| 英文摘要 |
The study was carried out from August to November 2007 in the Tongshi Bay along Chiayi county to monitor some environmental factors for the oyster industry. The highest degree of the water temperature detected was 30.4℃ at September and the lowest 22.8℃ was at November. The lightest water of 23.5ppt was measured at September followed by 26.7ppt of August. The salinities were higher at cold months around 30.0ppt.The pH measured at each month were similar around 8.0. Both dissolved oxygen measured in the water of upper and bottom water were similar; they were around 5.00ppm at September and 8.4ppt at November. The concentration of sulfate in the bottom soil of the culture area (CA) was around 0.01500g/g and was about 20 times higher than that of the reference point (RP).
The concentrations of phosphorous, NH3-N, Nitrate and COD of CA were higher than those of RP at hot months. The situation reversed, most of those were higher in RP than in CA.
The concentration of Cu, Pb, Cd, As, Zn and Hg in the water of August was 10.25ppm, 2.19ppm, 2.66ppm, 2.74ppm, 44.12ppm and 7.34ppm respective. The concentration of Cu, Pb, Cd, As, Zn and Hg in the water of November wasThere were 10 species of diatom in the water of CA in September,the abundance was 3520cells/L. At the same time, there were 31 species of diatom in the water of RP, the abundance was 17160cells/L。There were 21 species of diatom in the water of CA in November, the abundance was 10032cells/L. At the same time, there were 13 species of diatom in the water of RP, the abundance was 7392cells/L。
There were 31 different groups of zooplankton in the water of CA in September, the abundance was 22322 ind’s/100m3; at the same time, there were 32 different groups of zooplankton in the water of RP, the abundance was 1062590 ind’s/100m3. There were 32 different groups of zooplankton in the water of CA in November, the abundance was 39825 ind’s/100m3; at the same time, there were 26 different groups of zooplankton in the water of RP, the abundance was 12264 ind’s/100m3.
There were 17 species of dwellers collected on the vertical-hanging strings of the floating racks locating at southern CA in September, the average number of individuals was 186.5 per string; and 19 species of dwellers collected in the northern CA with 151.2 individuals per string. At the same, there were 8 species of dwellers on the horizontal-hanging strings of fixed racks,each string had average number of 54.8. There were 19 species of dwellers collected on the vertical-hanging strings of the floating racks observed at southern CA in November, the average number of individuals was 308.0 per string; and 19 species of dwellers in the northern CA with 223.7 individuals per string. At the same, there were 12 species of dwellers on the horizontal-hanging strings of fixed racks,each string had average number of 120.7.
The oxygen consumption rate of cultured oysters both collected in September and November were lower with larger body size; these negative relationships were highly linearly correlative. At 28℃, oxygen consumption rates of the oysters collected in September were higher than those of the oysters collected in November. The slope of correlation linear measured in September was larger than that did in November.
The upper cultches of vertical-hanging strings contained more oysters than those of the lower ones, but the ratios of the shells with and without soft tissue on each cultch were similar for all. The body sizes of oysters on the upper cultches were larger than those on the lower ones; and the upper clutches had larger productions. |