I am working on a study where I have species presence/absence data for 80 independent sites, as well as the soil carbon values for each of the sites. I want to test whether the presence/absence of each species is related to the site's soil carbon value. In other words, which species coincide with site that have high soil carbon, and which species coincide with site that have low soil carbon.
Since I have a binary predictor variable, and a continuous response variable, what would be the best approach for this analysis?