大米草(Spartina anglica)自然衰退种群对N、P添加的生态响应  

Eco-physiological responses of the declining population Spartina anglica to N and P fertilizer addition

作　　者：李红丽[1] 智颖飙[1] 赵磊[1] 安树青[1] 邓自发[1] 周长芳[1] 顾舒平[1] 

机构地区：[1]南京大学生命科学院湿地生态研究所,南京210093

出　　处：《生态学报》2007年第7期2725-2732,共8页Acta Ecologica Sinica

基　　金：国家自然科学基金资助项目(30400054);国家林业局948资助项目(2005-4-13)~~

摘　　要：通过对外来植物大米草(Spartina anglica)自然衰退种群进行N肥、P肥和N-P复合肥不同梯度水平的添加,分析大米草的生长指标差异及其生理生态响应。结果表明:N、P添加后使大米草种群株高均有不同程度的增加,肥效强弱依次为N肥、P肥、N-P肥;叶片数、主根数及总生物量均显著增加(p<0.05)。除N肥外,其它处理的叶片面积和厚度与对照没有显著差异。3种肥源的添加均显著提高了大米草自然衰退种群的光合速率(p<0.05);N和N-P肥均以高浓度效果最显著,但P肥却以中浓度效果最强;光合速率分别比对照增加19.08μmol·m-2·s-1、11.23μmol·m-2·s-1和15.47μmol·m-2·s-1;14d淡水淹没后,肥源添加使大米草自然衰退种群的SOD和POD酶活性增强;中浓度N和中浓度P添加使SOD活性增加最显著,分别比对照增加320.74unit·g-1和134.54unit·g-1;高浓度N和高浓度N-P肥添加使POD酶活性最显著增加。N肥添加可以显著改善大米草自然衰退种群生长生理特性,可以推断大米草种群的衰退与我国海岸带土壤营养中N素营养的限制有一定的相关性。N, P and combined N-P were added to a declining population of Spartina anglica Hubbard in coastal China. Some growth parameters and eco-physiological responses of S. anglica to different treatments were documented. The fertilizer addition had a highly significant effect on the dynamics of its height-growth, the number of leaves, the number of roots and total biomass; however, only N addition had significant effect on leaf area and the leaf thickness in all fertilizer addition. For the dynamics of its height-growth, the effect of N was most apparent; the effect of N-P was not greater than those of N and P separately. The fertilizer addition treatments all enhanced the photosynthesis rate. For the three series of fertilization treatments, the highest N, highest N-P, and medium P yielded the highest photosynthetic rates. The rates were higher by 19.08 μmol·m^-·s^-1, 15.47 μmol·m^-1·s^-1 and 11.23 μmol·m^-1 ·s^-1than that of CK respectively. Afte freshwatar stresss for 14 davs. treatments made the activity of SOD and POD increase. Effects of medium N and P was significant for SOD activity, However, POD activity of high N and N-P were distinctly higher. In a word, fertilizer addition improved the growth of declining populations of S. anglica, which indicated the decline of S. anglica was correlated with the nutriment deficiency in soil, especially lack of N.

关 键 词：大米草 自然衰退 营养限制 高生长 生理生态 

分 类 号：Q948[生物学—植物学]