A new study led by Prof. LI Xiaosong from the Aerospace Information Research Institute of the Chinese Academy of Sciences has evaluated land productivity dynamics (LPD) across the African Great Green Wall (GGW) between 2013 and 2022. Their findings were recently published in Scientific Reports.

The study provides a decade-long perspective on one of the world's most ambitious initiatives to combat desertification in the Sahel, aiming to assess progress toward the United Nations' Sustainable Development Goal (SDG) 15.3, focused on Land Degradation Neutrality (LDN), and identify key factors driving changes in land productivity.

Utilizing a high-resolution 30-meter LPD dataset, the researchers found that land degradation (affecting 4.93% of the GGW area) continues to outpace restoration efforts (covering 3.44% of the region). Land cover change (LCC) emerged as the primary driver of productivity gains, contributing 30.97% to improvements, while climate change (CLI) was identified as the leading cause of productivity declines, accounting for 43.51% of reductions. Specifically, human activities such as forest expansion and cropland reclamation boosted productivity, whereas forest loss and cropland abandonment accelerated degradation.

To conduct the analysis, the team employed the HiLPD-GEE tool to generate high-resolution LPD data, surpassing the resolution of traditional datasets. They then applied the Lindeman–Merenda–Gold (LMG) method to quantify the relative importance of environmental and human factors, including precipitation, temperature, CO₂ levels, nitrogen deposition, and changes in forest and cropland cover. This approach provided new insights into how these elements interact to shape land productivity across the GGW region.

"Our findings demonstrate that human intervention still holds tremendous potential to reverse land degradation," said Prof. LI. "With targeted restoration measures and climate-adaptive land management practices, the Great Green Wall can continue to transform the Sahel into a landscape of resilience and opportunity."

The study emphasizes that human-led actions, such as afforestation and land reclamation, remain key drivers of land restoration, while climate change persists as the predominant cause of degradation. It concludes by calling for integrated climate adaptation policies and sustainable land-use practices to advance SDG 15.3 and enhance ecosystem resilience across the Sahel.