半干旱典型草原养分添加对优势物种叶片氮磷及非结构性碳水化合物含量的影响  

Effects of nutrient addition on nitrogen,phosphorus and non-structural carbohydrates concentrations in leaves of dominant plant species in a semiarid steppe

作　　者：王雪[1,2] 雒文涛[1,2] 庾强[1] 闫彩凤[3] 徐柱文[1] 李迈和[1] 姜勇[1] 

机构地区：[1]森林与土壤生态国家重点实验室,中国科学院沈阳应用生态研究所,沈阳110164 [2]中国科学院大学,北京100049 [3]植被与环境变化国家重点实验室,中国科学院植物研究所,北京100093

出　　处：《生态学杂志》2014年第7期1795-1802,共8页Chinese Journal of Ecology

基　　金：国家自然科学基金项目(41371251,31370009);国家重点基础研究项目(2011CB403204)资助

摘　　要：在7年的养分添加(对照、低磷、低氮、低氮高磷和高氮低磷)试验基础上,测定了内蒙古半干旱典型草原优势种大针茅(Stipa grandis)和羊草(Leymus chinensis)叶片氮、磷、可溶性碳水化合物和淀粉含量。结果表明:两物种叶片氮、可溶性碳水化合物、淀粉及非结构性碳水化合物含量对养分添加有显著的响应(P<0.05),养分添加与物种有显著的交互作用(P<0.05);加氮显著增加了两物种植物叶片氮含量(P<0.05),单加N处理显著降低了两物种叶片中的淀粉含量(P<0.05),单加磷处理显著增加了羊草叶片可溶性碳水化合物含量(P<0.05),高氮低磷处理显著降低两物种叶片非结构性碳水化合物总量(P<0.05)。大针茅叶片各变量对磷添加无明显的响应,其叶片相对较高的C/N、C/P和可溶性碳水化合物/淀粉比,表明其具有相对较高的可直接利用的碳水化合物以及较高的氮、磷养分利用效率;羊草对外源养分的添加具有相对较强的竞争吸收能力。Nitrogen（N）,phosphorus（P）,soluble carbohydrates（SC）,and starch concentrations in leaves of two dominant grass species,Stipa grandis and Leymus chinensis,were examined based on a seven-year nutrient addition experiment in a semi-arid steppe in Inner Mongolia of China. The experiment included five treatments： control,low P,low N,low N ＋ high P,and high N ＋ low P. Results showed that N,P,SC,starch,and non-structural carbohydrates（NSC） concentrations in leaves of the two plant species were significantly influenced by nutrient addition（P〈0. 05）. A significant interaction effect（P〈0. 05） was observed between nutrient addition and plant species. Leaf N concentration was increased（P〈0. 05） for both plant species under the treatments with N addition; starch content was decreased（P〈0. 05） for both plants in the low N treatment; leaf SC in L. chinensis was decreased under the low P treatment; while NSC content in leaves of both species significantly decreased（P〈0. 05） with high N ＋ low P addition. No significant response was observed for all variables in S. grandis leaf to P addition. The comparatively higher leaf C /N,C /P,and SC /starch in S. grandis implied more available carbohydrates and a higher use efficiency of S. grandis in N and P nutrients,while L. chinensis exhibited a competitively stronger feature of absorbing nutrients applied.

关 键 词：草原植物 碳氮比 碳磷比 非结构性碳水化合物 养分添加 养分生理 

分 类 号：Q945[生物学—植物学]