Great Green Walls: Hype, Myth, and Science | Annual Reviews

Matthew D. Turner, Diana K. Davis, Emily T. Yeh, Pierre Hiernaux, Emma R. Loizeaux, Emily M. Fornof, Anika M. Rice, Aaron K. Suiter. 2023. Great Green Walls: Hype, Myth, and Science. Annual Review Environment and Resources. 48:263-287. https://doi.org/10.1146/annurev-environ-112321-111102 Visions of planting walls of trees to block the expansion of the desert have long been promoted but never realized. The green wall myth persists today even though it is premised on outdated understandings of desertification. We review the history of the idea of green walls and focus on two sets of contemporary initiatives to assess their outcomes: peri-Saharan programs (Algeria's Green Dam and Great Green Wall in sub-Saharan Africa) and China's Three Norths Shelterbelt Program. This review reveals a mixed record of technical success with low rates of the establishment of monocultures of fast-growing trees vulnerable to disease. While there is evidence for reduced wind erosion in some areas, afforestat

Matthew D. Turner, Diana K. Davis, Emily T. Yeh, Pierre Hiernaux, Emma R. Loizeaux, Emily M. Fornof, Anika M. Rice, Aaron K. Suiter. 2023. Great Green Walls: Hype, Myth, and Science. Annual Review Environment and Resources. 48:263-287. https://doi.org/10.1146/annurev-environ-112321-111102 Visions of planting walls of trees to block the expansion of the desert have long been promoted but never realized. The green wall myth persists today even though it is premised on outdated understandings of desertification. We review the history of the idea of green walls and focus on two sets of contemporar