不同种源中间锦鸡儿碳氮磷化学计量特征研究

摘要

To understand the response and adaptation of carbon(C),nitrogen(N)and phosphorus(P)stoichimetry to environmental changes,we conducted a provenance experiment on C.liouana,the dominant shrub species in the Mu Us Sandland of Northern China.We collected seeds from nine provenances and seedlings were cultivated under uniform condition,measuring the concentrations of C,N and P of different organs of C.liouana originated from nine provenances.The results showed that: (1) there were significant differences in C,N and P concentrations among provenances for different organs,with C concentrations of roots,stems and leaves ranging from 361.12 to 426.30 mg·g-1,from 412.32 to 463.13 mg·g-1,from 419.21 to 478.94 mg·g-1,respectively,with N concentrations ranging from 20.52 to 33.67 mg·g-1,from 15.77 to 23.92 mg·g-1,from 27.60 to 36.44 mg·g-1 and with P concentrations from 1.52 to 3.73 mg·g-1,from 1.24 to 2.14 mg·g-1,from 1.44 to 2.38 mg·g-1,respectively.The C/N,C/P and N/P were also significantly differed among provenances for different organs.(2) GLM analysis revealed that relative to the strong effect of organs on C,N and C/N,the provenances appeared to have greater effects on P,C/P and N/P.(3) There were also significant correlations between N and C/N,P and C/P.The N/P was significantly correlated with both N and P.Overall,these results suggest that adaptation of C.liouana to different environments has led to its genetic differentiation in stoichiometric traits,and differences in C,N and P stoichiometry among different organs probably suggest that C.liouana has evolved a series of strategies in nutrient utilization.%中间锦鸡儿(Caragana liouana)是中国毛乌素沙地的主要灌木建群种,在其主要分布区采集9个不同地理种源的种子,栽种至同质园,并测定不同器官(根、茎、叶)碳(C)、氮(N)、磷(P)含量,比较种源和器官间碳氮磷化学计量特征的差异及元素之间的相关性.结果显示:(1)不同种源中间锦鸡儿根、茎、叶的C含量差异显著,分别为361.12~426.30 mg·g-1、412.32~463.13 mg·g-1、419.21~478.94 mg·g-1;N含量种源间差异显著,分别为20.52~33.67 mg·g-1、15.77~23.92 mg·g-1、27.60~36.44 mg·g-1;P含量种源间差异显著,分别为1.52~3.73 mg·g-1、1.24~2.14 mg·g-1、1.44~2.38 mg·g-1;不同器官的C/N、C/P、N/P也表现出种源间显著差异.(2)种源和器官对中间锦鸡儿碳氮磷化学计量特征的影响程度存在差异,种源对P、C/P、N/P影响较大,器官对C、N、C/N影响较大.(3)相关性分析表明,N、P分别对C/N和C/P的变异起主导作用,并共同影响N/P的变异.研究表明,中间锦鸡儿的碳氮磷化学计量特征在长期的适应进化过程中已产生遗传分化,并形成了自身的养分利用策略.