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The structural composition of the forest habitats is considered to be one of the most important factors affecting the breeding bird community composition. Structurally more homogenous forests are usually characterized by lower number of bird species and their densities. This study presents results of a comparison of the breeding bird communities in three Carpathian mountain forests, and the effect of the forest composition on breeding bird species richness and density. There are the bird communities occurring in semi-natural forests: natural mixed forest (NMF) – spruce-beech forest situated ca. 1000 m a.s.l. and UFZ-spruce forest in the upper forest zone (UFZ) up to 1510 m a.s.l., and the managed spruce forest (MSF) at altitude which is similar to NMF. The territory mapping method was used to estimate the number of breeding species and their densities during years 2004– 2006. The species richness as well as the density of breeding bird communities were found to be higher in the semi-natural habitats (33 breeding species; 64.6 breeding pairs 10–1 ha in NMF and 8 breeding species; 57.6 breeding pairs 10–1 ha in UFZ) than in the managed habitat (21 breeding species; 53.6 breeding pairs 10–1 ha). This was true even for the high-elevated study plot despite the fact that the altitude is usually negatively correlated with both the species richness and density.
The influence of felling on the distribution of rodents and their predators in a transitional coniferous-deciduous forest in northern Belarus was investigated in relation to stand age, forest type, and soil richness. The study was conducted in two areas differing by top-grounds (clay and sand soils) and, in turn, having different habitat carrying capacities. Three forest parts were investigated: 1) 10%, 2) 20–30%, and 3) 40– 60% covered by recent clearcuts. Three age classes of the clearcuts, namely 1) less than 2 years old, 2) 2–5 years old and 3) 6–12 years old, were considered. In total, we obtained data on small rodent numbers in 84 clearcuts, and the data on predators – in 67 clearcuts and the woodland parts differed by logging rate. Eventually, we became convinced that felling generally led to an increase in the abundance and species richness of rodents and their predators and that was attributable in the clearcuts aged up to 12 years. First, logging led to higher densities of Apodemus mice, the red fox Vulpes vulpes L., weasel Mustela nivalis L., tawny owl Strix aluco L., common buzzard Buteo buteo L. and adder Vipera berus L. Also, with the increased felling rate Microtus voles and the longeared owl Asio otus L. penetrated in transitional woodlands. Too intensive forest harvesting (more than 40% of recent clearcuts) led to the decline in the populations of several predatory species such as the pine marten Martes martes L., Tengmalm’s owl Aegolius funereus L., Ural owl Strix uralensis Pall., and pygmy owl Glaucidium passerinum L. The decline in rodent predators found in the conditions of too intensive logging rate was different in the woodlands on sand and clay top-grounds. In the conditions of clay soil too intensive felling led to the pronounced decline of a marked part of the rodent predatory guild inhabiting woodlands, and the species densities decreased to the level that was lower than the initial one. Conversely, in initially poor habitats in the woodland on sandy deposits, logging of any rate led to the increase in numbers of rodents and their predators compared to undisturbed forest. But moderate logging was found to be the most favourable for the community there.
The first records of Lordithon bimaculatus (Schrank, 1798) from Poland are presented. Until 2000 this species was not distinguished from Lordithon trinotatus (Er., 1839). It was collected in the Karkonosze Mountains, in the Bialskie Mountains, as well as in the foothills of the Sudety Mountains, in subalpine spruce forests and in colline and montane mixed forests.
The objective of this study was to estimate the edge effect on the species richness in agriculturally maintained forest-grassland boundaries of coniferous forest and to determine how species respond to a forest edge. We hypothesised that species number, cover of herbs and mosses is higher in the edge, and species penetrates from nearby grasslands into forest interior. The study was conducted in the Southwestern Lithuania. The edge effect on overall herbaceous species composition of coniferous forests was evaluated by Canonical Correspondence Analysis. The species richness of herbs and mosses in the coniferous forest was highest in the forest edge and declined towards interior. The highest decrease in the number of species occurred within 0 to 5 m to the edge. The highest cover of herbs and mosses was in the forest edge and decreased towards the forest interior. CCA biplot showed a good correlation of overall species composition and the distance to the forest edge. Distribution of species along edge to interior gradient depended on the species response to different ecological factors. Ellenberg value of light was higher in the edge. Ellenberg value of nitrogen was higher in the forest interior.
Ecologists agree that one of the main effects of human activity is the decrease in patch size in the landscape and hence an increase in ecotone length as a transition zone between adjacent ecological systems. Theoretical and practical importance of this concept has become one of the leading issues in current ecological research. The ecological importance of the ecotones was investigated, in the boundary of natural forest complex of the Kampinos National Park and adjacent anthropogenic ecosystems. Quantitative and qualitative changes of plant communities and of dipterans (Chloropidae) – important pests of wild and crop plants – were recorded along four types of transects located at the distance of 3 km: 1/ mixed forest (Querco roboris-Pinetum Mat. 1981) – ecotone – managed meadow (Deschampsietum caespitosae Hor vatic 1930); 2/ mixed forest – ecotone – crop field (Arnoserido-Scleranthetum R.Tx.1937); 3/ mixed forest – ecotone – spontaneously growing 20-year-old birch wood; 4/ mixed forest – ecotone – planted 17-year-old pine wood. The exchange of plant and dipteran species between forest ecosystem and its surrounding was analysed. The role of ecotones as transit zone or barrier for such exchange and as optimum or exclusive habitat for plant and dipteran associations was evaluated. Botanical studies showed that the neighbouring, ecotone-forming communities differed markedly in the vegetation structure and species composition (similarity index between them varied from 8 to 47%). Width of contact zones was also different, ranging from 4 to 14 m. Therefore, two groups of transects were distinguished: mixed forest – young woods and mixed forest – agricultural communities which differed in plant species richness and vegetation structure in particular transect zones. It created clear contrast between ecosystems and their ecotones. Some species were being found exclusively in ecotones but these species differed among different ecotones. The so-called ‘edge effect’ was manifested in increased number of plant species in the ecotone compared with neighbouring ecosystems, higher density of some populations and their better life condition (reflected in individual’s size, earlier entering subsequent phenological phases, fecundity). Chloropidae mainly dwelled the transect of mixed forest – meadow (60% of all caught in study area) and mixed forest – crop field (24%). Only 16% of dipteran species were caught in the transect of mixed forest – woods. Phytophagous species dominated in the first two transects (80–86% of the total number). Saprophagous species were 4–6 time less numerous there. The proportions of both trophic groups were more uniform in the transect of mixed forest – woods. Of the 44 Chloropidae species only 10 (22%) were widely dispersed in the study area and only two species – the dangerous pests Oscinella frit L. and O. pusilla Mg. were noted in all zones of all studied transects. In the transects of mixed forest and anthropogenicecosystems, only meadow and crop field created optimal habitats for Chloropidae They were ‘ecological traps’ that maintained over 66% of all dipterans caught in the study area. This finding contradicts the supposition of potential threat posed by these pests to protected forest grounds due to a proximity of nearby meadows and croplands. Similarly, there was no threat of penetrating the sustainable mixed pine forest complex by synanthropic plant species. They were mainly found in the crop field. Only 1/3 of these species permeated to the ecotone zone, but none to the forest.
This paper describes the fruiting phenology and avian frugivory of Streblus asper (Moraceae) in a mixed dry deciduous forest, Anaikatty hills, Western Ghats. Fruiting occurred during April-June. Nine species of birds were found to feed on the ripe fruits of this species. Bulbuls (3 species) belonging to Pycnonotidae, followed by two species of Myna (Sturnidae) made majority of the feeding visits and appear to be the major seed dispersers of this species.
Recent studies have demonstrated the higher likelihood of regeneration in forest gaps compared with the understory for the dominant species in pine-oak mixed forest. Here, we tested whether rodent seed predation or dispersal was beneficial for gap regeneration. We tracked the seed predation and dispersal of Quercus aliena var. acuteserrata and Pinus armandii using coded plastic tags in the forest understory close to gaps. Our results demonstrated that the proportions of initial buried seeds of both species were significantly more abundant in the forest understory compared with gaps. After seed caching, however, significantly lower proportions of the seeds of both species survived in the forest understory compared with gaps during the 30-day observation period. The final survival proportions of the seeds cached in the forest understory were lower than those cached in the gaps the next spring, which indicated that small rodents rarely retrieved scatter-hoarded seeds from forest gaps. Our findings suggest that rodent seed predation patterns contribute to the regeneration of the dominant species in gaps compared with the understory in a pine-oak mixed forest. In the study area, reforestation usually involves planting seedlings but direct sowing in forest gaps may be an alternative means of accelerating forest recovery and successional processes.
This study concerns the observations and measurements of snow-cover carried out during the period from 1970 to 1997 in the open area and in the fir-spruce forest at the Station of Phytoclimatic Research at Kopciowa in the Beskid Sądecki Mountains. It was found that the average duration of a stable and compact snow-cover is 118 days in the open area and 126 days in the forest. On the average snow appears on 13 November in the open area, and 7 days later in the forest. It disappears on 23 March from the open area, and nearly 3 weeks later from the forest. In the first half of the winter season the average depth of snow-cover in the forest is only a little smaller than in the open area, and it is characterized by a slightly greater variation. While from mid-February the snow-cover in the open area is thinner, and is much more variable than in the forest.
Forest communities dominated by noble broad-leaved trees (maple, lime and ash) in Europe are of elevated scientific and conservation interest for the European Union. In this paper, we first present a synthesis of the maple and ash forests in peninsular Italy. By classifying these forests, we distinguish seven main groups for the territory, which only broadly match the syntaxa proposed in the literature. The variability of the Apennine data is then analysed floristically and phytogeographically (using chorological components) in a central-southern European context, using numerical classification, INSPAN, and direct ordination of several synoptic tables. These analyses allow us to identify six different groups of European Acer-Fraxinus communities. Canonical Variates Analysis (CVA) of the geographical components confirms the existence of distinct phytogeographical groups. In particular, we highlight the clear distinction between central European (including the Alps) and southern European coenoses. Among the latter there was a clear floristic and chorological distinction between Balkan and Apennine groups. These results reflect the biogeographical subdivisions of Europe, but do not support the syntaxonomical schemes proposed by other authors, which are based only on floristic-ecological information or (recently) use a smaller data set of Italian relevés. This study also shows that syntaxonomical schemes above the association level should pay more attention to phytogeographical aspects rather than focus on floristic-ecological information alone, in order to propose models that are of value on a geographical scale.
The present studies deal with the practical and theoretical problems of meadows in structure and functioning of the forest complex. Floristic, phytosociological and entomological studies involved fragments of two meadows located in large forest complex Kampinos National Park (Central Poland): a ‘mid-forest’ meadow surrounded by forest and ‘near-forest’ meadow situated in the boundary between forest and open area. The plant community developed on mid-forest meadow can be classified as Lysimachio-Filipenduletum ulmarie Hadč et al. 1997, on near-forest meadow as Deschampsietum caespitose Horvatic 1930. Both studied meadow communities are very widespread in Kampinos National Park and in whole Poland. Insect community containing various trophic guilds from Chloropidae family (Diptera) was chosen as representative of the entomocoenosis. From the standpoint of landscape ecology the processes of plant and insects species dispersion from meadow to forest and vice versa, across the forest meadow ecotone were analysed. The obtain results revealed that the meadows and their ecotones are refuge habitats for many plant and Chloropidae species increasing plant and entomofauna biodiversity of forest landscape. Proximity of meadows did not cause significant changes in the floristic composition of forest vegetation. Fears concerning the negative impact of meadows on natural forest vegetation through penetration of alien plant species and phytophagous Chloropidae seem to be unfounded. Ecotone was an important barrier for most plant and Chloropidae species in their dispersion from meadow to forest and vice versa. In the case of mid-forest meadow 93% of plant species did not cross ecotone, for near-forest meadow it was 83%. A high index of dispersion of Chloropidae species in mid-forest transect and poor differentiation of their numbers between zones indicate substantial colonisation of the whole system by Chloropidae, however, ecological properties of this fauna (saprophage species, a lack of distinct dominant, low density) minimised the risk it might pose to meadow complex or to adjacent forest. Near-forest meadow with much richer and diverse Chloropidae fauna contributed minimally to the fauna of ecotone and adjacent forest. Only 25% of species number of Chloropidae colonised all zones of the transect there and their majority (55%) exclusively inhabited the meadow ecosystem. It was found, that, from the point of view of natural forest protection, the role of adjacent meadows is very significant. They make ‘traps’ for certain groups of phytophagous insects.
Every year forest soils are enriched with nitrogen and phosphorus compounds due to the fall of leaves and litter of conifer needles, mineralization of ground cover and decaying tree roots, as well as precipitation. The process has been examined in two forest ecosystems: a mixed forest (plot I) and a young wood (plot II). The overall fall of duff collected in the young wood of the Słowinski National Park (plot II) has been 3.014 t/ha·year, which constitutes 69.35% of the fall collected in the mixed forest (plot I) on this territory (4.346 t/ha·year). The maximum intensity of duff fall occurred in autumn months and constituted 62.36% and 64.20% of annual fall respectively. Totally, 46.96 kg/ha·year of N and P were supplied to the soil of the plot I and 22.04 kg/ha·year in the case of the plot II. The precipitation enriched the soils of the mixed forest by 33.66 kg/ha·year of nitrogen and 1.19 kg/ha·year of phosphorus, the soils of the young wood – by 23.06 kg/ha·year of nitrogen and 0.92 kg/ha·year of phosphorus.
The silver fir (Abies alba Mill.) in the area of Wał Trzebnicki is at the northern limit of its distribution in western Poland. This study was performed in three nature reserves with protected silver fir populations. The stands in these reserves were mixed, with complex spatial structure and abundant tree regeneration. The proportion of fir in stands was around 16% of DBHS, the age of trees reached around 130 years. The silver fir occurs mainly in the sapling stage, whereas the number of seedlings was very low. The results of this study show the influence of forest floor vegetation as well as litter type on the emergence of fir seedlings. The seedlings density was compared with the results of other studies from different geographical areas and stands type in Poland.
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