Volume 3 Issue 10
Authors: Bla? Pipan; Mihael J. Toman
Abstract: The considerable data processing power available to everyday user has stimulated investigations into how mathematical modelling of predicted PPP concentrations can be used in environment protection. A small region in the north-eastern part of Slovenia was selected as a test site. According to used crops in that region, two PPPs were selected (Verita for vine and Poncho for corn). The selection of crops also influenced the selection of two representative locations (Tešanovci and Jeruzalem). Two important questions arose while running the simulations. The first one is not connected with the selection of above locations and PPPs. There is very little probability that all FOCUS scenarios belong to the same statistical population. The second question deals with a problem that is more tightly connected with environment protection. The method of calculation accepted in the FOCUS document has a serious drawback - 80% values of predicted concentrations. Daily concentrations in leachate are an order of magnitude higher! In locations of shallow and poor groundwater margin the permissible concentrations of active substances will be exceeded!
Keywords: Environment Protection; Matematical Modelling; Model PELMO; Plant Protection Products; Standard Scenarios
Authors: Inger Kühn; Jorge Hernandez; Bj?rn Olsen; Ann-Sofi Rehnstam-Holm; Stina-Mina Ehn B?rjesson
Abstract: In this study, twelve Mallards living in an artificial wastewater wetland were exposed to treated wastewater containing 1 x 103- 4 x 103 enterococci 100 ml-1 for a period of 55 days. Faecal samples were collected before, during and after exposure and analysed for Enterococcus spp. The isolates were phenotyped using the PhenePlateTM system. 270 Enterococcus spp. of Mallard origin were analysed, together with 116 Enterococcus spp. isolates from treated wastewater and from incoming raw wastewater. In general, the Mallard and wastewater enterococci isolates belonged to different phenotypes, although several sharing identical phenotypic profiles were found. One E. faecalis phenotype was found in Mallards before, during and after exposure to treated wastewater, as well as in raw and treated wastewater. Our results indicate that there is a common source of enterococci for Mallards and humans. We propose an increased focus on emissions of human bacteria and on systems that mediate their transfer to wild animals.
Keywords: Enterococcus Faecalis; Enterococcus Faecium; Anas Platyrhynchos; Mallard; Urban Wastewater; Sewage; Wastewater Wetland
Authors: Nain Elvira-Antonio; Alejandro Ruíz-Marí; Yunuen Canedo-López
Abstract: New alternatives for the production of fuels have led to considering the use of microalgae to obtain biofuel. Studies have reported that Chlorella vulgaris (59%), Nannochloropsissp (68%) and Neochlorisoleoabundans (54%) had high content of lipid under nitrogen limitation. The present study evaluated the effects on growth and lipid content of Chlorella vulgaris and Neochlorisoleoabundans under reduced nitrogen content and enrichment with sodium carbonate (Na2CO3). Both C. vulgaris and N. oleoabundans were cultivated in medium with NH4Cl and KNO3 as only source of nitrogen, respectively. The nitrogen initial content was of 30 mg l-1 at 32°C and light intensity of 100 μmol m-2 s-1.The maximum cell density obtained was of 21.80 x 106 cells ml-1 and 28.12 x 106 cells ml-1 for both microalgae, where higher growth rate was obtained for N. oleoabundans of 0.219 d-1 that C. vulgaris of 0.183 d-1 with similar lipids content (65.20-69.31%). In culture with Na2CO3 at concentrations of 1, 2.5 and 5 g l-1, the highest lipid content (69.5%) for C. vulgaris in culture with Na2CO3 of 1 g l-1 was obtained during 144 h of culture, whereas that for N. oleoabundans the 57.7% lipid content was obtained at 120 h. The lipid content and growth for both microalgae decreases at higher concentration of Na2CO3; caused probable by inhibition processes. The consumption rate of carbon dioxide showed that N. oleoabundans had a greater capacity and tolerance for using carbon dioxide and carbonate (112.8-115.2 mg l-1 d-1) with respect to C. vulgaris 95.76-105.75 mg l-1 d-1.
Keywords: Chlorella vulgaris; Neochloris oleoabundans; Nitrogen; Lipid Content; CO2 Consumption Rate