Abstract：Different nitrogen (N),Phosphorus (P),potassium (Potassium,K) fertilization combinations and mixed sowing ratios of grasses were used to study the effects of the nutrition contents and ecological stoichiometric characteristics on grass with alfalfa (Medicago sativa) + smooth brome (Bromus inermis) grassland. The results showed that effects of fertilization on the first cutting N,P,K contents and C:P rate,the second cutting P,K contents and C:P,N:P rate,and the third cutting C,P,K contents,C:N,C:P,N:P rate in grass were extremely significant (P<0.01). The C,P,K contents and C:P,N:P rate of the first,the second and the third cutting N,P,K contents and C:P,C:N,N:P in alfalfa were effected extremely significantly by fertilization (P<0.01). The P content and C:P of the first cutting and C content of the second cutting and C:N,N:P of the third cuing in grass was affected extremely significantly by legume-grass mixed sowing ratios (P<0.01).The interaction of fertilization and mixed sowing ratio had a very significant effect on the C content of each cutting and the first,second cutting P content and C:P rate in grass and the P content and C:P rate of each cutting and the first and second cutting N:P in alfalfa. The N:P rate of grasses ranged from 3.53 to 7.60 and the alfalfa ranged from 8.37 to 12.32. It was indicated that the growth of grass was mainly affected by nitrogen,while the growth of alfalfa is affected by both nitrogen and phosphorus.
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2020, Vol. 28 
