这种肥料含有大量的硝酸盐，有助于植物生长。

This fertilizer contains a high level of ___nitrates to promote plant growth.

农民用硝酸盐处理土壤以提高肥力。

Farmers ___add nitrate to the soil to improve its fertility.

土壤中过量的硝酸盐会影响农作物生长。

Excessive ___nitrates in soil can affect crop growth.