氮添加对盐碱地湖南稷子生态化学计量及内稳性的影响OA

In order to investigate the effects of different nitrogen additions on the ecological stoiometric characteristics of carbon(C),nitrogen(N),phosphorus(P)and potassium(K)of Echinochloa frumentacea in saline-alkali land and the changes of homeostasis of Echinochloa frumentacea under different nitrogen additions,taking Echinochloa frumentacea in saline-alkali land in the north of Yinchuan area as the research object,a 2-year nitrogen addition experiment was conducted under four nitrogen addition treatments:N0,N0.5,N1,N2(nitrogen addition levels were 0,0.5,1.0,2.0 t·667m-2,in sequence).The results show that:There were significant differences in the contents of C,N,P and K between soil and Echinochloa frumentacea after different nitrogen addition(p<0.05),the contents of C,N,P and K in Echinochloa frumentacea were the highest in the first year of N0.5 treatment,and the contents of N and P in Echinochloa frumentacea were decreased in the second year;the contents of C,N,C∶P,C∶K,N∶P in Echinochloa frumentacea were positively correlated with the contents of soil N,N∶P,total salt and P(p<0.05),and the contents of P,K,C∶N in Echinochloa frumentacea were positively correlated with the contents of soil C∶N,pH value,C∶P,C∶K and C(p<0.05).The ecological stoichiometry of Echinochloa frumentacea showed significant homeostasis characteristics,and the C∶N homeostasis index was the highest.The homeostasis of Echinochloa frumentacea under different periods was as follows:the homeostasis in 2022 was higher than that in 2023.It was found that nitrogen addition could increase the nutrient content of soil and Echinochloa frumentacea,soil C and C∶N were the main factors affecting Echinochloa frumentacea,and the ability to maintain the balance with the external environment under nitrogen addition.