Jingsheng Chen, Tao Yu, Ongley Edwin
College of Environmental Sciences, Peking University, Beijing, 100871, PR China.
Environ Monit Assess. 2006 May;116(1-3):321-34. doi: 10.1007/s10661-006-7374-2.
Using the Yellow River, China, the study explores the problem of the use of COD and BOD(5) as water quality management parameters in the presence of very high levels of suspended sediment (TSS) that characterize this river. Although the amount of natural organic matter per unit of suspended sediment of the Yellow River is not high, the very high concentration of mineral sediment in the Yellow River results in a large concentration of organic matter, which artificially inflates the laboratory values of COD and, as a consequent, leads to greatly exaggerated reports of pollution of the Yellow River. BOD(5) can more accurately reflect the pollution of the Yellow River than COD; however, measured values of BOD under-report the actual values due to settling of the sediment in the incubation chamber resulting in values that are 21.6--38.3% less than the actual values. Therefore corrections are required for laboratory COD and BOD values so that the values are not artifacts of the sediment regime. Our work provides new insight into this phenomenon and demonstrates how correction factors may be determined and used with pollution data. Our work also suggests that the actual pollution levels of the Yellow River are probably not as high as reported by monitoring agencies.
该研究以中国的黄河为对象，探讨了在黄河这种具有高悬浮泥沙（总悬浮物，TSS）特征的河流中，将化学需氧量（COD）和生化需氧量（BOD₅）用作水质管理参数所存在的问题。尽管黄河单位悬浮泥沙中的天然有机物含量不高，但黄河中极高的矿物泥沙浓度导致了大量有机物的存在，这人为地抬高了COD的实验室测定值，进而导致对黄河污染情况的报告被大幅夸大。与COD相比，BOD₅能更准确地反映黄河的污染情况；然而，由于泥沙在培养箱中沉降，BOD的测量值低于实际值，测量值比实际值低21.6% - 38.3%。因此，需要对实验室测定的COD和BOD值进行校正，以使这些值不会因泥沙状况而产生偏差。我们的研究为这一现象提供了新的见解，并展示了如何确定校正因子以及如何将其应用于污染数据。我们的研究还表明，黄河的实际污染水平可能不像监测机构报告的那么高。
