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1

Wild boar density drives Metastrongylus infection in earthworm

100%
Nagy G., Csivincsik A., Sugar L.
Acta Parasitologica
|
2015
|
tom 60
|
nr 1
2

Influence of the population density and the amount of food on Chironomus plumosus [L.] and Tubificidae. Laboratory experiments

100%
Kajak Z., Prus P.
Polish Journal of Ecology
|
2004
|
tom 52
|
nr 1
The aim of this paper has been to examine experimentally the importance of the density of larvae and of the addition of the food for Chironomus and Tubificidae using selected parameters and indices of their populations. Increase of the density of Chironomus plumo- sus larvae (0.5–50.0 thousands ind. m⁻²) in laboratory experiments resulted in the decrease of emergence of imagos, number of tube apertures (3.5–0.4 apertures ind.⁻¹), and in the lower rate of tubes building. The addition of the food (powdered dry daphnids or food tablets for aquarial fish) had only slight effect on tube numbers but it decreased clearly the getting out of larvae from tubes (probably due to improved feeding conditions inside tubes). It had also a slight negative effect on the survival of larvae. Numbers and individual growth of Tubificidae were positively dependent on the addition of the food (also in the form of naturally dead Chironomus larvae) and negatively – on the density of Chironomus.
3

Understanding the dynamics of bank vole populations: demographic variability, stochasticity and density dependence

100%
Yoccoz N. G., Stenseth N. C.
Polish Journal of Ecology
|
2000
|
tom 48
|
nr Suppl.
4

Breeding parameters and recruitment in Feral Pigeons Columba livia f. domestica

84%
Hetmanski T., Barkowska M.
Acta Ornithologica
|
2008
|
tom 43
|
nr 2
159-166
This research was conducted on the Feral Pigeon population in Słupsk (NW Poland). Breeding parameters and the number of parental pairs' young recruited into the breeding population were determined for 52-112 marked pairs over three breeding seasons. Pairs had an average of 4.4 broods and produced 3.6 fledglings per breeding season. From 39 to 49% of pairs in various seasons did not have any young recruited. Every fourth pair (25-30%) had a single young bird recruited, from 12 to 20% of pairs — two young, from 4 to 11% — 3 young, and 6% of pairs had from four to six young recruited. The number of recruits depended on the breeding parameters of the parents: it was lowest among young pairs (low quality birds), those that began breeding late in the season, had a short breeding season, or low breeding success. In contrast, high quality birds with a long breeding season, the highest reproductive parameters and breeding success, had the most young recruited. Survival rate of young after leaving the nest was not found to be influenced by the starting date or the length of the breeding season of pairs. However, nesting conditions, such as pair density in colonies, may influence the fate of young birds after they leave the nest and are recruited.
5

Effects of environmental and spatial heterogeneity on tree community assembly in Baotianman National Nature Reserve, Henan, China

84%
Jia H.-R., Chen Y., Yuan Z.-L., Ye Y.-Z., Huang Q.-C.
Polish Journal of Ecology
|
2015
|
tom 63
|
nr 2
The debate on species coexistence mechanisms never stops. The niche theory, neutral theory, and negative density dependence mechanism has been attracting considerable attention in recent years, but an integrated research on species coexistence mechanisms has rarely been conducted. In this study, a previous investigation at a plot in Henan Province was used as a basis to analyze the spatial structure of the community with principal coordinates of neighbor matrices (PCNM). Variance partitioning was used to analyze the effects of topography, soil, spatial, and stand density on species distribution. Results show that the community structure in the broad, medium, and fine scales generally showed a highly significant spatial structure. Topography, soil, spatial variables, and stand density explained 3.4, 11.7, 12.1 and 19.49% of species distribution, respectively. The aforementioned results suggest that spatial factor was an important factor that affects community structure. Species distribution was evidently influenced by environmental spatial heterogeneity. It had a very important function for density-dependent effects acting on species distribution. Niche theory, neutral theory, and negative density dependence mechanisms affected community building in different degrees.
6

Species composition, coexistence and mortality factors in a carrion-exploiting community composed of necrophagous Diptera and their parasitoids [Hymenoptera]

84%
Ulrich W.
Polish Journal of Ecology
|
1999
|
tom 47
|
nr 1
7

Effects of the density of larvae and type of substrate on Chironomus plumosus L. [Diptera: Chironomidae] population. Laboratory experiments

67%
Kajak Z., Prus P.
Polish Journal of Ecology
|
2001
|
tom 49
|
nr 4
8

Population dynamics of Clethrionomys glareolus and Apodemus flavicollis: seasonal components of density dependence and density independence

67%
Stenseth N. C., Viljugrein H., Jedrzejewski W., Mysterud A., Pucek Z.
Acta Theriologica. Supplement
|
2002
|
tom 47
|
nr 1
Using long-term data on two forest rodent species [the bank vole Clethrionomys glareolus (Schreber, 1780) and the yellow-necked mouse Apodemus flavicollis (Melchior, 1834)] from the Białowieża Primeval Forest (E Poland), we decompose the annual density-dependent and density-independent structures into their seasonal components. For this purpose we adopt a state-space modelling approach explicitly incorporating sampling stochasticity. As density-independent factors we use the North Atlantic Oscillation (NAO) - a proxy variable for the overall climatic condition - and data on annual seed production. We find a weak effect of the NAO in the annual models for both species as well as during the winter in the seasonal model for C. glareolus. The effect of the NAO disappears, however, when seed-crops are incorporated into the models (for both the annual and the seasonal - suggesting that NAO primarily affects seed production). Seed production enters the models with a positive effect during the winter only, suggesting that the among-year variation in rodent density is primarily accounted for by differences in seed-production, particularly oak seeds. For A. flavicollis, a slightly positive effect of hornbeam also appears in the summer dynamics. The obtained results are discussed on the basis of earlier studies on the same populations, on the same species studied elsewhere as well as on the basis of general ecological insight.
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