Oxygen budget for an urban estuary

1982 ◽  
Vol 33 (4) ◽  
pp. 607
Author(s):  
DW Connell ◽  
HC Morton ◽  
BM Bycroft

Various processes affecting the dissolved oxygen content of waters of the Norman Creek estuary, Brisbane, were measured or estimated and standardized for the mid tide daylight situation. Over a 9-week period, accrual, aeration and photosynthetic processes resulted in the daily addition of 76,225 and 214 kg oxygen, respectively, and export, deaeration, biochemical oxygen demand, plant respiration and benthic respiration in the daily loss of 30, 89, 91, 97 and 335 kg oxygen, respectively. These processes are highly dynamic, with substantial daily turnover in the water mass. Benthic sediments; enriched with organic matter, exercise a major influence on the dissolved oxygen content of the water.

1997 ◽  
Vol 1997 (1) ◽  
pp. 989-990 ◽  
Author(s):  
Zhao Jianqiang ◽  
Zhu Junhuang

ABSTRACT Three major factors affecting the biodegradation of spilled oil (chemical composition of spilled oil, dissolved oxygen content in water, and nutrient elements for microorganisms) were analysed. The sequences of biodegradation rates of some hydrocarbon compounds are summarized. The oxygen demand for biodegradation of 1 g of hydrocarbons was derived as 3 to 4 g. The maximum ratio of carbon (C), nitrogen (N), and phosphorus (P) that microorganisms need was suggested as C:N:P = 100:7:0.14.


2015 ◽  
Vol 181 (2) ◽  
pp. 161-168
Author(s):  
Nadezhda K. Khristoforova ◽  
Alexander A. Emelyanov ◽  
Ksenia S. Berdasova ◽  
Yulia E. Degteva

Spatial distribution and seasonal variability of the basic ecological parameters for marine water, as dissolved oxygen content, biochemical oxygen demand, and permanganate oxidizability are considered for the Eastern Bosporus Strait (Peter the Great Bay, Japan Sea) on the data obtained in autumn, spring and summer seasons of 2013-2014, with special attention to the Ajax and Paris Bights of Russky Island on the southern coast of the Strait, changed significantly after construction of new university campus and marine aquarium. Normal oxygen regime is observed over the whole strait in autumn, but cases of low dissolved oxygen content, close to the minimal permissible level, are revealed in spring and summer. This phenomenon is an important feature of environmental conditions in the Strait in the warm period. It is possibly reasoned by general pollution of marine environments by sewage water, high water temperature, and relatively high concentration of suspended matter caused by active water circulation in the narrow strait and heavy rains. However, there is no any specific anthropogenic impact on the oxygen content in the Ajax and Paris Bights.


2010 ◽  
Vol 2010 ◽  
pp. 1-18 ◽  
Author(s):  
Yuan Tian ◽  
Kaibiao Sun ◽  
Andrzej Kasperski ◽  
Lansun Chen

The control of substrate concentration in the bioreactor medium should be due to the substrate inhibition phenomenon. Moreover, the oxygen demand in a bioreactor should be lower than the dissolved oxygen content. The biomass concentration is one of the most important factors which affect the oxygen demand. In order to maintain the dissolved oxygen content in an appropriate range, the biomass concentration should not exceed a critical level. Based on the design ideas, a mathematical model of a chemostat with Monod-type kinetics and impulsive state feedback control for microorganisms of any biomass yield is proposed in this paper. By the existence criteria of periodic solution of a general planar impulsive autonomous system, the conditions for the existence of period-1 solution of the system are obtained. The results simplify the choice of suitable operating conditions for continuous culture systems. It also points out that the system is not chaotic according to the analysis on the existence of period-2 solution. The results and numerical simulations show that the chemostat system with state impulsive control tends to a stable state or a period solution.


1954 ◽  
Vol 11 (6) ◽  
pp. 933-953 ◽  
Author(s):  
W. Percy Wickett

By using standpipes set 12 inches into the stream bottom the oxygen content and apparent velocity of the gravel water in the controlled-flow section of Nile Creek were observed. Values of dissolved oxygen content and velocity that just supply the full oxygen demand of salmon eggs were defined. The high mortalities of chum salmon eggs in the pre-eyed stage, that have been found in certain areas, may be explained on the basis that oxygen demands of 0.00013 to 0.0003 mg./egg/hr. at temperatures of 0.1° to 8.2 °C. were not being met, owing to very low oxygen content or very low apparent velocity of the water in the gravel. Values as low as 0.2 p.p.m. and 2 mm./hr. were recorded. A portable gravel-water sampler is described, which can be used (1) to obtain samples of subsurface water for the determination of dissolved oxygen; and (2) to calculate apparent velocity of gravel water from rate of dilution of an added dye.


1979 ◽  
Vol 14 (1) ◽  
pp. 71-88
Author(s):  
S.E. Penttinen ◽  
P.H. Bouthillier ◽  
S.E. Hrudey

Abstract Studies on the chronic low dissolved oxygen problems encountered under winter ice in the Red Deer River have generally been unable to account for dissolved oxygen depletion in terms of known manmade inputs. An experimental program was developed to assess the possible nature and approximate bounds of oxygen demand due to natural organic runoff carried to the Red Deer River by a small tributary stream, the Blindman River. The study employed an electrolytic respirometer on stream water samples subjected to prior concentration by vacuum evaporation. Evaluation of carbon and nitrogen budgets in conjunction with the measured oxygen demand indicate that biochemical oxygen demand is originating with natural organic runoff in tributaries of the Red Deer River. The results provide a basis for estimation of the possible contribution to the observed oxygen demand in the Red Deer River originating from natural organic runoff.


1998 ◽  
Vol 38 (10) ◽  
pp. 23-30
Author(s):  
Sarah Jubb ◽  
Philip Hulme ◽  
Ian Guymer ◽  
John Martin

This paper describes a preliminary investigation that identified factors important in the prediction of river water quality, especially regarding dissolved oxygen (DO) concentration. Intermittent discharges from combined sewer overflows (CSOs) within the sewerage, and overflows at water reclamation works (WRW) cause dynamic conditions with respect to both river hydraulics and water quality. The impact of such discharges has been investigated under both wet and dry weather flow conditions. Data collected from the River Maun, UK, has shown that an immediate, transient oxygen demand exists downstream of an outfall during storm conditions. The presence of a delayed oxygen demand has also been identified. With regard to modelling, initial investigations used a simplified channel and the Streeter-Phelps (1925) dissolved oxygen sag curve equation. Later, a model taking into account hydrodynamic, transport and dispersion processes was used. This suggested that processes other than water phase degradation of organic matter significantly affect the dissolved oxygen concentration downstream of the location of an intermittent discharge. It is proposed that the dynamic rate of reaeration and the sediment oxygen demand should be the focus of further investigation.


2021 ◽  
Vol 186 ◽  
pp. 106216
Author(s):  
Jiande Huang ◽  
Shuangyin Liu ◽  
Shahbaz Gul Hassan ◽  
Longqin Xu ◽  
Cifeng Huang

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