江西省主要红壤旱地土壤钾的吸附与解吸

通过钾的等温吸附与解吸试验，研究了江西省主要红壤旱地土壤吸附钾与解吸钾之间的内在联系。旱地土壤对钾的吸附特性以Ｆｒｃｕｎｄｌｉｃｈ等温吸附方程最为吻合；黄泥土的钾吸附特征曲线是较急剧上升型，其余土壤曲线平缓，最大吸钾量的顺序依次为黄泥土＞鳝泥土＞麻砂泥土＞红砂泥上＞花岗岩黄壤土；吸附钾的解吸率在５１．７％～９６．６％之间，平均解吸率分别为５３．５％、５８．８％、８８．５％、７０．２％、９５．３％。因此施用等钾量时后者容易显效，而且优于前者，但容易发生淋溶，需钾更迫切。

Potassium Adsorption and Desorption of Main RedSoil Uplands in Jiangxi Province

Through isothermal adsorption and desorption experiments of potassium, the rela-tionship between K adsorption and desorption of red soils in Jiangxi Province was studied. The Kadsorption characteristics of red soil uplancls, however, best fit the Freundlich eduation forisothermal adsorption. The K adsorption curve for yellow mud soil was an ahrupt slope, whilethat for others a gradual one. K adsorption for sonie kinds of soils followed the following order:yellow mud soil, brown red soil, Masa soil, yellow sandy red soil, granite yellow soil. K desorp-tion rate of the soils above ranged from 51.7% to 96. 6%,and averaged 53. 5 %,58. 8% ,88 . 5 %, 7. 02%, and 95. 3%, respectively. It indicated that the soil with lower desorption ratewas more subject to being released and leaching,thus requiring additional K supply.