1.State Key Laboratory of Soil and Agricultural Sustainable Development, Institute of Soil Science, Chinese Academy of Sciences;2.University of Chinese Academy of Sciences;3.State Key Laboratory of Soil and Agricultural Sustainable Development, Institute of Soil Science;4.School of Resource, Environment and Chemistry, Chuxiong Normal University;5.View Sino International Limited Company
National Natural Science Foundation of China (No. 41271311); China Agriculture Research System of MOF and MARA (CARS-03)
木本泥炭和秸秆配施有快速提升土壤有机质（SOM）和作物产量的潜力，但其配施比例如何影响作物产量及其微生物机制尚不清楚。本研究通过田间试验，在施用秸秆和激发剂（RJ）基础上，比较分析了木本泥炭和秸秆三种施用比例2:1（RJM1）、3:1（RJM2）、4:1（RJM3）对土壤理化性质、细菌群落组成和水稻产量影响，并与不施用有机物料的对照（CK）进行比较；同时基于网络分析和路径分析，明确不同处理特定细菌菌群与作物产量之间潜在关系。结果表明，RJM1、RJM2、RJM3间的水稻产量差异不明显，但平均比RJ和CK显著增产16.09%和31.46%。五个处理按土壤理化性质分成显著不同的三组（P < 0.01），第一组为RJM2+RJM3，以pH、SOM、可溶性有机碳（DOC）、有效磷（AP）、速效钾（AK）含量显著升高为特征；第二组为RJ+RJM1，以硝态氮（NO3--N）和可溶性有机氮（DON）含量显著升高为特征；第三组为CK。RJM2+RJM3的SOM、DOC、AP比RJM1处理平均高29.69%、22.65%和23.95%，表示RJM2+RJM3能迅速提升土壤有机质含量。RJM2和RJM3的细菌群落组成类似，并主要受制于土壤pH、SOM、DOC的变化，但与RJM1的群落组成显著不同。RJM2+RJM3显著增加了与水稻产量正相关的盖勒氏菌（Gaiellaceae unidentified）、类诺卡氏菌（Nocardioidaceae unidentified）、土壤球菌（Terracoccus）、从毛单胞菌（Comamonadaceae unidentified）、WD2101 unidentified、鞘脂杆菌（Sphingobacteriales unidentified）的丰度，而RJM1显著增加了上述除鞘脂杆菌外的其它5个物种的丰度，表示RJM2+RJM3比RJM1刺激更多的与作物产量有正相关的优势物种。上述结果表明，RJM2+RJM3通过改善土壤pH、SOM、DOC，比RJM1刺激更多的有利于作物增产的优势物种；同时由于RJM1的SOM含量与对照没有显著变化，导致其增产的可持续性要低于RJM2+RJM3处理。综合上述结果和经济效益，推荐RJM2，即木本泥炭和秸秆的施用比例为3:1时具有同时快速提升SOM和作物产量的效果。
【Objective】The combined application of woody peat and straw has the potential to rapidly increase soil organic matter (SOM) and crop yield. However, how the application proportion of woody peat and straw affects crop yield and its microbiological mechanism remains unclear.【Method】A field experiment was designed, based on the application of straw and activator (RJ). Then, a was comparative analysis of the effects of the ratio of woody peat and straw at 2:1 (RJM1), 3:1 (RJM2), and 4:1 (RJM3) on soil physicochemical properties, bacterial community composition and rice yield was carried out, and compared with the control (CK) without any organic matter. At the same time, based on co-occurrence networks, the path analysis model was used to elucidate the potential relationship between specific bacterial flora and crop yield under different treatments. 【Result】The results showed that the rice yield of RJM1, RJM2, and RJM3 was similar, and their average yield was 16.09% and 31.46% higher than that of RJ and CK, respectively. The soil physicochemical properties of the five treatments were divided into three different groups (P < 0.01). The first group was RJM2+RJM3, which was characterized by remarkably increased pH, SOM, dissolved organic carbon (DOC), available phosphorus (AP) and available potassium (AK) contents. The second group was RJ+RJM1, which was characterized by significantly increased nitrate-nitrogen (NO3--N) and dissolved organic nitrogen (DON). The third group was CK. The average content of SOM, DOC, and AP in RJM2+RJM3 was 29.69%, 22.65%, and 23.95% higher than those of RJM1, respectively, which indicates that RJM2+RJM3 has the potential of rapidly increasing the content of soil organic matter. The bacterial community composition between RJM2 and RJM3 was similar, and was mainly influenced by soil pH, SOM and DOC, while they were significantly different from RJM1. Module 1 of key ecological clusters within the bacterial co-occurrence network had a direct and significant positive effect on rice yield, in which soil physicochemical properties indirectly affected crop yield by directly and significantly affecting module 1 properties. The improvement of yield was mainly affected by the relative abundance and community composition of module 1, while module 2 and module 3 had no significant effect on rice yield. RJM2+RJM3 significantly increased the abundance of Gaiellaceae unidentified, Nocardioidaceae unidentified, Terracoccus, Comamonadaceae unidentified, WD2101 unidentified, and Sphingobacteriales unidentified, which were positively correlated with rice yield. Also, RJM1 significantly increased the abundance of the other five species mentioned above, except Sphingobacteriales unidentified, which indicates that RJM2+RJM3 could stimulate more dominant species that were positively correlated with crop yield than RJM1. Meanwhile, the sustainability of increasing rice yield in RJM1 was lower than RJM2+RJM3 because the SOM content of RJM1 was not significantly different from that of CK and RJ. 【Conclusion】Combining the above results with economic benefits, RJM2, the application ratio of woody peat to straw 3:1, is recommended as an appropriate ratio that can rapidly improve SOM and crop yield at the same time.
ZHOU Tantan, LI Dandan, QIU Lili, XU Jisheng, ZHOU Yunpeng, TAN Jun, ZHAO Bingzi. Coupling effects of straw and woody peat on rapidly increasing soil organic matter and crop yield under different application ratios[J]. Acta Pedologica Sinica,,[In Press]