Carbon storage and distribution of grassland ecosystems in Qinghai Province

Based on the soil map from the second soil census and grassland resource inventory map , the carbon storage of grassland in Qinghai province was estimated by literature collection and measured data．And it turns out, carbon storage was about 6.12 Pg, with an average carbon surface density of 18.08 kg·m⁻²．Aboveground vegetation carbon storage (including litters) was 0.0097 Pg, with an average carbon surface density of 0.03 kg·m⁻²．Carbon storage of underground vegetation was 0.0967 Pg, with average carbon surface density at 0.29 kg·m⁻²．Soil organic carbon storage was 6.01 Pg, carbon surface density at 17.76 kg·m⁻²．Soil was found to store > 54 times as much carbon as vegetation．Of the nine grassland types in the region, total carbon storage was: alpine meadow (3.64 Pg), alpine steppe (0.94 Pg), lowland meadow (0.61 Pg), warm steppe (0.35 Pg), warm desert (0.33 Pg), warm desert steppe (0.08 Pg), mountain meadow (0.08 Pg) , alpine meadow steppe (0.05 Pg) , alpine desert (0.04 Pg)．Of the five functional areas, total carbon storage was:Sanjiangyuan region, Qaidam Basin, Qilian Mountain area, Qinghai Lake basin, Hehuang Valley．The total carbon surface density in the nine different grassland types was highest in lowland meadow (57.37 kg·m⁻²), lowest in warm steppe (14.04 kg·m⁻²)．Total carbon density in five functional areas was highest in Qaidam Basin (24.41 kg·m⁻²) but lowest in Hehuang Valley (14.05 kg·m⁻²)．