Andrzej Kruk

University of Lodz · Department of Ecology and Vertebrate Zoology

The Serteyka River valley is one of the most important archaeological localities in North- Western Russia. The State Hermitage Museum has conducted research in Serteya since the 1970s. The pile-dwelling remnants located within the Great Serteya Palaeolake Basin (GSPB) are the most prominent excavation. The investigation using precise underwater tec...

Urbanization directly affects the ecological status of streams and rivers: Their beds and drainage basins are often heavily transformed and their habitat conditions disturbed. The aim of the study was to evaluate the extent of human impact in streams in the city of Łódź, Central Poland (~700,000 inhabitants), by pattern recognition analysis of bent...

Abstract

The Warta River (795 km long) is the largest tributary of the Odra (Oder) River. This study presents results from one of the best-documented long-term monitoring projects in Poland, based on three periods of electrofishing: 1986–88 (T1), 1996–98 (T2) and 2011–12 (T3). After decades of severe point-source pollution, water quality has been improving...

Water pollution from industrial Metro Łódź (ML), Poland, made the Ner River almost fishless in its middle-lower course for most of the 19th and 20th century. The new sewage treatment plant of ML and reduction of industry have caused pollution abatement there since the 1990s. As a result, the Ner became repopulated, which was shown by fish samples c...

The aim of the study was to assess whether ichthyofauna variability follows the natural downstream gradient or the degradation gradient, and to assess the bioindication potential of fish zonation. The study was conducted along the entire length (795 km) of the lowland Warta River, Poland, wherein the complexity of the ecotone zone and availability...

The Warta River (795 km long) is the largest, right side tributary of the Odra (Oder) River. The study presents results from one of the best-documented long-term monitoring projects in Poland based on four terms of electrofishing: 1963–66, 1986–88, 1996–98 and 2011–12, conducted in the upper Warta. The Warta River underwent human-induced modificati...

We applied two widely-used methods for data partitioning — constrained incremental sum-of-squares (CONISS) and Optimal Partitioning (OP) along with two supplementary methods, a Kohonen artificial neural network (self-organising map, SOM) and the indicator value (IndVal) index, for the quantitative analysis of subfossil chironomid assemblages from a...

The recognition of long-term patterns in the seasonal dynamics of Daphnia longispina, Leptodora kindtii and cyanobacteria is dependent upon their interactions, the water temperature and the hydrological conditions, which were all investigated between 1999 and 2008 in the lowland Sulejow Reservoir. The biomass of cyanobacteria, densities of D. longi...

Database of the self-organizing maps (SOM). (DOCX)

The 412 sampling terms assigned to the 24 SOM output neurons. The code for each term consists of two digits for the day, two digits for the month and two digits for the year of sampling, e.g., 190799 = 19th of July 1999. (TIF)

Self-organizing maps of different calculated sizes, quantization and topographic errors and the number of empty neurons (which were not appreciated). (DOCX)

The Warta River is a tributary of the Odra (Oder) River. It is 795.2 km long. In 1986 the large Jeziorsko dam reservoir was constructed in the 306th km of its course. In the late 1980s, the river pollution assumed its highest level and stopped increasing as the former political system collapsed and many industrial plants went bankrupt. Unified fis...

This paper presents a palaeoenvironmental reconstruction of theWilczków fen (central Poland). The fen developed in an inactive valley at the onset of the Holocene (~11 ka BP) and peat accumulation lasted until 5.7 ka BP. Multiproxy reconstructions were made on the basis of palaeobotanical, cladoceran, chironomid, beetle and geochemical analyses. A...

The study was conducted from 2000 to 2003 in the tailwater of the Drzewieckie Lake, an artificial reservoir in Central Poland. Short-term peaks in water flow were generated for the purpose of the operation of a whitewater slalom canoeing track built just downstream of the dam. In 2002, the reservoir was drawn down. The patterns in habitat samples w...

From May to August 2004, the available food base and diet of two cyprinid species, eurytopic roach, represented by 75 small specimens, and rheophilic dace, represented by 37 small specimens, were investigated in seasonal patches of submersed aquatic macrophytes (SAM) in the impounded lowland Warta River, Poland. The aim of the study was to recogniz...

Fish and lampreys were sampled by electrofishing in the Pilica River tributaries (the Vistula catchment, Poland) in 1992–1994 and 2003–2005. The patterns in fish assemblages were recognized on the basis of fish biomass using Kohonen's self-organizing map (SOM) technique, combined with the indicator values (IndVal) for assessment of associations of...

Because lately the low bioindicative value of tolerant species from different taxonomic groups is often questioned, in this study, we hypothesized that tolerant diatoms may be used for effective temporal assessments of human pressure. We tested this on the lowland Bzura River in central Poland, on 156 diatom samples (DSs) from two study periods of...

Floodplain forests are specific, dynamic forest ecosystems rich in species, sited in river valleys. Their quality and existence depends on the flooding regime of the river. In the Bzura River valley (Vistula tributary, Poland) these forests have been subject to human impact by deforestation and melioration. Since 1823, the Bzura River bed has been...

Kohonen self-organizing maps (SOMs) are unsupervised Artificial Neural Networks (ANNs) that are good for low-density data visualization. They easily deal with complex and nonlinear relationships between variables. We evaluated molecular events that characterize high- and low-grade BC pathways in the tumors from 104 patients. We compared the ability...

From June to August 2004, the available food base and the diet of 52 small perch and 38 ruffe specimens were investigated in a macrophyte habitat in the Warta lowland alluvial river, Poland, downstream from a large dam reservoir. The river bed was covered by large patches of Potamogeton spp. To recognise patterns in fish alimentary tracts’ contents...

1. In the Kampinos National Park (Poland), which is a UNESCO Biosphere Reserve, 47 caught per unit effort samples of Chrysididae were collected in 2000–2006. The aim of the study was to identify the factors promoting the diversity of this rarely studied group of parasitic wasps. 2. A total of 722 specimens belonging to 37 species were recorded, inc...

Electrofishing was conducted along the Pilica River, the biggest West tributary of the Vistula, Poland. This paper presents a comparison between the 1990s (1994–1995, 63 sites) and 2000s (2003–2005, 64 sites), that is, because the water quality started improving after 1989. In the Pilica, there is an increased risk of masking relationships between...

Question Can a K ohonen's self‐organizing map, which is robust to non‐linear relationships between variables and their non‐normal distributions, be effective in patterning the data on plant communities investigated with the classical B raun‐ B lanquet phytosociological method based on the ordinal scale? Does the application of the self‐organizing m...

Pyrophilous macrofungi (PM) are a narrowly specialised group appearing exclusively in plant communities recently destroyed by fire. Their significance has hitherto been studied only for vegetation destroyed over large areas, while in small areas of fire, i.e., microhabitats they are viewed as independent components of the community linked only to t...

a b s t r a c t This fish community survey conducted in the impounded Warta River at a backwater (AB) and a tail-water (CD) sites is a continuation of our former study (1985–2002). Similarly as the former, the present analysis concerns the pre-impoundment period (1985–1987) and the post-impoundment period, but the latter period is eight years longe...

From 2000 to 2006 a total of 52 CPUE samples of spider wasps (Hymenoptera: Pompilidae) were collected in the mosaic landscape of the Kampinos National Park (Poland), which is a UNESCO Biosphere Reserve. The hypothesis tested was that both pompilid species richness and abundance is positively associated with spatial heterogeneity. The patterns in sp...

Export Date: 24 August 2012, Source: Scopus, Article in Press

Electrofishing was conducted along the Pilica River, the biggest West tributary of the Vistula, Poland. This paper presents a comparison between the 1990s (1994–1995, 63 sites) and 2000s (2003–2005, 64 sites), that is, because the water quality started improving after 1989. In the Pilica, there is an increased risk of masking relationships between...

Electrofishing was conducted along the Pilica River, the biggest West tributary of the Vistula, Poland. This paper presents a comparison between the 1990s (1994–1995, 63 sites) and 2000s (2003–2005, 64 sites), that is, because the water quality started improving after 1989. In the Pilica, there is an increased risk of masking relationships between...

The A148T polymorphism of CDKN2A gene is observed in various neoplasms with the incidence rate of 3-35%, however, rather little is known either about the frequency of its occurrence or of its significance in urinary bladder carcinoma. DNA was isolated from blood of 156 patients with urinary bladder carcinoma (130 men). In histopathology, 84 cases w...

Wild passerines, especially tits, utilize snail shells as the main source of calcium necessary for laying females to construct egg shells. This research found that the two study areas, representing two habitat types - a mature deciduous forest and a human-disturbed parkland - are inhabited by different snail assemblages: both species richness and d...

The samples were analysed with the Cholnoky (1968) method, which consists in counting and simultaneous identifying 400 diatom frustules in each constant slide. The remaining taxa were then identified under the whole slide's cover glass (18 mm/18 mm) according to Rakowska (2001). Identification of alga was carried out according to Krammer's and Lang...

The aim of this study is to assess the response of Trichoptera in a patchy tailwater stretch of the Drzewiczka River (Poland) to dam removal as compared to the previous pulse discharge disturbance. The study was carried out in the river at the end of a whitewater slalom canoeing track located downstream of the dam reservoir called Drzewieckie Lake...

The section of the lowland Narew River within Polish borders (432km long) flowing between two big reservoirs, and its tributaries were selected for the study. At 321 sites a total of 49,675 fish and lamprey specimens, representing 36 taxa, were collected. The sites were classified using the Kohonen self-organizing map (SOM) on the basis of fish and...

The distribution and abundance of fish collected in 1996–1998 are compared in three river sections X, Y and Z in the 808-km-long Warta River, Poland. The upper section, X, was least human-modified, the middle section, Y, was the most polluted by industry and regulated, and the downstream section, Z, was moderately disturbed. The differences between...

Cited By (since 1996): 4, Export Date: 24 August 2012, Source: Scopus

The paper assesses the impact of the Jeziorsko dam reservoir on chironomid assemblages and selected environmental factors in the Warta River, Poland, by means of patterns recognized with the self-organizing map (SOM, Kohonen unsupervised artificial neural network). Over 1988–1996, in four annual cycles, a total of 233 monthly samples were col-lecte...

Sensitiveness to the overall influence of the river channel regulation, impoundment and pollution was studied for 12 non-obligatory riverine (NOR) fish species in the Warta River, Poland, over the period of 1963–1998. Their total abundance has not considerably changed unlike the structure of their aggregation, which was revealed by a self-organizin...

An exemplary classification of otolaryngological data with use of the Kohonen artificial neural network is presented along with an evaluation of grouping effectiveness. The study was based on 220 patients with otosclerosis, including 184 women and 36 men, aged 16-68, operated at the Otosurgery Department, Medical University of Lodz in 1984-1992. Th...

Impoundment impact on fish assemblage structure was investigated in the dammed middle course of the Warta River. A backwater site (AB) was located 2 km upstream of the Jeziorsko Reservoir, and a tailwater site (CD) 1.5 km downstream of the dam. Both sites were studied for 3 years in the pre-impoundment period (1985–1987) and 15 years after damming...

Export Date: 24 August 2012, Source: Scopus

The study of fish assemblages in the Pilica River has not yet been undertaken despite data being available for various reaches. At the beginning we tried to analyse the data by detrended correspondence analysis (DCA), but obtained ordinations were not clear. On the two-dimensional scatterplot, sites from the main channel and sites from lower course...

Four oxbow lakes and two neighbouring sections of their parent Warta River (Odra River system, Poland) were sampled to investigate differences in fish assemblages between habitats in 1999–2000. Additional comparisons were made with 12 other oxbow lakes in this section of the river that were sampled 30–40 years ago. Downstream of a man-made reservoi...

The history of the decline in barbel abundance and distribution in the Warta River system is described. This fish, formerly widely distributed in the Warta and its larger tributaries, is nowadays confined mainly to the upper Warta, where it is still relatively abundant, although not common in the fish community. The human alterations of the riverin...

In the upper course of the 808 km long Warta River (a tributary of the Odra River), changes in population parameters (stability of occurrence, numbers and biomass) of diadromous European eel Anguilla anguilla (L.) and vimb Vimba vimba (L.), and potamodromous nase Chondrostoma nasus (L.) and barbel Barbus barbus (L.) were studied over the period 196...

Export Date: 24 August 2012, Source: Scopus

Export Date: 24 August 2012, Source: Scopus

Export Date: 24 August 2012, Source: Scopus

Recruitment, movement and body lengths of 0+ fish were investigated in three oxbow lakes (OL) and two neighbouring sections of the Pilica River (19962000), and also in four OLs and two neighbouring sections of the Warta River (19982000). More juveniles were sampled in OLs than in their parent rivers, especially much more in the Warta River system,...

A long-term study (1985-1999) conducted at backwater and tailwater sites of a large reservoir located in the middle course of the 808 kin long Warta River (Poland), showed that not only obligatory riverine species suffer from the effect of the dam. Facultative riverine eel, burbot, wels and pike considerably decreased in number and standing crop, i...

Three oxbow lakes of the alluvial Pilica River, each in a different stage of connection with the channel, display different levels of importance for maintaining fish diversity in the catchment and as moderators of climatic stress. During a five year investigation, from 1996 to 2000, following a series of hot summers and minimal river flows, heavy f...

Abstract – The fate of obligatory riverine fish species (rheophils), which are the objects of anglers' exploitation (chub –Leuciscus cephalus, nase –Chondrostoma nasus, barbel –Barbus barbus, gudgeon –Gobio gobio), and brown trout (Salmo trutta m. fario) and grayling (Thymallus thymallus) (in the Gwda River basin only), were investigated in large a...

Comparisons were made between fish dominance and community structure in three oxbow lakes and their parent Pilica River (the Vistula catchment) using samples from 1971, and 1996-98. Time-related changes were recorded both in the oxbow lakes' morphology, their connection with the main channel and presence/absence of fish species and their dominance...

Cited By (since 1996): 12, Export Date: 24 August 2012, Source: Scopus