镁渣硅钾肥对含盐土壤肥力特性和油菜生长的影响

Effects of magnesium slag-based Si-K fertilizer on salty soil fertility and growth of Brassica campestris L.

镁渣硅钾肥由工业冶炼镁渣和碳酸钾(K2CO3)在高温条件下熔融反应制得。该肥料中含有K、Si、Ca、Mg等多种矿质元素,通过盆栽实验探讨施用镁渣硅钾肥对含盐土壤理化性质和植物生长的影响。结果表明,施用2 g/kg镁渣硅钾肥含盐土壤的速效钾、缓效钾和有效硅含量较对照分别提高64.80%、33.43%和18.85%;且该处理条件下油菜鲜重和叶片含钾量均有显著提高。因此镁渣硅钾肥通过提高含盐土壤的速效钾和有效硅含量,从而促进植物生长和对K元素的选择性吸收。然而过量镁渣硅钾肥的施用也会对土壤p H值和重金属含量造成显著影响。因此,针对镁渣硅钾肥的长期施用应当把握用量或者将镁渣硅钾肥进行中和改性,从而对土壤改良和肥力增强方面发挥重要作用。

Magnesium slag-based Si-K fertilizer is synthesized by magnesium slag with potassium carbonate （ K2CO3 ） at high temperature. It contains a variety of mineral components such as K, Si, Ca, Mg, etc. A pot experiment was set to explore the effects of magnesium slag-based Si-K fertilize on soil fertility and the growth of plant. Results showed that the available K, slow available K and effective Si content increased by 64.80%, 33.43% and 18.85% in the salty soil by applying 2 g/kg magnesium slag-based Si-K fertilizer, meanwhile fresh weight and leaf K content of Brassica campestris L. were significantly promoted compared to that of control. Applying magnesium slag- based Si-K fertilizer could promote the growth and K selective absorption of B. campestris L. by improving the available K content and effective Si content in the soil. However, the pH and heavy metal content of soil were influenced significantly by applying excessive magnesium slag-based Si-K fertilizer. Moderate or acidic medium should be selected to mix with magnesium slag slow-release fertilizer in the long-term fertilization, aiming to play an important role in soil amelioration and fertility enhancement.