东北羊草草地钾,钠含量特征的研究

东北羊草(Aneurolepidium chinense)各器官地上部分的钾含量在生长初期最高,以后逐渐降低;钠含量的变化规律与钾相似,仅在8月份有明显增高。群落地上部分的钾、钠含量高于地下部分。羊草地上部分的钾、钠积累量在生长季中的变化为单峰曲线,峰值分别出现于7月和8月,寸草苔(Carex duriuscula)和针蔺(Heleocharis acicularis)地上部分的钾、钠积累量变化与生物量相似,为双峰型。群落地下部分的钾、钠积累量明显高于地上部分,茎、叶中钾、钠积累量相近。群落的钾、钠积累量分别占根层土壤钾、钠贮量的0.25%和0.17%,占交换性及水溶性钾、钠贮量之和的2.31%和0.93%。

STUDIES ON THE CHARACTERISTICS OF K,Na CONTENT IN ANEUROLEPIDIUM CHINENSE GRASSLAND OF NORTHEAST CHINA

The characteristics of K,Na contents of the pasture-for-cutting of Aneurolepidium chi- nense grassland of Northeast China were studied.Results showed that:K concentration of every organ of the aboveground part of S.chinense was highest in early growing season, then decreased gradually as plant continues to grow.The variation of Na concentration was more or less similar to that of K,but there was a sudden increase in August.The concentrations of K,Na in the aboveground part of the community were higher than those in the under- ground part.The variations of K,Na accumulations of the aboveground part of A.chinense in the growing season were of the single-peak type,the peaks of K and Na appeared in July and August respectively.The variations of K,Na accumulations of the aboveground parts of Carex duriucula and Heleocharis acicularis were similar to those of the biomass,which were of the double-peak type.The accumulations of K and Na in the underground part of com- munity were significantly higher than those in the aboveground part;the accumulations of K, Na in leaf and stem were very close to each other.The K,Na accumulations in the commu- nity were accounted for 0.25% and 0.71% of the total reserves of the soil,2.31% and 0.93% of the soluble plus exchangeable reserves of the soil respectively.