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Spontaneous regeneration of the Carpathian beech forest in planted pine stands of the Roztocze National Park (the Roztocze Highlands, south-east-Poland)

Maciejewski Z.

Polish Journal of Ecology

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2011

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Vol. 59, nr 2

235-248

EN

Directions and the scope of changes in the species composition of individual layers in secondary pine communities belonging to the class Querco-Fagetea Br.-Bl. & Vlieg. 1937 (tree stand, shrubs and vascular plants of the herb layer) observed at two study plots over almost 40 years (from 1971 until 2009) are discussed. Both tree stands were planted and they are in the phase of spontaneous regeneration towards a potential natural community . the Carpathian beech forest Dentario glandulosae-Fagetum Oberd. 1953. Species with greater light requirements (pine Pinus sylvestris L., aspen Populus tremula L., oak Quercus robur L., ecologically alien to the potential plant community, retreat from the tree and shrub layers. The share of tree species typical of the potential community (beech Fagus sylvatica L., hornbeam Carpinus betulus L., sycamore Acer pseudoplatanus L.) - in the tree stands increases. The rate of changes is particularly high for beech, while regression symptoms are noticed for fir Abies alba Mill.: a decrease in the abundance and share of fir in both tree-stands was recorded. A decrease in the abundance and frequency of the majority of species, including species characteristic of deciduous forests (class Querco-Fagetea) and beech forests (order Fagetalia sylvaticae Pawł.1928), and an increase in species typical of alder-ash riparian forests (alliance Alno-Ulmion Br.-Bl. & Tx. 1943) and nitrophilous communities were observed in the herb layer. Conversion treatment may reinforce the artificial character of the community because the species composition, as well as the spatial and age structure of the tree stands, can be arbitrary and therefore artificially formed during conversion (arbitrary applied size and order of regeneration clumps and areas). When anthropogenic communities are left undisturbed, processes affecting all phytocoenotic layers are activated and spontaneous forest regeneration usually begins. Therefore, tree-stand conversion used as a tool to restore natural community is not effective.

2

Changes of flowering phenology of six herbal species in a beech forest (Central Slovakia): a decade analysis

Schieber Branislav

Polish Journal of Ecology

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2007

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Vol. 55, nr 2

233-244

EN

The variability in flowering phenology of six forest herbaceous species: Pulmonaria officinalis L. (early spring species), Dentaria bulbifera L. (mid spring), Galium odoratum Scop, (late spring), Veronica officinalis L. (early summer), Mycelis muralis (L.) Dumort. (mid summer) and Campanula trachelium L. (mid/late summer) was analysed over the period of the past ten years (1995-2004). Observations were done in a beech forest at the Ecological Experimental Stationary in Kremnicke vrchy Mts (Central Slovakia, 48[degree] 38'N, 19[degree] 04'E, 450-520 m a.s.l.)- Two phenological events - the first flowering and full flowering as well as the duration of interphase interval were analysed. The timing of observed phenological events was related to selected climatic factors (temperature and precipitation). The highest variation in the first flowering date was observed in early spring species- standard deviation (SD) was equal to 7.2 days. As for full flowering date, the highest value of standard deviation was detected in late summer species (SD = 8.5 days). In respect to the duration of inter-phase interval (in days), the highest relative vari.ability (c[v] > 53%) was ascertained in early spring species. The significant correlations (P <0.001) were detected between dating of full flowering and cumulative temperatures in all phenological types (excepting early spring); the coefficients of correlation (r) moved from - 0.85 (early summer and mid summer species) to - 0.91 (mid spring species). Significant correlations were revealed between precipitation and timing of flowering only for mid summer (r = +0.70) and late summer species (r = +0.75), respectively. Despite of the fact, that no significant trends were detected in timing of flowering in the species, the effect of the global warming is evident. The values of the possitive deviations of the mean air temperatures averaged for the period of the last decade were increased in comparison to the long-term mean. Onsetof flowering has been shifted earlier a few days in majority of the spe.cies during the past decade. Decade tendency showed a slight increasing of values of cumulative temperatures during the periods crucial for the development of the phenophases.

3

Ecological characteristic of rare species : the case of parasitic hymenoptera

Ulrich W.

Polish Journal of Ecology

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2001

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Vol. 49, nr 4

379-389

EN

Ecological characteristic of relatively rare (singleton) hymenopteran species sampled in a beech forest on limestone are studied. No marked differences between singleton and non-singleton species occurred in regard to guild membership, stratum of host attack and phenology. There was however a strong effect of sample size on the fraction of singletons. Body size and phylogenetic position also appeared to influence rarity, but it proofed to be difficult to separate the effects of both variables. Rare species appeared to have larger density fluctuations but - in line with the theory of local mate competition - lover sex rations than more common species. Brachypterous and apterous species had lower fractions of singletons. This result contradicts theoretical expectations of metapopulation models.

4

Niche segregation and coexistence of parasitic Hymenoptera of the Apilota genus group (Hymenoptera, Branconidae) in a beech forest on limestone

Ulrich W.

Polish Journal of Ecology

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2000

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Vol. 48, nr 3

225-238

EN

In a beech forest on limestone (Northern Germany) community structure and coexistence of a community of phorid (Diptera) parasitoids (Aspilota and Orthostigma spp., Hymenoptera, Braconidae) was studied. A classical niche analysis including character displacement, temporal and spatial segregation and density fluctuations could not clearly separate the species. In a case where such a separation by morphological factors was possible, hosts and spatial distribution of this species were the same as in morphologically different species. As prediced from aggregation theory of coexistence all species were highly aggregated but aggregation and density appeared not to be correlated. In line with the core-satellite hypothesis bimodal species rank order distributions (temporal and in relation to density) with a high number of rare species were found and patch density was correlated with number of patches occupied. Relative abundance distributions were fitted by Zipf-Mandelbrot but not by log-normal or log-series models.

5

Temporal stability of community structure of the parasitic Hymenoptera in a beech forest on limestone

Ulrich W.

Polish Journal of Ecology

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1999

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Vol. 47, no 3

257-270

EN

The stability of the community structure of the parasitic Hymenoptera of a beech forest on limestone (northern FRG) was studied. The annual number of species was around 350 to 450 with a high degree of species turnover. In a comparison of the study years the species identity of the abundant species turned out to be low and their dominance rank order was highly variable. The yearly sequence of emergence appeared to be constant. Density fluctuations of the species were high and positively correlated with mean density and negatively with the weight of the species. No clear common temporal trends in density could be detected. Host guild, stratum of host attack or number of generations did not detectably influence the degree of density fluctuations of the species. The findings are discussed in the context of concepts of stability and classifications of communities and it is concluded that this hymenopteran community is best described as non-interactive and non-stable.

6

The parasitic Hymenoptera in a beech forest on limestone. 1, species composition, species turnover, abundance and biomass

Ulrich W.

Polish Journal of Ecology

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1998

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Vol. 46, no 3

261-289

EN

Between 1980 and 1987 a beech forest (Fagus sylvatica) on limestone near Gottingen (FRG) was studied using ground-photo-electors. 720 species of Hymenoptera were detected. 669 of the species were parasitoids, 29 phytophagous Tenthredinidae, Cynipidae and Eurytomidae, 9 ants, 4 vespids and 9 nest-building sphecids, megachilids, andrenids and bumble bees. Even after 8 years of sampling a great number of species seems to remain undetected. Estimates of extiction and immigration rates indicate species turnover rates of at least 5 to 10%. The abundance of the parasitic Hymenoptera ranged between 123 +- (1981) and 1078 +- 186 (1984) ind. m^-2 a^-1. The most important groups were the parasitoids of Diptera with 56 +- 15 (1981) to 936 +- 164 (1984) ind. m^-2 a^-1. As judged by the sorting according to parasitoid guild, the parasitoids of gall-makers (23 +- 9 to 880 +- 163 ind. m^-2 a^-1) and the egg-parasitoids (21 +- 17 to 102 +- 33 ind. m^-2 a^-1) reached the highest densities. The biomass of the parasitic wasps ranged between 19 +- 5 (1981) and 170 +- 92 (1987) mg DW m^-2 a^-1 with a mean of 68 mg DW m^-2 a^-1. In comparison with other important insect taxa this is a low value.