TOC, TP, TN and pH in sediment environment of shrimp culture and quality assessment module

In order to explore the relationship between environment quality and virus disease, in winter of 1995, the concentration of total organic carbon (TOC), total nitrogen (TN), total phosphorus (TP) and pH in bottom sediments of 80 shrimp culture ponds in Qingdao of China were determined, and the correlation between TOC, TP, TN and pH and pond age was analyzed. The results showed that TOC , TN were positive linear correlation with pond age, the correlation coefficient (γ) for TOC was 0.742 2-0.833 0 (P0.05), the correlation coefficient (γ) for TN was 0.460 3-0.857 4 (P0.05); TP was negative linear correlation with pond age in Liuting areas of Chengyang with correlation coefficient (γ) of 0.4261 (P0.05), and was positive linear correlation in other area with correlation coefficient (γ) of 0.495 6-0.906 0(P0.05). The relationship between pH and pond age was not regular. We suggested that the concentration of TN as an index of pond soil quality. A assessment module was established for environmental quality of shrimp pond bottom.