A research team led by Prof. CHEN Xi from the Xinjiang Institute of Ecology and Geography of the Chinese Academy of Sciences has conducted an in-depth study on plant water use efficiency (WUE) in relation to biomass density and carbon dioxide (CO₂) balance in Central Asia's drylands from 2000 to 2023. 

Their work was published in the journal Ecological Indicators.

Plant water-use efficiency is a key factor in regulating plant ecosystem functions, directly linking the carbon and water cycles. Understanding its patterns and impact on vegetation biomass, carbon stocks, and associated fluxes is increasingly vital for addressing climate change and ecosystem sustainability.

In this study, the researchers reported an annual increase of 0.04 ± 0.66 kg/m²/year in desert plant biomass density and 0.32 ± 0.85 kg C/m²/year in carbon stocks throughout Central Asia. The total biomass density and carbon stocks of desert ecosystems in the region amount to 5.52 ± 1.19 Gt and 3.12 ± 0.88 Pg C, respectively. The actual carbon sources and sinks were identified as 0.044 Pg C and 0.218 Pg C, respectively.

One of the key findings of the study is that water use efficiency at the canopy conductance level plays a significant role in influencing carbon stocks, with a strong correlation (R² = 0.57). This highlights the importance of canopy water fluxes in regulating carbon dynamics, compared to other plant water fluxes.

The study provides valuable insights for regional strategies aimed at controlling CO₂ emissions and enhancing climate change mitigation and adaptation efforts within Central Asia and other global dryland ecosystems.