Physical and Chemical Conditions of Bayur Bay Waters On the East and West Season

Physical construction of Bayur bay coastal area as a port was followed by a variety of environmental issues, both physical degradation of the natural environment, biology reduction and an increase in social problems, directly affect to water quality decreasing in the coastal Bayur Bay. This study aims to determine the concentration distribution of physical and chemical parameters and their influence to water conditions on the east and west season. The method used is descriptive method (data taken by in situ and laboratory analysis), determining the location of sampling points based on purposive sampling method and tide prediction by NAOtide software. The results of field survey and laboratory measurements analysed using statistical method. The speed of sea currents on the east season ranged from 3,48 to 24,9 cm.s-1, while in the West season flow rate ranged from 1,4 to 57,7 cm.s-1. Rainfall in East Season ranged from 0-45 mm and The intensity of rainfall in West Season ranged from 0-30 mm. Sea-surface temperatures in the Eastern season range between 26,2- 31.5 °C, while in the west season SST range from 24,3 to 30,5°C. Dissolve oxygen concentration in the east season range from 4,3 to 6,1 mg.L-1, while the west monsoon conditions range from 4,1 to 6,4 mg.L-1. The pH values ranged from 7,4 to 8,1 in the Eastern season and ranged from 7,12 to 8,27 in the West season. Bayur Bay water quality conditions is not much different from its value range on the west and east season and influencing each other. Keywords: Bayur Bay, Seasons, SST, Statistical method

Hydrodynamics of Bontang Seawaters: Its Effects on the Distribution of Water Quality Parameters

Bontang is a crowded with residential and industrial activities which produce heat waste into surrounding waters. This condition may cause environmental problems, and changes in water condition. Knowledge about dynamics of physic and chemical waters condition in Bontang city is very important as an effort to address environmental issues as part of coastal zone management and protection. The aim of this research is to understand hydrodynamic characteristics (tide and current) and the influence to distribution of physics and chemical in Bontang waters base on primary data (current and tide during one month, physics and chemicals waters data taken by in situ) and secondary data (bathymetry and tide forecasting). Hydrodynamic simulation is based on MIKE 21 and supported by CD-Oceanography and WR plot. The results show that the current is dominant move toward the Southwest and Northeast with current speed ranged from 0-0,22 m.s-1. The results of hydrodynamic simulation in the surface water show that the current move base on tide movement with current speed ranged from 0-0,24 m.s-1. The results of physic and chemical concentration is analysed by ArcGIS 10 to know spatial distribution of all parameters. Surface temperature ranged from 29-31,8oC, surface density ranged from 20-20,6 ppm, salinity ranged from 33,1-33,5 ppm, dissolve oxygen concentration ranged from 0,078-0,11 ppm. Distribution of all physic and chemical parameters is influenced by current and tide movement. Keywords: current, numerical model, water quality, Bontang waters

The Rybinsk Reservoir Water Quality: the Dissolved Oxygen Regime.

This study was undertaken to investigate the dissolved oxygen content and saturation percentage in surface and near-bottom water of the Rybinsk Reservoir in 2011-2015 with Winkler method. Seasonal and annual variations of the oxygen concentrations in the water body were identified. It was found that in summer time shallower water in the Main part was seldom subjected to oxygen stratification and if stratification occurred it ass less expressed than in deeper parts of the reservoir. Comparison of the new data on the dissolve oxygen concentration with the previously obtained data was made. Over the past years, there have not been any significant changes in the reservoir oxygen regime. The dissolved oxygen concentration in the reservoir seldom reached full saturation of the studied period. On average, aquatic organisms in the water body have enough dissolved oxygen. However, sometimes its concentration in nearbottom layers drops to critically low levels, threatening aquatic life.

Comparisons of Packing Materials in On-Site Wastewater Treatment System

Numerous biological, physical and chemical parameters are involved in retention and removal of chemical pollutant and bacteria in wastewater treatment systems. Biofilm presence was often cited for its influence in these mechanisms. Sandy soil is the most used packing material in wastewater treatment study and little information is available for the other soil. The objectives of this study were to compare purification efficiency of packing materials (soil) and to allow a better understanding in purification mechanisms in one-site wastewater treatment. Our work focused on water pollution removal and biofilm development. For this purpose, four experimental reactors were packed with sand and silt suitable for on-site wastewater treatment plant. They were dosed with septic effluent at loads of 5 and 12 cm/j for sand and 2 and 5 cm/j for silt. The purification performances and biofilm development were monitored on 245 for sand filters and 65 days for silt filters. Dissolve oxygen concentration from the treated effluents showed better values for the low loads and for the silt reactors. Also, organic pollutant remove by oxidation (COD and DOC) were better eliminated in the following reactors: Silt (2 cm/j) > Silt (5 cm/j) > Sand (5 cm/j) > Sand (12 cm/j). Adsorption was the mechanism of ammonium removal in silt although nitrification took part in sand. Biofilm development was observed in the first 2.5 cm and 10 cm in the sand reactors loaded at 5 and 12 cm/j respectively.