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Roadside Habitats : The Impact of Salinization on the Occurrence, Growth and Reproduction of Two Weed Species Echinochloa crus-galli and Digitaria sanguinalis

Nováková Markéta, Šerá Božena, Cudlín Pavel

Polish Journal of Ecology

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2019

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Vol. 67, nr 3

186--193

EN

The specific conditions in habitats in the immediate vicinity of roads provide a suitable environment for noxious weeds and invasive species that spread through them to the landscape. Echinochloa crus-galli and Digitaria sanguinalis are problematic weeds of wide-row crops. The field experiment focused on the impact of the roadside habitat salinization on the occurrence, growth and reproduction of these two species. Quantitative vegetative and generative characteristics of the plants were determined. Measurements were carried out at three distances from the edge of the road and on control plots. The results showed that the growth and reproduction of E. crus-galli and D. sanguinalis occur in the period when the values of soil environmental variables correspond to values of non-saline soil according to the criteria for soil salinity assessment. Despite this fact, the average salinity of soil along roadside was still higher than in soil of further distances and we found these levels of salinity to be well tolerated by the study species. Therefore, we conclude that roadsides with the same or higher salt content represent a suitable location for the occurrence and reproduction of E. crus-galli and D. sanguinalis, thus being temporary locations that enable their further spreading to the countryside.

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Chamaepinnularia thermophila (Bacillariophyceae) : synonymy with Navicula tongatensis Hustedt and update of its geographic distribution and ecology

Lai Giuseppina Grazia, Ector Luc, Padedda Bachisio Mario, Lugliè Antonella, Wetzel Carlos Eduardo

Oceanological and Hydrobiological Studies

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2019

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Vol. 48, No. 2

105--115

EN

Chamaepinnularia thermophila is a small and poorly known diatom species. After the first description from a hot spring in Guadalupe in 1952, its presence appeared to be limited to a few other springs of the French Antilles. The objective of this study is to report new information on aspects of taxonomy, distribution and ecology of this species. Accurate analysis under light and scanning electron microscope of the material collected on different substrates (cobbles, macrophytes and fine sediments) from a thermo-mineral spring of Sardinia (Italy) allowed us to document the first record of the species in the Mediterranean area. Furthermore, the comparison with Navicula tongatensis from Hustedt's original material, carried out because of their similarity, revealed identical morphological characteristics suggesting their consequent synonymy. Based on the information available in the literature and our data, C. thermophila is a rare species present mainly in tropical areas, in thermal springs with alkaline pH, medium to high conductivity and low to moderate nutrient content. The occurrence of the species at sites with very different environmental characteristics seems unusual, but it could indicate a broader ecological range. This study contributes to the standardization of the nomenclature used for this species so far and provides the first framework on its global geographic distribution and ecology.

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Distribution of Crataegus (Rosaceae) along a gradient of anthropogenic influence

Oklejewicz K., Chwastek E., Szewczyk M., Bobiec A., Mitka J.

Polish Journal of Ecology

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2013

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Vol. 61, nr 4

683--691

EN

The impact of land use intensity on the taxonomic composition of hawthorns in four regions of south-eastern Poland was investigated. As a result of different human settlement histories, two of the regions are 54–64% forested nowadays, and the remaining two regions are 70–78% transformed into arable land. Numerical analysis and Monte Carlo permutation tests showed that the purely geographical component of the species distribution, linked with the land use intensity, was statistically significant (1.97%, P = 0.002), as well the pure site component (1.17%, P = 0.010). The human-induced opening of the landscape promotes Crataegus monogyna. Forests are occupied by C. laevigata, C. rhipidiphylla, C. rhipidophylla Gand. var. lindmanii and the hybrid C. × macrocarpa (C. rhipidophylla × C. laevigata); on forest edges the hybrid C. × media (C. monogyna × C. laevigata) tends to occur. Crataegus × subsphaericea (C. monogyna × C. rhipidophylla) is rare and tends to occur in thickets, and a triple hybrid C. monogyna × C. rhipidophylla × C. laevigata colonizes recently abandoned fields. Hybridization seems to be an efficient evolutionary strategy of hawthorns in the face of human-induced transformations of the landscape.

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Habitat modelling limitations - Puck Bay, Baltic Sea - a case study

Węsławski J.M., Kryla-Straszewska L., Piwowarczyk J., Piwowarczyk J., Urbański J., Warzocha J., Kotwicki L., Włodarska-Kowalczuk M., Wiktor J.

Oceanologia

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2013

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No. 55 (1)

167-183

EN

The Natura 2000 sites and the Coastal Landscape Park in a shallow marine bay in the southern Baltic have been studied in detail for the distribution of benthic macroorganisms, species assemblages and seabed habitats. The relatively small Inner Puck Bay (104.8 km2) is one of the most thoroughly investigated marine areas in the Baltic: research has been carried out there continuously for over 50 years. Six physical parameters regarded as critically important for the marine benthos (depth, minimal temperature, maximum salinity, light, wave intensity and sediment type) were summarized on a GIS map showing unified patches of seabed and the near-bottom water conditions. The occurrence of uniform seabed forms is weakly correlated with the distributions of individual species or multi-species assemblages. This is partly explained by the characteristics of the local macrofauna, which is dominated by highly tolerant, eurytopic species with opportunistic strategies. The history and timing of the assemblage formation also explains this weak correlation. The distribution of assemblages formed by long-living, structural species (Zostera marina and other higher plants) shows the history of recovery following earlier disturbances. In the study area, these communities are still in the stage of recovery and recolonization, and their present distribution does not as yet match the distribution of the physical environmental conditions favourable to them. Our results show up the limitations of distribution modelling in coastal waters, where the history of anthropogenic disturbances can distort the picture of the present-day environmental control of biota distributions.

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Application of Isotachophoresis for Determination of Anionic Forms of Phosphonic Acids

Górecki H., Szczygieł B, Drela I.

Polish Journal of Chemistry

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2004

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Vol. 78 / nr 9

1691-1702

EN

Using a capillary electrophoresis analyser, the concentrations of anionic forms of 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTC) and N-trismethylenephosphonic acid (NTMP) were determined by the isotachophoresis method. The measurements were performed at pH = 4.2, 6.0 and 8.0. In each case the proper leading/terminating electrolyte system was selected on the basis of literature and authors'own research. The results of isotachophoretic analyses were found to be in good agreement with the results derived from dissociation constants determined by potentiometric method. Considerable difficulties were encountered in interpretation of the results obtained for pH = 8.0 since individual steps in the isotachopherograms were fuzzy and distorted probably due to incomplete separation of the analysed sample into zones. Knowledge of the kind and concentration of ligand forms of chelating compounds, to which PBTC and NTMP belong, can be useful for reclamation of soils polluted with heavy metals.