磷肥对马尾松苗木根系及针叶内氮、磷、钾生化计量特征的影响OACSTPCD

In order to comprehend the root and needle N,P and K biochemical stoichiometry characteristics of Pinus massonana,judge its nutrient restriction and utlization,this results provide technical support for fertilization management in the process of P.mas-sonana seedling cultivation.The fertilization experiment of P.massonana seedlings was carried out to analyze the effect of P fertilizer on the N,P and K mass fractions of roots and needles of one-year-old P.massonana seedlings in different seasons.The phosphorus fertilizer used calcium magnesium phosphorus fertilizer(P has an effective rate of 14%).Four levels of 0,50,100 and 200(P1,P2,P3,P4)was designed in this experment.The results showed that the content of N,P,K and their ecological stoichiometry were not significantly affected by different P application(P>0.05),but it was significantly different in different seasons(P<0.05).In the spring of the following year after fertilization,under P2 treatment N ∶ P was17.2,which was greater than 16.The roots and needles of P.massoniana in other treatments had N ∶ P<14,and the needles were treated with P fertilizer in the later stage(winter,spring of the following year)with N ∶ P higher than the CK.The ratio of N ∶ K was 2.83-29.30,both greater than 2.1,the ratio of P ∶ K was 0.68-3.82 and K ∶ P was less than 3.4.The ratio of N ∶ K of roots and needles of P.massoniana in P2 treatment was less than the CK,and the ratio of N ∶ K of needles in P3 and P4 treatments was higher than the CK.Different treatments showed that the growth process of P.massonana was limited by N and K elements,and the restriction of N and K elements was aggravated by the increase of P concentration after applying P fertilizer,especially when applying high concentration P fertilizer(P3,P4).The results of this study showed that a large amount of phosphorus(P3,P4)increased the restriction of N and K elements in the growth of P.massonana.In the cultivation of P.massonana seedlings,N,P,and K can be applied in a suitable proportion to promote seedling growth.Further research is needed on the limiting standards of N,P,and K measurement characteristics of different organs on the growth of P.massonana.