安徽烟区土壤供钾特性的研究

A STUDY ON THE CHARACTERISTICS OF POTASSIUM SUPPLY FROM TOBACCO-GROWN SOILS IN ANHUI PROVINCE

用常规分析、钾的容量强度(Q/I)关系和电超滤(EUF)等法研究了安徽烟区黄红壤、黄棕壤和砂姜黑土的供钾特性。结果表明:粘粒矿物以高岭石、水云母为主的黄红壤有较高的供钾强度及速效钾数量,但土壤的供钾潜力及钾位缓冲容量PBC^k较低,固钾能力弱。粘粒矿物以水云母、蒙脱石为主的黄棕壤及以蒙脱石、水云母为主的砂姜黑土的供钾特性与黄红壤相反,其中砂姜黑土除固钾能力高于黄棕壤外,其他供钾指标略低于黄棕壤。土壤的供钾特性对烟草的吸钾量及钾肥肥效有直接影响。

This paper deal with the characteristics of potassium supply in yelloish red earth, yellow-brown earth and Sajong black soil in Anhui tobaccogrown district, Soils were studied with conventional test methods, electroultrafitration (EUF), and quantity/intensity (Q/I) relationship curve. Results show that the intensity and quantity of potassium were greater in yellowish red earth with kaolinite and hydrous micas as dominant clay minerals than those in Sajong black soil with clay minerals of mainly montmorillonoids and hydrous micas and than those in yellow-brown earth chiefly containing hydrous micas and montmorillonoids, but yellow red earth appeared lower in potassium supply potential buffering capacity(PBC^k)and K fixation than Sajong black soil and yellow-brown earth. Therefore, it is suggested, for tobaccogrowing practice of short term, K contents of flue-cured tobacco grown on yellowish red earth may be higher than those on Sajong black soil and yellow-brow earth, while for long-term tobacco-growing practice Sajong black soil and yellow-brown earth can keep higher K concentration in soil solution than yellowish red earth, particularly at later growth stage.