有机肥替代化肥对小白菜品质和生态化学计量学特征以及土壤综合肥力的影响

Responses of the Quality and Ecological Stoichiometry Characteristics in Pak-Choi Shoot and Integrated Fertility of Vegetable Soil to Substituting Manures for Chemical Fertilizers

土壤肥力质量高低直接影响作物品质,生态化学计量学方法既可为维持农田较高生产力提供理论指导,又可为研究作物体内元素组成及其相互关系提供新思路。采用盆栽试验方法,探索不同畜禽粪便有机肥替代部分化肥对小白菜品质与生态化学计量学特征和菜地土壤综合肥力及其相互关系的影响。结果表明,等量氮磷钾养分条件下,与单施化肥相比,猪粪沼渣有机肥替代部分化肥显著增加小白菜地上部全磷、可溶性糖、可溶性蛋白和Vc含量7.73%~48.0%,提高土壤pH、有机质、碱解氮、有效磷含量10.6%~124.8%,继而显著提升土壤综合肥力指数(IFI)15.0%;鸡粪有机肥替代部分化肥显著增加小白菜地上部全磷和可溶性糖含量以及土壤有机质含量6.42%~11.4%,降低土壤全氮、碱解氮和速效钾含量8.79%~27.3%,但其对土壤有效磷含量和IFI影响不显著;猪粪沼渣和鸡粪有机肥替代部分化肥显著提高其小白菜地上部C/N化学计量比14.0%和22.7%,降低其地上部硝酸盐含量、N/P与C/P化学计量比12.7%~71.0%和10.7%~75.8%。另外,小白菜地上部全碳含量与C/N和C/P化学计量比显著正相关;全氮含量与C/N和C/P化学计量比显著或极显著负相关,而与N/P化学计量比和IFI极显著正相关;全磷含量与C/P化学计量比和IFI极显著负相关;可溶性糖、可溶性蛋白和Vc含量与地上部全氮、全磷含量以及IFI均呈显著或极显著正相关关系,与C/N和C/P化学计量比呈显著或极显著负相关关系;小白菜地上部硝酸盐含量与其全氮含量和N/P化学计量比呈极显著正相关关系,与C/N化学计量比呈显著负相关关系。因此,施用猪粪沼渣或鸡粪有机肥替代部分化肥可有效提升菜地综合土壤肥力和小白菜品质,为畜禽粪便高效资源化利用和设施蔬菜化肥减施提质及其绿色可持续发展提供科学参考与依据。

Soil fertility directly affects the quality of crops.The theoretical methods of ecological stoichiometry can not only theoretically provide guidance for maintaining high productivity of farmland,but also establish a new way for studying the element composition and its coupling relationship in crops.A pot experiment was carried out to investigate the effects of different livestock and poultry manures substituting for chemical fertilizers(CF)on the quality and ecological stoichiometry characteristics of pak-choi shoot as well as the integrated soil fertility of reddish vegetable field and its correlation.The results showed that under the condition of equally fertilizing N,P and K nutrients,compared to applying CF solely,partly substitution of biogas residue manure(BG)for CF significantly increased the contents of total P,soluble sugar,soluble protein and Vc by 7.73%~48.0% in pak-choi shoot,by 10.6%~124.8% in contents of soil organic matter(SOM),available N,available P and pH which resulted in an increase of the integrated fertility index(IFI)of vegetable soil by 15.0%.Meanwhile,the measurement of partly substituting chicken manure(CM)for CF increased the total P and soluble protein contents in pak-choi shoot as well as the SOM content of vegetable field by 6.42%~11.4%,however,the contents of total N,available N and available K decreased by 8.79%~27.3%.Moreover,partly substitution of the BG and CM for CF remarkably increased the C/N ratio by 14.0 % and 22.7%,while decreased the NO3- content and the N/P,C/P ratios by 12.7%~71.0% and 10.7%~75.8% in pak-choi shoot respectively.Furthermore,it was observed that the total C content in pak-choi shoot was markedly positively correlated with the C/N and C/P ratios.The total N content of pak-choi shoot,was observably negatively correlated with the C/N and C/P ratios,which was remarkably positively correlated with the N/P ratio and IFI of vegetable soil.The total P content was significantly negatively correlated with the C/P ratio and IFI.The contents of soluble sugar,soluble protein and Vc were strikingly positively correlated with the contents of total N and total P in pak-choi shoot as well as the IFI of vegetable soil,while they were notably negatively correlated with the C/N and C/P ratios in pak-choi shoot.In addition,the NO3- content was noticeably positively correlated with the N/P ratio and total N content while evidently negatively correlated with the C/N ratio in pak-choi shoot.Hence,it could be concluded that partly substituting biogas residue or chicken manure for chemical fertilizer would not only improve the quality of pak-choi shoot and the integrated soil fertility of vegetable field,but also scientifically afford references and theoretical basis for reducing chemical N,P and K fertilizers,and then improving the quality and sustainable production of greenhouse vegetable.