荒漠植物叶片-土壤化学计量及植物内稳态特征

Leaf-soil stoichiometry and homeostasis characteristics of desert-related plants

为了解荒漠植物叶片碳(C)、氮(N)、磷(P)含量与土壤环境因子的关系,以新疆艾比湖保护区高、低水盐环境下14种荒漠植物群落为研究对象,测定植物叶片C、N、P含量,讨论其化学计量比、植物内稳态特征及其与土壤环境因子的关系。结果表明:(1)在不同水盐环境下,土壤有机碳(SOC)、全氮(TN)、C:N、C:P及植物叶片N、P含量存在显著差异。(2)Pearson相关性分析表明,叶片C:P与土壤电导率(EC)、SOC、C:N和C:P呈显著负相关;叶片C与土壤C:N呈显著负相关;叶片P与土壤SOC、C:N,叶片N与土壤C:N、叶片C:N与土壤TN呈显著正相关;叶片P与土壤C:P、叶片C:N与土壤N:P呈极显著正相关;且冗余分析表明,土壤C:P对艾比湖保护区植物叶片C、N、P含量及化学计量特征影响显著。(3)随土壤水盐的变化,植物叶片N、P含量及N:P的内稳态模型模拟结果不显著,内稳性指数H均大于4,属于绝对稳态,说明该研究区植物对土壤养分的适应性良好。

To understand the relationship between C,N,and P contents of the leaves of desert plants and soil environmental factors,14 desert plant communities in high and low water or salt environments in Xinjiang Ebinur Lake Nature Reserve were used as research subjects.The C,N,and P contents of the leaves were determined,their stoichiometric ratio,homeostasis characteristics,and their relationship with soil environmental factors were discussed.The results showed that:(1)There were significant differences in soil organic carbon(SOC),total N(TN),C:N,C:P,N,and P contents of leaves under varying water-salt environments.(2)Pearson correlation analysis revealed that the leaf C:P demonstrated a significant negative correlation with soil conductivity(EC),SOC,C:N,and C:P(P<0.05).Leaf C was remarkably negatively correlated with soil C:N(P<0.05).Leaf P was positively correlated with soil SOC and C:N;leaf N was positively correlated with soil C:N;and leaf C:N was positively associated with soil TN(P<0.05).Leaf P was positively correlated with soil C:P and leaf C:N with soil N:P(P<0.05).The redundancy analysis revealed that soil C:P significantly affected the C,N,and P contents and stoichiometric characteristics of the leaves of plants in the Ebinur Lake Nature Reserve.(3)The changes in soil water and salt levels,the contents of N and P in the leaves,and the results of the endostatic model simulation of N:P were insignificant.The internal stability index H was>4,which belonged to the absolute steady state,indicating that the plants in this study area demonstrated good adaptability to soil nutrients.