PDF(Sci-hub)
Abstract：
To evaluate long-term effect of biochar application on yield-scaled greenhouse gas emissions (YSGE) in a paddy rice cropping system, a 4-year field experiment by static chamber - gas chromatograph method was conducted in South China. Principal component analysis and terminal restriction fragment length polymorphism (T-RFLP) and real-time qPCR was used to unravel the microbial mechanisms of biochar addition. Six treatments were included: control (CK), application of 5tha(-1) biochar (BC1), application of 10tha(-1) biochar (BC2), application of 10tha(-1) biochar (BC3), rice straw return at 2400kgha(-1)(RS) and inoculated rice straw return at 2400kgha(-1)(RI). The results indicated that biochar amendment significantly decreased methane (CH4) and gross greenhouse gas (GHG) emissions. This may primarily be ascribed to the stimulated biodiversity and abundance of methanotrophic microbes, increased soil pH and improved aeration by reducing bulk density after biochar incorporation. Compared with CK, RS and RI, 26.18%, 70.02%, 66.47% of CH4 flux and 26.14%, 70.16%, 66.46% of gross GHG emissions were reduced by biochar (mean of three biochar treatments), respectively. Furthermore, biochar significantly increased harvest index of double rice production (p<0.05). In comparison with CK, RS and RI, 29.14%, 68.04%, 62.28% of YSGE was reduced by biochar, respectively, and the highest biochar addition rate (20tha(-1)) contributed most to the mitigation of GHG emissions (36.24% decrease compared to CK) and improvement of rice yield (7.65% increase compared to CK). Results of our study suggested that long-term application of biochar should be the potential way to mitigate GHGs emissions and simultaneously improve rice productivity in the paddy rice system.
摘要：
为了评估生物炭施用对水稻种植系统中产量规模温室气体排放（YSGE）的长期影响，在华南地区进行了为期4年的静态室-气相色谱现场实验。主成分分析和末端限制性片段长度多态性（T-RFLP）和实时qPCR用于揭示生物炭添加的微生物机制。包括六种治疗方法：对照（CK），5tha(-1)生物炭(BC1)的应用，10tha(-1)生物炭(BC2)的应用，10tha(-1)生物炭(BC3)的应用，稻草在2400kgha（-1）（RS）处返回，接种稻草在2400kgha（-1）（RI）处返回。结果表明，生物炭改良剂显着降低了甲烷（CH4）和温室气体（GHG）的总排放量。这可能主要归因于刺激的生物多样性和丰富的甲烷营养微生物，通过降低生物炭掺入后的容重，增加土壤pH值并改善曝气。与CK相比,RS和RI,26.18%,70.02%,CH4通量的66.47%和26.14%，70.16%，生物炭减少了66.46%的温室气体总排放量(三种生物炭处理的平均值)，分别。此外，生物炭显著提高了双稻产量的收获指数(p<0.05)。与CK相比,RS和RI,29.14%,68.04%,生物炭减少了62.28%的YSGE，分别,最高的生物炭添加率（20tha（-1））对减少温室气体排放（比CK减少36.24％）和提高水稻产量（比CK增加7.65％）贡献最大。我们的研究结果表明，生物炭的长期应用应该是减少温室气体排放并同时提高水稻生产力的潜在途径。
