an organic premium that brings the total payment to about £ 10 ($ 12), according to Hunt, many villages are under £ 40 ($ 48), so this makes a significant difference to the women who collect it. It also funded the planting of about 5,000 new baobab trees last year and expects to double this year.
The scheme helps to contribute to a far more ambitious project known as the Great Green Wall. It is trying to increase the 8,000 km barrier across the breadth of Africa to prevent the spread of the Sahara Desert. As the desert dries and dries with the drought that comes with the changing seasons, the decreasing rainfall combined with deforestation and soil degradation see it grow.
Over the past century, the Sahara Desert has expanded by more than 7,600 sq. Km per hour a year and is now 10% larger than it was in 1920. Sliding is particularly pronounced in the south, where during the same period has spread to the Sahel with more than 554,000 square kilometers. The desert now covers an area of 9.4 million square kilometers (3.6 million square miles)
This is a picture that is reproduced elsewhere. The UN estimates that 120,000 square kilometers of land are being lost to desertification worldwide each year.
"Desertification [spreads] looks more like cancer than wool or forest fire," explains Ibrahim Tiau, executive secretary of the UN Convention on Combating. Desertification (UNCCD). "The loss of the global economy is estimated at $ 1.3 billion a day due to loss of agricultural land, livestock grazing, loss of land that can be used for tourism and land used for human habitation."  Launched in 2007 by the African Union The Great Green Wall is a concerted attempt to slow down or even reverse the spread of the world's largest hot desert. Supported by the UNCCD, more than 20 countries in the Sahel now plant trees to create what they claim is the largest living "structure" in the world.
But this is by no means a glorified hedge that spans the entire continent. Around $ 8 billion (£ 6 billion) has been invested in creating new, sustainable land management practices and finding ways to improve soil quality. This includes using indigenous knowledge to find local methods of land care.
For example, in Burkina Faso, Mali and Senegal, farmers have rehabilitated the land using zai, a traditional line-building practice, i.e. strips and semicircles of stones that help retain water during dry periods and allow it to soak in solid soil. In other parts of Ghana, peasants plant ivory as a way of holding the soil together, while also using it to weave baskets.
Similar attempts for green walls around the Gobi Desert in China have limited success
But at the center of the project are the trees. Senegal itself has planted more than 12 million drought-tolerant trees in just a decade since the launch of the Great Green Wall.
"About 30 million hectares (300,000 sq. Km) of degraded land have been recovered in 20 countries," Thiaw says. "But we're only at the beginning of a long journey. I don't think this will be complete in the lives of my children or even in my own life. We have to do a lot more and we have to scale it. So far, we have only worked on small projects managed by pilot communities. "
UNDCC aims to restore 100 million hectares (1 million square km) of land in Africa by 2030. This is an ambitious goal, but one they hope will bring more food security to the Sahel by improving the soil for crops and at the same time will help extract millions of tonnes of carbon from the atmosphere.
However, success is mixed and the initiative has been criticized for slow progress. Outside Africa, similar attempts by China to put up forest barriers to contain the Gobi Desert also show limited effects . In fact, there are signs that Gobi dust storms may have increased, not decreased.
But it is here that the UNDCC hopes that a new global demand for baobab can help. While it is all very well to ask local farmers to plant, protect and nourish trees, they will always compete with the need for food and income. But if trees can help generate income on their own, then there is a compelling reason to let them grow and spread.
The UNDCC hopes to do this by involving the private sector in the Great Green Wall initiative. He hopes products such as Baobab can encourage large multinational food companies to invest in planting and harvesting schemes that are being created in places such as villages around Pag.
"Governments cannot do this alone," Tiau says. "We need to engage the private sector so that they are aware that it is profitable to recover the land." Later this year, the UNDCC will launch the Great Green Sourcing Challenge and is already talking to a number of major food corporations for inclusion.  And the potential extends beyond the Baobab. The leaves of the moringa tree are also growing as a popular food. Born in the dry sub-Himalayan regions of India, Pakistan and Afghanistan, it is suitable for growing under conditions found in many parts of the Sahel. Shea butter, popular in cosmetics and moisturizers, comes from the walnut trees that also grow in the region.
Andrew Hunt of Aduna also sees promise in grasslands traditionally grown in West Africa as fonio, a type of millet that can turn into a couscous product and could give other fashionable beans like quinoa some strong competition.
"Baobab is just one ingredient in a much bigger picture," Hunt says.
But there are some who are worried about what might happen if large multinationals and food manufacturers start to create more demand for these crops. Although it can bring valuable income and investment to an area, there is also the risk of over-exploitation or even the creation of new monocultures, similar to the huge palm oil plantations that now dominate large parts of Southeast Asia, Central America and South America.
This can only exacerbate some of the problems that lead to desertification, warns Lindsey Stringer, an expert on land and water degradation at the University of Leeds in the UK.
"While desolation itself can occur on a fairly local scale, the political and economic drivers of these decisions can work on a much larger scale, in places far from the actual sites of desertification," she says. people who are not in landlocked areas are not fully aware of what's happening in drylands as a result of their consumer behavior. "
Strategies that provide multiple benefits may be more appropriate, she says. of fruit trees – like the desert date – can help not to stabilize the soil, create shade and provide food for the local people. Granting land rights to local people can also help, as it makes them more willing to invest in sustainable land management practices.
"We need to change some of our systems, not just planting things to solve the desertification problem,
There are other approaches that can also have an impact. Solar energy, for example, can reduce the need for wood as fuel and thus the need for felling. The Moroccan city of Ouarzazate, often affected by desert storms across the Sahara, uses solar energy to treat wastewater and then uses it to irrigate surrounding land.
In Burkina Faso, microbiologists such as Forfana Barkis are inoculated. cowpea plants and acacia trees with different types of bacteria and fungi to see if they can help them become more drought-resistant and improve their growth.
Back in Pag, farmers are also trying to make biochar – charcoal used to improve soil fertility – from straw and other cultural wastes left after harvest, which can then be dumped back into the ground.
There are also benefits for women who harvest Baobab to be exported to Europe and the US. Some rural cooperatives have managed to pick up tricycles to facilitate the transport of sacks full of baobab seeds through the bush.
Women are also becoming more empowered in their communities and more involved in decisions within their own households.
"It used to be difficult for women to say that they wanted to do things because they did not have easy access to income," says Julius Auvergia. "Now they have their own income, they make decisions at the household level."
Local communities are also changing. "They no longer burn the bush and light fires," adds Awaregya. "They have created their own community laws to protect the trees."
With more trees and better soil, this can mean that the people of Pag and their crocodiles can live side by side for a long time.
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