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3.微量元素不足:多年连作,蔬菜吸收土壤中的锌、硼、铁、钼等微量元素,又不施用微肥,致使土壤中的微量元素日渐减少,严重影响蔬菜的生长发育。在环境条件好的时候,蔬菜不出现缺素症状。可是在干燥时会出现缺硼和缺钼的症状,在多湿时会出现缺锰的症状。 4.土壤板结,有机质少:由于大量施用二铵、
3. Insufficient trace elements: For many years, vegetables absorb the soil of zinc, boron, iron, molybdenum and other trace elements, but not the application of trace fertilizers, resulting in soil trace elements diminishing, seriously affecting the growth and development of vegetables. When the environmental conditions are good, vegetable deficiency symptoms do not appear. However, the symptoms of boron deficiency and molybdenum deficiency appear when dry, and manganese deficiency symptoms occur when wet. 4. Soil compaction, organic matter less: due to the large number of diammonium,