Abstract:

Total nitrogen is an important index of water. Excessive total nitrogen can cause eutrophication of rivers, lakes and reservoirs, Marine red tide, groundwater pollution, and even harm human body. The main sources of total nitrogen are the application of excessive nitrogen-containing fertilizer in agricultural planting, the irregular accumulation and discharge of feces and urine in livestock and poultry breeding, the misconnection and mixed connection of urban domestic sewage pipes, and the direct discharge of rural domestic sewage into rivers caused by non-treatment. The total nitrogen in the environment generally has the characteristics of “accumulation in sunny days and release in rainy days”. Various nitrogen-containing pollutants are stored in the ground soil and branches and canals, and washed into rivers or leached into groundwater with rainfall, causing water pollution. Total nitrogen is diverse in form and easy to transform, and ultimately exists in the form of nitrate nitrogen with strong solubility and stability, so it must be controlled from the source. The fundamental way to reduce total nitrogen pollution in water is to control source and intercept pollution combined with long-term management. Combined with relevant standards and norms, technical guidelines, literature review and practical experience, this paper conducted a comprehensive and systematic analysis from the aspects of the existence form and transformation of water total nitrogen, source analysis and source control measures, aiming to enhance the importance of source control, so as to provide a reference for scientific and effective reduction of river total nitrogen.

Key words: total nitrogen, agricultural planting source, livestock and poultry breeding source, urban domestic source, rural domestic source, source control