沼液对水稻生长产量及其重金属含量的影响

沼气发酵残余液(沼液)是一种典型的优质有机物料,目前我国每年产生2亿多吨的沼液,农业生产中寻求沼液的资源化利用,对避免环境二次污染和实现畜禽养殖业的生态可持续发展具有重大的现实意义和社会意义.在田间小区试验条件下,以粳稻'亚优红一号'(Oryza saliva L)为试材,就沼液作为肥源代替化学肥料施用对其营养生长、稻谷产量及稻米中重金属含量的影响作了初步探讨.结果表明,沼液作基肥,追肥施复合肥获得的水稻产量最高,达55.9 g·plant~(-1).虽然与当地习惯施肥(基肥和追肥施复合肥)相比稻谷产量没有明显差异,但是基肥用沼液代替化学肥料,显著降低了水稻生产成本.同时,沼液作基肥,追施复合肥明显促进了水稻分蘖和生长,虽然稻米中Cu、Cd含量没有显著变化,但强化了稻米Fe、Zn营养,显著降低了Pb含量,明显提升了稻米营养品质.可是,试验结果也显示,沼液完全代替化学肥料施用对水稻生长及其产量形成是不利的.

Growth Status, Grain Yield and Heavy Metals Content of Rice(Oryza sativa L.) as Affected by Biogas Slurry Application

Biogas slurry, in agriculture, is a typical high-quality organic material. At present in China, two hundred million tons of biogas slur-ry is producing per year. So, the secondary use of biogas slurry in agriculture production is to avoid environmental pollution and to achieve the ecological sustainable development for the livestock and poultry industries, is of great practical significance and the social meanings. So the effects of biogas slurry and chemical fertilizer application on plant growth, grain yield and heavy metals content in rice seeds of the japonica 'No.1 Ya You Hong' were studied with series of field trials. The results showed that a highest rice grain yield(55.9 g·plant~(-1)) was obtained with the application of biogas slurry as basal fertilizer and the compound K_2SO_4 fertilizer(N:P_2O_5:K_2O=15:15:15) as supplemental fertilizer. The cost of rice production was obviously low for biogas slurry as basal fertilizer though no significant grain yield improvement was observed in compare to the customarily local fertilization in which both the basal and supplemental fertilizers were K_2SO_4 compound fertilizers. Meanwhile, that biogas slurry as basal fertilizer and the compound fertilizer as supplemental fertilizer could increase markedly rice plant tillers and growth, and could enhance Fe and Zn contents and reduce significantly Pb content in rice seeds, although no significant changes in Cu and Cd contents in rice seeds were obtained. Uncertainly, the experiment results also showed that only biogas slurry application on rice production could not meet the nutrition demand for rice plant growth as well as grain yield.