Plant Diversity and Structural Patterns in Stanului Forest, Gemărtălui Valley, Romania

This study provides the first comprehensive structural and diversity assessment of the Stanului Forest ecosystem since the last taxonomic survey conducted in 1987. The paper analyses the structural indices of biocoenosis and vegetation diversity in the Stanului Forest ecosystem (Gemărtălui Valley), in the hilly area of Oltenia (Romania), in Dolj County. Primary data were obtained using randomised sampling with frame squares, which ensured the random selection of sampling units and standardisation of the data collection process. The number of samples was equal (10) across all vegetation categories studied. The sampling area was 1 m2 for herbaceous species and 100 m2 for woody species. Structural indices (frequency, constancy, dominance index, index of relative significance, etc.), diversity indices (Shannon–Wiener, Gleason, Simpson), and statistical analyses were used to interpret the data. The results showed that from a taxonomic perspective, 5 families of woody species and 15 families of herbaceous species were identified. The presence of the invasive species (Robinia pseudoacacia) can negatively influence the ecological functions of the existing plant community. The species Quercus frainetto and Carpinus betulus accounted for 55.16% of the woody layer dominance. In the herbaceous layer, Carex sylvatica and Schedonorus giganteus recorded the highest dominance values. The Shannon–Wiener diversity index was 0.53 in the woody layer and 0.50 in the herbaceous layer.