AERATION , IRRIGATION & DRAINAGE
The Benefits of Diffused Aeration Systems
iffused aeration
D systems are a great way to keep your pond , lake , fishery or reservoir in the best condition . So , what exactly causes low dissolved oxygen levels ?
Large amounts of algae and aquatic plants are the main culprits , as they absorb a great deal of oxygen after nightfall . High silt levels will also decrease dissolved oxygen levels in a lake or pond , releasing harmful gasses into the water . Finally having too many fish / wildfowl in your pond or lake can reduce your oxygen levels due to not only the oxygen consumption but also the increase in waste materials produced .
In a natural , ecologically balanced lake there would be little requirement for aeration . The added pressures exerted upon many lakes and reservoirs , during spring and summer especially , means added aeration is an essential management tool for most reservoirs , lakes , and ponds .
A water body with a healthy ecological balance is heavily dependent on oxygen . This includes fish stocks , microscopic bacteria essential for the processing of organic waste , the oxidisation of silt , the processing of harmful gasses or nutrients and several other processes .
PREVENTING THERMAL STRATIFICATION
Diffused air aeration systems are installed to prevent thermal stratification . During warmer periods water bodies will tend to suffer from thermal stratification , which occurs when the water in your pond , lake or reservoir becomes separated into layers . The top layer will contain oxygen-rich , warmer water whilst the bottom layer is comprised of cooler , oxygen-deficient water . These two
With technology constantly evolving the solar powered aeration systems available on today ’ s market are now more effective than ever . layers are separated by a layer known as a thermocline . The reason the top and bottom layers do not mix is because of the differences in density within the thermocline .
HOW DO DIFFUSED AERATION SYSTEMS WORK IN A POND OR LAKE ?
Diffused aeration systems work by pumping air through the membranes in the form of millions of tiny bubbles . As these bubbles travel to the water surface through the layers of thermal stratification they carry ( entrain ) cooler , oxygen-deficient water from the bottom layer up to the surface . The water then becomes naturally oxygenated as it reaches the surface .
From the circulation and aerating of the lower levels , toxic gases that would normally be trapped in the lower layer can be released . A balanced habitat for aquatic life is then maintained . This process creates healthy aerobic conditions at the lower levels of the pond or lake . This is where microbial processes can naturally break down nutrients that
Diagram showing thermal stratification
18 GroundskeepingJournal . co . uk | July 2022