Nitrogen is one of three fertilizers, but a great deal use of nitrogenous fertilizer has made environmental pollution, as soon as made the descend of nitrogen efficiency of corps and enhance the cost.

 
  • 氮肥是作物的三大肥料之一,但是目前氮肥的大量施用不僅造成了環(huán)境的污染,同時(shí)導致作物對氮肥的利用效率下降,使農民的生產(chǎn)成本升高;
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