矿物质调理剂中铝的稳定性及其对酸性土壤的改良作用

通过室内土壤培养试验和模拟酸雨浸泡试验,研究了3种含铝量不同的矿物质调理剂中铝的稳定性及其对酸性土壤的改良效果。该类调理剂是利用钾长石、白云石和石灰石等合理配伍后经高温焙烧而制得,呈弱碱性,富含有效钙、镁、钾、硅等营养元素。试验结果表明,施入0.5~2 g/kg调理剂培养60 d后,土壤pH由4.98升高到5.04~5.42,交换性铝含量下降37.40%~68.90%,吸附态羟基铝含量稍有增加,但毒害性铝和活性铝总量分别降低了5.37%~9.50%和4.33%~12.08%,提高土壤中交换性钙、镁、钾和有效硅的含量。同时模拟酸雨浸泡试验中铝溶出量明显降低。该类矿物质调理剂能中和土壤酸度、缓解铝毒和增加土壤养分;调理剂中铝稳定性较高,不会对土壤铝毒产生叠加效应,可安全应用于农业生产。

Stability of Aluminum in Mineral Conditioners and Amelioration on Acid Soil

Indoor incubation and bathe equilibrium experiment were conducted to investigate the stability of aluminum in three aluminum-containing mineral conditioners and its amelioration on the acidity of soil. The mineral conditioners consist of a mixture of calcined product include potassium feldspar, dolomite and limestone powder which rich in available Ca, Mg, K, Si and other micronutrients. Results show that soil pH value rose from 4.98 to 5.04-5.42 and exchangeable Al decreased 37.40-68.90% after 60days, when the dosage was 0.5-2 g/kg. Even though the adsorbent hydroxyl aluminum increased slightly, the total toxic aluminum and available aluminum decreased 5.37 - 9.50% and 4.33 - 12.08%, respectively. Results also suggested that the exchangeable Ca, Mg, K and available Si increased. And the aluminum concentrations in the filtrate effected by simulated acid rain decreased significantly. It indicates that the mineral conditioners could neutralize the soil acidity, eliminate aluminum toxicity and improve the soil fertility. It could be used in agricultural production safely due to the high stability of aluminum in conditioners and additive of aluminum toxicity avoided.