| Environmental stress is an important inducement which could bring on the massmortality and the decline of the quality of sea food. Only one stressor is hardly toinduce the mass mortality, but the bivalves would die when many stressors operatetogether. It's necessary to research on effects of environmental stress onEcophysiological characteristics of bivalves, as which helps to find out themechanism of mass mortality, and helps to construct a sustainable and stable culturemodel. In this paper, some preliminary researches of effects of environmental stress onecophysiological characteristics of bivalves have been done in situ. In addition, adetection method of catecholamine in the hemolymph of the bivalves is established. The main results are as follows: 1. The effects of environmental stress on clearance rates of suspension-feedingbivalves have been studied in situ. The results show that stressors have an significanteffect on clearance rates of Chlamys farreri. The minimum clearance rate(1.60L/ind·h ) appears in August which has the highest temperature all the year. Thisminimum value is obviously lower than the average which is 9.51L/ind·h. The mainstressors are high temperature and pathogen. 2. The effects of environmental stress on biodeposition rates ofsuspension-feeding bivalves have been studied in situ. The results show that stressorshave an significant effect on biodeposition rates of Chlamy farreri in August. Theminimum biodeposition rate (0.44g/ind·d) appears in August, which is obviously lowthan the average 2.72g/ind·d. The main stressors are high temperature, food depletion,reproduction stress and environmental pollution et al.. 3. The effects of environmental stresses on oxygen consumption rates ofsuspension-feeding bivalves have been studied in situ. Chlamy farreri andCrassostrea gigas have similar rules. Their oxygen consumption rates reach to themaximum (2.63mg/g·h and 2.13mg/g·h, respectively) in July, 2002. The oxygenconsumption rates display the minimum value (0.39mg/g·h and 0.07mg/g·h,respectively) in January, 2002 when the water temperature reaches to the lowest. Thenthe oxygen consumption rates increase, and come to the highest again (2.13mg/g·hand 2.10mg/g·h, respectively) in July, 2003. The average temperature in July is lowerthan August 2.5 ℃. In August when the temperature comes to a head, the oxygenconsumption rates of Chlamy farreri and Crassostrea gigas both decrease. The mainstressors are high temperature, reproduction stress and food depletion et al.. 4. The effects of environmental stresses on ammonium excretion rates and O: Nratio of suspension-feeding bivalves have been studied in situ. The ammoniumexcretion rates of Chlamy farreri vary from 1.45-6.64μmol/ind·h, and the average is2.92μmol/ind·h. The minimum is in January, and the maximum is in August. The O: Nratios are less than 20 in August and September. It reaches to the least (16.26) inAugust, and then come to a head 124.1 in November. The O: N ratios of Crassostreagigas are less than 20, and the maximum is in July. The results show increasedreliance on protein as a catabolic substrate rather than carbohydrate and lipid inAugust. The lowest O: N ratios in January reflect that the bivalves have to meet theirenergy demand by metabolizing more protein to survive. The low O: N ratios alsoreflect the metablic adjustments to the demand of nutrients necessary to sustaingametogenesis. The main stressors come from temperature, reproduction stress andfood depletion. 5. Chlamys farreri and Crassostrea gigas are selected as experimental animals.High-performance liquid chromatography with the electrochemical detector ispracticed sensitively. The collection of hemolymph should be finished within 1.5minutes. Glutathione is a proper antioxidant. When 1.5ml hemolymph, 25mg aluminaand 1ml Tris buffer are used, the recovery is higher than others. To prevent dilution,the alumina has to be centrifuged to dryness after the washing step. The recovery ratesof norepinephrine, epinephrine and dopamine are repectively 53~69%,...
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