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sampling design applied for this purpose and the information on the number of sample areas are given in Table 1. In the study, a total of 640 quadrate samples were taken from fir stands. Trojan fir stands are divided into GA, GB, GC and GD groups (stand types) according to their structure. This distinction is made according to the distribution of the number of trees in the area to the diameter classes (Figure 2). GA stands represent a relatively old forest, and there is an excess in the thick diameter class of actual structure compared to the assumed optimal distribution of the tree numbers to the diameter classes. The GB type represents young stands, while GC stands represent middle-aged, vertically layered fir forests. The current number of trees in the thin layer in the GB stands and in the medium diameter class in the GC stands is higher than the optimal distribution. The GD type, on the other hand, shows different-aged vertically layered fir stands, which are not similar to the previous three types in terms of the distribution of stem numbers to the diameter class, and have an irregular structure. The stem volumes of the stands in the study area vary between 425-616 m³/ha, and basal area is between 41.6-55.7 m²/ha. Sampling of the lower flora was carried out by applying the quadrate (frame) method along the strips (transects) (Figure 3). Before going into the field, the transect lines and the quadrate sampling locations on these lines were determined on the map. Transect lines were determined to be generally parallel to contour lines and to cover the whole area of the stands. Transect lines were constantly changed in the samplings made in different observation periods, and it was aimed to represent the whole area of the stands. Therefore, sampling was made in different places in the stands each time. 10 quadrate samples were taken every month in each stand. In this way, a total of 160 quadrate samples were taken each month for 16 stands. Quadrate sizes were 0.5 x 0.5m=0.25 m² and the number of different plants included in the frame were recorded in the survey report sheets. The names of the plants known in the field were recorded on the sheets, and for those that could not be identified, explanatory statements were written and plant samples were taken or photographed to identify them in the herbarium. Calculation of Diversity Indices and Data Analysis – Izračun indeksa raznolikosti i analiza podataka The values of the indices used to define plant diversity vary depending on the number of taxa in the area, the number of individuals belonging to the taxa, or the homogeneous distribution of the total number of individuals to the taxa. In this study, plant diversity is expressed by taxa diversity. Different indices are used to determine vegetative diversity in an area. When revealing diversity, two factors are generally taken into account, the richness and the abundance. The greater the richness and abundance, the greater the diversity. The evenness value is an approach based on whether the taxa in the area are represented by an equal number of individuals. In this study, the Shannon-Wiener, Simpson dominance, Simpson diversity and Pielou’s evenness indices were used to define plant diversity. The mathematical expressions used in calculating the indices are given below (Simpson, 1949; Shannon and Weaver 1963; Pielou, 1966). Shannon-Wiener Diversity Index (SH): |