Influence of Soil Drought Stress on C, N and P Stoichiometry of Tamarix Chinensis Lour. in Yellow River Delta, China

Qiangqiang Rong, Jingtao Liu, Yanpeng Cai, Zhaohua Lu, Zhenzhen Zhao, Wencong Yue, Jiangbao Xia

Taking the one-year-old T. chinensis (Tamarix chinensis Lour.) in Yellow River Delta as the study object, the variations of C, N and P stoichiometry in T. chinensis under drought stress was studied using pot experiments. The results showed that, carbon (C), nitrogen (N) and phosphorous (P) contents and their stoichiometric ratios in the root, stem and leaf of T. chinensis exhibited large variations. The variation of the root C content presented an increasing trend with the gradual intensification of the drought stress while that in leaf and stem revealed different degrees of decrease. Both N and P contents in leaf, stem and root reduced when T. chinensis was under slight drought stress and showed a trend of first increasing and later decreasing with the intensification of the stress. The values of C : N, C : P and N : P ratios represented the same variation trend when T. chinensis suffered drought stress. They increased slightly when the T. chinensis was under slight stress and showed a trend of first decreasing and later increasing with the intensification of the drought stress. Slight drought stress did not have significant influence on the growth of T. chinensis. T. chinensis took competitive and defensive life-history strategies when suffering moderate and severe drought stresses, respectively. Thus, from the standpoint of ecological stoichiometry, T. chinensis had strong drought tolerance. And a certain degree of drought stress could help for the growth of T. chinensis.