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对珠江河口及其附近水域银鲳的生长与死亡参数进行估算,得von Benalanffy生长方程的相关参数为: L∞=36.0 cm,K=0.230,t0=-1.137;根据生长方程进一步计算得到自然死亡系数为0.586;20世纪90年代捕捞死亡系数为0.944,是20世纪80年代的近2倍;根据等渔获量曲线图分析,若在当前的捕捞规格(开捕叉长为12.0 cm)下仍维持现行的捕捞强度(捕捞死亡系数),资源将受到破坏,而且不符合经济效益的要求。依据性成熟特征,开捕叉长最小应为15.0 cm;综合考虑性成熟特征、当前可能的捕捞强度及经济效益,在提高产量而不破坏资源的前提下,建议珠江河口及附近水域银鲳的开捕叉长应由12.0 cm增加至15.0 cm。
The parameters of the growth and mortality of Agkistrodon ophilus in the Pearl River estuary and its adjacent waters were estimated. The relevant parameters of the von Benalanffy growth equation were: L ∞ = 36.0 cm, K = 0.230, t0 = -1.137; natural death was further calculated according to the growth equation Coefficient of 0.586; fishing mortality factor of 0.990 in the 1990s was 0.944, nearly two times that of the 1980s; According to the analysis of the catches and other fishing curves, if the current fishing specifications (opening length 12.0 cm) Maintaining the current fishing intensity (fishing mortality) will destroy the resources and will not meet the economic benefits. According to sexual maturity characteristics, the minimum length of the open forks should be 15.0 cm. Considering the sexual maturity characteristics, current fishing intensity and economic benefits, it is suggested to increase the yield without destroying the resources. The length of the open forks should be increased from 12.0 cm to 15.0 cm.