玉米苗期根系对黄河泥沙充填复垦不同覆土厚度的响应

Response of maize root at seedling stage to the Yellow River sediment filling reclamation with different thickness of covering soil

试验采取PVC管土柱模型方法,设置7组不同覆土厚度处理,通过测定玉米苗期的根系生物量、根冠比、根表面积、根系活力等常规性指标,以及丙二醛（MDA）、可溶性蛋白含量等抗逆性指标,研究了不同覆土厚度下玉米根系生长发育的动态变化和生长特征的内在机理。结果表明：不同覆土厚度对以上指标均具有显著性影响（P〈0.05）,随着覆土厚度的增加,根系生物量、根表面积、根系活力均显著性增加,根冠比、丙二醛含量、可溶性蛋白含量随覆土厚度的增加显著性减少。通过显著性分析和相关性分析综合各指标得出适宜玉米苗期根系生长的最优覆土厚度为60～80cm。本研究为进一步研究黄河泥沙充填复垦工程,减少复垦施工过程中的表土覆盖,节约土壤、保护耕地资源提供了一定的参考价值。

This paper adopted PVC pipe to take soil column model test,simulated the basic situation of the Yellow River sediment after filling reclamation farmland,set up seven different thickness of covering soil treatments,studied the dynamic changes of growth and development and the internal mechanism of maize root growth characteristics in different soil thickness by measuring root biomass,root-shoot ratio,root surface area,root activity,MDA,soluble protein and other indicators,and it provided certain scientific bases for reclamation thickness optimization of the Yellow River sediment filling reclamation engineering.The results indicated that：Different thickness of covering soil had a significant influence on the above indicators（P〈0.05）,and the root biomass,root surface area and root activity were significantly increased,while the root-shoot ratio,MDA and soluble protein were significantly reduced with the increase of thickness of overburden soil.Taking these factors into consideration,this test concluded that the optimal soil thickness for maize root at seedling stage was from 60cm to 80cm through significant analysis and correlation analysis and it provided certain references for further studies on the Yellow River sediment filling reclamation engineering and reducing the topsoil covered in the process of reclamation construction so as to achieve the aim of saving soil,safeguard cultivated land resource.