Ábrahám Levente (szerk.): Válogatott tanulmányok VII. - Natura Somogyiensis 22. (Kaposvár, 2012)

Winkler D. - Erdő Á.: A comparative study of breeding bird communities in representative habitats of the Sárosfő Nature Reserve area

Winkler D. & Erdő Á.: Breeding bird communities

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Table 3: Comparison of Shannon diversities using Hutcheson's t-test

(t-values, ***P=0.01; **P=0.05; *P=0.1; ns - not significant)

reedbed

meadow

oak

afforestation

oak forest

meadow

0.0323 ns

oak afforestation

6.0413"

4.7602"

oak forest

5.4661"

4.3086"

0.7881 ns

ash-aldcr forest

9.2026'"

7.0226"'

3.9198"'

4.8414'"

pine forest

1.9473 ns

1.7179 ns

2.7483'

2.2712'

ash-aldcr

forest

5.0552"'

allochthonous Scots pine forest. Nevertheless, this habitat was responsible for the occurrence and nesting of species connected to coniferous forest, such as the Coal Tit (Parus ater) or the Crested Tit (Parus cristatus), thus increasing the summarized species richness of the whole study area.

Shannon diversity showed a similar trend (Fig. 2b) expressed in species richness. Its numerical value was the highest (3.013) in the riverine ash-alder woodland area while the lowest (1.205) in the reed habitat.

Breeding pair density was the highest (64.54 pairs/10 ha) in the riverine ash-alder forest, but it was also considerable (~44 pairs/10 ha) in the low pole oak stand (Fig. 2c). Total density of bird community was fairly low (~6 pairs/10 ha) in the reed and meadow habitats.

The community dominance index is a simple characteristic calculated as the percentage of the total abundance of all species in the community that is contributed by the two most abundant species (Fig. 2d). It can therefore be an appropriate characteristic for evaluating the dominance structure of bird communities. Its value was considerably high in the reedbed and meadow habitats that can be explained with the low number of spe4» 4X 0 96

1 92 2 44»

alpha

Fig. 3: Diversity profiles of breeding bird communities in the different habitats