The results of 12 years long-term applying fertilizer in slope farmland show the longterm applying fertilizer effect on yield is very obvious,effect of applying N is not obvious,effects of applying P is better,and organic matter mixed N or NP may enhance crop yield obviously. As applying fertilizer s time goes on,crOP yield and absorbing N. P are reduced step by step as lower applying-fertilizer level in a rotation period of crops, this reducing tendency may be fitted by y=α+blogt, these paramere b values b...
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