Volume 4 Issue 5
Authors: Khaled S. AlQdah
Abstract: This investigation analysed the traffic noise pollution in the city of Amman in the Hashemite kingdom of Jordan. Twenty-two major locations, which are important streets and intersections in Amman connecting Amman with the south, the north and the airport of Jordan, were monitored. Monitoring of these selected locations has been conducted for three months. An equivalent A-weighted sound pressure level (LAeq) index was used, and the effect of workday and weekend traffic was conducted. The recorded results indicate that traffic noise levels are exceeding the accepted limits, which is 60 dBA for the day-time, at most of the locations. The reported results of the investigation showed that the minimum and the maximum noise levels are 51 dBA and 75.7 dBA during daytime. The Sweileh roundabout and the Alsena’ah traffic lights were found to be subjected to maximum noise levels of 75.7 and 72.63 dBA, respectively, because these sites are subjected to heavy traffic from the south. This study confirms the urgent need to establish a centre in Jordan for noise pollution monitoring and to develop local traffic noise standards. It is noted that people who live near the most polluted places suffer from some behavioural disorders and poor work performance.
Keywords: Noise Pollution; Traffic; Environment; Assessment; Survey
Authors: Lina Claudia Giraldo; Carlos Alberto Palacio; Nestor Jaime Aguirre
Abstract: This work aims to determine the enzymatic extracellular activity for the transformation of high molecular weight complex organic compounds and their temporal variation at the Aburrá-Medellín river “Aula Ambiental“ monitoring station. In order to evaluate the enzymatic activity of β-glucosidase and alkaline phosphatase in relation to the metabolism of carbon and phosphorus, in the water column and the biofilm attached to the rocky substrate of the river bed, seven monitoring campaigns were held between December 2010 and November 2011 at this site. By using a spectrophotometer, two specific substrates, namely 4-Nitrofenil-β-D-Glucopiranosa and 4-Nitrofenilfosfato were evaluated and analysed. From this evaluation, no significant differences were found among the monitoring campaigns, despite climatic variations presented during the study period, which may be due to the constant availability of nutrients in the river and to the continuous discharges of wastewater into the river. This research is a pioneering study in the region, which helps the understanding of the dynamics related to the microbial metabolism of nutrients in water bodies.
Keywords: β-Glucosidase; Alkaline Phosphatase; Enzymatic Activity; Aburrá-Medellín River