β多样性(Beta Diversity)探究不同生境群落组成差异或沿环境梯度的更替特征,即生境间的多样性(between-habitat diversity)。β多样性越大代表群落间的共有物种越少且物种组成差异越大,往往用来指示不同生境的物种隔离程度,且与α多样性共同构成了总体多样性或特定生境的生物异质性。Beta多样性分析往往通过计算样本间的...
然后将工作目录设置到C盘mywd文件夹，并读取data.xlsx的内容到workbook变量中。data.xlsx必须是经过标准化的菌属相对丰度表，其格式应为：第一行为菌属名称，其余每行代表一个样本，每列代表一类菌属在每个样本中的相对丰度。使用vegan包中的diversity函数计算shannon多样性，并将结果存储在alpha_shannon变量中，然后写...
Sepkoski JJ Jr (1988) Alpha, beta, or gamma: where does all the diversity go? Paleobiology 14: 221-234.Sepkoski J J Jr. Alpha, beta, or gamma: where does all the diversity go[J]. Paleobiology, 1988, 14(3):221-234.Sepkoski, J.J. (1988) Alpha, Beta, or Gamma: where does all...
The latitudinal distribution patterns of alpha, beta and gamma diversity of reptiles, amphibians and herpetofauna were analyzed using individual binary models of potential distribution for 301 species predicted by ecological modelling for a grid of 9,932 quadrants of ~25 km2 each. We arranged ...
α多样性(Alpha Diversity)即生境内的多样性(within-habitat diversity)，是指某一栖息地或微生物群落在...
simpson_diversity <- 1 / (1 - gini_simpson_index) Simpson 均匀度(equitability 均匀度) equitability <- 1 / (richness * (1 - gini_simpson_index)) Chao1 & ACE Chao1 指数 chao1 <- estimateR(otu)[2, ] ACE 指数 ace <- estimateR(otu)[4, ] ...
...Hard Latency Constraint 前面介绍过用于控制延迟时间的因子 $\alpha$和$\beta$,实验对比了两组参数设置: $\alpha=0,\beta=-1$ $\alpha=-...0.07,\beta=-0.07$。...[layer diversity] 最后作者还对比了使用单一操作组成的网络结果对比,实验结果如下,可以看到虽然只使用MBConv5(k5x5)最终accuracy最高,...
Molecular Diversity Preservation InternationalEntropyCichocki, A., Cruces, S. & Amari, S. 2011. Generalized alpha- beta divergences and their application to robust nonnegative matrix factorization. Entropy 13: 134-170.Cichocki, A.; Cruces, S.; Amari, S.I. Generalized alpha-beta divergences and ...
High diversity of alpha, beta and gamma human papillomaviruses in genital samples from HIV-negative and HIV-positive heterosexual south African men. Papillomavirus Res. 2017;3:160–7. https://doi.org/10.1016/j.pvr.2017.05.001 Epub 2017 May 10. Article PubMed PubMed Central Google Scholar ...
1)alpha diversityalpha多样性 1.Additive partition of diversity approach is used to analyzing the relative contribution ofalpha diversityand beta diversity to gamma diversity of plant species in oak(Quercus liaotungensis) forest in a quadrat,slpoe positon,slope three scales hierarchical sampling system...