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1

Optimization of Seaweed Harvesting for Maximum Antimicrobial Activity – Impact of Seasonal Variation, Temperature, and Salinity

Farid Younes, Jaatit Loubna, Chennaoui Mohammed

Journal of Ecological Engineering

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2024

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Vol. 25, nr 2

244--249

EN

Algae are highly adaptable and can thrive in different environments, making them ideal for synthesizing effective and affordable antibacterial compounds. To optimize the harvesting of marine algae and determine the period during which the algae display maximum activity, the effect of seasonal variation (during a closed year) as well as temperature and salinity on the antimicrobial activity of fifteen species of algae (four species belonging to the Chlorophyceae class, two species belonging to the Phaeophyceae class and four species belonging to the Rhodophyceae class) was studied. These algae were tested for their antimicrobial activity against S. aureus, B. cereus, E. coli, and C. neoformens. These observations revealed that the optimal harvesting season for phaeophyceae and rhodophyceae extracts is spring, whereas that for chlorophyceae is during the summer period, when temperature and salinity are at their highest. In this study, it was found that the largest inhibition diameter of algae extracts occurs during summer.

2

Retrospective Analysis of Ukrainian Air Transport Activity

Bugayko Dmytro, Antonova Anna, Shevchenko Olga, Shevchuk Dmytro

Logistics and Transport

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2022

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Vol. 53-54, No. 1-2

79--97

EN

Ukraine is an aviation state that has a full cycle of development and serial production of aircraft, commercial operation of civil aviation, training and retraining of professionals for the industry. The level of development of air transport determines not only the country's image, but also the sustainable development of its national economy. The article presents a structural analysis of the trends in the development of world aviation transport, as well as the economic development of aviation transport in Ukraine and its infrastructure. The authors pay special attention to the study of the factors of the seasonality of air transportation and their influence on the results of the operational activities of air transport in Ukraine.

3

Use of Quality and Organic Pollution Indices in The Physico-Chemical Quality Assessment of Kébir Wadi East Surface Waters (Region of El Taref, Extreme North East Algeria)

Bahroun Sofia, Nouri Nada, Smida Bouthaina

Civil and Environmental Engineering Reports

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2022

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Vol. 32, no. 1

43--58

EN

Surface water is subject to strong anthropogenic pressures caused by the development and the extension of the agricultural activities and also by the industrial and domestic activities. Pollution is a major environmental problem due to discharges into rivers and the excessive use of agricultural fertilizers add to that the discharges from urban and industrial sources. The aim of this study is to assess the quality and the state of the organic pollution of surface water in the Kébir wadi east, based on the Water Quality Index (WQI) and the Organic Pollution Index (OPI) during six sampling campaigns carried out between April and September of the year 2011. Seven stations were studied along the Kébir wadi east downstream from the Mexa Dam. The results are visualized by the use of GIS through making thematic maps. They revealed that half of the stations show excellent to good water quality and moderated organic pollution except the stations S3, S6 and S4, that have poor water quality and high pollution at S3 and S6 respectively, and non-potable water with very high organic pollution at S4. The anthropogenic environmental deterioration recorded in the wadi is the result of the use of nitrogen and phosphate agricultural fertilizers and especially, the discharge of untreated domestic and industrial wastewater from neighbouring agglomerations. The seasonal variation remains discrete and reflects a slight tendency to the deterioration of the waters of El Tarf region during the low waters of the summer period.

4

Assessment of seasonal variation of the bioactive oleuropein in Olea europaea L. leaves cultivated in Saudi Arabia

Alqarni Mohammed Hamed, Salkini Mohamad Ayman, Alam Prawez, Alanazi Mazen Talal, Abdel-Kader Maged Saad, El Sohafy Samah M.

Acta Chromatographica

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2022

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Vol. 34, no. 3

297--303

EN

Plants secondary metabolites undergoes qualitative and quantitative variation due to environment al and growth factors. It is a crucial factor to select the proper time for collection of medicinal plants to assure maximum content of active components reflected as maximum efficacy. Olive leaves (Oleaeuropaea L.) are known traditionally for their antidiabetic effect. The secoiridoid glycoside oleur-opein is the main active component of Olive leaves responsible for the biological activity. The current study was conducted to monitor the seasonal variation of oleuropein in Olives leaves collected from the same location. To achieve this goal a validated HPLC method following the ICH guidelines was established. Separation was conducted using RP18 column and a mobile chase consisted of ultrapure water containing 20% acetonitrile and 1% acetic acid. Detection was performed at 254 nm with 1 mL/min flow rate. The method was simple, linear, accurate, precise, specific and robust. The analyses revealed considerable variations in the level of oleuropein throughout the year. This variation cannot be explained by temperature variation during the year. Two points of high levels of oleuropein were detected prior to flowering stage and ripening of the fruits. The levels of growth regulators most likely is responsible for the increased production of oleuropein. It is recommended that leaves intended for medicinal use to be collected during the fruiting stage prior to fruit ripening.

5

The Efficiency of Aquatic Macrophytes on the Nitrogen and Phosphorous Uptake from Pond Effluents in Different Seasons

Kalengo Lilian, Ge Hailong, Liu Nannan, Wang Zhijian

Journal of Ecological Engineering

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2021

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Vol. 22, nr 8

75--85

EN

The present study investigated the efficiency of four aquatic macrophytes: Lemna spp, Pistia stratiotes, Ipomoea aquatica and Eichhornia crassipes on nitrogen and phosphorous utilization from aquacultural effluents concerning seasonal changes and biomass production. These nutrients in excess affect fish health and cause eutrophication in water bodies, hence affecting the ecosystem. Aquatic macrophytes were planted in tanks filled with the effluents from carp pond and other tanks were left without plants, serving as control/algal treatment. The water samples were collected weekly for analysis of total nitrogen (TN), ammonia-nitrogen (NH3-N), nitrate-nitrogen (NO3-N), total phosphorus (TP) and ortho-phosphate (ortho-P). The results show that average water temperature raised from 12.2 ± 0.21 °C in winter to 32.0 ± 0.4 °C in summer with no significant difference (p>0.05) between treatments whereas pH was neutral in winter and slightly alkaline in the other seasons. Seasonal changes had impact on macrophytes biomass accumulation with the highest in spring for Lemna spp (91.3%), followed by P. stratiotes (81%) and in summer, E. crassipes (64%). Autumn and winter had the lowest biomass accumulation and I. aquatica had the lowest values in all seasons. For each season, the nutrients concentration decreased with no significant difference (p>0.05) between treatments. Average NH3-N removal efficiencies were higher during summer and autumn followed by spring and lowest in winter for all treatments. NO3-N and TN decreased significantly from the highest in summer to the lowest in winter in all treatments. The ortho-P removal efficiency was slightly higher than TP and decreased from the highest in spring to the lowest in winter (91.4% to 7.8%, control/algae; 90.3% to 8.4%, E. crassipes; 86.2% to 8.3%, Lemna spp; 82.5% to 10.8%, P. stratiotes). The chlorophyll a concentration was higher in Lemna spp (62.2 μg/L) and control/microalgae treatments (59.3 μg/L) indicating that there was probably microbial community that contributed to nutrient utilization. Aquatic macrophytes, in association with microalgae, were responsible for the nitrogen and phosphorous removal. Seasonal temperature change affects the growth and nutrients uptake of aquatic macrophytes. A decrease in temperature reduces the efficiency of nutrients removal and biomass production. For an effective N and P removal from pond effluents in a given season, selection of a proper aquatic macrophyte must be taken into consideration with regards to a given season.

6

An assessment of seasonal variations in the cref cors at the University of Lagos

Nwilo Peter Chigozie, Ayodele Emmanuel Gbenga, Okolie Chukwuma John, Orji Michael Joseph, Marve Mnguhenen Funmilayo, Oyelade Esther Abidemi, Daramola Olagoke Emmanuel

Geomatics, Landmanagement and Landscape

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2020

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no. 1

63--77

EN

Continuously Operating Reference Stations (CORS) are reference stations of the Global Navigation Satellite System (GNSS), providing fundamental positioning infrastructure that is accurate and reliable. As such, CORS are designed to meet the needs of a wide range of users requiring high three-dimensional (3D) positional accuracy. The Continuously Operating Reference Station at the Engineering Faculty (CREF), University of Lagos was set up in order to support research applications in Surveying, Mapping and Geodesy. This study evaluates the seasonal variations in the 3D coordinates of CREF using metrics such as coordinate differences, Standard Deviation (SD) and Standard Error (SE). The Canadian Spatial Reference System (CSRS), known as CSRS – Precise Point Positioning (CSRS-PPP) was used to compute the station’s daily coordinates over a three-year period from 2016 to 2018. In the analysis, the daily coordinates were divided into two seasons - the wet and the dry. The results obtained show that the dry and the wet seasons had SDs (5.4 mm, 3.9 mm, and 2.0 mm) and (5.2 mm, 18.6 mm and 14.4 mm) in the x, y and z-directions respectively. Generally, the dry season presents a better result than the wet season as revealed by the accuracy metrics. These results have led to an increased understanding of the seasonal variability inherent in the data acquired by GNSS CORS, and must be taken into consideration: in particular, for GNSS applications such as the weather prediction and water vapour estimation. This study concludes that more needs to be done regarding the maintenance of CREF to ensure data continuity and reliability for geodetic studies.

7

Lipid content and fatty acid composition of Mediterranean macro-algae as dynamic factors for biodiesel production

El-Maghraby D. M., Fakhry E. M.

Oceanologia

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2015

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No. 57 (1)

86--92

EN

Using the total lipid contents and fatty acid profiles, the marine macro-algae Jania rubens (Rhodophyceae), Ulva linza (Chlorophyceae) and Padina pavonica (Phaeophyceae) were evaluated for biodiesel production during the spring, summer and autumn. Seawater parameters such as pH, salinity and temperature were measured. The total lipid content varied from 1.56% (J. rubens) to 4.14% (U. linza) of dry weight, with the highest values occurring in spring. The fatty acid methyl ester profiles were analysed using gas chromatography. The highest percentage of total fatty acids was recorded in P. pavonica, with 6.2% in autumn, whereas the lowest was in J. rubens, with 68.6% in summer. The relative amount of saturated to unsaturated fatty acids was significantly higher in P. pavonica than in the other macro-algae. Seasonal variations in pH, salinity and temperature had no significant effect on the total lipid and fatty acid contents. Principal component analysis grouped brown and green algae together, whereas red alga grouped out. Furthermore, methyl ester profiles indicate that brown and green seaweeds are preferred, followed by red seaweeds, which appears to have little potential for oil-based products. Therefore, these seaweeds are not targets for biodiesel production.

8

Distribution and Seasonal Variation of Heavy Metals in Sediments of Muthupet Lagoon, Southeast Coast of India

Balakrishnan T., Sundaramanickam A., Shekhar S., Balasubramanian T.

Journal of Ecological Engineering

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2015

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Vol. 16, nr 3

49--60

EN

This study deals with seasonal variation of heavy metals in sediments of Muthupet lagoon, Southeast coast of India from September 2011 to August 2012. The bulk sediments were association with sand, silt and clay. Geoaccumulation index (lgeo) was used to quantitatively assess the influences of heavy metal pollution. Heavy metals were determined by using Inductively Coupled Plasma Optical Emission Spectrometer (ICP-OES) and the results were compared to permissible limits of WHO/USEPA. The minimum concentration of heavy metals in all the stations were found during the post monsoon and summer seasons and the maximum concentration of heavy metals in all the stations were found during the premonsoon and monsoon seasons. The reason for the pollution was land drainage, irrigation through channels and municipal wastes and also the peak agricultural activities due to the release of fresh water from reservoirs. Among all the metals iron was found to be maximum in all the stations in postmonsoon and summer season followed by magnesium and manganese. Apart from these three metal, all other six metals are recorded in moderate range. The reason for the high concentration of these metals are anthropogenic activity, agriculture, aquaculture and the rivers regular in and out flow throughout the study duration in the lagoon area.

9

The effects of litter layer and soil properties on the soil-atmosphere fluxes of greenhouse gases in karst forest, Southwest China

Cheng J., Lee X., Zhou Z., Wang B., Xing Y., Cheng H., Tang Y.

Polish Journal of Ecology

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2013

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Vol. 61, nr 1

79--92

EN

Temporal variation is a major source of the uncertainty in estimating the fluxes of the greenhouse gases (GHGs) in terrestrial ecosystems, and the GHG fluxes and its affecting factors in the karst region of southwest China remains weakly understood. Using the static chamber technique and gas chromatography method, the CO2, CH4 and N2O fluxes were carried out between 9 and 11 a.m. at 15 day intervals from June 2008 to May 2009 in a Pinus massoniana forest. Two treatments were chosen for this study: undisturbed (soil with litter layer) and disturbed (surface litter removal). Both treatments were found to be the net source of atmospheric CO2 and N2O, but a sink of atmospheric CH4. The seasonality of soil CO2 emission coincided with the seasonal climate pattern, with high CO2 emission rates in the hot-wet season and low rates in the cool-dry season. In contrast, seasonal patterns of CH4 and N2O fluxes were not clear, although higher CH4 uptake rates were often observed in autumn and higher N2O emission rates were often observed in spring (dry-wet season transition). The litter was active in GHG fluxes, and removal of the litter layer reduced soil CO2 emission (17%) and increased CH4 uptake (24%) whereas N2O fluxes were not affected distinctly in the pine forest, indicating that litter layer had an important effect on C exchanges. In the pine forest, soil CO2 emissions and CH4 uptakes correlated significantly with soil temperature (r2 = 0.87, P <0.01; r2 = 0.34, P <0.05, respectively), but had no significant relationship with soil moisture. And there was a significant correlation between CH4 flux and NH4+-N (r2 = 0.39, P < 0.05) and soil inorganic N (r2 = 0.48, P <0.05), but no significant correlation was found between CH4 flux and NO3--N. Moreover, we found a significant negative logarithmic correlation between N2O flux and soil NO3--N concentration (r2 = 0.41, P <0.05), and the relationship between CO2 emission and soil inorganic N content (r2 = 0.35, P < 0.05). These results suggested that soil temperature and mineral N dynamics largely affected the temporal GHG exchanges between forest soil and atmosphere.

10

Health Risk Factors in Different Seasons of Carpet Industry in Kashmir, India

Wani K. A., Jaiswal Y. K.

International Journal of Occupational Safety and Ergonomics

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2012

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Vol. 18, No. 4

571--577

EN

Carpet workers are exposed to different types of health risk factors in different seasons of the year. As the environmental conditions become harsh, risk for developing various types of diseases increases. These problems are further aggravated when the environmental conditions at the workplace deteriorate. An attempt has been made to study the health risk factors in the carpet industry in different seasons of the year. It has been concluded that in winter weavers are affected by several types of health risk factors as compared to the other seasons.

11

Seasonal and diurnal variation of outdoor radon (222Rn) concentrations in urban and rural area with reference to meteorological conditions

Podstawczyńska A., Kozak K., Pawlak W., Mazur J.

Nukleonika

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2010

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Vol. 55, No. 4

543-547

EN

The objective of the study was to investigate temporal variability of outdoor radon (222Rn) concentration registered in the center of Łódź (urban station), at Ciosny (rural station) and Kraków (suburban station) in relation to meteorological parameters (i.e. air temperature, temperature vertical gradient, wind speed, soil heat flux, volumetric water content in soil) with special consideration of urban-rural differences. Continuous measurements of 222Rn concentration (at 60 min intervals) were performed at a height of 2 m above the ground using AlphaGUARDŽ PQ2000PRO (ionization chamber) from January 2008 to May 2009. 222Rn levels were characterized by a diurnal cycle with an early morning maximum and a minimum in the afternoon. The well-marked 24 h pattern of radon concentration occurred in summer at anticyclonic weather with cloudless sky, light wind and large diurnal temperature ranges. The urban measurement site was characterized by the lowest atmospheric 222Rn concentration and an urban-rural differences of radon levels increased from winter to summer and during the nighttime periods. The maximum contrasts of 222Rn levels between Łódź and Ciosny, reaching – 30 Bqźm–3, were registered in June and July during the urban heat island (UHI) phenomenon (a positive thermal anomaly of a city if compared to rural area) and strong thermal inversion near the ground in the rural area.

12

Fitoplankton w ocenie trofii Zbiornika Koronowskiego

Wiśniewska M., Puszkiewicz K., Ziółkowski K.

Ekologia i Technika

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2010

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R. 18, nr 1

21-31

PL

Przeprowadzona w 2008 r. w Zbiorniku Koronowskim w obszarze jeziora Lipkusz analiza fyko-logiczna wykazała 91 taksonów glonów planktonowych (Cyanoprokaryota - 30, Pyrrophyta - 2, Euglenophyta - l, Chrysophyceae - 3, Bacilla-riophyceace - 21, Chlorophyta - 34). Biomasa w okresie wiosennym była tworzona głównie przez okrzemki, natomiast w okresie letnim - przez okrzemki i sinice. Na podstawie składu gatunkowego, biomasy fitoplanktonu, koncentracji chlorofilu-a i TSI zaliczono wody Zbiornika Koronowskiego ogólnie do typu eutroficznego z intensywną ekspansją sinic uznawanych za potencjalnie toksyczne.

EN

Algae analysis that was carried out in Koronowski Reservoir in 2008 shows 91 phytoplankton species (Cyanoprokaryota- 30, Pyrrophyta- 2, Euglenophyta- l, Chrysophyceae- 3, Bacillariophyceace- 21, Chlorophyta - 34). Biomass during the spring season was composed mainly by diatoms, but in the summer season by cyanobacteria and diatoms. In the strength of algae species composition, biomass, chlorophyll-a concentration and a Trophic State Index (TSI) - Koronowski Reservoir was generally classified as a eutrophic.

13

A comparative seasonal pollution assessment study on Ennore Estuary with respect to metal accumulation in the grey mullet, Mugil cephalus

Padmini E., Vijaya Geetha B.

Oceanological and Hydrobiological Studies

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2007

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Vol. 36, No.4

91-103

EN

Environmental pollution is currently a major concern due to unorganised and increased industrialization and urban development. In the Tamilnadu state of India, on the Bay of Bengal, lies the Ennore estuary, which is an important industrial centre. The main industries in the region include a fertilizer company, refineries, a rubber factory, paint industry and a thermal power station. Investigations into the seasonal pollution impacts on the distribution of various metals in the waters of the Ennore estuary, situated in North Chennai, Tamilnadu, India, and the concentrations of some of the toxic metals in the tissue of the grey mullet, Mugil cephalus L., inhabiting in the same estuary were conducted during the period of April 2004 to March 2006. The results were compared to those of the Kovalam estuary, which is unpolluted. In the water at one sample site of the Ennore estuary, heavy metal concentrations ranged between: Pb 0.15-0.23, Hg 0.05-0.06, Cd 0.01-0.03, and Cr 3.33-1.093 ppm for summer and monsoon seasons, and were significantly related to the seasonal rains (p<0.01). In contrast, heavy metal concentrations in the Kovalam estuary ranged between: Pb 0.043-0.039, Hg non-detectable-0.001, Cd 0.01-0.098, and Cr 0.063-0.052 ppm, and were not significantly related to the rainy season. The metal concentrations found in the muscle tissues of Mugil cephalus L., at the same site on the Ennore estuary were: Fe 11.06 š0.29, Zn 1.67 š0.14, Cr 2.98 š0.15, and Pb 1.26 š0.11 ppm, which were also significantly related to season (p<0.01). The metal concentrations in fish inhabiting the Kovalam estuary were: Fe 2.17 š0.15, Zn 0.42 š0.05, Cr 0.63 š0.04, and Pb 0.31 š0.04, and showed no significant seasonal difference. The highest metal concentrations found in the tissues of the Ennore estuary fish which lead to the oxidative stress and shorten the lifespan of the fish are postulated to primarily result from anthropogenic activities and effluent discharge from the local industrial activities.

14

Speciation of heavy metals in the municipal sewage sludge

Siedlecka E., Bojanowska I.

Chemia i Inżynieria Ekologiczna

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2004

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Vol. 11, nr 10

1105--1110

EN

A sequential extraction Tessier method was used to determine the wastewater sludge fraction of Zn, Cu, Cd, Pb. The sludge was colleeted from the municipal wastewater treatment plant in Gdańsk region for , one year. Generally, the studied heavy metals were found in less soluble forms and in consequence only a part of its total content in sludge can be released to the soil and can become bioavailable. In 'exehangeable' and 'bound to carbonates' forms only Cu and Zn were found. Cd was found mainly as a 'bound to Fe-Mn oxides' forms. Pb and Zn were found as a 'bound to Fe-Mn oxides' forms, 'bound to organic matter' forms and 'residual'. Their distribution changed with seasons which was explained by coagulation process used for biological phosphorus removal in winter.

PL

Zestawiono wyniki badań zawartości wybranych metali ciężkich (Zn, Cu, Pb oraz Cd) we frakcjach wyodrębnionych w osadach ściekowych metodą ekstrakcji sekwencyjnej wg Tessiera. Próbki były pobierane przez rok z jednej z miejskich oczyszczalni ścieków na terenie Trójmiasta. Z przeprowadzonych badań wynika, że metale ciężkie w większości występowały we frakcjach silnie związanych z fazą stałą osadu czynnego, tak więc tylko część z nich mogła być uwalniana do roztworu glebowego i pobierana przez rośliny. We frakcjach "wymiennej" i "węglanowej" znaleziono Zn i Cu. Cd występował głównie we frakcji "tIenków żelaza i manganu". Pb i Zn związany były z "tIenkami żelaza i manganu", "materią organiczną" oraz "pozostałością". Zawartość metali ciężkich w poszczególnych frakcjach zależała od pory roku. Fakt ten związany był ze wspomaganiem biologicznego usuwania fosforu koagulacją sołami żelaza w okresie zimowym.

15

Cyanophyta blooms in Koronowski Reservoir in the background of environmental conditions

Wiśniewska M.

Oceanological Studies

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1998

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Vol. 27, No. 1

45-52

EN

On the basis of floristic analysis, the occurrence of 132 taxons of plankton algae in Koronowski Reservoir was determined. The spring and autumn plankton was dominated by diatoms, while summer plankton by blue-green algae. The species composition, structure of the abundance of algae and concentration of chlorophyll as well as physicochemical conditions of water suggested a highly eutrophic character of this reservoir with a starting expansion of blue-green algae, mainly species considered to be toxic.