Ábrahám Levente (szerk.): Válogatott tanulmányok VI. - Natura Somogyiensis 19. (Kaposvár, 2010)

KOVÁCS GY., WINKLER D. & FARAGÓ S.: A kárókatona fészekalj és tojásméret vizsgálata a Kis-Balatonon és a Nagyberekben

270 NATURA SOMOGYIENSIS 0.80.7 5 0.6 3 M 0.5 0.4täO c CCA Ö e 00 c £ •c M 3 a. tu (ZI (Z) Fig. 8: Dendrogram based on cluster analysis using Jaccard's coefficient of similarity on the waterbird communities of different seasons Hierarchical cluster analysis separated the sampled habitats into two main groups (Fig. 8). The dendrogram well emphasises the complete separation of the winterbird community. In the second main group, the community of the autumn period clearly separates from the early spring, spring and summer communities, while species composition of the spring and summer communities showed the highest similarity. Shannon diversity and equitability were highest in the summer period and lowest in the winter period (Fig. 9, 10). The comparison of bird community diversities (Hutcheson's test) of different seasons yielded significant differences at p=0.01 level (Table 5). Rényi diversity profiles were used to rank the seasons according to diversity. The results show that some profiles, namely spring-winter, spring-early spring, summerwinter, autumn-winter, summer-early spring, autumn-early spring cross each other; therefore, these communities cannot be ranked. Notwithstanding, the other compared 3.0 2.5 2.0 1.5 1.0 0.5 0.0 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.0 SP SU AU W ES ST SP SU AU W ES ST Fig. 9: Shannon diversity in the different seasons; Fig. 10: Equitability in the different seasons (SP - spring, SU - summer, AU - autumn, W - winter, ES - early spring, ST - study period)