土壤有机质和养分（氮、磷和钾等）是土壤肥力重要的物质基础。

Soil organic matter and nutrients(e. g. nitrogen, phosphorus and potassium) play important roles in soil fertility.

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严里时有抽抽，昏迷等低血箱症状及无力、软瘫等低血钾等症状。

Yan Lishi has tics, stupor and so on low blood box symptom and incapable, weak and so on symptoms and so on low blood potassium.

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这些惰性物质包括：硅、钙、氯和钾等元素，其对生产的影响是显而易见的。

The inert deposits include silicon, calcium, Cl and K and their influence on production is obvious.

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