中文摘要：

[目的]对马尾松根系和叶片养分（C、N、P、K、Ca、Mg）进行研究,探讨生长季和非生长季根系和叶片的化学计量学特征和养分分配特征,以及根和叶片养分的相关性。[方法]本研究分别在2014年7月和11月,利用土柱法采集根样和高枝剪采集枝条第二节上的健康叶样,然后再进行室内测试分析。[结果]表明：（1）非生长季与生长季相比,根C养分含量、C：N和N：P比值均下降,N、P、K、Ca、Mg养分含量含量均增加。（2）根C养分含量随直径增大而增加,N、P、K、Ca、Mg养分含量随直径增大而减小。（3）径级、取样时间以及两者交互作用对根系C、N、P、K、Ca、Mg养分含量和C、N、P养分化学计量比存在极显著影响（P〈0.01）,同时取样时间对粗根C、N养分含量以及C：N比无显著影响。（4）细根（〈2 mm）C和N元素含量存在极显著的负相关关系,N和P元素含量存在极显著的正相关关系,同时C：N比值和N：P比值变异分别由各自两元素含量共同决定;粗根（2 3 mm）C、N计量比值和N：P比值变异分别主要由N元素含量和P元素含量决定;（5）从地上叶到地下根,C、N、P、K养分含量呈减少趋势,Ca、Mg养分含量呈增加趋势。同时,根和叶片养分含量相关性较弱,除C、K养分之外。[结论]马尾松根系养分含量与叶片养分的关系较弱,且分别对各养分的相对需求量不同;与生长季相比,非生长季马尾松根系N、P、K、Ca、Mg含量显著增加;C、N元素和N、P元素的耦合关系只出现在细根中。

英文摘要：

[Objective]By studying C,N,P,K,Ca,Mg nutrient in root and leaf of Pinus massoniana to under-stand the stoichiometric and nutrient distribution characteristics of roots and leaves in growing or no-growing season, and the correlation between the chemical traits.[Method]In this study,in July 2014 and November 2014,the soil column method was used to collect root samples and the high branch scissors was used to collect the healthy leaves from the second sections in branches,and then the nutrients content were investigated by laboratory data a-nalysis.[Result]The results showed：（1）The root C nutrient content,C：N and C：P of P.massoniana in no-growing season showed a decreasing trend compared with that in growing season,while all the others showed a in-creasing trend.（2）The C content of roots increased with the increase of diameter,but the N,P,K,Ca,and Mg contents decreased with the increase of diameter.（3）The diameter,sampling time and root diameter ×time had＆amp;nbsp;very significant effect on nutrient content and the stoichiometry of C,N,and P nutrient,but the sampling time had little effect on coarse root C,N contents and C：N.（4）The analysis of correlation revealed that the C and N con-tents of fine root had very significant negative correlation,the N and P of fine root had very significant positive corre-lation,the variation in C：N was determined by C and N contents and in N：P by N and P contents.Meanwhile,the variation of coarse root in C：N was determined by N content and in N：P was determined by P content.（5）From leaf to root,the C,N,P,and K contents decreased,but Ca and Mg contents increased.The correlation analysis indicated that nutrient content of root and leaf had little correlation,except C and K nutrient.[Conclusion]The relationship between nutrient content of roots and leaves was weak,and the relative demand of different nutrient were different;Compared with the growing season,N,P,K,Ca,Mg content of roots in non-growing season was significantly increased;The coupling