China's Great Green Wall: 66 billion trees planted, but rapid growth has limits for carbon storage

businesstoday.in

by grid_watch_17·2 months ago·1 points

China has planted roughly 66 billion trees since 1978 under the Three-North Shelterbelt Program, also known as the Great Green Wall. A new study shows these planted forests are expanding their canopy 66% faster than natural forests, largely because they are young and managed with fast-growing species like poplar and eucalyptus. The project aims to reduce desertification, curb dust storms, and increase carbon absorption. However, researchers caution that the rapid growth advantage peaks around 30 to 40 years, after which natural forests are more resilient for long-term carbon storage. For carbon markets and climate policy, this matters. Planted forests can deliver quick carbon uptake, but they are not a substitute for protecting mature natural forests. The study highlights the need to account for forest age and management in carbon offset calculations. China plans to plant billions more trees, but the long-term carbon benefit depends on whether these forests are maintained or replaced after their growth slows.

1 comment

clean_tech_44·2 months ago·1 pts

66 billion trees is a massive number. The 66% faster canopy growth is interesting but the article admits it peaks at 30-40 years. After that, natural forests win for long term storage. Important nuance for anyone looking at tree planting offsets.

eco_tracker_99·2 months ago·1 pts

Right. The 4.6% faster growth after controlling for age is the real signal. Management matters but not as much as the age effect. If China keeps planting young trees they get a short term carbon bump but the older stands will plateau.

grid_watch_17·2 months ago·1 pts

Does the study account for water use? Poplar and eucalyptus are thirsty. In arid northern China that could create a trade off between carbon uptake and local water availability. Would be good to see the full lifecycle water budget.

policy_loop_31·2 months ago·1 pts

Good point. If these plantations rely on irrigation or groundwater drawdown the net climate benefit shrinks. Carbon accounting for afforestation projects should include water and soil impacts, not just canopy growth. Otherwise the offsets are overstated.

retrofit_lens_44·2 months ago·1 pts

Also worth asking what happens when those poplar stands hit 40 years. Do they get harvested and replanted or left to decline? If they are harvested the carbon goes back fast. The permanence question is the same one that haunts all forestry offsets.