华北还田夏玉米秸秆快速启动腐熟的研究

Study on the quick decomposing for summer maize straw residues

通过连续2年的室内试验和田间试验相结合的方法,探索玉米秸秆快速腐熟启动的条件。研究结果表明,土壤是秸秆腐熟的主要载体,玉米秸秆在有土壤的环境中比相同条件下没有土壤培养100 d的腐熟率高45%。厌氧条件比好氧条件下玉米秸秆腐熟提高1.1～1.3个百分点。施用37.5 kg/hm^2腐熟配方E（主效成分为纤维素菌和真菌的菌剂以及保水剂、氮素、和微生物磷钾肥的助剂）,在夏玉米秸秆还田4周和8周时腐解率为23.6%和33.1%,比不施用腐熟配方的处理高14和17.4个百分点。至下茬小麦收获期,还田玉米秸秆的腐解率为87.1%～88.4%,一年后腐解率达94%～99%。与不施用腐熟配方的处理相比,玉米秸秆腐熟配方可促使小麦的出苗率提高9.7%;有效分蘖数增加19.5%;幼苗冻死率降低1.64个百分点;小麦的株高、穗长和千粒重分别提高0.8 cm、0.25 mm和1.3 g。连续施用腐熟配方E 2年,可提高冬小麦产量5.2%～12.5%,提高玉米产量5.7%～10.1%。腐熟配方E是值得在华北平原高产区推广应用的高效腐熟配方。

A large amounts of summer maize straw residues were produced every year in North China Plain,where winter wheat and summer maize were rotated within a year,i. e. winter wheat was grown during October-June,followed by summer maize during June-September. During the recent decades,Maize cob was harvested and the straw residues was mechanically smashed and simultaneously incorporated into the soil before growing winter wheat. However,it is difficult for the maize straw residues to decompose quickly as the weather turned cold soon after late October. The straw residues adversely influenced the seedling and growth of winter wheat in fleld. By combining of laboratory and field experiments for two consecutive years,in this study,the effects of nine agents used in North China Plain and the influence facters of quickly decomposion for summer maize straw residues was examined. Besides of decomposition agents for straw residues,the results showed that soil was the main carrier for decomposing maize straw residues. The decomposing rate of maize straw residues improved 45% in soil than that of without soil,and increased 1. 1 to 1. 3 percentage points in aerobic condition than anaerobic condition on maize straw residues decomposition. When the agent E（ one of the nine agents,is the most efficient decomposer for summer maize straw residues） was applied at 37. 5 kg / hm^2,the decomposition rate was 23. 6% and 33. 1% after maize straw was returned to field 4 weeks and 8weeks,respectively,and increased by 14 and 17. 4 percentage points than that of the control,which with no decomposing agent. When agent E was added,maize straw residues were decomposed 87. 1% ～ 88. 4% at the stage of harvest wheat,and94% ～ 99% at the stage of harvest of summer maize for next season,which was almost a whole year later. Compared with the control of without decomposing agent,adding the agent E increased wheat germination rate by 9. 7%,improved the numbers of effective tiller by 19. 5%. Whereas,it decreased the death rate of seedlings resulted from frozen damage by 1. 64 percentage points. Besides,the agent E increased by 0. 8 cm,0. 25 mm and 1. 3 gram in wheat height,spike length and 1 000 grains,respectively,Therefore,adding the agent E significantly improved the yield of winter wheat by 5. 2% ～ 12. 5%,and summer maize by 5. 7% ～ 10. 1% after continuously applied to soil for two years,which was worthy for applying in North China Plain for decomposing maize straw residues.