Paulo Pereira

Atmospheric BTEX concentrations in the vicinity of the crude oil refinery of the Baltic region

Among chemical industries, petroleum refineries have been identified as large emitters of a wide variety of pollutants. Benzene, toluene, ethylbenzene, and xylene (BTEX) form an important group of aromatic volatile organic compounds (VOCs) because of their role in the troposphere chemistry and the risk posed to human health. A very large crude oil refinery of the Baltic States (200,000xa0bbl/day) is situated in the northern, rural part of Lithuania, 10xa0km from the town of Mažeikiai (Lithuania). The objectives of this study were: (1) to determine of atmospheric levels of BTEX in the region rural and urban parts at the vicinity of the crude oil refinery; and (2) to investigate the effect of meteorological parameters (wind speed, wind direction, temperature, pressure, humidity) on the concentrations measured. The averaged concentration of benzene varied from 2.12xa0ppbv in the rural areas to 2.75xa0ppbv in the urban areas where the traffic was determined to be a dominant source of BTEX emissions. Our study showed that concentration of benzene, as strictly regulated air pollutant by EU Directive 2008/50/EC, did not exceed the limit of 5xa0ppbv in the region in the vicinity of the crude oil refinery during the investigated period. No significant change in air quality in the vicinity of the oil refinery was discovered, however, an impact of the industry on the background air quality was detected. The T/B ratio (0.50–0.81) that was much lower than 2.0, identified other sources of pollution than traffic.

Anthropogenic effects on heavy metals and macronutrients accumulation in soil and wood of Pinus sylvestris L.

Abstract The investigation is focused on the uptake of heavy metals and macronutrients fluxes in Pinus sylvestris L. wood and soil under the sampled trees from contaminated and control sites. Soil pH, total organic carbon (TOC) and total and bioavailable heavy metals lead (Pb), cadmium (Cd), copper (Cu) and zinc (Zn) and macronutrients, potassium (K) and magnesium (Mg) were compared on contaminated and control sites. Also, metal uptake of contaminated and control pine woods was determined. Concentrations of soil bioavailable Cd (0.009 mg kg−1), Pb (0.11 mg kg−1), Cu (0.076 mg kg−1), Zn (0.51 mg kg−1) and K (24.42 mg kg−1), Mg (8.44 mg kg−1) on the contaminated plot were significantly higher (p < 0.001) than on the control plot 0.00004 mg kg−1 for Cd, 0.007 mg kg−1 for Pb, 0.002 mg kg−1 for Cu, 0.22 mg kg−1 for Zn and 7.81 mg kg−1 for K, 2.40 mg kg−1 for Mg. In addition, the percentage of bioavailable metals in contaminated soils was higher. Pb (34.49 mg kg−1), Cu (0.258 mg kg−1), Zn (1.36 mg kg−1) and K, ...

The shrubland as soil and water conservation agent in mediterranean-type ecosystems : The Sierra Enguera study contribution

John Thornes found that shrubland was a key factor in the control of soil erosion on Mediterranean hillsides. His research inspired many scientists to investigate the impact of shrubland changes and management in semi-arid ecosystems. An example of Professor Thornes’ scientific influence is the experiment carried out on the El Teularet–Sierra de Enguera experimental station since 2003 which showed erosion rates on a 30-year-old abandoned orchard with dense vegetation cover of Ulex parviflorus and Cistus albidus and a 20-year-old fire-affected maquia with Quercus coccifera, Pistacia lentiscus and Juniperus oxycedrus. The measurements demonstrated that the shrubs help create more stable soil temperature and to lower soil moisture content, whilst soil properties under the shrub cover showed a higher organic matter content, lower bulk density and higher soil water repellency. The two plots created have subplots of 1, 2, 4 and 16 m2, in which soil and water losses were measured. Those plots produced negligible runoff and sediment transportation during the very wet year of 2004 (715 mm rainfall). Rainfall simulation experiments at 55 mm h−1 during 1 h showed that even under 10-year return period thunderstorms, the patchy distribution of the shrubs is a key factor in controlling soil and water losses as they reduce the connectivity of the surface wash. These measurements confirm John Thornes’ idea that shrubland is an effective vegetation cover to control soil and water losses in Mediterranean ecosystems.

Anthropogenic effects on heavy metals and macronutrients accumulation in soil and wood of Pinus sylvestris L. / Antropogeninio poveikio įtaka sunkiųjų metalų ir makroelementų kaupimuisi dirvožemyje ir pušies (Pinus sylvestris L.) medienoje /

Abstract The investigation is focused on the uptake of heavy metals and macronutrients fluxes in Pinus sylvestris L. wood and soil under the sampled trees from contaminated and control sites. Soil pH, total organic carbon (TOC) and total and bioavailable heavy metals lead (Pb), cadmium (Cd), copper (Cu) and zinc (Zn) and macronutrients, potassium (K) and magnesium (Mg) were compared on contaminated and control sites. Also, metal uptake of contaminated and control pine woods was determined. Concentrations of soil bioavailable Cd (0.009 mg kg−1), Pb (0.11 mg kg−1), Cu (0.076 mg kg−1), Zn (0.51 mg kg−1) and K (24.42 mg kg−1), Mg (8.44 mg kg−1) on the contaminated plot were significantly higher (p < 0.001) than on the control plot 0.00004 mg kg−1 for Cd, 0.007 mg kg−1 for Pb, 0.002 mg kg−1 for Cu, 0.22 mg kg−1 for Zn and 7.81 mg kg−1 for K, 2.40 mg kg−1 for Mg. In addition, the percentage of bioavailable metals in contaminated soils was higher. Pb (34.49 mg kg−1), Cu (0.258 mg kg−1), Zn (1.36 mg kg−1) and K, ...

ANTHROPOGENIC EFFECTS ON HEAVY METALS AND MACRONUTRIENTS ACCUMULATION IN SOIL AND WOOD OF PINUS SYLVESTRIS L. / ANTROPOGENINIO POVEIKIO ĮTAKA SUNKIŲJŲ METALŲ IR MAKROELEMENTŲ KAUPIMUISI DIRVOŽEMYJE IR PUŠIES (PINUS SYLVESTRIS L.) MEDIENOJE / ВЛИЯНИЕ АНТРОПОГЕННОГО ЗАГРЯЗНЕНИЯ ТЯЖЕЛЫМИ МЕТАЛЛАМИ И МАКРОЭЛЕМЕНТАМИНА ПОЧВУ И СОСНУ ОБЫКНОВЕННУЮ (PINUS SYLVESTRIS L.)

Abstract The investigation is focused on the uptake of heavy metals and macronutrients fluxes in Pinus sylvestris L. wood and soil under the sampled trees from contaminated and control sites. Soil pH, total organic carbon (TOC) and total and bioavailable heavy metals lead (Pb), cadmium (Cd), copper (Cu) and zinc (Zn) and macronutrients, potassium (K) and magnesium (Mg) were compared on contaminated and control sites. Also, metal uptake of contaminated and control pine woods was determined. Concentrations of soil bioavailable Cd (0.009 mg kg−1), Pb (0.11 mg kg−1), Cu (0.076 mg kg−1), Zn (0.51 mg kg−1) and K (24.42 mg kg−1), Mg (8.44 mg kg−1) on the contaminated plot were significantly higher (p < 0.001) than on the control plot 0.00004 mg kg−1 for Cd, 0.007 mg kg−1 for Pb, 0.002 mg kg−1 for Cu, 0.22 mg kg−1 for Zn and 7.81 mg kg−1 for K, 2.40 mg kg−1 for Mg. In addition, the percentage of bioavailable metals in contaminated soils was higher. Pb (34.49 mg kg−1), Cu (0.258 mg kg−1), Zn (1.36 mg kg−1) and K, ...