Influence of Insolation on the Efficiency of NO<Subscript>3</Subscript> Removal from Wastewater Treated in the Hydroponic System

The use of plants and natural processes for wastewater treatment is an issue that arouses interest among technologists and scientists around the world. The aim of the article was to analyze the influence of the air temperature and insolation on the removal of nitrate nitrogen from the wastewater treated in the hydroponic system, under greenhouse conditions. Samples of sewage for its quality tests were taken from a wastewater treatment plant (WWTP) located in the southwestern part of Poland. Data regarding daily sunshine duration and average daily air temperature values in selected periods of 2013–2016 come from a meteorological station located 30 km from WWTP. The conducted research and analyses of the results clearly indicate that under moderate climate conditions, the amount of solar radiation reaching the Earth’s surface is insufficient to ensure the year-round, effective wastewater treatment process in the hydroponic system. In the case of air temperature, no correlation was found between the tested parameters, which indicates the lack of temperature influence on the efficiency of NO₃ removal from the wastewater by macrophytes growing in the lagoon.     

Determination of elements removal in different harvesting scenarios of Scots pine (Pinus sylvestris L.) stands

Increasing demand for renewable energy and limiting CO₂ emissions have stimulated much interest in wood-based biofuels. Unfortunately, expanding the utilization of forest biomass may cause nutrient depletion in forested environments. This study investigates the element content from various parts of the tree. Comparisons were made between different harvesting scenarios and their impact on the amount of nutrients removed from the forest environment. The harvesting scenarios were: stem-only harvesting (SOH), branch and stem harvesting (BSH), and two variants of whole-tree harvesting (WTH). The elements taken into account were: carbon (C), nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sodium (Na), sulphur (S), copper (Cu), iron (Fe), nickel (Ni), manganese (Mn), zinc (Zn), cadmium (Cd), chromium (Cr) and lead (Pb). To make the results comparable, the same amount of removed biomass was taken into calculation. The differences between harvesting scenarios were significant. The amounts of removed elements formed similar pattern: the lowest level was found in SOH, average in BSH, and highest in both variants of WTH. This confirms that the application of WTH is connected with increased risk of nutrient depletion, even when the volume of harvest would be equal to other variants.     

Characteristics of permafrost-affected soil in a cliff in the central part of the Polish Baltic coastal zone

Purpose

The study aimed to characterise a fossil permafrost-affected (Stagnic Fluvisol Relictiturbic) soil, occurring in a cliff in the central part of the Polish Baltic coastal zone near Orzechowo (54° 35.664′ N, 16° 54.123′ E).

Materials and methods

The soil was sampled at 22 points and analysed using standard procedures in soil science. After standard preparation, disturbed and undisturbed soil samples were made subject to laboratory analyses concerning their physical and chemical properties. Radiocarbon dates and pollen analysis results were also obtained for the selected soil samples.

Results and discussion

The permafrost-affected soil lies beneath a fossil Dystric Histic Stagnosol, which is covered by about 8 m of aeolian deposits. The radiocarbon age of the Dystric Histic Stagnosol was 3061 ± 60 cal. years BP, and that of the Stagnic Fluvisol Relictiturbic 10,161 ± 110 cal. years BP. However, the results of pollen analysis suggest rejuvenation of the obtained dates. The Stagnic Fluvisol Relictiturbic developed in the marginal part of a body of water, from fluvioglacial and aeolian sands deposited on grey glacial till. The mineral substrates of the soil are moderately and poorly sorted sands and silt loam in the bottom part of the profile. This fine-textured material has been moved to the upper parts of the profile due to the impact of the water freezing and thawing cycles in the permafrost active layer. The observed microstructures on quartz grain (0.5–1.0 mm) surfaces, including conchoidal fractures, breakage blocks and v-shaped pits, are typical for periglacial soils. The fossil Stagnic Fluvisol Relictiturbic is poor in total iron. The observed vertical distribution of free iron oxides suggests their displacement in the permafrost active layer. Soil organic matter was found to be moderately or strongly humified, which is not typical for permafrost-affected soils and can suggest its allochthonous, probably alluvial, character.

Conclusions

The studied Stagnic Fluvisol Relictiturbic developed at the close of the Pleistocene in the marginal part of a body of water. It constitutes a sequence of horizons of varied thickness and abundance in organic matter. The influence of a periglacial environment is reflected in morphology of the soil (cryoturbations) and some chemical properties and partially in microstructures observed on quartz grain surfaces.

     

Determination of some phenolic acids in Majorana hortensis by capillary electrophoresis with online electrokinetic preconcentration

An online accumulation/mobilization preconcentration technique based on a dynamic pH junction technique and electrokinetic injection was employed for analysis of phenolic acids (sinapic, ferulic, coumarinic, caffeic, syringic, vanillic, and 4-hydroxybenzoic acid) in extracts from Majorana hortensis leaves. Samples were extracted by pressurized solvent extraction with acetone at 150 degrees C and 15 MPa. The capillary electrophoretic method employed 50 mmol.L (-1) sodium borate, pH 9.5, as the sample electrolyte, 50 mmol.L (-1) sodium phosphate, pH 2.5, as the background electrolyte, and 50 mmol.L (-1) sodium phosphate, pH 2.5, with 60 mmol.L (-1) sodium dodecyl sulfate as the mobilization electrolyte. The method allowed 720-fold to 5560-fold preconcentration of the phenolic acids during 30 min of electrokinetic accumulation with detection limits from 0.38 to 4.22 ng.mL (-1).     

Mineralization of the Bacillus thuringiensis Cry1Ac endotoxin in soil

Although a number of studies have been done describing the fate of Bacillus thuringiensis insecticidal endotoxins in soil, there is conflicting information on the persistence of this class of insecticidal toxins. This is partly due to methodological limitations in many of the previous studies. In the experiments reported here, 14C-labeled B. thuringiensis Cry1Ac endotoxin was used to study its mineralization in soil incubated under controlled conditions. Fifty-nine percent of the radiolabeled Cry1Ac was recovered as 14CO2 at the end of the 20 day incubation period. The addition of 4.5% corn residues stimulated mineralization of [14C]Cry1Ac toxin, and mineralization of glucose was 3.6 times faster than that of the Cry1Ac toxin, indicating that the soil was microbiologically and metabolically active. Because only low mineralization (approximately 6%) of the radiolabeled toxin was observed in autoclaved soil, the current findings indicate that microbial processes play a major role in the dissipation of the Cry1Ac endotoxin in soil. The results of this study suggest that there may be limited risk of the bioaccumulation of Cry1Ac in soil due to the eventual release of this insecticidal toxin by Bt-protected crops.     

Population structure,distribution and habitat use of the Critically Endangered Angelshark,Squatina squatina,in the Canary Islands

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The immediate effects of ditching a saltmarsh on nesting herring gulls Larus argentatus

We examined the effects of water management for mosquito control on the behaviour and breeding success of a resident colony of herring gulls. The colony resided on three close islands, one of which was ditched in March before the start of the second breeding season. The number of breeding pairs on the ditched island remained the same before and after ditching although the breeding number increased by 46% and 90% on the other two islands. Breeding chronology was similar on all three areas. However, birds nesting on spoil laid eggs a mean of 8 days later than non-spoil nesting birds. Behavioural observations on aggression and display rates indicated that birds on spoil behaved similarly to those in open grassy areas but differed from those nesting in the bushes. Nest site selection, breeding densities, and breeding success were similar on all three islands. Thus the differences noted were attributed to the appearance of the marsh. We postulated that pairs having nested on the experimental island in the previous year continued to do so after the island was ditched. However, pairs searching for new territory did not move onto the island that was ditched, but instead colonised the nearby islands. Similarly, those pairs breeding on spoil nested later because of the need to defend their nest sites which were situated in areas used for displaying by unmated birds.     

A retrospective multi‐center study of treatment,outcome, and prognostic factors in 34 dogs with disseminated aspergillosis in Australia

BackgroundDisseminated aspergillosis (DA) in dogs has a guarded prognosis and there is a lack of a gold standard treatment protocol.ObjectiveTo retrospectively assess survival times and factors influencing survival times.AnimalsDogs diagnosed with DA from January 2007 to June 2017.MethodsDisseminated aspergillosis case data were retrieved from 13 Australian veterinary referral centers, with a diagnosis confirmed with culture or PCR. Factors influencing survival time after diagnosis were quantified using a Cox proportional hazards regression model.ResultsThirty‐four dogs met the study inclusion criteria. Twenty‐two dogs were treated with antifungal treatment and 12 dogs received no antifungal treatment. Accounting for censoring of dogs that were either still alive on the date of data collection or were loss to follow‐up, dogs treated with itraconazole alone (n = 8) had a median survival time (MST) of 63 (95% CI: 20−272) days compared to 830 (95% CI: 267‐1259) days for the n = 14 dogs that received multimodal antifungal therapy (χ2 test statistic 8.6; df = 1; P < .01). The daily hazard of death (DHOD) for dogs with abnormally high serum creatinine concentration at the time of diagnosis was 7.4 (95% CI: 1.9‐29) times that of dogs with serum creatinine within the reference interval.Conclusion and Clinical ImportanceSerum creatinine concentration at the time of diagnosis is a useful prognostic indicator for survival after a diagnosis of DA. The MST for dogs treated with multimodal antifungal therapy is longer than itraconazole alone and warrant further investigation (P < .01).     

Validation of environmental DNA (eDNA) as a detection tool for at‐risk freshwater pearly mussel species (Bivalvia: Unionidae)

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The effect of cutting carnations in the bud stage on quality and yield of flowers from a nursery

The harvesting of carnation buds at early stages of development resulted in an increase of 10–60% (depending upon the growing-period and the cultivar) in the number of newly formed flower buds, even when the carnations were grown during a period of 11 months. A 22-month period of cultivation resulted in a larger increase in the number of buds.Tight buds could be successfully opened with opening-solution to fully developed flowers, without losing their quality when compared with control flowers harvested at the half-bloom stage.