施加改良剂对重度盐碱地土壤盐碱动态及草本植物生长的影响

为了探索内陆重度盐碱地的改良新方法,实验通过聚合有机酸(聚马来酸酐和聚丙烯酸)作为降盐碱剂,采用阻盐碱层、表土成膜剂以及土壤孔隙改善剂相结合的方法,对大庆市典型内陆盐碱土进行了改良实验,并在改良后的土壤及对照样地上种植不同植物--白菜、萝卜、菠菜、豚草和长春花,评价改良效果.结果发现:(1)通过施加降盐碱剂、阻盐碱剂及土壤孔隙剂,土壤的pH值和含盐量均有明显降低,下降幅度分别为pH:0.8～1.2、含盐量:0.2%～0.5%,而且表层改良效果优于深层;(2)在上述改良基础上施用表土成膜剂,使得土壤深层与表层盐碱运动减慢,即表层盐碱更低而深层更高,有利于保持表层适宜作物生长的条件;(3)2种聚合有机物比较来看,聚马来酸酐的改良效果好于聚丙烯酸;(4)从5种植物的生长状况来看,施用上述改良剂后较对照能够明显提高作物成活以及生长,特别是改良早期5种植物均呈现明显的生长趋势,而在后期存在生长力下降的趋势,因此,在大面积改良过程中需要考虑连续多次施加降盐碱剂以增强效果.

The dynamics of soil alkali-salinity and growth status of several herbal plants after krilium addition in heavy soda saline-alkali soil in field

For probing new method of ameliorating inland saline-alkali soil, soil amendment experiment at heavy soda saline-alkali soil (Daqing City) were carried out by using krilium of HPMA(hydrolyzed poly-maleic acid) and PAA(polyacrylic acid), as well as wood tar and vinegar as alkali-depressing and alkali-preventing agents. Growth of cabbage (Brassica oleracea L.), radish(Raphanus sativus L.), spinach(Spinacia oleracea L.), ragweed(Ambrosia trifida L.) and vinca(Catharanthus roseus(L.) G. Don) and the dynamic of soil pH and salt content at 3 layers of soil were monitored. The results showed that: (1) both soil pH and salinity were significantly decreased after krilium-addition, and 0.8-1.2 decrease in pH value, and 0.2%-0.5% decrease in salt content were observed at the amendment soil comparing with untreated control. Moreover, the amendment effect at surface layer was better than the deep layer; (2) addition of film-topsoil agent reduced the transport of salinity from deep layer to the surface layer, which made the surface layer more suitable for the growth of planted species; (3) Comparison of the two polymer agents, HPMA was more effective than PAA in the effectiveness of improving saline-alkali soil; (4) From the growth status of 5 planted species, the application of the soil amendment krilium agents could significantly increase the survival and growth rate with respecting to the control. This tendency was much evident at the early phase of the soil amendment experiment (about one month), but the growth rate decreased at late phase of soil amendment. Accordingly, multi-time krilium-addition should be adopted in the large area practice of saline-alkali soil amendment for strengthening the effectiveness.