Decrease In Environmental Quality Research Articles

Use of the BMWP and ASPT indexes for monitoring environmental quality in a neotropical stream

The aim of the present study was to examine the applicability of versions of the Biological Monitoring Working Party index, the original from Great Britain (Armitage et al., 1983), and adaptations from Spain (Alba-Tercedor and Sanchez-Ortega, 1988) and Brazil (Junqueira and Campos, 1998; Junqueira et al., 2000; Monteiro et al., 2008), and the associated Average Score Per Taxon, in evaluating the environmental quality of a stream in the center-west of Brazil. In the wet and dry seasons, the stream was sampled at three sites, reflecting a gradient of increasing levels of anthropogenic impact from sites 1 to 3, and the different index values calculated. The adaptations by Junqueira et al. (2000) and Monteiro et al. (2008) presented the highest values. The values of the versions of Junqueira and Campos (1998) and Junqueira et al. (2000) generally decreased from sites 1 to 3 on both dates. Decreases in environmental quality on the wet season sampling date were indicated by the BMWP scores more so than by the ASPT scores. The adaptations by Junqueira and Campos (1998) and especially Junqueira et al. (2000) seem to have detected, with the greatest degree of sensitivity, the putative decrease in environmental quality from sites 1 to 3. The use of the ASPT seemed to diminish the possible impact of natural seasonal differences in organism abundances on the indicated degree of pollution.

The response of primary producer assemblages to mitigation measures to reduce eutrophication in a temperate estuary

The Mondego estuary is a well-described system located on the North Atlantic Ocean, where cultural eutrophication progressed over the last decades of the 20th century. Consequently, and due to a large productivity of Ulva spp., Zostera noltii meadows were severely reduced with a concomitant decrease in environmental quality. In 1998, experimental mitigation measures were implemented, via changes in hydrology to increase circulation and diversion of nutrient-rich freshwater inflow, to reverse the process in the most affected area of the estuary – its South arm. The objective of this study was to assess the differences in response of primary producer assemblages to the implemented measures to reduce eutrophication. Results show that the mean concentrations of DIN suffered a notorious decrease due to a significant reduction in the ammonium concentration in the water column, while DIP increased significantly. Primary producer assemblages showed different responses to these changes: phytoplankton, measured as concentration of chlorophyll a, did not show any significant changes; green macroalgae, mostly Ulva spp., suffered a large reduction in biomass, whereas Gracilaria gracilis and the macrophyte Zostera noltii biomasses increased greatly. Results show that phytoplankton biomass has remained constant and suggest that the reduction in ammonium could have been responsible for the changes in the green macroalgal biomass. Light was the most likely factor in the response of seagrass whereas red macroalgal reaction seemed to be dependent on both light and ammonium.

An Analogy on Assessment of Urban Air Pollution in Turkey Over the Turn of the Millennium (1992–2001)

Rapid industrialization and urbanization in Turkey, especially over the last twenty five years, has provided better living standards to its residents, but it also caused a decrease in environmental quality. In late 1970's, air quality monitoring activities were started in some major cities by individual researchers in Turkey. It was just around the 1990's that a countrywide program on continuous air pollution monitoring in major province centers and selected large towns was launched. The impact of air pollution on people depend on various factors, such as existence and magnitude of coal powered energy generation plants, type of urban heating and their efficiency, and the numbers and specifications of vehicles. In this study, current Turkish urban air quality over the turn of the Millennium (1992-2001) is studied in the light of the country's worst cities in terms of outdoor air quality, the number of upper respiratory diseases, sinusitis, bronchitis, and pneumonia cases in these provinces reported by the state medical treatment facilities in 2001. The population that is under outdoor urban air pollution hazard was computed. A comparative analysis between the provinces that use natural gas and others that use fossil fuels was also completed in order to project monetary gains if the studied provinces will transform their indoor heating and industrial operations to be run by natural gas or other cleaner energy sources. If natural gas use in air polluted urban centers could be realized in the near future, approximately 212 to 350 million US dollars per annum could to be saved just by reducing health related problems caused by outdoor air pollution.