Changes in soil CO2 and N2O emissions in response to urea and biochar-based urea in a subtropical Moso bamboo forest

作者：Shaobo Zhang, Jiashu Zhou, Ji Chen, Tida Ge, Yanjiang Cai, Bing Yu, Hailong Wang, Jason C. White, Yongfu Li · 发表于：Soil and Tillage Research · 年份：2023 · DOI：10.1016/j.still.2022.105625 · 被引用次数：25 · 研究领域：Soil Carbon and Nitrogen Dynamics、Soil and Unsaturated Flow、Clay minerals and soil interactions

The application of biochar-based fertilizers is an effective strategy for enhancing plant growth and soil organic carbon stocks; however, the impacts of such practices on soil CO 2 and N 2 O emissions and associated mechanisms in subtropical forests are poorly understood. A two-year field trial was conducted to determine effects of urea and biochar-based urea on variations in soil CO 2 and N 2 O emissions, as well as various soil environmental factors in a subtropical Moso bamboo forest. Five treatments were established: a control (without fertilization), urea with low and high application rates (100 and 300 kg N ha −1 , LU and HU), and biochar-based urea with low and high application rates (100 and 300 kg N ha −1 , LBU and HBU). The soil CO 2 emissions were increased by LU, HU, and HBU treatments during the first year compared to controls ( P < 0.05). However, this stimulatory response was observed only under the HU treatment during the second year. The soil N 2 O emissions increased under the LU and HU treatments during the first year but were decreased under HBU ( P < 0.05); during the second year, only HU had a stimulatory effect. Importantly, the soil CO 2 emissions and their Q 10 values under the biochar-based urea treatment were lower than those with urea ( P < 0.05). The application of urea increased contents of NH 4 + -N, NO 3 − -N, water soluble organic C/N (WSOC/WSON), as well as activities of invertase , β-glucosidase, urease , and protease ( P < 0.05). In compari...