论文部分内容阅读
为探明沼液浇灌对土壤肥力及微生物的影响,揭示沼液提高土壤肥力的机制,本文采用氯仿熏蒸法、荧光定量PCR(fluorescence quantitative PCR)和PCR-DGGE法研究不同梯度沼液浇灌量(折纯N量200,150,100,50kg N·hm-2)对狼尾草(P.americanum×P.purpureum)地土壤微生物的影响。结果表明,与对照相比,沼液浇灌能显著提高土壤微生物生物量N和C,且沼液浇灌量与微生物量N和C的增量显著相关。沼液浇灌还能显著增加细菌16SrDNA基因和真菌SSU rDNA基因丰度,其中200kg N·hm-2处理含16SrDNA基因和SSU rDNA基因的微生物数量最多,沼液浇灌量与土壤中含16SrDNA基因和SSU rDNA基因的微生物数量呈显著正相关,但显著降低固氮菌nifH的基因丰度。沼液浇灌人工草地对包括细菌、真菌和固氮菌在内的土壤微生物群落多样性无显著影响,可促进含16SrDNA基因和SSU rDNA基因的微生物繁殖,但在一定程度上会抑制含nifH基因的微生物的繁殖,改变土壤含16SrDNA基因、SSU rDNA基因和nifH基因的微生物数量。
In order to explore the effect of biogas slurry irrigation on soil fertility and microorganism and to reveal the mechanism that biogas slurry can improve soil fertility, this paper studied the effects of biogas slurry with different gradient biogas slurry dosage (chloroform-fumigation, fluorescence quantitative PCR and PCR-DGGE) The effects of pure N content on soil microbe in P.americanum × P. purpureum were investigated. The results showed that compared with the control, biogas slurry irrigation significantly increased soil microbial biomass N and C, and the amount of biogas slurry irrigation was significantly correlated with microbial biomass N and C increment. Biogas slurry irrigation also significantly increased bacterial 16S rDNA gene and fungal SSU rDNA gene abundance, of which 200 kg N · hm-2 treatment of 16S rDNA gene and SSU rDNA gene microbial population, the amount of biogas slurry and soil containing 16S rDNA gene and SSU There was a significant positive correlation between the number of microbes in rDNA gene and the gene abundance of nitrogen-fixing bacteria nifH. The application of biogas slurry to artificial grassland had no significant effect on the diversity of soil microbial community including bacteria, fungi and azotobacter, which could promote the multiplication of microorganisms containing 16SrDNA gene and SSU rDNA gene, but to a certain extent, inhibit the microorganism containing nifH gene The number of microorganisms in the soil containing the 16SrDNA, SSU rDNA and nifH genes was varied.