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Sandu Bay 5 cage culture area from 2005 to 2007 to investigate the type of survey items including water reactive phosphate, inorganic nitrogen and the underlying sediments sulfide, organic carbon, benthic organisms, biomass, habitat density, group, access to water capacity of cage culture, cage culture History and cage culture Survey. According to the analysis of the survey results, screened closely associated with cage culture capacity factor, then, in accordance with the standards, the estimated amount of Sandu Bay cage culture capacity and investigation of sea cage can be raised. The main results are as follows: the 1.5 cage culture area of ??inorganic nitrogen content in the range of 0.413 ~ 0.754 mg / L, significantly higher Sandu Bay surveys the average content of inorganic nitrogen (0.347 mg / L); reactive phosphate content range of 0.036 ~ 0.082 mg / L, Sandu Bay reactive phosphate also higher than the average content (0.027 mg / L) surveys. Caused by of Sandu Bay local waters nitrogen, phosphorus content increased significantly Description cage culture, cage culture area of ??inorganic nitrogen and active phosphate content of all the more than two types of marine water quality standard, up to four types of marine water quality standards, exceeding more serious . Cage culture area water quality sampling day and night monitoring cage culture area waters near there high nitrogen and phosphorus content of the water masses, with the tidal fluctuation from the movement in the cage culture area; cage culture area of ??nitrogen, phosphorus with tidal change; trend played a large role in the cage culture area active phosphate and inorganic nitrogen transport; nitrogen and phosphorus content of extreme values ??(maximum and minimum) often appear to lag behind in the the Gaoping tide and low-lying tidal moment . Sediment sulfide content presents the distribution law of diminishing around since the cage center. Sulphide content of the central area (399 ~ 1 377 mg / kg) more than the first class marine sediment quality standard (300 mg / kg), and most of the marginal zone sediment sulfide content (30 ~ 439 mg / kg) compliant control zone (500 m) from the cage edge sulfide content (22 ~ 246 mg / kg) all in compliance with the standard. 3. Organic carbon content also showed the distribution law of diminishing around since the cage center, the central area of ??the organic carbon content of 1.01 to 1.27%, an average of 1.13%; marginal zone of 0.94 to 1.34%, an average of 1.07%; The control area of ??0.90 to 1.25%, with an average of 1.06%, the cage culture all stations did not exceed the organic carbon content of marine sediment quality standards (2.0%). The cage culture center area density of benthic habitat, biomass minimum; marginal zone habitat is less dense, less biomass; minimum control zone habitat density, biomass largest. Minimum cage the central area of ??the diversity index, dominance; minimum control area's diversity index, dominance; diversity index of the edge of the area and the dominance ranking above both the middle. The survey results show that each cage patches of water quality and sediment has been the impact of cage culture, cage culture center area most severely affected, the edge of the area by mild impact to the environment, the control area (from cage culture area edge 500 m) and is less affected, The sediment environment quality in line with marine sediment quality standards. Through investigation and statistical analysis, we found the sediment sulfide content and stocking density has a good correlation, sediment sulfide content and stocking density equation. Using the equation Sandu Bay cages the cage culture capacity can be raised on the waters, the results show that the of Sandu Bay cages fitness-fed waters of cage aquaculture capacity of 1.26 kg / m ~~; estimates, Sandu Bay 5 The appropriate amount of containing the fish cage culture area (the highest annual production limits) were: three are Island Area 14,400 t, 06,700 t of white-based Bay Area, Dongan Island Area, 06,400 t, long waist Island Area 15,900 t, 47,500 t Qingshan Area.
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