The study looked at different types of forests in the Loess Plateau of North Shaanxi Province to see which had the most species diversity. They used different measures like the Shannon-Wienner index and Simpson's diversity index. The results showed that Populus davidiana forests had the highest species diversity. They also found that the diversity was highest in the tree stratum compared to the herb and shrub strata. The evenness index showed that the tree stratum had the most balanced distribution of species.