摘要
为探讨黄土高原典型草原优势种植物及其根际土壤化学计量对不同降水量的响应,以宁夏固原云雾山封育20年典型草原为研究对象,利用遮雨棚技术模拟了3个不同的降水梯度(自然降水量的50%、100%和150%),测定了优势种长芒草(Stipa bungeana)、星毛委陵菜(Potentilla acaulis)和白莲蒿(Artemisia sacrorum)的地上、地下全碳(TC)、全氮(TN)、全磷(TP)含量及其根际土壤有机碳(RSOC)、全氮、全磷含量,分析了各个优势种及其根际土壤化学计量及其之间的相关性。结果表明:(1)3个优势种地上、地下总C含量、地上N含量均在50%降水下较高,星毛委陵菜地上和地下P含量及地上、地下总P含量均在100%降水处理下最高。(2)50%降水与150%降水处理相比较,长芒草地上C/N、C/P及白莲蒿、星毛委陵菜地下C/P均有显著差异(P<0.05),150%降水处理下优势种N/P显著高于50%降水处理(P<0.05)。(3)3个优势种根际土壤C、N含量高于黄土高原土壤C、N含量且150%降水处理下根际土壤C含量显著高于50%降水处理(P<0.05),增雨处理下优势种根际土壤C/N、C/P高于减雨处理,增雨处理N/P较减雨处理变化小。(4)50%降水处理下,白莲蒿和星毛委陵菜地上和地下N含量与其根际土壤C含量均呈负相关关系(P<0.05);100%降水处理下,优势种地上和地下及地上、地下总C、N、P含量与其根际土壤C、N、P之间均表现出较强的相关关系(P<0.05);150%降水处理下,优势种地下C含量与其根际土壤N含量均呈负相关关系。(5)3个优势种根际土壤N含量与地下N含量的负相关系数绝对值大于根际土壤P含量与地下P含量的相关系数绝对值。研究结果将为深入了解黄土高原典型草原生态系统物质循环及判断植被养分限制提供科学参考。
In order to explore the response of dominant species and rhizosphere soil stoichiometric of typical grassland in the Loess Plateau to different precipitation treatments,the typical grassland fenced for 20 years in Yunwu Mountain,Guyuan,Ningxia was selected as the research object,using shelter technology to simulate three different precipitation gradients(50%,100%and 150%of natural rainfall).The content of total carbon(TC),total nitrogen(TN),total phosphorus(TP),rhizosphere soil organic carbon(RSOC),total nitrogen,and total phosphorus in the aboveground and underground of the dominant species Stipa bungeana,Potentilla acaulis and Artemisia sacrorum were analyzed,The correlations between the stoichiometry of each dominant species and rhizosphere soil stoichiometry were analyzed.The results showed that(1)the above and below ground total C content and above ground N content of the three dominant species were all higher under 50%precipitation,while the above and below ground P content and total P content in Potentilla acaulis were the highest under 100%precipitation.(2)Compared with the treatment of 50%and 150%precipitation,the aboveground C/N,C/P of Stipa bungeana and the underground C/P of Potentilla acaulis and Artemisia sacrorum were significantly different(P<0.05);the N/P of dominant species under 150%precipitation treatment was significantly higher than that under 50%precipitation(P<0.05).(3)The contents of C and N in the rhizosphere soil of the three dominant species were higher than those in the Loess Plateau soil,and the content of C in the rhizosphere soil under 150%precipitation was significantly higher than that under 50%precipitation(P<0.05).Increasing precipitation treatment indicated higher C/N and C/P of the rhizosphere soil of the dominant species than decreasing precipitation treatment,but with smaller changes in N/P.(4)Under 50%precipitation treatment,there was a negative correlation between the N content and the C content in the rhizosphere soil of Artemisia sacrorum and Potentilla acaulis,both abo
作者
罗叙
王誉陶
张娟
李建平
LUO Xu;WANG Yutao;ZHANG Juan;LI Jianping(School of agriculture,Ningxia University,Yinchuan 750021,China)
出处
《生态学报》
CAS
CSCD
北大核心
2022年第3期1002-1014,共13页
Acta Ecologica Sinica
基金
宁夏重点研发计划项目(2020BEG03046)
宁夏大学草学一流学科建设项目(NXYLXK2017A01)。
关键词
黄土高原
降水梯度
建群种
根际土壤
化学计量比
the Loess Plateau
precipitation gradient
constructive species
rhizosphere soil
stoichiometric ratio
