Qi Le, Gao Ming, Guo Xiao-Min, Niu Hai-Dong, Li Ting, Sun Tao, Cao Qun-Ling, Tang Jia-Hao
College of Resources and Environment, Southwest University, Chongqing 400716, China.
Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, Chongqing 400715, China.
Huan Jing Ke Xue. 2018 May 8;39(5):2351-2359. doi: 10.13227/j.hjkx.201710033.
In order to explore the effects of different amounts of biochar applied in purple paddy soil on greenhouse gas (GHG) emissions, potted experiments using a static opaque chamber and gas chromatography method were used to study the regulations and influences of biochar on soil greenhouse gas emission using five treatments:no fertilizer (CK), conventional fertilization (NPK), 10 t ·hm biochar+NPK (LBC), 20 t ·hm biochar+NPK (MBC), and 40 t ·hm biochar+NPK (HBC). ① Soil CH emission flux reduced significantly with all biochar application treatments; the emission flux followed the order, from large to small, of NPK > CK > LBC > MBC > HBC. The CH emission flux of each treatment showed a single peak curve, and the peak value was mainly concentrated in the late growth stage of the paddy cropland. During the entire observation period, the emission flux of CH was between -0.05 mg ·(m ·h) and 47.34 mg ·(m ·h). The CO emission flux of each treatment was complicated and ranged from 32.95 mg ·(m ·h) to 1350.88 mg ·(m ·h). The CO emission flux of the LBC and MBC treatments showed bimodal curves, and the CO emission flux of other treatments showed single peak curves. In addition, all biochar treatments delayed the peak time of the CO emission flux. The NO emission flux of each treatment ranged from -309.39 to 895.48 μg ·(m ·h), and the NO emission flux of the LBC treatment showed a bimodal curve, while other treatments showed single peak curves. ② Compared with the CK treatment, biochar treatment can significantly reduce the cumulative emissions of CH and promote the cumulative emissions of CO and NO. The average amount of CH cumulative emissions followed the order CK > LBC > MBC > HBC, while the average amount of CO cumulative emissions followed LBC > MBC > HBC > CK, and the average amount of NO cumulative emissions followed HBC > MBC≈LBC > CK. Compared with conventional fertilization treatment, different application rates of biochar addition significantly reduced CH and CO emissions. As more biochar was added, CH and CO cumulative emissions were lower. Although the regulation of NO cumulative emissions on biochar addition was not obvious, the application of nitrogen fertilizer could promote the emission flux of NO to some extent. ③ Over the time scale of 100 years, the integrated global warming potentials (GWP) of CH and NO emission under different biochar treatment were decreased significantly, indicating that biochar combined with chemical fertilizer is an effective GHG emission reduction measure.
为探究紫色稻田土壤中施加不同量生物炭对温室气体(GHG)排放的影响,采用静态暗箱和气相色谱法进行盆栽试验,设置5个处理:不施肥(CK)、常规施肥(NPK)、10 t·hm生物炭+NPK(LBC)、20 t·hm生物炭+NPK(MBC)和40 t·hm生物炭+NPK(HBC),研究生物炭对土壤温室气体排放的调控作用及影响。①所有生物炭施加处理均使土壤CH排放通量显著降低;排放通量大小顺序为NPK>CK>LBC>MBC>HBC。各处理CH排放通量呈单峰曲线,峰值主要集中在水稻生长后期。在整个观测期内,CH排放通量在-0.05 mg·(m·h)至47.34 mg·(m·h)之间。各处理CO排放通量变化复杂,范围为32.95 mg·(m·h)至1350.88 mg·(m·h)。LBC和MBC处理的CO排放通量呈双峰曲线,其他处理呈单峰曲线。此外,所有生物炭处理均使CO排放通量峰值出现时间延迟。各处理NO排放通量范围为-309.39至895.48 μg·(m·h),LBC处理的NO排放通量呈双峰曲线,其他处理呈单峰曲线。②与CK处理相比,生物炭处理能显著降低CH的累积排放量,促进CO和NO的累积排放量。CH累积排放量平均值大小顺序为CK>LBC>MBC>HBC,CO累积排放量平均值大小顺序为LBC>MBC>HBC>CK,NO累积排放量平均值大小顺序为HBC>MBC≈LBC>CK。与常规施肥处理相比,不同生物炭添加量显著降低了CH和CO排放量。生物炭添加量越多,CH和CO累积排放量越低。虽然生物炭添加量对NO累积排放量的调控不明显,但氮肥施用在一定程度上能促进NO排放通量。③在100年时间尺度上,不同生物炭处理下CH和NO排放的综合全球变暖潜势(GWP)显著降低,表明生物炭与化肥配施是一种有效的温室气体减排措施。