Abstract

Soil N2O Emission Rates and Meta-Analysis on the Tibetan Plateau: Effects of Heavy Degradation on Alpine Meadows

Author(s): Gabriel Santos

The Tibetan Plateau has severe grassland degradation. On the Tibetan Plateau and in the southeast, atmospheric nitrous oxide (N₂O) emission rates and their underlying cause are yet unknown. Gas chromatography at three river sources and meta-analysis techniques were used to examine the N₂O emission rates of substantially degraded and undamaged alpine meadow soil incubation across the Tibetan Plateau. In the southeast Tibetan Plateau, the N₂O emission rates of significantly deteriorated and control meadows were 4.29 gkg^-1h^-1 to 0.64 gkg^-1h^-1 and 3.27 g kg^-1h^-1 to 0.53 gkg^-1h^-1, respectively (p 0.01), showing an increase of 31.16% on the N₂O flow of heavy degradation. N₂O emission increased due to heavy deterioration. Rates using meta-analysis by 0.55-0.14 (95% confidence interval: 0.27-0.83). When compared to the control, high deterioration rose by around 71.6%. According to the moderator test, the Water-Filled Pore Space (WFPS) had a substantial impact on the N₂O emission rate (p 0.05). The findings of the mixed-effect model showed that WFPS, soil nitrate, and bulk soil could each account for 59.90%, 16.56%, and 15.19% of the variance in N₂O emission rates between the control and severely degraded meadows. In addition, by raising WFPS and bulk density, as well as by lowering the nitrate content of the soil, it is possible to lower the N₂O emission rates of severely degraded meadows.