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1

Trophic structure of free-living nematode assemblages along a Southern Baltic transect

100%
Szulwinski M., Radziejewska T., Drgas A.
Folia Universitatis Agriculturae Stetinensis. Piscaria
|
2001
|
tom 28
2

An attempt to determine trophic structure of the bottom fauna in coastal waters of the Gulf of Gdansk

86%
Wiktor K.
Oceanologia
|
1985
|
tom 21
3

Ground-active arthropod recovery in response to size of shrub plantations in a desertified grassland ecosystem

86%
Liu R., Liu J., Zhao J., Xi W., Yang Z.
Polish Journal of Ecology
|
2017
|
tom 65
|
nr 3
The ground-active arthropod diversity response to size of shrub plantations in desertified grassland ecosystems is largely unknown. In the study ground-active arthropods were collected by pitfall trapping beneath shrub canopy of very low, low, medium and high size, with adjacent mobile sandy land as a control. It was found that arthropod dominant taxa from mobile sandy land were significantly distinctive from those from plantations of different shrub size. A considerably lower Sørensen index (i.e., 0.25–0.48) was found between the arthropod communities from mobile sandy land and the canopy of either shrub size, than between those under low and medium/high shrub size (i.e., 0.62 to 0.69). The arthropod total abundance was significantly greater under the shrub canopy of very low size in comparison to that of low and medium shrub size and mobile sandy land, with the intermediate values under shrub canopy of high shrub size. Taxon richness and diversity of arthropod communities were distinctly lower under the shrub canopy of low size in comparison to very low, medium and high shrub size. The shrub size was found to have different effects on the density and richness distribution of arthropod trophic groups (i.e., predators, phytophagous, saprophagous, and omnivorous). It was concluded that shrub plantations could facilitate ground-active arthropod diversity recovery when they were afforested in mobile sandy land. There was a contrasting effect of shrub size on ground-active arthropod diversity recovery versus arthropod abundance when grazing was excluded.
4

Soil nematodes in organic and conventional farming system: a comparison of the taxonomic and functional diversity

72%
Ilieva-Makulec K., Tyburski J., Makulec G.
Polish Journal of Ecology
|
2016
|
tom 64
|
nr 4
Agricultural practices in organic farming theoretically are supposed to lead to higher diversity and activity of soil organisms, which correlates with the stability or resilience of the soil system. In a 3-year study, we tested that hypothesis by comparing the nematode abundance, genera composition and community structure in the soil of winter wheat crop under organic and conventional management. We found the soil type to be a stronger predictor for the total nematodes abundance than the farming system itself. In both systems nematode densities were higher in the sandy than in the clayey soil. Total abundance of nematodes was significantly higher in the organic than conventional farm only in sandy soil and only in the autumn. Significantly more plant feeders was observed in organic than in the conventional crops regardless the soil type. In the clayey soil more bacterial feeders were found in the conventional farm, while in the sandy soil — in the organic one. Nematode generic richness was higher in the organic (a range of 15–35 genera) than in the conventional crops (a range of 15–29) on most sampling dates. Higher generic diversity (H') in the organic crop than in conventional was found for total nematodes in the clayey soil, and for hyphal feeders in sandy soil. H' for plant feeders were higher under organic than conventional system in both types of soil. In both farming systems bacterial feeding genera (Rhabditis, Panagrolaimus, Cephalobus and Acrobeloides) dominated in the communities. Plant feeders and omnivores were found among dominant genera only in the clayey soil, first under both systems, the latter only in the organic crops. The evaluation based on the ecological indices such as Maturity Index, Plant Parasite Index, Enrichment and Structure Index, and ratios between nematode trophic groups, showed that nematode communities under both farming systems most of the time were low matured and the soil food webs strongly disturbed.
5

Trophic structure of dipterous assemblages (Insecta: Diptera) in saline habitats of the Baltic coasts

72%
Kaczorowska E.
Fragmenta Faunistica
|
2007
|
tom 50
|
nr 2
6

Restoration of subalpine species-rich grasslands: short-term vs long-term changes in the density and diversity of above-ground insects

72%
Karg J., Kujawa K., Manhart C., Marschalek H., Neugebauer K. R., Sachteleben J.
Polish Journal of Ecology
|
2015
|
tom 63
|
nr 1
Due to decrease in the area of extensively managed, semi-natural grasslands, that contribute to high biodiversity level preservation, the conversion of highly productive meadows to extensively managed, species-rich grasslands is now regarded as an important task for nature conservation. The aim of this long-term study was to assess the significance of restoration measures for diversity and trophic structure of above-ground insect community. That study challenges some weaknesses of previous studies as it was conducted with the use of suction trap enabling quantitative analyses of the changes in most insect taxa, and in a long time-span (1992–2005) in a set of permanent plots. The study area was located in a subalpine zone in Bavaria, near Laufen (Germany). The restoration process was initiated in 1996 by a cessation of fertilization and reduction of number of mowing to 1–2 per year. The changes in insect density and diversity (number of families) were monitored in ten restored and two reference plots with the aid of a suction trap. The changes in the insect community recorded during 14 years support findings from other studies that response of insect community to restoration process is usually slow on average. The short-term comparison in 2004–2005 between the restored and reference plots show that the first ones were characterized by more diverse (in term of family number) insect communities (as a whole as well as in guilds of predatory and parasitic species). From the other side, the long-term trend analysis shows that since 1998–2000 insect diversity and abundance was declining. Also trophic structure is fluctuating without clearly defined trend. These findings are in line with the results of the analyses of taxonomic composition similarity. They did not support the expectations neither that difference between initial and current taxonomical composition in a restored plot increases in time (mainly because of incoming new species), nor that spatial heterogeneity of insect assemblages should increase. However, spatio-temporal insect interactions between sample plots (located close to each other), linked to high movement ability of many insect taxa, could mask the changes in insect community caused by restoration.
7

The structure of psammic rotifer communities in two boreal lakes with different trophic conditions: Lake Vortsjarv and Lake Saadjarv (Estonia)

72%
Lokko K., Virro T.
Oceanological and Hydrobiological Studies
|
2014
|
tom 43
|
nr 1
8

Community structure of soil-litter macrofauna in shelterbelt and adjacent crop field

72%
Olechowicz E.
Polish Journal of Ecology
|
2004
|
tom 52
|
nr 2
Studies were carried out in 1999 and 2000 in the vicinity of Turew near Poznaƒ (West Poland) and dealt with the composition, density and biomass of soil-litter macrofauna with special reference to dipteran larvae in the agricultural landscape. Sites were located on a 7- years old mid-field shelterbelt and on adjacent field with maize crop in the first and wheat crop in the second year of study and – on 9 various patches of vegetation within the mid-field shelterbelt. Studies carried out along the transect: the shelterbelt (S) – ecotone (E) – field 10 m (F 10)– field 50 m (F 50) demonstrated a decline of: 1) animal density (10 times) and biomass (30 times) of total macrofauna and (80 times) of dipteran larvae, 2) taxonomic richness and biodiversity measured with the H` index, 3) individual weight of the entire macrofauna, of dipteran larvae, saprophagous animals and predators so that the individuals became smaller with the distance from the shelterbelt, 4) similarity of macrofauna communities in terms of composition and dominance structure, with increasing distance between plots. Close relationship was found between plant cover and soil-litter macrofauna. Species composition, density, biomass and trophic structure of soil invertebrate community depended on tree or herb species. Those soil animals and especially dipteran larvae were a sensitive indicator of small-scale habitat changes.
9

Nematode abundance, diversity and trophic structure in relation to spatial heterogeneity of a natural fen

72%
Ilieva-Makulec K.
Polish Journal of Ecology
|
2004
|
tom 52
|
nr 3
Spatial distribution of nematode fauna was studied in relation to horizontal heterogeneity of a natural tall-sedge fen in north-eastern Poland. Due to vegetation patchiness at scale of several tens centimetres two distinct habitats can be distinguished – “tussocks” and sites “between tussocks”. Nematode fauna in the soil “between tussocks” was different from that of the adjacent “tussocks” sites with respect to total abundance, generic composition and community trophic structure. On the two sampling dates (in spring and summer) significant more nematodes were found in the “tussocks” than “between tussocks”. Nematode communities were more diverse in the “tussocks” than “between the tussocks”, however the differences between two sites were significant only in spring. Each site had its own dominant genera different from the dominant genera of the adjacent site. Spatial pattern of nematodes was dynamic over time and seemed to be highly influenced by seasonal fluctuations of floods, which make the sites “between tussocks” available for nematodes only when floods recede.
10

Nematofauna of the shelterbelts in the agricultural landscape

72%
Wasilewska L.
Polish Journal of Ecology
|
2004
|
tom 52
|
nr 2
Trophic structure, number and density of taxa, generic diversity, and maturity indices were compared for soil nematode communities inhabiting a 170-year-old shelterbelt, 6-year-old shelterbelt, and a maize field adjacent to the younger shelterbelt. The study was conducted in an area of long-term research near Turew (Wielkopolska Region, West Poland). Sampling sites in the crop field were located at distances of 0.5 m, 10 m and 50 m from the younger shelterbelt. In the soil of shelterbelts more taxa occurred in comparison with the cropland, the index of generic diversity was higher, the dominance of nematodes of the class Secernentea (r-strategists s.l.) over Adenophorea (K-strategists s.l.) was lower, community maturity indices and bacterivore maturity index were higher, and the ratio of plant parasite index to maturity index was lower, providing evidence for a more advanced stage of succession in the shelterbelts. In the maize field, fungivorous and plant feeding nematodes predominated, with a strong dominance of one of the taxa pathogenic to plants (Pratylenchus). The effect of 6-year old shelterbelt on nematode community in maize crop field was observed in the field part closest to the shelterbelt.
11

Planktonic ciliates of the Neva Estuary (Baltic Sea): community structure and spatial distribution

58%
Mironova E., Telesh I., Skarlato S.
Acta Protozoologica
|
2013
|
tom 52
|
nr 1
12

Soil and litter macrofauna in shelterbelts and in adjacent croplands: changes in community structure after tree planting

58%
Olechowicz E.
Polish Journal of Ecology
|
2007
|
tom 55
|
nr 4
Studies were carried out in the vicinity of Turew near Poznań (Western Poland) in the years 2003 and 2004 in three midfield shelterbelts of different age (150, 11, 6 years old) and along two transects across shelterbelt (6 and 11 years old) >ecotone> field at distances 15 and 50m from the shelterbelt. The field located in deforested area was treated as the control. The studies were aimed at estimating the changes in community structure (composition, density, biomass) of soil and litter macrofauna, (mainly dipteran larvae), related to shelterbelt age both within shelterbelts as in adjoining fields. The results were compared to previous studies carried out in 1999–2000 in the same agricultural landscape. The density and biomass of soil and litter macrofauna were many times higher in shelterbelts (2827–870 ind. m⁻² and 3782–521 mg.d.wt. m⁻²) than in fields (483–53 ind. m⁻² and 101–12 mg.d.wt. m⁻²) and increased with the age of planted trees. The same was true for taxonomic richness. Ecotone zone of both transects was characterised by the greatest density and biomass of animals, mainly those of mobile epigeic animals, particularly the ants. The density and biomass values were declining in the field with the increasing distance from the shelterbelt. Across the transect of an older (10–11 years old) shelterbelt and adjacent field the density and biomass of studied animals were higher in all plots than across the younger (5–6 years old) one. It can be concluded, that the effect of the shelterbelt increases with age of planted trees. The results confirm the previous suggestions of the enhancement of the field macrofauna by forested strips. The highest similarity in taxonomic and dominance structure was found between the shelterbelts and their ecotones and they differed significantly from those in the field.
13

Trophic structure of Ozark cave streams containing endangered species

58%
Graening G. O.
Oceanological and Hydrobiological Studies
|
2005
|
tom 34
|
nr 3
14

Soil-litter macrofauna in the mixed forest and midfield shelterbelts of different age [Turew area, West Poland]

51%
Olechowicz E.
Polish Journal of Ecology
|
2004
|
tom 52
|
nr 4
The paper deals with the composition, density and biomass of soil-litter macrofauna in four midfield shelterbelts of different age and, comparatively, in the neighbouring mixed forest. The increase was observed along with the shelterbelt ageing of: 1) numbers of all macrofauna and particularly of some taxa (Symphyla, Chilopoda, coleopteran larvae and imagines and some dipteran larvae), 2) biomass of all macrofauna, of soil fauna (Group I) and of coleopteran larvae, 3) share of zoophages in all macrofauna and in dipteran larvae, 4) share of phytophages in coleopteran larvae communities, 5) average individual biomass, 6) taxonomic richness and the biodiversity (H’), 7) similarity of composition and domination structure of all macrofauna and of dipteran larvae to those in forest communities. The decrease of density of dipteran larvae, particularly of Chironomidae and Sciaridae and the share of saprophages in all macrofauna and in dipteran larvae was also observed. Successional stages of more numerous invertebrate taxa in newly established woodlots are described. Dipteran larvae were the pioneers in colonising newly established shelterbelts, particularly larvae from two families: Chironomidae and Sciaridae. Their combined contribution to the total density of dipteran larvae was 92%.
15
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Ocena wystepowania larw Diptera w glebach Lasu Wolskiego i na przyleglej lace

44%
Chrzan A., Marko-Worlowska M.
Zeszyty Problemowe Postępów Nauk Rolniczych
|
2006
|
tom 515
37-45
Porównywano zespoły larw Diptera w glebach Lasu Wolskiego i przyległej do niego łąki. Na podstawie wyników uzyskanych w trakcie pięcioletnich badań stwierdzono różnice w zespołach tych larw, które dotyczą: 1. zagęszczenia - w 1 m² gleby leśnej zanotowano występowanie 555 osobników, zaś w glebie łąkowej jedynie 129 osobników; 2. stanu biomasy - zdecydowanie wyższą biomasą zespołu (839,51 mg s.m.) charakteryzowały się larwy występujące w glebie lasu. W glebie łąkowej biomasa larw wynosiła 139,64 mg s.m.; 3. średniego ciężaru osobniczego larw - znacznie wyższego w glebie lasu (1,51 mg s.m.) niż w glebie łąki (1,08 mg s.m.); 4. zróżnicowania larw - wyraźnie wyższe na stanowisku łąkowym, gdzie stwierdzono przedstawicieli 17 rodzin. W lesie natomiast wyodrębniono ich 14; 5. struktury dominacji w biomasie - w strukturze troficznej zespołu larw w Lesie Wolskim dominowały formy fitosaprofagiczne (46,6% udziału), zaś w zespole larw w glebie łąki dominowały formy drapieżne (53,8% udziału). Różnice w zespołach glebowych larw Diptera na stanowiskach leśnych w porównaniu z łąkowymi są wykazywane przez wielu autorów, jednak uzyskane w toku badań aż tak znaczne różnice mogą wskazywać na mniejszy wpływ antropopresji na gleby Lasu Wolskiego niż na glebę przyległej do niego łąki. Jednocześnie dominacja biomasy larw drapieżnych w strukturze troficznej zespołu larw na łące świadczyć może o dużej naturalności łąki.
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