我有个微生物相对丰度数据，想对分组 group 进行检验分析，采用 adonis 和 anosim 进行。结果如下：

• adonis

Permutation test for adonis under reduced model
Permutation: free
Number of permutations: 999

vegan::adonis2(formula = specmat ~ group, data = specmat.meta, by = NULL)
          Df SumOfSqs      R2      F Pr(>F)    
Model      1   0.4066 0.06274 10.978  0.001 ***
Residual 164   6.0742 0.93726                  
Total    165   6.4808 1.00000                  
---
Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1

• anosim

Call:
vegan::anosim(x = specmat, grouping = specmat.meta$group) 
Dissimilarity: bray 

ANOSIM statistic R: 0.06837 
      Significance: 0.001 

Permutation: free
Number of permutations: 999

我的问题是， adonis2 的 R2 = 0.06274 和 anosim 的 R = 0.06837 ，这个值会不会太小了，不足以解释差异？