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根据2007年12月和2008年6月三门湾海域的2个航次的渔业资源调查资料,研究三门湾海域口足目与十足目中虾类在冬季和夏季的密度、优势种及多样性的时空分布,并结合该调查海区的地形地貌和水文等因素对虾类的分布进行分析。结果表明,三门湾海域虾类以广温、广盐种为主,其夏季种类数高于冬季,且夏季虾类质量和尾数密度均值亦高于冬季,夏季与冬季的虾类质量分别为93.32 kg/km2和31.97 kg/km2,而尾数密度分别为32.34×103 ind/km2和19.32×103 ind/km2。依据相对重要性指数IRI的计算,得出该海域冬季最主要的优势种为细巧仿对虾(Parapenaeopsis tenella),夏季为口虾蛄(Oratosquilla oratoria)。夏季虾类种间分配较为均匀,致使该海域冬季虾类质量及尾数多样性指数值H’均值(1.58,1.33)皆低于夏季质量和尾数H’均值(1.78,2.18)。在冬季,三门湾口外海域水温较高,导致较多数量虾类出现。在夏季,湾口水域有不同盐度水团混合交汇,也使此处虾类的种类和数量较多。依据本文调查资料,三门湾海域十足目虾类种类数占浙江近海游泳虾类的25.00%,其种类丰富度要小于浙江近海。
Based on the survey data of fishery resources of two voyages in Sanmen Bay in December 2007 and June 2008, the density, dominant species and diversity of shrimp in the Sanmen Bay area during the winter and summer were studied. The spatial and temporal distribution of shrimp was analyzed, and the distribution of shrimp was analyzed according to the terrain and hydrology of the surveyed sea area. The results showed that the shrimp in Sanmen Bay area were mainly broad temperature and wide salt, the number of species in summer was higher than that in winter, and the average of shrimp quality and mantissa density in summer were also higher than those in winter. The shrimp quality in summer and winter were 93.32 kg / km2 and 31.97 kg / km2 respectively, while the mantissa densities were 32.34 × 103 ind / km2 and 19.32 × 103 ind / km2, respectively. According to the relative importance index (IRI) calculation, the dominant winter species in this area were Parapenaeopsis tenella and Oratosquilla oratoria in summer. The distribution of summer shrimp species was more uniform, which resulted in the lower winter shrimp quality and mantissa diversity index value H ’(1.58,1.33) in summer than the summer average and mantissa H’ average value (1.78,2.18). In winter, higher water temperatures in Sanmen Bay’s mouth caused more shrimp to appear. In the summer, there are mixed saltwater groups in the Bayou waters, which also make the species and quantity of shrimps more abundant here. According to the survey data, the number of shrimp species in Sanmen Bay waters accounts for 25.00% of the swimming shrimp in offshore Zhejiang, and its species richness is less than that in Zhejiang offshore.