(db.s1s2<-Spec.s1s2/(Abund.s1+Abund.s2)) #Site 1 compared to site 2
(db.s1s3<-Spec.s1s3/(Abund.s1+Abund.s3)) #Site 1 compared to site 3
(db.s2s3<-Spec.s2s3/(Abund.s2+Abund.s3)) #Site 2 compared to site 3