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近五年来关于土壤中锌的有效牲讨论已初步明确了以下几个问题: 1.锌在土壤中主要以吸附形态存在,它们在土壤中的活度符合Langmuir方程式。2.pH是影响土壤有效锌的重要因子。一般来说pH值为5以上时,随pH的上升,有效锌急骤下降。作物缺锌常发生在pH值为6.5～8以上的土壤中。3.土壤氧化还原电位与有效锌含量成正相关,因而水稻缺锌常发生在低洼地或排水不良的土壤中。4.温度明显地影响作物对土壤中锌的吸收,作物缺锌常同低温相伴随。光照的质和量也影响作物对锌的吸收。5.磷锌拮抗并非规律,只有当P/Zn比值超过某一数值对,拮抗作用才会发生,在一定条件下磷锌之间互有促进作用。6.氮、钾、铁、锰、铜等也都影响作物对锌的吸收。7.不同作物品种的根系对土壤中锌的利用能力有显著的差别,因此选育高产又抗缺锌的品种,可能是解决作物缺锌最经济的途径。
The past five years on the effective discussion of zinc in the soil has initially identified the following questions: 1. Zinc in the soil mainly in the form of adsorption, their activity in the soil in line with the Langmuir equation. 2.pH is an important factor affecting soil available zinc. In general, when the pH value is 5 or more, the effective zinc rapidly decreases with the increase of pH. Zinc deficiency in crops often occurs in soils with pH values above 6.5-8. Soil redox potential is positively correlated with available zinc content, so zinc deficiency often occurs in lowland or poorly drained soils. 4. Temperature significantly affects the crop’s absorption of zinc in soils, and zinc deficiency in crops is often accompanied by low temperatures. The quality and amount of light also affects the crop’s absorption of zinc. 5. Phosphorus and zinc antagonism is not regular, and only when the P / Zn ratio exceeds a certain number of pairs, the antagonism will occur, under certain conditions, each of the promotion of the role of phosphorus and zinc. 6. Nitrogen, potassium, iron, manganese, copper and other crops also affect the absorption of zinc. 7. Roots of different crop varieties have significant differences in zinc utilization ability in soil, so breeding high yield and zinc-deficient varieties may be the most economical way to solve the problem of zinc deficiency in crops.