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Plant communities in arable fields of the Skierbieszow Landscape Park

100%

Zieminska-Smyk M.

Acta Agrobotanica

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2009

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tom 62

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nr 1

Floristic research on segetal communities was carried out in 2000 on arable fields in the Skierbieszów Landscape Park and its protected zone. Three communities of segetal weeds in cereal crops, and two communities of segetal weeds in root crops were separated in the arable fields of the Skierbieszów Landscape Park. The community Vicietum tetraspermae typicum commonly occurred in cereal crops on brown soils developed from loess soils. The community Echinochloo-Setarietum, which belongs to root crops, was noted in the same habitat. The greatest richness of species was found in Consolido-Brometum and Lamio Veronicetum politae, with the average of 25 species in one record. Both communities were abundant in rare segetal species which are considered to be endangered in our country: Adonis aestivalis, Euphorbia exigua, Lathyrus tuberosus, Muscari comosum, Thlaspi perfoliatum, Veronica polita, Agrostemma githago.

2

Interior of saxicolous lichens on diferent types of rocks as a habitat for microfungal communities in Upper Galilee, Israel

86%

Grishkan I., Temina M.

Acta Mycologica

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2019

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tom 54

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nr 1

3

The lichen biota of Pinus sylvestris under the impact of some stand-related factors: a case study from the South-Eastern part of Zerków-Czeszewo Landscape Park (Wielkopolska-Kujawy Lowland)

86%

Zarabska-Bozejewicz D., Kujawa K.

Acta Mycologica

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2021

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tom 56

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nr 1

4

Microhabitats and oribatid fauna: comparison of 2 sampling approaches

86%

Skubala P.

Biological Letters

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2016

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tom 53

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nr 1

5

Nestedness analysis as a tool to identify ecological gradients

86%

Ulrich W.

Ecological Questions

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2009

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tom 11

Nestedness describes patterns of species composition within continental biotas and among isolated habitats such as islands and landscape fragments. In a nested pattern, the species composition of small assemblages is an ordered subset (a true sample) of the species composition of large assemblages. Nested subsets of species are generated by environmental and ecological gradients, such as habitat quality, carrying capacities of sites, isolation, or fragmentation, that cause ordered sequences of species extinctions and colonization. Therefore nestedness analysis can be used to identify gradients that influence species composition and richness among sites and to identify species that run counter to these gradients (idiosyncratic species). Here I review the use of nestedness analysis to identify such gradients. I also describe how to perform the analysis and which metrics and null models to use for statistical inference.

6

Does red fox Vulpes vulpes affect bird species richness and abundance in an agricultural landscape?

86%

Kujawa K., Lecki R.

Acta Ornithologica

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2008

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tom 43

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nr 2

167-178

The aim of the study (carried out 25 km south of Poznań, western Poland) was to determine the impact of Red Fox on bird abundance on farmland. Bird abundance was studied in the years 1999-2000 and 2005-2007 in three categories of sampling plots: 1) in small woods — with or without active fox dens, 2) along transects — starting from dens and running across arable land, and 3) around points — located at dens and far from them. Thus, variability in bird density was analyzed in relation to the presence/absence of Red Fox (in woods) and to the intensity of Red Fox penetration of crops (approximated by distance from a den). Two groups of bird species were distinguished with respect to their vulnerability to Red Fox predation pressure: 1) potential fox prey, i.e. species nesting on the ground and in low vegetation; and 2) birds not threatened by foxes, i.e. species nesting in tree holes and in tall vegetation. To investigate the relationships between bird distribution and Red Fox dens in woods, a step-wise multiple regression of bird density and species number on woodland structure was first performed. The residuals derived from the model were used to evaluate the impact of foxes by analyzing the differences between woods with and without active dens. Neither the species number nor the bird density differed significantly between woods with and without active dens. The differences in bird density observed between years in woods with or without active dens were not significant, either. No relationship between bird density in crop fields and distance from fox dens was found. The results are contrary to those of earlier studies and show that Red Fox does not affect farmland bird distribution, diversity and abundance, at least in the short term.

7

Humped relationship between herbaceous species richness and biomass reveals a potential for increasing productivity in a temperate desert in Central Asia

86%

Tao Y., Zhou X.-B., Zhang J., Yin B.-F., Wu N., Zhang Y.-M.

Polish Journal of Ecology

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2020

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tom 68

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nr 1

8

Determinants of plant species richness in different wetland types along a hydrological gradient: implication for conservation

86%

Shi J., Ma K., Wang J., Zhang Y., Zhao J.

Polish Journal of Ecology

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2013

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tom 61

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nr 4

The loss of biodiversity caused by wetland degradation is a hot issue in ecology. It is known that hydrological degradation is the primary reason resulting in wetland degradation, but little is known about the relationship between plant species richness and environmental factors in different wetland types along a hydrological gradient. According to the gradient from high to low water level, wetland remnants in the Sanjiang Plain of northeast China were classified into three wetland types, which were permanently inundated marshes (PIM), seasonally inundated marshes (SIM) and wet meadows (WM) respectively. In this paper, we aimed to identify the determinants of plant species richness in the three wetland types and discern the transition of the determinants along a hydrological gradient. Plant species richness as well as area, habitat heterogeneity and resource availability was investigated in 51 wetland remnants, which were composed of 6 PIM, 25 SIM and 20 WM. Averagely, the area of wetland remnants occupied by PIM, SIM and WM was 0.35 ± 0.17 ha, 2.81 ± 2.88 ha and 1.34 ± 1.18 ha respectively. Aggregating the species in each wetland type, there were 67, 244 and 170 species recorded in PIM, SIM and WM. The determinants of species richness varied in different wetland types: standing water depth in PIM, area and water heterogeneity in SIM, and soil fertility and area in WM. With the decreasing water level, the influence of hydrological condition on species richness in the three wetland types declined while the impact of area and soil fertility gradually increased. Thus, hydrological condition was probably responsible for the transition of the determinants of species richness in different wetland types. Moreover, the habitat specialists of wetland would be lost when PIM or SIM degraded to WM. In order to conserve and restore plant diversity, specific measures should be taken including preventing area loss for all wetland remnants, managing the hydrological process for PIM and SIM, and regulating soil nutrient for WM.

9

Geographic distribution of Turkish oaks

86%

Uslu E., Bakis Y.

Dendrobiology

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2012

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tom 67

Distribution of Turkish Quercus L. has a crucial value since Turkey is a transition place between Europe and Asia and located at the meeting point of three phytogeographical regions. To compare the diversity of species and to find the distribution patterns of oaks, species richness of the most current distributions were studied. Relationships of phytogeographical regions and presence of the Anatolian Diagonal relevant to oak distributions were also investigated. Analyses were performed on Davis'grid square system. The highest richness of Quercus species were found at north-western Turkey which were located in the meeting place of Asia and Europe. The lowest richness scores were found at eastern and south-eastern Anatolia. Moreover, latitude, longitude and altitude histograms showed a correlation with species richness. However, the presence of Anatolian Diagonal is partially supported.

10

Species richness relative abundances and habitat use in local assemblages of Sorex shrews in Eurasian boreal forests

86%

Sheftel B. I., Hanski I.

Acta Theriologica. Supplement

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2002

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tom 47

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nr 1

Using a large body of observational data on the occurrence of Sorex shrews in boreal forests, we test two models that predict the structure of small mammal communities along a gradient of increasing habitat productivity. Tilman's (1982) model predicts a humped curve of species richness along productivity gradients. In contrast, we found a linear increase in species richness with increasing logarithm of the pooled density of shrews, which we use as a measure of habitat productivity for shrews. The model of Hanski and Kaikusalo (1989) assumes a trade-off between exploitative and interference competitive abilities, and it predicts that the size structure of small mammal communities should shift from the dominance of small species (superior in exploitative competition) in unproductive habitats to the dominance of large species (superior in interference competition) in productive habitats. Shrew assemblages show such a shift. Though it is not possible to draw definite conclusions about the role of interspecific competition from our observational data, the changing size structure of local shrew assemblages with increasing habitat productivity is a predictable feature of their community structure.

11

Species richness and spatial heterogeneity of spring plankton in a lake with varying morphometry

86%

Budzynska A., Szelag-Wasielewska E.

Acta Agrophysica

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2006

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tom 07

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nr 2[133]

12

Relation between invasive plant and species richness of forest floor vegetation: a study of Impatiens parviflora DC.

86%

Chmura D., Sierka E.

Polish Journal of Ecology

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2006

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tom 54

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nr 3

In 13 forest reserves situated in southern Poland, 68 study plots were established in two regions: the Jurrasic Upland and the Silesian Upland. In these plots, size 10 m × 10 m divided into 100 subplots 1m² each and randomly placed in various forest communities, percentage cover of all species in ground layer was recorded. Relationships between highly invasive alien plant species, Asiatic small balsam Impatiens parviflora DC., and indigenous species, was estimated using various indexes of species richness and diversity. They were: Hill’s numbers (N₀, N₁, N₂), ShannonWiener’s index at the level of a subplot, alpha diversity (species richness within sites), and beta diversity (species richness among sites) at level of a study plot. The subplots with a presence of I. parviflora were compared with those where only native resident species occurred. The study has shown that subplots with the occurrence of I. parviflora are characterized by higher species richness and diversity of native plants independently on vegetation type. The frequency of I. parviflora was negatively correlated with beta diversity of study plots but there was no association with values of alpha diversity. In oak forest, alder carrs and floodplain forests the negative correlation between percent cover of I. parviflora and species richness, as well as cover of the herb layer was observed. The percent cover of I. parviflora was positively correlated with number of native species in beech forest and with their total cover in mixed coniferous forests. However, in natural well-preserved forest phytocoenoses I. parviflora avoids patches characterized by high cover of ground layer species and colonizes empty sites as an additional element of a community.

13

Species - area relationships for sandy beach macrobenthos in the context of intertidal width

86%

McLachlan A., Dorvlo A.

Oceanologia

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2007

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tom 49

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nr 1

The marine species richness (MSR) recorded in 159 sandy beach surveys was analysed in relation to beach width (W). MSR is the number of macrobenthic species collected in a standard intertidal transect survey, excluding insects. Beach width (W) was estimated by dividing the spring tide range [m] by the beach face slope, to give a value in [m]. The relationship between MSR and W was best described by a semilog (exponential) model, which was highly significant: MSR = −5.2+ 10.8 logW. The fit of a power model (MSR = cWz) was also significant. The steep slope of the curve for a power model (z = 0.49) suggests that beaches function as isolated rather than contiguous habitats and that the nature of the habitat becomes more benign as beaches widen. There are some latitudinal effects, with tropical beaches displaying a higher species-area relationship for any beach width than other regions.

14

Differences in abundance and species richness between shrews and rodents along an elevational gradient in the Udzungwa Mountains, Tanzania

86%

Stanley W. T., Hutterer R.

Acta Theriologica

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2007

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tom 52

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nr 3

Small mammals (shrews and rodents) were surveyed along an elevational transect in the Udzungwa Scarp Forest Reserve, in the Udzungwa Mountains, Tanzania. Trap lines and pitfall lines were installed at 600, 910, 1460, and 2000 m a.s.l. In a total of 10341 sample nights (7448 trap-nights and 2893 bucket-nights) 343 specimens (148 shrews, 205 rodents) were captured representing 9 shrew and 14 rodent species for a total of 23 species. While overall species diversity generally increased with elevation, this pattern was not constant for each group sampled. For rodents, both species richness and abundance were lowest at 600 m and greatest at 2000 m a.s.l., and were significantly correlated with elevation. While the highest species number and abundance for shrews was at 2000 m, there was no correlation of these two values with elevation. Rainfall appears to have affected the capture of shrews, but not rodents, and capture success of individual buckets and traps indicated a lack of capture independence. Eastern Arc endemics such asCrocidura desperata Hutterer, Jenkins and Verheyen, 1991 andMyosorex kihaulei Stanley and Hutterer, 2000 were more abundant at 2000 m a.s.l., than at lower elevations. Implications of results of this survey for analyses of future biotic surveys are discussed.

15

Impact of woodland islands on species richness in Jaworzno town and problem of their conservation

86%

Chmura D.

Archiwum Ochrony Środowiska

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2004

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tom 30

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nr 2

16

The response of small mammal communities to cattle grazing on a coastal meadow

86%

Schmidt N. M., Olsen H.

Polish Journal of Ecology

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2003

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tom 51

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nr 1

The response of small mammals to cattle grazing on a coastal meadow with three different grazing intensities was evaluated. Grazed areas tended to hold fewer small mammals than the ungrazed control area, though the variation was high. The negative effect of grazing increased with grazing intensity. Small mammals were caught almost exclusively in patches of high, dense vegetation, and it is suggested that the negative effect of grazing results from the reduced number of such patches. Grazing also affected small mammal species richness, where richness was generally lower in the area of high grazing intensity than in areas with low grazing intensity or without grazing.

17

Fish diversity in different habitats in the streams of lower middle Western Himalayas

86%

Singh J. M., Krishan Tandon K., Kumar Tyor A., Kumar Rawal Y.

Polish Journal of Ecology

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2002

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tom 50

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nr 1

The present study was carried out in the lower middle Western Himalayan streams in the Indian state of Himachal Pradesh of the three river basins namely the Ghaggar, the Sutlej and the Yamuna. The main aim was to study fish assemblage structure/composition, fish diversity in different habitats and the habitat preference of the fishes. The different habitats like pools, riffles, runs and rapids were sampled over a 2 km stretch at all the sites with the help of cast net of 1 cm mesh size having a diameter of I-2 meter on a fixed day every month between mid morning and late afternoon. All the sites when broadly delineated at level-I fall into type - B except site II that is an F - type stream. A total of 23 species belonging to four orders were recorded of which the cyprinids were the most dominant group. According to Shannon-Weaver diversity index, the pool habitat supports greater diversity (H' = 0.72-0.97). Runs (H' = 0.24-0.87) and riffles (H' = 0.22-0.81) have diversity very near to each other at all the sites whereas rapids have significantly lower fish diversity (H' = 0.00-0.58). The pool is the preferred habitat for most of the cyprinid fishes recorded in the present study especially the minnows.

18

Upper Vistula River: response of aquatic communities to pollution and impoundment. X. Oligochaete taxocens

86%

Dumnicka E.

Polish Journal of Ecology

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2002

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tom 50

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nr 2

Zooseston of the Vistula River section almost 340 km long was investigated in the years 1997/98. In 99 samples collected 90 species of rotifers, 16 cladocerans, 9 copepods and other animals belonging to: Harpacticoidea, Oligochaeta, Nematoda, Chironomidae, Odonata, Simulidae, Tardigrada and Coelenterata were found. Multiple regression analysis showed that the number of rotifers is significantly correlated with basic chemical indicators of water trophic state - phosphate, nitrate and nitrite as well as with the number of copepods which are usually predators. The numbers of copepods depends on the availability of possible prey, i.e. rotifers and cladocerans. Multiple regression confirmed known dependence of cladocerans from trophic conditions. Clustering of similarity matrices showed complex structure of sestonic assemblages on rhitral-potamal gradient additionally modified by hydrotechnical constructions. These constructions broke old river continuum. Ordination of sites gave complex pattern not only representing a simple gradient rithral - potamal but also all transient stages caused by hydrotechnical construction (large dam reservoir) or by inflows of polluted waters from the tributaries. Ecological meaning of principal component ordination (PC) for river zooseston assemblages is not simple and might be susceptible of various interpretations.

19

Factors affecting alien and native plant species richness in temperate nature reserves of Northern China

72%

Zhang X., Wang H., Wang S., Wang R., Wang Y., Liu J.

Polish Journal of Ecology

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2017

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tom 65

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nr 4

Understanding the factors affecting the species richness of alien and native plant is a key issue for predicting the spread of alien species and protecting rare and endangered native species in nature reserves. To investigate the factors affecting alien and native species richness in temperate nature reserves of China, we used a database of 25 nature reserves in Shandong Province of northern China, and studied the relationship of alien and native plant species richness with climatic and anthropogenic factors, as well as area and elevation range. We found that most of the nature reserves in Shandong Province have been invaded by alien plant species. The distribution of alien and native species responds to the same climatic factors, and temperature and precipitation exert strong effects on both groups. Alien and native plant species richness are positively correlated. Human activity is more effective for explaining richness of alien than for native species. Simultaneously, human activity has stronger effects on alien herbaceous than on alien woody plants. Our results suggest that native species richness is mainly explained by climatic factors, whereas alien species richness is mainly explained by climatic factors and human activity together.

20

Spider assemblages of hummocks and hollows in a primeval alder carr in the Białowieza National Park – effect of vegetation structure and soil humidity

72%

Stanska M., Stanski T., Gladzka A., Bartos M.

Polish Journal of Ecology

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2016

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tom 64

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nr 4

We studied the species richness, diversity, abundance and guild composition of spider assemblages on the hummocks and in the hollows of the alder carr in the Białowieża National Park. We also assessed the effect of vegetation structure and soil humidity on spiders settled in these two microhabitats. The spiders were collected from 10 May until 27 October 2001 by pitfall trapping. The main factor which differed between the hummocks and the hollows was soil humidity. In the case of vegetation cover we found some differences between the microhabitats but it was particularly evident in the case of litter, which was higher on the hummocks. Spider species diversity was significantly higher on the hummocks than in the hollows, but the number of individuals captured in both microhabitats was similar. The collected spiders belonged to six guilds and the proportion of spider individuals in particular guilds was significantly different between the hummocks and the hollows. The most abundant guild in both microhabitats was ‘ground hunters’ and the most numerous species was Piratula hygrophila. Our analyses showed that soil humidity positively affected the number of spider species and the number of individuals. Sampling date strongly influenced the number of collected species and spider individuals. Vegetation and litter cover did not have a significant impact on the spider assemblages. Our findings suggest that research conducted only on hummocks in the alder carr does not reveal the real structure of spider assemblages.

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