Potential of ecosystem carbon sinks to “neutralize” carbon emissions: A case study of Qinghai in west China and a tale of two stages

Nature-based climate solutions are playing an increasingly significant role under the long-term goal of carbon-neutrality. Carbon storage and sequestration are important service functions of the ecosystem, but these potential in neutralizing carbon emissions at provincial level is rarely evaluated. Here we take Qinghai province in northwest China to conduct a case study, as it possesses the country's best solar and wind energy resource, one of the largest ecosystem therefore great carbon sequestration potential, and has been strived to set off a carbon neutral pilot in China. We combine the carbon density observation database and the land use/cover change (LUCC) data with the InVEST model to study the spatiotemporal dynamics of the carbon stock for Qinghai's terrestrial ecosystem, which are then compared to the energy related carbon emissions. The results reveal a tale of two stages, as Qinghai transformed from being a fast growing carbon emitter during 2000–2015 to be a carbon neutral player during the 13th Five-Year Plan (2015–2020). Land management interventions can contribute to climate change mitigation through avoided emissions from ecosystem degradation, and through negative emissions via biomass growth and, soil carbon sequestration. The duel-effort of greening the power grid and enhancing the ecosystem carbon sequestration is critical in achieving Qinghai's transition. Practices like agrophotovoltaic power plant in the barren or degraded lands have demonstrated great synergies of harvesting solar energy and enhancing ecosystem carbon sequestration, and offer good example for regions alike.