中文摘要：

大豆、春小麦均能有效地活化利用白云母、钾长石中的结构性钾，结构钾释放量为19．53mg kg^-1～45．46mg kg^-1。春小麦和大豆根系分泌的有机酸主要为草酸、酒石酸和柠檬酸，其次为乳酸、乙酸和苹果酸。草酸溶液酸性较强，络合能力也强，其活化钾的能力最强。苹果酸、酒石酸、柠檬酸、乙酸和乳酸亦可有效地促进白云母和钾长石的分解，但活化土壤钾的能力比较低。低分子量有机酸作用下矿物钾的释放是酸性水解和络合溶解双重作用的结果。草酸、酒石酸、柠檬酸是影响大豆、春小麦吸收利用矿物钾的主要低分子量有机酸。

英文摘要：

Mobilization of mineral potassium by plants was investigated. The amount of mineral potassium releasing from muscovite and feldspar ranged from 19.53mg kg^-1 to 45.46mg kg^-1. we fould that spring wheat and soybean roots could excrete more oxalic acid, tartaric acid and citric acid than the other organic acids. Oxalic acid had highest mobilization effect than the other organic acid and inorganic acid solution utilized. Low - molecular - weigh organic acids could have destructive effect on the k - bearing minerals, but their mobilization effect on K release was not significant. In conclusion, oxalic acid, tartaric acid and citric acid are the dominative organic acids in spring wheat and soybean root exudation which determines mineral potassium releasing.