Dissolved Oxygen Meter - Nature of Dissolved Oxygen Changes in Pond Culture
Nature of changes in dissolved oxygen in pond culture
There are four important changes in dissolved oxygen: horizontal, vertical, diurnal and seasonal changes. Among them, diurnal, vertical and horizontal changes have a greater impact on pond fish.
1. Diurnal changes: During the day, when the temperature is low at dawn, the photosynthesis of phytoplankton that moves to the upper water as the intense light moves to the upper water is enhanced after the sun comes out. The carbon dioxide produced by biological respiration at night is absorbed and consumed, and the dissolved oxygen in the upper water continues to increase and the pH rises. High, reaching the peak at 3 to 4 o'clock in the afternoon. At this time, due to the existence of thermocline water body, it is not easy to convection, and the dissolved oxygen in the lower water drops to a low level. After that, photosynthesis weakens, dissolved oxygen slowly decreases, and carbon dioxide slowly increases. Before sunrise (5 to 6 o'clock), dissolved oxygen drops to a low level, while carbon dioxide reaches a maximum value, and the pH drops to a low level.
2. Vertical changes: Due to the influence of light intensity, the dissolved oxygen in deep water ponds also has certain changes in the vertical direction. Generally, when the light intensity of the upper water of the pond is greater during the day, the photosynthesis of phytoplankton is stronger and the dissolved oxygen is higher; The light intensity of the water in the lower layer is weakened, and due to thermal resistance, the water in the upper and lower layers is not easy to convection, and the dissolved oxygen is low. Especially in summer afternoons, the temperature difference between the upper and lower water layers is large, the water body is stable, and the dissolved oxygen in the bottom water is almost zero.
3. Horizontal changes: Under the influence of different wind directions and wind forces, there are more plankton and organic matter in the water body downwind than upwind. In other words, the amount of dissolved oxygen produced by phytoplankton downwind on a sunny day and the amount of oxygen dissolved from the air are greater than those upwind. The stronger the wind, the greater the difference in dissolved oxygen content upwind and downwind. The horizontal distribution of dissolved oxygen at night is just opposite to that during the day. The dissolved oxygen in the upwind position is greater than that in the downwind position. This is because there are more plankton and organic matter in the downwind position, so the oxygen consumption is also greater. The difference in dissolved oxygen upwind and downwind is also related to wind power, pond aspect ratio, plankton mass, and the amount of organic matter.
The most indispensable thing in the field of aquaculture is water quality sensors, and water quality sensors are subdivided into: pH sensors, dissolved oxygen sensors, chlorine dioxide sensors, free chlorine sensors, turbidity sensors, water quality conductivity sensors, etc., all of which are It is a high-precision product used in aquaculture, environmental pollution, water pollution, industrial wastewater pollution and other fields.
Dissolved oxygen is a member of the water quality sensor family, and is also a sensor mostly used in the aquaculture industry. Dissolved oxygen sensors can be divided into: underwater electrical dissolved oxygen sensors, Yuasa dissolved oxygen sensors, and fluorescence dissolved oxygen sensors based on their functions and characteristics. Sensors, optical oxygen sensors, etc. are the best tools for protecting the aquaculture industry.
Nature of changes in dissolved oxygen in pond culture
Aquaculture has relatively strict requirements for the pond water environment, emphasizing the rationality of the dissolved oxygen content of the pond water. The horizontal, vertical, diurnal changes and control measures of dissolved oxygen in pond water were analyzed. On this basis, the changing rules and control strategies of oxygen surplus and oxygen debt were expounded from the aspects of seasonal changes and daily changes, aiming to strengthen the control measures. Understanding changes in dissolved oxygen in aquaculture ponds, thereby promoting the continuous development of aquaculture technology.
