我国主要土壤供钾能力的综合评价  

COMPREHENSIVE EVALUATION ON POTASSIUM SUPPLYING POTENTIAL OF MAIN SOILS IN CHINA

作　　者：杨振明[1] 周文佐[2] 鲍士旦[3] 史瑞和[3] 

机构地区：[1]长春农牧大学农学系,长春130062 [2]南京农业大学 [3]南京农业大学资环学院,南京210095

出　　处：《土壤学报》1999年第3期377-386,共10页Acta Pedologica Sinica

基　　金：国家自然科学基金!39470408

摘　　要：本文应用生物耗竭法并结合化学方法对我国11种主要土壤的供钾能力做了综合评价。研究表明：（1）土壤耗竭后，交换性钾的“最低值”出现的时期及绝对量大小，因土壤类型不同而异。土壤交换性钾亦存在“利用率”或“有效度”问题。“最低值”是土壤的重要供钾特性之一。（2）随着耗竭次数的增加，土壤非交换性钾在达到“最低值”后又回升，至耗竭结束，11种土壤大都接近甚至超过了耗竭前水平，认为是1mol／L热HNO3不能提取钾大量释放所致。（3）耗竭条件下，作物吸收的钾主要来自于非交换性钾，且以1mol／L热HNO3不能提取钾为主，该组分的钾仍属非交换性钾而非矿物钾。（4）2mol／L冷HNO3法提取的有效钾与作物吸钾量间的相关性最好，且该法操作简便、快速，适于水、旱田土壤钾素的测定。根据有效钾含量并结合交换性钾的“最低值”，对我国11种主要土壤的供钾能力进行了初步分级。The K supplying potential of 11 main soils in China was evaluated comprehensively with pot experiment of bio--depletion of soil potassium and chemical methods. Results were summarized as follows:The stage of the minimum value appearance and amount of soil exchangeable K varied with soil type after soil potassium depletion.The soil exchangeable K also has 'utilization ratio' or 'availability degree'. Its minimum value is one of the important characteristics of soil K supplying potential.As reaching the minimum value the nonexchangeable K increases again with the increase of the potassium depletion time, and finally, approaches or overtakes a level of pre-depletion. The results were suggested that potassium which could not be extracted by boiling in 1 mol/L HNO3 was released largely and absorbed by plants mainly. It would not be mineral K but nonexchangeable K .The closest correlation between the soil available K extracted by cold 2mol/L HNO3 and the content of K absorbed by plantS was revealed by all of the test methods. The procedure of thes method is simple and easy to operate. It is applicable tO test soil K of upland and paddy field. The K suPPlying potential of 11 main soils of China were classified preliminary based on the content of soil available K and its minimum value.

关 键 词：生物耗竭 供钾能力 有效钾 土壤 综合评价 

分 类 号：S158.3[农业科学—土壤学]