Six Years of Grassland Cultivation Promotes CO2, N2O Emissions and CH4 Uptake with Increasing N Deposition on Qinghai-Tibetan Plateau

Nitrogen (N) deposition has become an important factor of vital changes in the Qinghai-Tibetan Plateau (QTP), one key eco-regions world. To investigate how N affects fluxes GHGs (CH4, CO2, N2O) alpine grassland ecosystem, dominant ecosystems on QTP, we conducted control experiments three types grasslands, including meadow (AM), steppe (AS), and cultivated (CG) QTP. In this study, four addition gradients (0 kg Nha−1yr−1, 8 24 40 Nha−1yr−1) were set up using ammonium nitrate from 2015 to 2020 order simulate at different levels, after 6 years continuous application, greenhouse gases collected sampling plots. The results showed that simulated had no significant effect soil GHG fluxes, while type extremely fluxes. Under same conditions, CH4 absorption was higher than other two grasslands. At low levels (CK, N1), CO2 emission high (N2 N3), N2O increased more significantly it did Control cultivation should be proposed as a reliable form land-use management reduce emissions QTP era increasing deposition.