农作物在生长发育中不仅需要从土壤中吸收氮、磷、钾等大量元素，也要吸收一些微量元素。如果土壤中缺乏某种作物必需的微量元素，就会减产，品质也会变差。如果某种微量元素含量过多，又会引起作物中毒，同样影响作物的产量和品质。那么，土壤中微量元素含量及其有效性与哪些 Crops in the growth and development not only need to absorb nitrogen, phosphorus, potassium and other large elements from the soil, but also to absorb some trace elements. If the soil lacks the trace elements that are necessary for a crop, it will cut production and the quality will deteriorate. If too much of a trace element, can cause crop poisoning, also affect the crop yield and quality. So, the soil trace elements and its effectiveness and what