Wyniki wyszukiwania - BazTech

1

Changes in soil nematode community structure following warming and drought manipulations in a grassland mesocosm experiment

Ilieva-Makulec K., De Boeck H. J.

Polish Journal of Ecology

|

2013

|

Vol. 61, nr 1

157--163

EN

The response of soil nematodes to simulated in spring, summer and autumn periods of warming and drought were studied in a grassland mesocosm experiment. The abundance, diversity and some community parameters of nematodes were analysed at different times after the end of the extreme events – 170 days after the spring treatment, 90 days after the summer treatment and 22 days after the autumn treatment. Among studied parameters the abundance of nematode trophic groups, taxonomic richness and diversity were found to be sensitive to changes in the soil system caused by extremes. Our results showed that warming and drought did not cause predictable shifts in nematode communities. Moreover the extremes’ after-effect was not unidirectional with time. The periods of warming and drought induced a positive or negative long lasting influence on nematodes, and the outcome seems to depend on season, the nematode trophic group or even the nematode taxon.

2

Response of soil nematodes to climate-induced melting of antarctic glaciers

Ilieva-Makulec K., Gryziak G.

Polish Journal of Ecology

|

2009

|

Vol. 57, nr 4

811-816

EN

Nematode colonization and establishment of nematode communities on icefree areas created by the recession of Antarctic glaciers were studied on the Antarctic Specially Protected Area (ASPA) No. 128 (Western coast of Admiralty Bay, King George Island, South Shetlands Islands). Soil samples were taken along three transects marked between sea shore and Ecology Glacier, Baranowski Glacier and Windy Glacier and assigned to four age-class intervals: 0-7, >7-29, >29-52 and >52 years after the retreat of the glaciers. Changes in nematode communities, in terms of abundance, diversity and trophic structure were related to the duration of the ice-free period. The abundance of nematodes increased with the age of ice-free areas. The highest numbers of nematodes were found on the sites free of ice for more than 52 years. Taxonomic and trophic diversity of nematodes on these sites was also significantly higher in comparison to the rest sites. Nematode communities on the sites from the first three age-class intervals were poor in genera (up to 6 genera) while on the oldest sites in total 16 genera of nematodes were found. A trend of increasing the number of nematode trophic groups along the age classes was also apparent - from community of nematodes belonging to only two trophic groups (bacterial and fungal feeders) on younger ice-free sites to more complex community of nematodes (belonging to five trophic groups), at the oldest sites.

3

Nematofauna of the shelterbelts in the agricultural landscape

Wasilewska L.

Polish Journal of Ecology

|

2004

|

Vol. 52, nr 2

99-113

EN

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 maturityindex 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 closes to the shelterbelt.

4

Post-drainage secondary succession of soil nematodes on fen peat meadows in Biebrza Wetlands, Poland

Wasilewska L.

Polish Journal of Ecology

|

2002

|

Vol. 50, nr 3

269-300

EN

After the drainage of fens and their permanent use as meadows, peat-forming process is being replaced by moorshing (mucking) process (mineralization and humification of peat), and then by turf-forming process. Secondary succession of soil nematodes was examined by using the chronosequence of meadow sites (period I: 1978-1983) and also by analysing the same sites 15-17 years later (period II: 1994-1997). The analysis was focused on the taxa (genera) of nematodes and on 19 to 29 parameters describing the community as total density, density of trophic groups, diversity indices and maturity indices. The pattern of successional changes was obtained for periods from 2 to 117 years after drainage. Natural not-drained fens were used for comparison. Soil structure and soil processes occuring over the time considered can be characterized as follows: soil moisture (by weight) 80-52% total soil porosity 90-77%, bulk density 0.16-0.44 (to 0.92) g cm^-3, total C content in soil 47-7% total N content in soil 4.4-0.5%, ranges in the sequence from Mt I (poorly moorshified soils) to Mt III (strongly moorshified soils). In natural fens, soil moisture was 80%, soil porosity 90%, bulk density 0.15-0.35 g cm^-3, and peat-forming processes (Pt) were continued. As compared with natural fens, drainage and management of fens was associated with increasing density of total nematodes and their components such as bacterivores, fungivores, facultative plant feeders, obligate plant feeders, omnivores, and predators. In drained fens the density of nematodes declined with succession with the exception of omnivores. The increase in the density of omnivores was positively correlated with the number of years after drainage (r=0.48, P<0.01). The indices of taxa diversity and maturity indices were postively correlated with years after drainage (P<0.001-0.05). In natural fens, ranges of density of all trophic groups were lower, and maturity indices higher than in drained peat meadows. The The mechanisms driving the first stage of succession in nematode communities (until about 30 years after the drainage of fens) seem to be tolerance to the droughts and to the excess of nitrogen what was accompanied with higher density of herbivores (mainly Paratylenchus). In later stages, interspecific competition is likely to play a more important role. Also a statistically significant relation was found of some taxa and parameters to peat type.

5

The effect of macroarthropods patrolling soil surface on soil nematodes : a field experiment in a mown meadow

Wasilewska L.

Polish Journal of Ecology

|

2000

|

Vol. 48, nr 4

327-338

EN

A field experiment was designed to estimate the effect of soil surface patrolling by macroarthropods on organic matter content in soil. One of the components of this experiment was the soil nematode community - density, trophic and dominance strukture, the diversity and maturity indices. These parameters were compared between two types of mesocosms: accessible and inaccessible to macroarthropods. The experiment was performed under natural environmental conditions and did not reduce the diversity of the biota characteristic of the ecosystem. Most parameters of nematodes did not vary significantly between mesocosms. Differences between mesocosms observed over the 5-month period of each of the two experiments (1992 and 1993) concerned mainly, bacterivorous nematodes and, within this trophic group, colonizers. The densities of the taxon Rhabditis s.l. were statistically higher in the mesocosms accessible to macroarthropods, and the proportion of colonizers (r-strategists s.l.) among bacterivorous nematodes was also higher.

6

Effect of temperature on the soil nematode Cephalobus persegnis in a laboratory culture

Makarevskaja Z.

Polish Journal of Ecology

|

1998

|

Vol. 46, no 2

197-205

EN

Soil nematodes Cephalobus persegnis (Bastian 1865) originating from a laboratory culture maintained at 20 stopni C cultured for three successive generations at 15 stopni C, 21 stopni C, or 15/21 stopni C for 12 hours in each temperature. Transfer of the nematodes to 15 stopni C markedly depressed their fecundity and growth of F1 worms. In next generations fecundity restored while size of the nematodes increased significantly. Similar though less pronounced changes were observed also at 15/21 stopni C. No marked changes were found at 21 stopni C. The temperature the nematodes were cultured at did not influence their respiration rate measured at 21 stopni C. The latter depended on the weight of the nematodes.

7

Wpływ metali ciężkich zawartych w odpadach z huty ołowiu na zespoły nicieni glebowych

Ilieva-Makulec K., Dmowska E.

Chemia i Inżynieria Ekologiczna

|

1998

|

Vol. 5, nr 8-9

707-711

PL

Badano działanie następcze metali ciężkich Cd, Zn i Pb na nicienie glebowe po wapnowaniu. Badania prowadzono na poletkach doświadczalnych wapnowanych trzykrotnie wapnem z kopalni węgla brunatnego w dawce dwa razy większej niż hydrolityczna kwasowość gleby (2Hh), wapnowanych dwukrotnie i trzykrotnie odpadami z huty ołowiu (2h) oraz niewapnowanych. Analiza gleby przeprowadzona w roku pobierania prób, tj. wiosną 1996 r., wykazała różnice w zawartości metali ciężkich w glebie badanych poletek. W glebie wapnowanej trzykrotnie odpadami z huty ołowiu, najbardziej skażonej metalami ciężkimi, zawartość Cd i Zn po czterech latach po wapnowaniu była bliska ilości przewidzianej dla gleb o podwyższonym stopniu skażenia. W glebie tej stwierdzono istotnie niższą liczebność nicieni bakteriożernych, grzybożernych i roślinożernych oraz mniejszą różnorodność rodzajową nicieni niż w pozostałych glebach.

EN

The effect of heavy metals Cd, Zn and Pb on soil nematodes was investigated after liming. Some of the experimental fields were treated three times with lime (2Hh) from the brown coal mine or twice or three times treated with lime waste (2Hh) from lead-works and other were untreated. Chemical analysis of soil from the test fields in the year of sampling, spring 1996 showed some differences in heavy metal contains. In soil with the highest content of Cd, Pb and Zn (three times repeated usage of lime waste from lead-works) the abundance of bacterial-feeding, fungal-feeding and plant-feeding and also genera diversity were significant lower then in the other soils.