The introduction of dissolved oxygen in pond aerator
introduction of dissolved oxygen in pond aerator
first, dissolved oxygen
dissolved oxygen in the water is composed of oxygen, oxygen consumption this to contradictory decisions. Oligotrophic waters and flowing water into oxygen to the atmosphere, oxygen saturation, not more. Eutrophic oxygen from photosynthesis. In nature water of dissolved oxygen in the Aquarium's gross income, photosynthesis oxygen 89%, dissolved oxygen air about 7% and 4% for water supply oxygen. Water from biological respiration of oxygen consumption, decomposition of organic matter. In General, escaping into the air only about 1.5% total oxygen consumption, fish oxygen consumption only reckons also other result above all biological respiration, decomposition of organic matter consumption. Eutrophic water rich bio-, lots of organic matter, oxygen, oxygen the sharp contradiction movement; the dissolved oxygen concentration of water is very unstable, UPS and downs, changed a lot, especially in summer, it is worth attention. Changes of dissolved oxygen which law? ⑴ Diurnal variation of dissolved oxygen distribution, water dissolved oxygen maximum in the afternoon before sunset, the minimum value occurs in the morning before sunrise. B general law of vertical distribution of dissolved oxygen: ① day at noon and afternoon, much dissolved oxygen in surface water, saturation can be as high as 200%, little dissolved oxygen in the bottom water, saturation is about 40-80%, or even lower. In midwater, drastic reduction in dissolved oxygen increasing with depth, forming a "jump". General tendencies are: increased with depth, dissolved oxygen content decreased rapidly. II night, especially after midnight, declining dissolved oxygen concentration, vertical distribution tends to be uniform. C under the action of wind, the level of dissolved oxygen distribution uniformity, when there is a wind, the level of dissolved oxygen distribution is not uniform. Upwind low dissolved oxygen during the day, downwind oxygen high natural convection of water through the night, upwind early this morning dissolved oxygen high downwind of low dissolved oxygen.
Second, the effect of dissolved oxygen on aquatic animal
⑴ when oxygen is ≤ 2 mg/l, the water easy to aging, stink, floating heads, Allen died. Critical oxygen in pond fish in China between 1-2 mg/l. ⑵ When the dissolved oxygen content between 2-5 mg/l, aquatic animals can live normal, but growth was restrained, not productive. ⑶ When ≥ 5-7 mg/l dissolved oxygen, and normal life to ensuring the sustainability and related biota, reproduction, full growth. When the dissolved oxygen below the optimum range for a long time, decline in exercise capacity in aquatic animals, reduce feeding, feed coefficient, resistance, increased disease, breeding obstruction of biological acres (hectares): 1-5 (test)