有机无机复混肥优化运筹对稻田肥力的影响

Effects of Optimized Management of Organic-inorganic Mixed Fertilizers on Rice Soil Fertility

通过田间试验探讨了不施分蘖肥的有机无机复混肥运筹模式对机插水稻土壤总碳(TC)、总氮(TN)、微生物碳(MBC)、微生物氮(MBN)、土壤呼吸强度以及线虫特征等土壤肥力关键指标的影响。结果表明,有机无机复混肥作基肥施用,不施分蘖肥,穗肥施用一次(处理FMT)或二次(处理FMO)时水稻产量能够达到或超过单施化肥处理水平。与单施化肥相比,有机无机复混肥处理显著提高了土壤微生物量碳(MBC)和氮(MBN),MBC平均提高14.5%,MBN提高21.4%;土壤呼吸强度也得到明显提高,平均增幅31.8%,然而有机无机复混肥对土壤总碳(TC)和全氮(TN)无显著影响。有机无机复混肥处理降低了耕层(0~10 cm)土壤线虫密度,并导致食细菌线虫优势属头叶属和真头叶属相对丰度下降,食细菌线虫次优属绕线属、连胃属及植食性线虫潜根属相对丰度有所提高。应用土壤养分指标(TC、TN)、生物指标(MBC、MBN、线虫数量、土壤呼吸强度)进行主成分分析和聚类分析,结合水稻产量、肥料利用率,表明有机无机复混肥运筹是一项集培肥、增产、操作性强的施肥方式。

A filed experiment was conducted to study the effect of organic-inorganic mixed fertilizers management on soil total carbon intensity of soil showed that the fertilizer for one （TC）, total nitrogen （TN）, microbial biomass carbon （MBC）, microbial biomass nitrogen （MBN）, respiration and soil nematode characteristic in soil of rice transplanting by machine. The results organic-inorganic mixed fertilizers as base fertilizer, combined with no tillering fertilizer, or spike time （FMT） and two times （FMO）, remained or increased grain yield compared with the treatments of pure chemical fertilizer application. The contents of MBC and MBN were significantly increased by 14.5% and 21.4%, respectively, and soil respiration was raised by an average of 31.8% in the organic-inorganic mixed fertilizer managements compared with pure chemical fertilizer application. While TC and TN were little affected by the organic-inorganic mixed fertilizer managements. Furthermore, soil nematodes intensity in plough layer was decreased in FMT and FMO. In addition, the organic-inorganic mixed fertilizers decreased the relative abundances of dominant genera in bacterial feeding nematodes, named Cephalobus and Eucephalobus, but enhanced the relative abundances of Plectus and Chronogaster of suboptimized genera in bacterial feeding nematodes and Hirschmanniella Lue Goodey in plant feeding nematodes. It was proved that the organic-inorganic mixed fertilizer management was a fertilization method for the improvement of soil fertility and yield based on the results of principal component and cluster analysis.