Over a period of more than 2,500 years, China constructed and maintained its Great Wall to repel invasions and control its borders. Despite stretching over more than 21,000 km, this wall was often unsuccessful in holding back northern attackers.
More recently, China has built a more successful wall, a 'Green Wall', 436 km long, that is holding back thousands of hectares of sand dunes from within the second largest sand desert in the world, the Taklamakan Desert. Comprising a dense plantation of irrigated, indigenous, desert plant species adjacent to the highway that cuts through the centre of the desert, the Green Wall protects the road infrastructure from being covered in sand.
The air temperature of the Taklamakan Desert has increased as a result of climate change. It is likely that sands will become increasingly mobile as top soils become drier as a result of warming. The Green Wall is a prime example of the Ecosystem-based Adaptation (EbA) approach being undertaken by China. This EbA good practice and the related technologies can be shared and transferred to Africa, in particular in support to the 'Great Green Wall of the Sahara and the Sahel' initiative.
Key lessons
- The Green Wall of the Taklamakan Desert shows how human ingenuity and science can overcome tremendous environmental barriers to develop new, green ecosystems that provide adaptation services such as protection of infrastructure, as well as an increase of biodiversity.
- EbA is cost effective: the total cost of investment on the Green Wall is significantly lower than the estimated total cost of removing sand from the road.
- Long-term ecological research is of fundamental importance for EbA implementation.
- Applied research should be conducted in collaboration with both the private and public sectors to trigger appropriate up-scaling of EbA interventions.
- EbA good practices and technologies can be shared and transferred to Africa, in particular in support to its Great Green Wall of the Sahara and the Sahel.
