【摘要】 <正> “瓦碱”是一种碱化的浅色草甸土,零星分布于我国黄淮海平原的盐碱土地区。瓦碱的土表板平,呈灰白色,没有盐霜或很少盐霜。早春干旱时,土表易于板结,抑制幼苗生长,常引起缺苗现象,土壤板结严重时,甚至全部死亡,形成光板地。瓦碱上难以出苗,卽使出苗,苗也弱,分蘖少,但是出苗以后植株的生长此在附近盐土上好得多,因此羣众说:“瓦碱发老苗,不发小苗”。黄淮海平原内瓦碱的情况已有报导,但少有详细的理化研究。本文拟就瓦碱苗弱和不出苗的原因及其改良原则进行初步研究。更多还原

【Abstract】 Tile alkali soil is one kind of alkalized light meadow soils in the Northern Plain of China. It is characterized by high pH value, low concentration of soluble salts, and crusting of surface soil under drying condition. The crusting of surface soil is a serious hazard to seedling emergence, and the high pH value of the soil affects the growth of crop plants. These properties of the soil are related with the high percentage of exchangeable sodium on the colloids of the tile alkali soil. For the improvement of the colloidal properties of this soil, it is necessary to displace the excess exchangeable sodium on soil colloids with calcium （CaSO₄, organic matter and sulphur）. Breaking the crust mechanically improves the soil physical properties only temporarily.更多还原