吕泗渔场沿岸海域的虾类数量分布及其与环境的关系

Relationship of Shrimp Distribution with Environment in the Coastal Water of Lvsi Fishing Ground in Spring and Summer

本文根据吕泗渔场及附近海域2010年春季(5月)和夏季(9月)的渔业资源调查资料,研究吕泗渔场沿岸海域虾类资源密度的时空分布,分析优势种、水团、水深和水文等环境因素对虾类数量分布的影响。研究表明:5和9月,虾类重量密度为24.21和2.19kg·km-2,尾数密度为12.68×103和1.30×103ind·km-2。2个季节虾类资源密度的平面分布特征呈相同的规律,都是外部水域高于沿岸水域。5月,虾类主要优势种由葛氏长臂虾(Palaemon gravieri)、鲜明鼓虾(Alpheus distinguendus)和日本鼓虾(Alpheus juponicus)构成,其中葛氏长臂虾对尾数和重量的贡献率较大,为5月最重要的优势种;9月,虾类优势种由哈氏仿对虾(Parapenaeopsis hardwickii)、中华管鞭虾(Solenocera crassicornis)和葛氏长臂虾(Palaemon gravieri)构成,其中哈氏仿对虾对尾数贡献率最大,对重量贡献率较大,为9月最重要的优势种。运用回归分析方法,结合虾类资源的密度、温度、盐度及水深等环境因子,对调查海域虾类资源时空分布特征进行了研究。结果表明:吕泗渔场沿岸海域虾类数量的变化主要来自优势种的贡献;虾类资源密度季节变化特征与调查海域底温呈显著负相关;特殊的沙棘潮沟地形与虾类密度平面分布关系明显,较深的潮沟往往是虾类资源集中分布的区域。本研究对于认识吕泗渔场沿海虾类资源动态变化有一定的科学意义,同时也为掌握该海域渔场渔汛及虾类资源的合理开发和保护提供依据。

Lvsi fishing ground is located at the east sea area of Jiangsu Province,which is one of the most famous fishing grounds in China.The relationship between the distribution of shrimp resources and environment in the coastal waters of Lvsi fishing ground was determined in order to provide a scientific basis for the rational use of shrimp resources in this area.It has scientific significance to understand the dynamic change of shrimp resources in the Chinese coastal sea.Based on the surveying data of fish resources in the coastal area of Lvsi fishing ground in May and September,2010,we studied the spatiotemporal distribution of shrimp density and analyzed the effect of fishery resources,such as dominant species,current flow,water depth and environmental factors,aimed to explore the attributes of the fishing ground in this sea area.In May and September,the average of shrimp weight density was 24.21 and 2.19kg·km-2,respectively,while the figure for individual density was 12.68×10^3 and 1.30×10^3ind·km^-2,respectively.Both of the spatial distribution patterns were basically the same,being higher in the eastern than in the western water areas near the side of Rudong.Palaemon gravieri was the most dominant specie in May,whereas Parapenaeopsis hardwickii was the most dominant species in September.The stepwise regression analysis showed that dominant species had great contribution to the shrimp number density and weight density.Shrimp weight and individual density were significantly correlated with bottom water temperature,but less significantly with water salinity.Water depth was related to the distribution of shrimp density significantly,and the distribution of the density of regional resources was often focused on the high depth of the sea area.It was considered that sea area was an ideal feeding ground for economic fishes.Our findings will aid to finding out the change of fishery resource,and mastering the fishing season and providing reasonable basis of exploration and protection.