摘要
根据南海北部多齿蛇鲻生物学参数和20世纪80年代南海区底拖网选择性试验数据,运用Beverton Holt模型,分析在不同捕捞死亡系数F时,网囊网目尺寸从目前的平均27mm放大到39mm后多齿蛇鲻的单位补充量渔获量YW/R、单位补充量渔获尾数YN/R、渔获平均体长 LY、渔获平均体重 WY和渔获平均年龄 TY的变化情况。结果表明:网目尺寸放大后,在捕捞强度不变的情况下,YW/R、 LY、 WY、 TY的值均有不同程度的提高,且当前的捕捞死亡系数F越大,增幅越明显;YN/R,而的值却有所降低,降幅基本不受F的影响。F在0.4～3.0范围时,网目放大后多齿蛇鲻在年渔获尾数下降15%的情况下,产量反可增加11%～69%;同时 LY提高16%～30%、 WY提高31%～99%、 TY提高22%～50%。就39mm网目而言,F值为0.6时,多齿蛇鲻可获得最大产量。
Based on the biologic parameters of Saurida tumbil in Northern South China Sea and the data of the bottom trawl selectivity experiment in the 1980~,s, Beverton-Holt model is adopted to analyze the effects of mesh size adjusted from average 27 mm presently to 39 mm on the following indexes, such as the catch (in weight) per recruit (Y_W/R), catch numbers per recruit (Y_N/R), average body length of catch(_Y), average body weight of catch(_Y) and average age of catch (_Y) at different fishing mortality level. The results show that the value of Y_W/R, _Y, _Y and _Y all have a increase in different degrees, and the more higher the value of F at present, the more higher the increase rate. But the value of Y_N/R decreased, F almost had no effect on the decrease rate. If the range of F between 0.4～3, when the mesh size adjusted from 27 mm to 39 mm, the catch of Saurida tumbil may increase by 11%-69% at the precondition of the catch numbers decrease 15%; for the individuals, _Y may increase by 16%-30%, and _Y may increase by 31%-99%, and _Y may increase by 22%-50%. For the 39 mm mesh size, Saurida tumbil has the maximum catch when F is 0.6.
出处
《中国水产科学》
CAS
CSCD
北大核心
2004年第5期478-481,共4页
Journal of Fishery Sciences of China
基金
农业部渔业局水产行业标准化项目(2000230)
