Can biochar amendment be an ecological engineering technology to depress N2O emission in rice paddies?—A cross site field experiment from South China

摘要: Abstract Approaches to reduce N 2 O emission from crop ecosystems deserves urgent need for climate change mitigation in world agriculture. Yet, unique ecological measures depress while conserving productivity have not yet been well developed wide ranges of ecosystems. In order establish an engineering option mitigate rice ecosystems, we conducted a field experiment with biochar amendment on paddies three sites across South China 2010. This was performed 6 treatments rates 0, 20, and 40 t ha −1 without fertilization respectively. The ecosystem managed conventional production practices as seasonally man-managed wetlands, which were under flooding after seedling transplantation till panicling drainage during spiking followed by subsequent moist condition (F-D-M) harvest sites. Emission soil monitored closed chambers at 7 days interval throughout the whole growing season (WRGS) gas samples analyzed chromatograph (Agilent 7890D) equipped electron capture detector (ECD). Total O-N ranged 1.5 kg N O-N ha 1.9 kg N biochar, 0.8 kg N 1.3 kg N 0.7 kg N 0.9 kg N 20 t ha , Thus, depressed total chemical fertilizer, calculated EF reduced 0.57 ± 0.15% fertilizer only 0.36 ± 0.08% 0.22 ± 0.04% value found even much smaller than that continuously ecosystem. As pH (H O), content organic carbon all upraised significantly, improved functioning decreasing per metric ton 0.17 ± 0.02 kg N 0.10 ± 0.02 0.07 ± 0.03 kg N respectively . straw could be adopted measure enhancing fertility sustaining