One might ask, aren’t plant nutrients supposed to have benefits? Why is it harmful to water? In this chapter, water quality online monitoring instrument manufacturers come to understand the harm brought by plant nutrients to water bodies with you!
Plant nutrients mainly contain nitrogen, phosphorus and other substances that stimulate the production of algae and aquatic grasses, interfere with water purification, and thus make BOD5 rise. However, too many nutrients in the water body will cause “eutrophication”, and the harm caused to lakes and slow-moving water bodies has become an important issue of water source protection.
So what is eutrophication? It means that under the influence of human activities, nutrients needed by organisms enter the water body, resulting in the rapid reproduction of algae and other floating objects, the decline of dissolved oxygen in the water body, and the deterioration of the water quality, resulting in a large number of fish and other organisms. The process of eutrophication brought by nature is very slow, but man is not the same, and the eutrophication caused by artificial discharge of industrial wastewater and domestic sewage containing nutrients is formed in a short time.
The sources of plant nutrients are wide and large, including domestic sewage (organic matter, detergent), agriculture (fertilizer, farm fertilizer), industrial wastewater, garbage, etc. The content of phosphorus and nitrogen (especially phosphorus) in natural water bodies is to some extent a controlling factor for plankton growth. When a large amount of nitrogen and phosphorus plant nutrients are discharged into the water, some organisms (such as algae) are rapidly multiplied and grown, and the growth cycle becomes shorter. After the death of algae and other plankton, they are decomposed by aerobic organisms, constantly consuming dissolved oxygen in the water, or are decomposed by anaerobic microorganisms, constantly producing gases such as hydrogen sulfide, which deteriorates the water quality, causing a large number of fish and other aquatic organisms to die. Algae and other plankton residues in the process of decay, and the biological needs of nitrogen, phosphorus and other nutrients released into the water, for the new generation of algae and other organisms to use. Therefore, after eutrophication, even if the source of external nutrients is cut off, it is difficult to self-purify and return to normal levels. When the water body eutrophication is serious, the lake can be silted up by some numerous plants and their remains, and become a swamp or even dry land. Some areas of the sea can become a “Dead Sea”, or a “red tide” phenomenon.
Commonly used nitrogen and phosphorus content, before controlling nutrients in water, it is necessary to understand the specific content of the nutrient, usually the content of nitrogen and phosphorus, productivity (O2) and chlorophyll-α as indicators of the degree of eutrophication of water. To prevent eutrophication, the content of nitrogen and phosphorus entering water must be controlled. As for monitoring the content of nitrogen and phosphorus in water, TN-8000 total nitrogen online analyzer and TP-8000 total Phosphorus online analyzer produced by Hangzhou Modi can respectively monitor the content of these two data.
