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本文研究长江中下游长吻的种群生态学特性并进行渔业生物学分析。胸鳍棘、尾舌骨及脊椎骨都可用作年龄鉴定材料。用Brody-Bertallanffy的公式表述体长、体重与年龄的关系。调查生殖特性并分析比较产卵力及产卵群体的结构类型。以食物出现率和重量法评价各类食物在食料中的作用。由渔获物统计资料计算种群的自然死亡率和捕捞死亡率。通过比较各种捕捞强度和最小捕捞规格的不同的总渔获量和繁殖群体的相对数量,提出获得最大持续渔获量的捕捞强度和最小捕捞规格。
In this paper, the population ecology characteristics of S. longissimus in the middle and lower reaches of the Yangtze River were studied and the fishery biology was analyzed. Pectoral spines, tail hyoid and vertebral bone can be used as age identification material. Brody-Bertallanffy formula for body length, body weight and age. Investigate reproductive traits and analyze the structures of the oviposition and spawning populations. Evaluate the role of various foods in foodstuffs by the food appearance rate and gravimetric method. Natural catch and fishing mortality were calculated from catch statistics. The fishing effort to obtain the maximum sustainable catch and the minimum fishing catch are proposed by comparing the different total catches and the relative numbers of breeding stock for various catch strengths and minimum fishing specifications.