摘要
根据2009—2010年在东海区捕获的鲐鱼样本,产生6龄12个月的模拟数据,分析由于渔具选择或取样过程中人为因素等导致渔获样本体长频率结构可能出现的偏差对使用FiSATⅡ软件估算丰满系数和渐近体长产生的影响情况。模拟研究内容包括渔获物样品数量对评估结果的影响,以及当渔获样本中小个体偏少和大个体缺失两种情况所导致评估结果的偏差情况。结果显示,渔获样品中的大个体样本对评估结果的准确性十分重要。当渔获样本数量较小,或者样本中小个体偏少时,样品中能够包含最大体长组时,估算得到的丰满系数和渐近体长与真值非常接近。但样品中大个体缺失时,即中、小个体较多,参数估计值与真实值有较大差异,其中丰满系数估计结果偏小,而渐近体长值估计结果偏高。因此,在使用FiSAT II软件估算生长参数时,所使用的渔获样本的体长频率分布应尽量与资源量群体体长结构组成一致,并且需保证最大体长组不能缺失,这样可得到较为准确的丰满系数和渐近体长的估计值,从而保证在进一步的资源量和渔获量等评估工作中得到准确的结果。
Simulation data of 6 ages and 12 months were developed based on mackerel （Scomber j aponica） samples collected from the East China Sea during 2009 and 2010 .The impacts of length frequency biases , w hich usually come from the fishing selectivity or man‐made factors ,on the estimates of grow th parame‐ters （L∞ and K） when using FiSAT Ⅱ ,were analyzed .Scenarios of fewer smaller fishes and lack of larger fish were considered in the simulation analyses .The results showed that the larger fishes in the sample were critical to the accuracy of estimation .When there were fewer data or fewer smaller individuals in the samples ,the estimated L∞ and K were very close to the true values if the largest length group was availa‐ble .However ,when larger individuals were absent in the samples ,the estimated parameters were differed greatly from the true values .The estimated L∞ was smaller than the true value ,while K was larger . Therefore ,when FiSAT Ⅱ is applied to the estimation of growth parameters ,the distribution of length frequency in the sample should be accordance with that in the population ,and make sure that the largest length group is available in the sample .In this way , L∞ ,K ,and the abundance and catch in further as‐sessment can be accurately obtained .
出处
《水产科学》
CAS
北大核心
2014年第5期277-282,共6页
Fisheries Science
基金
浙江省自然科学基金资助项目(LY13D010005)
浙江省本科院技中青年学科带头人学术攀登项目(Pd2013222)
浙江省大学生科技创新活动计划暨新苗人才计划项目(2013R411007)
关键词
体长频率
生长参数
FiSAT
Ⅱ
偏差
鲐鱼
length frequency
growth parameter~ FiSAT II
bias
Scomberjaponica
