宁夏典型草原区不同退耕年限草地植物群落及优势植物C、N、P化学计量特征  

C, N, and P stoichiometric characteristics of plant communities and dominant plants from different vegetation restoration periods in typical Ningxia grasslands

作　　者：陆颖 王保林 沈艳[1,2] LU Ying;WANG Baolin;SHEN Yan(College of Agriculture,Ningxia University,Yinchuan 750021,Ningxia,China;Key Laboratory of Restoration and Rehabilitation of Degraded Eco-system in Northwestern China,Ningxia University,Yinchuan 750021,Ningxia,China)

机构地区：[1]宁夏大学农学院,宁夏银川750021 [2]西北土地退化与生态恢复省部共建国家重点实验室培育基地,宁夏银川750021

出　　处：《草业科学》2019年第5期1200-1206,共7页Pratacultural Science

基　　金：国家自然科学基金(31360582;31460632)

摘　　要：植物C、N、P化学计量特征和草原生态系统功能的正常发挥有直接关系。为了研究宁夏典型草原区不同退耕年限草地植物群落和优势植物化学计量特征的变化规律,以宁夏南部典型草原区不同退耕年限(21、16、11、9、5、3、2年)草地为研究对象,分别对披碱草(Elymus dahuricus)、长芒草(Stipa bungeana)、赖草(Leymus secalinus)、早熟禾(Poa annu)等优势植物及植物群落C、N、P化学计量特征进行分析。结果表明,随着退耕年限增加,植物群落地上部C含量总体呈现下降趋势,全N含量大体呈先减少后增加趋势,全P含量无明显变化规律,C∶N、C∶P、N∶P整体表现为21年退耕地最大,9年退耕地最小;优势植物C含量表现为地上部大于地下部,全P含量表现为地下部大于地上部;植物群落N∶P值和全N含量呈正相关关系,优势植物N∶P值和全N含量呈正相关关系,且N∶P均小于14。典型草原区植物群落和优势植物在整体水平上均受到N素的限制,植物生态化学计量特征对草原的退化和恢复具有指示作用。Plant C,N,and P stoichiometric characteristics are directly related to the normal functioning of grassland ecosystems.To determine changes in the stoichiometric characteristics of plant communities and dominant plants from different vegetation restoration periods in the Ningxia typical steppe area,grassland from different restoration periods(21,16,11,9,5,3,and 2 years)in southern Ningxia were analysed and the C,N,and P stoichiometric characteristics of plant communities and dominant plants,including Elymus dahuricus,Stipa bungeana,Leymus secalinus,and Poa annua were examined.The results showed that with an increase in the restoration period,the C content of the aboveground part of the plant communities had an overall upward trend,total N content fluctuated,and total P content decreased.C∶N,C∶P,and N∶P were the highest in 1995 and the lowest in 2007.The C content of the aboveground part of the dominant plants was higher than that of the underground part,whereas the total P content of the underground part was larger than that of the aboveground part.There was a positive correlation between N:P and total N of plant communities N∶P,total N of dominant plants showed a positive correlation,and N∶P was less than 14.The plant communities and dominant plants in the Ningxia typical steppe area were restricted by N content,and the characteristics of the plant eco-stoichiometry showed some indication of the degradation and restoration of grasslands.

关 键 词：宁夏典型草原区 退耕草地 植物群落 优势植物 碳、氮、磷生态化学计量特征 

分 类 号：Q946.91[生物学—植物学]