After returning home from college to northwest Cameroon in 2004, Tabi Joda felt a sense of profound loss. Trees that once bore fruit, provided medicine, and created shade had been cut down. Rich soils had turned to dust. “The land I used to know as a forest was no longer a forest,” he recalls. Joda, a business consultant, got to work, calling on what he’d learned in school and from local knowledge passed down over generations. He collected seeds, started a tree nursery, and launched an agroforestry initiative that enlisted local people in planting trees. They chose species that provided food and timber, supported livelihoods, and helped wildlife thrive. The effort soon spread to nearby communities. And Joda ultimately became a vocal advocate for an even bigger dream: the Great Green Wall, which aims to transform the lives of some 100 million people by planting a mosaic of trees, shrubs, and grasses along a corridor stretching some 8000 kilometers across Africa by 2030 (see map, below).

Since the African Union first launched the Great Green Wall in 2007, the initiative has struggled to make headway. Made up of local efforts across 11 countries, it has reached just 16% of its overall goal to vegetate 150 million hectares. But last month, the project—which analysts estimate will cost at least $30 billion—got a major boost: a pledge of $14 billion in funding over the next 5 years from a coalition of international development banks and governments. The money is meant to accelerate the effort to sustain livelihoods, conserve biodiversity, and combat desertification and climate change, French President Emmanuel Macron said in announcing the pledges on 11 January.

Environmental restoration and community development specialists welcomed the news. But many are also apprehensive. In recent years, research by ecologists, economists, and social scientists has shown that many forestry projects around the world have failed because they didn’t adequately address fundamental social and ecological issues. Project leaders often didn’t ask communities what kinds of trees they wanted, planted species in places where they didn’t belong, and did little to help the saplings survive. “Tree planting is often viewed as the simple act of digging a hole,” forest scientists Pedro Brancalion of the University of São Paulo, Piracicaba, and Karen Holl of the University of California, Santa Cruz, noted last year in a review of agroforestry projects in the Journal of Applied Ecology. “But this short-term, naïve view has resulted in large quantities of money being spent on … efforts that have failed almost entirely.”

It’s a problem that Joda knows well. “I have traveled the breadth of Africa and seen it everywhere,” he says. “Trees are planted, but they are not taken care of and so they never grow.” The question now, he and others say, is whether Great Green Wall projects fueled by the fresh burst of cash will heed those hard-learned lessons.

There’s little doubt that well-executed agroforestry initiatives can deliver hefty economic and ecological benefits. In the Brazilian Amazon, for example, Brancalion and other researchers have documented projects that have helped restore native plants, improve soil’s ability to store carbon, and boost the quality of drinking water. Local residents report restoration projects have even fostered tourism. In Africa, the adoption of one approach, called farmer-managed natural regeneration (FMNR), is credited with regreening a notable portion of the Sahel, the semiarid region south of the Sahara. The low-cost, low-tech restoration technique took off in Niger in the 1980s and has since spread to other nations. It relies on farmers to protect and nurture shrubs and trees that sprout from stumps, or grow from existing root systems and seeds in the soil. Over decades, FMNR has led to greater tree cover and other ecological benefits, such as higher soil carbon content, researchers have found. It has also helped increase crop yields and improve the diversity of household diets, as well as boost incomes.

READ the whole story following the link above