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Multiple Parallel Ordinations: the Importance of Choice of Ordination Method and Weighting of Species Abundance Data

agricultural landscapes. Agric. Ecosyst. & Environ. 114: 270-286. Brown, J.H. 1984. On the relationship between abundance and distribution of species. Am. Nat. 124: 255-279. Buckley, H.L. & Freckleton, R.P. 2010. Understanding the role of species dynamics in abundanceoccupancy relationships. J Ecol. 98: 645-658. Cao, Y. & Epifanio, J. 2010. Quantifying the responses of macroinvertebrate assemblages to simulated stress: are more accurate similarity indices less useful? Meth. Ecol. Evol. 1: 380-388. Clarke, K

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Abundance dynamics of mites (Acari) in the peatland of ‘Linie’ Nature Reserve, with particular reference to the Gamasida

. w zadrzewieniu śródpolnym zdominowanym przez dąb bezszypułkowy w okolicach Turwi [The dynamics of mites (Acari) abundance in 1992 in an oak spinney in an agricultural landscape near Turew]. Zesz. Nauk. ATR Bydgoszcz, Zootech., 26: 133-145 (in Polish). Seniczak S., Klimek A., Górniak G., Kaczmarek S. 1988. Dynamika liczebności roztoczy (Acarida) w płatach słonorośli w rejonie oddziaływania Janikowskich Zakładów Sodowych w 1986r. [Seasonal variation of abundance of mites (Acarida) in halophyte patches in the region of Janikowo Soda Factory

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Influence of crop species and edaphic factors on the distribution and abundance of trichoderma in alfisol soils of southern India

3, 19-28. CHAVERRI, P., SAMUELS, G. J., STEWART, E. L., 2001: Hypocera virens sp. nov., the teleomorph of Trichoderma virens. Mycologia 93, 1113-1124. COOK, R. J., BAKER, K. F., 1983: The nature and practice of biological control of plant pathogens. St, Paul, American Phytopatological Society, New York. DANIELSON, R. M.,DAVEY, C. B., 1973: The abundance of Trichoderma propagules and the distribution of species in forest soils. Soil Biology and Biochemistry 5, 485-494. DOMSCH, K. H.,GAMS,W.,ANDERSON, T

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Optimum sample size to estimate mean parasite abundance in fish parasite surveys

://cran.r-project.org/web/packages/DTK/ M arques , J.F., C abral , H.N. (2007): Effects of sample size on fish parasite prevalence, mean abundance and mean intensity estimates. J. Appl. Ichthyol ., 23: 158 – 162. DOI: 10.1111/j.1439-0426.2006.00823.x M ouillot , D., C ulioli , J.-M., L epretre , A., T omasini , J.-A. (1999): Dispersion statistics and sample size estimates for three fish species ( Symphodus ocellatus, Serranus scriba and Diplodus annularis ) in the Lavezzi Islands Marine Reserve (South Corsica, Mediterranean Sea). Mar. Ecol. , 20(1): 19 – 34. DOI: 10.1046/j.1439

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Linear Transect Surveys of Abundance and Density of Cetaceans in The Area Near the Dzharylgach Island in the North-Western Black Sea

, F. A., Kilgour, C., Lander, M., Fitzgerald, G. D. 2014. Studies for Carrying Out the Common Fisheries Policy: Adverse Fisheries Impacts on Cetacean Populations in the Black Sea. Final report to the European Commission. Brussels, 1-347. Buckland, S. T., 2004. Advanced Distance Sampling: Estimating Abundance of Biological Populations. Oxford University Press, New York, 1-416. Buckland, S. T., Anderson, D. R., Burnham, K. P., Laake, J. L., Borchers, D. L., Thomas, L., 2001. Introduction to Distance Sampling: estimating Abundance of

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Diversity and Abundance Patterns of Amphibians in Rehabilitated Quarries of Bamburi Near Mombasa (Kenya)

ABSTRACT

Amphibians are sensitive to changes in the environment and are, therefore, excellent indicators of success in restoring degraded habitats. As such, a clear understanding on how amphibian populations respond to changes in the environment is required. In order for conservationists to establish if the declining trends are changing, biodiversity recovery studies are essential especially in reclaimed habitats. This study focused on the recovery of amphibians, particularly on frogs, in reclaimed quarries of the Bamburi Cement Plant near Mombasa whereby the diversity, species abundances and composition at different stages of quarry re-establishment were assessed.

The study area was divided into three zones based on the 13-year interval since the beginning of the rehabilitation process. Transect surveys and time-constrained search and size method were used for sampling 20 randomly selected sites. Sampling was done during the rainy and the dry seasons, with searches conducted between 900 and 1,600 hours during the day and between 1,800 to 2,100 hours at night. Recording of basic morphological data of collected specimens was done in the field to aid in grouping specimens before voucher materials were preserved in 10% formalin and stored in 70% alcohol. Further identifications and confirmations matching specimens to species were carried out using specialized classification keys from the National Museum of Kenya.

Twelve species were encountered across the three zones, with Ptychadena anchietae and Phrynobatrachus acridoides, respectively, the most abundant. It was also noted that amphibian diversity across the quarries was independent of the age of ecological reestablishment (r = -0.5). This is indicated by the higher amphibian diversity in the south and north quarries (N = 1050 and 506 respectively) despite their relatively younger age since reestablishment compared to the central quarry (N = 438). Lower diversity in the central quarry, although the oldest, may be largely attributed to human disturbance. Additionally, exotic plantations across the study area are poor in species since they are monocultures and, thus, not heterogeneous enough to support higher anuran diversity. Since amphibians act as one of the best measure of environmental health, rehabilitation process in the quarries need to embrace mechanisms that support maximum biodiversity recovery such as replanting of more indigenous tree species as opposed to only exotic monocultures.

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The effect of habitat conditions on the abundance of populations and selected individual and floral traits of Impatiens glandulifera Royle

Abstract

The effect of site conditions on the abundance of populations of I. glandulifera, selected individual features (height and width of stems, number of whorls and side branches, flower production), and floral traits (total length of flowers, length and width of lower sepal, spur length) were investigated in years 2013-14. Observations were conducted on fallow land, at roadsides, along riverbanks and edges of a riparian forest as well as in a willow thicket and a riparian forest inside located in the Vistula River valley in southern Poland. In these stands, taken successively, light availability gradually diminished, while plant canopy height and soil moisture increased. The low abundance of the population on the fallow land may have been caused by low soil humidity triggering seedling mortality, whereas the low abundance in the interior of the riparian forest may have been due to seasonal water stagnation hampering the development of offspring. The increasing values of individual traits from the fallow land to riparian forest edge might be linked to growing lateral shade, whereas the much lower values in the willow thicket and forest interior might be caused by full shade. Individuals growing on the fallow land, at roadsides, and along riverbanksproduced flowers with small total lengths and large lower sepals and spurs, whereas individuals occurring in willow thickets and riparian forests showed opposite tendency. The considerable stem dimensions and substantial production of large flowers may augment chances for successful resource capture and pollinator visits in open sites, while the reduced size of individuals and moderate production of small flowers may be sufficient for the maintenance of populations in closed habitats

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Analysis of abundance and quality characteristics of individuals in a regenerated Northern red oak (Quercus rubra L.) stand

Abstract

A 40-year-long research of the influence of diverse silvicultural managements on Northern red oak (Quercus rubra L.) stand development has been performed in Šahy Forest District (Veľký Šomoš locality). Currently (stand age 85 years) the stand regeneration has begun. A shelterwood-strip-system of regeneration with a short regeneration period (10 or 15 years) is recommended. During the silvicultural selection of trees we examined quantitative biometrical characteristics and qualitative characteristics. We found out that on the plot with the seed cut 20% of individuals were bent or created vegetative sprouts, 10% of trees had a fork crown and 7% were mechanically damaged. 41% of trees were undamaged. On the plot with the clear cut,up to 47.5% of trees (including chosen trees) were without degradations marks. The number of bent trees (10%) was lower compared to the plot with the seed cut, but the number of trees with vegetative sprouts was higher (26%). Statistical analysis based on χ2 test revealed that the differences in the abundance of qualitative characteristics between the investigated regeneration elements were statistically insignificant. In Europe, Northern red oak is a tree species of the future, so it is necessary to pay more attention to this species.

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Aquatic Heteroptera of Great Rivers of the Ukrainian Steppe Zone and Seasonal Changes of Abundance and Biomass

Abstract

Aquatic Heteroptera of Great Rivers of the Ukrainian Steppe Zone and Seasonal Changes of Abundance and Biomass. Grandova, M. A. - Aquatic Heteroptera are one of the important components of water biocoenoses. During the study of the great rivers of the Ukrainian continental steppe zone 34 species were found, among them Sigara mayri (Fieber, 1860), a new species for Ukraine. Cymatia bonsdorffi i (C. R. Sahlberg, 1819) and Hydrometra stagnorum (Linnaeus, 1758) are recorded in the Ukrainian continental steppe zone for the first time. During the whole year the aquatic Heteroptera taxocenoses of all the concerned objects create the indivisible complex, which basis is formed by inhabitants of inundated reservoirs. Th e highest abundance is observed in the reed bed lakes in the middle of July, aft er the hatching of the second generation nymphs of the polyvoltine species, the maximum of biomass is observed in October in the reed bed lakes, where Nepomorpha gather for overwintering.

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An Indigenous Species, Dreissena polymorpha (Pallas, 1771) (Mollusca, Bivalvia), as an Invader in Lake Büyük Akgöl

., 1998 – Quantifying mechanisms for Zebra mussel effects on benthic macroinvertebrates: organic matter production and shellgenerated habitat, Journal of North American Benthological Society , 17, 81-94. 41. Strong E. E., Gargominy O., Winston F. P. and Bouchet P., 2008 – Global diversity of gastropods (Gastropoda; Mollusca), in freshwater, Hydrobiologia , 595, 149-166. 42. Stuckey R. L. and Moore D. L., 1995 – Return and increase in abundance of aquatic flowering plants in Put-in-Bay Harbor, Lake Erie, Ohio, Ohio Journal of Science , 95, 261

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