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Abstract  

Marine invertebrates are well known to accumulate trace metals from seawater, plankton, sea plants, and sediments. To test the usefulness of such organisms as a bio-indicator of environmental conditions, we have determined levels of trace elements in tissue of twelve species of marine invertebrates by photon and neutron activation analysis. Relatively higher concentration of elements were observed for Ni and Sn in mid-gut gland, for Cu and Zn in oyster tissues, for Se in swimming crabs, for Cu, Fe, and Se in gills of swimming crabs. Our results indicate that mid-gut gland of ear-shell will be useful as the indicator of environmental conditions.

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Abstract  

The capacity of algae to concentrate uranium under natural environmental conditions is measured by a-spectrometry. Spirogyra, a filamentous green fresh-water alga, has concentrated uranium from a surface concrete ponds with elevated uranium levels (140-1140 ppb). The concentration factors (CFs) ranged from 8.9-67 with an average value of 22.Cladophora spp, a filamentous green marine alga has concentrated uranium from the marine water with a concentration factor ranged from 220–280. The average concentration factor was 250. The factors affecting the sorption process are discussed in detail.

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Abstract

The aim of the study is to determine the environmental conditions in the territory of the Myjava river basin (Slovakia) in order to analyze changes in the ecological stability from the first military mapping (1769–1784) until the present (2020). Except of the assessment of the ecological condition of the area, the stress factors of the territory were evaluated together with proposed measures according to the need to improve the current situation. The ecological prosperity of the landscape was evaluated based on the several methodologies used in Slovakia including coefficients of ecological stability. The results pointed to changes in ecological stability during the period evaluated, together with analyses of the stress factors that are currently affecting the territory researched.

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The osmotic stimulation which is able to change the behavioral state of the animal are most effective during rainy weather while they are less effective during dry weather conditions. In isolated CNS preparations from aestivated animals the highest firing activity and serotonin sensitivity of the serotonergic (RPas) heart modulator neurons are recorded during rainy weather and the lowest parameters are observed in dry conditions. In aestivated animals the serotonin (5HT) content in both the CNS and the foot is higher than the dopamine (DA) content during rainy weather, while in dry weather the DA level is higher than the 5HT. The inactivation-reactivation process is accompanied by decreasing both the DA and 5HT levels in the CNS and increasing them in the peripheral organs. Our results suggest that aestivated animals adapt to (favorable and unfavorable) environmental conditions by modulating their central arousal state through changing the levels and distribution of monoamines (5HT, DA) in their body.

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The spatial distribution of bivalves in relation to environmental conditions was studied along a second- and third order stream — medium-sized river (River Ipoly) — large river (River Danube) continuum in the Hungarian Danube River system. Quantitative samples were collected four times in 2007 and a total of 1662 specimens, belonging to 22 bivalve species were identified. Among these species, two are endangered (Pseudanodonta complanata, Unio crassus) and five are invasive (Dreissena polymorpha, D. rostriformis bugensis, Corbicula fluminea, C. fluminalis, Anodonta woodiana) in Hungary. The higher density presented by Pisidium subtruncatum, P. supinum, P. henslowanum and C. fluminea suggests that these species may have a key role in this ecosystem. Three different faunal groups were distinguished but no significant temporal change was detected. The lowest density and diversity with two species (P. casertanum and P. personatum) occurred in streams. The highest density and diversity was found in the River Ipoly, in the side arms of the Danube and in the main arm of the Danube with sand and silt substrate, being dominated by P. subtruncatum and P. henslowanum. Moderate density and species richness were observed in the main arm of the Danube with pebble and stone substrate, being dominated by C. fluminea and S. rivicola. Ten environmental variables were found to have significant influence on the distribution of bivalves, the strongest explanatory factors being substrate types, current velocity and sedimentological characteristics.

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Environmental conditions (soil, weather) have the greatest impact on the production of all crops, so it is necessary to check the behaviour of new hybrid combinations under diverse environmental conditions. In 2009 and 2010, field trials were sown at various locations in Croatia to test new sunflower hybrid combinations bred at the Agricultural Institute in Osijek. In both years, the trials were conducted in Beli Manastir (BM09 and BM10), Nova Gradiška (NG09 and NG10) and Osijek (Os09 and Os10), while in 2010, a trial was also sown in Vukovar (Vu10). The genotypes included three cytoplasmic male sterile lines (cms 1–3) as female parent with a set of 8 fertility restorer lines (four branching restorers: oG1–4 and four single-headed restorers: oM5–8). The grain yield data were processed for years and locations (7 environments) using analysis of variance (ANOVA) and Additive Main effects and Multiplicative Interactions (AMMI) analysis with the SAS for Windows 9.1 statistical software. To obtain a better picture of the grain yield stability of the hybrid combinations in different environments, AMMI1 and AMMI2 biplots were made using IRRISTAT for Windows 5.0 software. No significant differences were found between the hybrid combinations of the female lines (cms 1–3). Among the environments, the significantly highest grain yield was recorded in the environment Os09 (4.220 t ha−1), followed by BM09 and Os10. As regards the restorers the highest grain yields (statistically on par with each other) were found for hybrid combinations involving oG2 and oM7 (3.726 and 3.666 t ha−1). Together, the first two interaction principle components (IPC) explained 85.4, 76.6 and 64.8% of the variability for crosses involving cms1, cms2 and cms3, respectively. The AMMI1 and AMMI2 biplots showed that the highest yielding hybrid combinations did not have the most stable grain yield. The greatest stability was shown by restorer line oM7 in cross combinations with inbred lines cms1 and cms2, while the same restorer line exhibited a large genotype × environment interaction and low stability when crossed with cms3.

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Trifolium pratense cv. Minshan is a dominant red clover variety for animal feeding and pharmaceutical industry in Alpine Pasture Region of Gansu province, northwest China. In order to achieve the best isoflavone production, a 3-year trial was conducted at three locations to study variations of hay yield, total isoflavone concentration and isoflavone yield at different growth stages under different environmental conditions. Predominant isoflavone compounds and distribution of isoflavones in leaves, stems and inflorescences were also investigated. The results indicated that there were large variations on hay yield and isoflavone concentration among different sites, growth stages, age and parts of the plant. Minshan red clover harvested at the flower bud stage had the highest isoflavone yield (86.30 kg ha−1). The temperate climate region, Guanghe, provided the best growth conditions among three sites for isoflavone production (58.93 kg ha−1). The highest isoflavone production (53.42 kg ha−1) appeared at the second year of crop. In Minshan red clover, isoflavones are mainly distributed in leaves (1.12%). The predominant isoflavone compounds were formononetin (0.27%) and biochanin A (0.25%).

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. Distribution, abundance, and diversity of stream fishes under variable environmental conditions. Can. J. Fish. Aquat. Sci. 63: 43–54. Warren M. L. Distribution, abundance, and diversity

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Photosynthetic responses, the non-structural carbohydrate pool and its alterations, and the acid invertase activity under different environmental conditions in the fructan synthesising Porella platyphylla and Sphagnum flexuosum are discussed. Sucrose and fructan are the major soluble carbohydrates in both species. TLC showed that fructans form a homologous series of increasing DP in a similar manner to fructans in Angiosperms and belong to the inulin type. Exogenous sugars (glucose, fructose, sucrose) applied in light and dark resulted in down-regulation of photosynthetic activity, but a long period (1 week) of dark starvation did not cause a significant decrease in the photosynthetic capacity. Light and exogenous sugars increased soluble carbohydrate content due to fructan-accumulation. Dark starvation, desiccation and low temperature did not influence significantly the amount of the total soluble carbohydrates, indicating the existence of a well-buffered carbohydrate pool, although changes in the ratio of fructans of different molecular weight can be detected. Alterations in the activity of acid invertase correlated well with the changes of the amount of the main soluble carbohydrates, showing the role of the enzyme in general carbohydrate and fructan metabolism.

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Abstract  

In order to assess the extent of the elimination of humidity and the presence of pine trees on the elemental composition of airborne dust, the concentration of 21 elements were measured in airborne dust collected with a high-volume sampler at JAERI by instrumental neutron activation analysis (INAA). It was found that the concentration of soil-origin elements, such as Al, Sc and Th, decreased as the humidity increased, and the Cl/Na ratio of sea salt constituent in the dust samples increased with the decrease of humidity after the felling of the trees.

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