营养元素添加对青藏高原亚高寒草甸物种多度分布格局的影响  

Effects of nutrient additions on species abundance distribution in an alpine meadow in the Qinghai-Tibetan Plateau, China

作　　者：孙小妹[1] 肖美玲[1] 师瑞玲 韩非[1] 王刚[1] 

机构地区：[1]兰州大学生命科学学院,兰州730000

出　　处：《兰州大学学报（自然科学版）》2014年第6期853-859,共7页Journal of Lanzhou University(Natural Sciences)

基　　金：国家自然科学基金项目(31270472);国家公益性行业科研专项(201203006)

摘　　要：以青藏高原亚高寒草甸为研究对象,基于N,P,N+P耦合营养元素添加的控制实验,研究了群落内全部物种、常见种和稀有种的物种多度分布格局以及物种丰富度对N,P,N+P耦合营养元素添加的响应规律,并选取对数正态模型、幂分割模型、几何级数模型、Zipf模型以及中性模型对物种多度数据进行拟合.结果表明:1)P添加对物种丰富度的影响不显著,全部物种、常见种与稀有种的物种多度分布曲线的陡缓程度基本相同.随N,N+P耦合添加量的增大,全部物种与常见种的物种多度分布曲线都越来越陡峭,物种丰富度也都显著下降,表明在青藏高原亚高寒草甸N,N+P耦合添加会导致物种多样性的降低.2)比较CK,N15,P15,N15P15的物种多度分布曲线发现N+P耦合处理的物种多度分布曲线的陡峭度较CK,N15,P15处理的要陡,表明N+P耦合对物种多度分布格局的影响效应要强于单独的N,P的.3)分析施肥对物种多度分布模式的影响发现,全部物种的多度分布符合统计模型的对数正态模型以及基于生态位理论的幂分割模型、几何级数模型与Zipf模型.常见种的多度分布符合几何级数模型与Zipf模型,而稀有种在同时符合这两种基于生态位分化的模型外,呈现出符合中性模型的趋势.说明多种不同模型可以拟合同一生境的物种多度分布,常见种和稀有种通过不同的响应方式共同维持着亚高寒草甸生态系统的物种多样性.Based on N, P, N＋P addition experiment was carried out at the alpine meadow community. We examined the species abundance distributions （SADs） of entire species, common species and rare species in N, P, N＋P addition treatments, and the effects of nutrient addition on species richness. We tested whether the SADs fitted the normal distribution, power fraction, geometric seriers, Zipf model and Hubbel model. Our results showed that P addition had insignificant effect on species richness, and the slope of SADs for entire species, common species and rare species to P addition was approximate. The slope of SADs to N addition and combined N＋P was increasing steep and the species richness significantly decreased with the increasing N and N＋P addition rates. Compared the slope of SADs in the treatment of CK, N15, P15 and N15P15, the slope of SADs in N＋P addition treatment was the steepest. We observed the normal distribution, power fraction, geometric seriers and Zipf model well fitted for entire species abundance. The common species were better fitted by geometric seriers and Zipf model. The rare species were better fitted by geometric seriers, Zipf model and Hubbel model. Our findings indicate that a variety of different models can explain the SADs in the same life habitats, common species and rare species take different strategies to maintain the species diversity in alpine meadow.

关 键 词：物种多度分布 营养元素 常见种 稀有种 物种丰富度 亚高寒草甸 

分 类 号：Q142[生物学—生态学]