应用土柱试验和HYDRUS-1 D软件模拟,研究粉煤灰充填复垦土壤可溶性钾初期迁移特征和长期浓度变化趋势。结果表明,复垦初期若有田间灌溉行为或降雨量较大,绝大部分土壤可溶性钾在10 d左右均会随着土壤水分入渗迅速迁移至下层土壤或地下水,土壤可溶性钾流失严重,粉煤灰中高富集的钾往往不能为植物利用。地下水位对复垦土壤可溶性钾质量浓度长期变化有重要影响。地下水位较高(-115 cm)时,若降雨量少、蒸发量大,上覆土壤可溶性钾浓度升高,植物养分利用机会增加,但相应地上覆土壤盐分和重金属等污染的风险也会增加。
The early transport characteristics and long-term concentration tendency of soil soluble potassi-um were studied in reclaimed soil profiles filled with fly ash, based on soil column experiment and HYDRUS-1D program. The results showed that the vast majority of soluble potassium in reclaimed soil could rapidly transport together with moisture infiltration to the underlying soil layers or groundwater with-in 10 days if there was field irrigation or heavy rainfall in the beginning of the reclamation,soil potassium loss was serious,and high enrichment potassium in fly ash could not be utilized for plants. Groundwater ta-ble in the reclamation soil profiles had a major impact on long-term process of soluble potassium concen-tration. Potassium concentration in the soil solution would increase under the condition of high groundwater table( -115 cm ) , little precipitation and much evaporation. At the same time, the plants could better make use of potassium nutrient,but the contamination risk of coversoil from salinity and heavy metals also increased correspondingly.