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现阶段,东海传统的渔业种类普遍缺乏年龄结构数据,数据有限方法的应用对于研究生活史特征和种群状态都十分重要。日本鲭是浙江南部近海海域的优势物种之一,本研究依据2016—2020年该海域的渔业资源调查数据,利用基于叉长数据的数据有限方法估算日本鲭生活史参数,同时利用单位补充量渔获量模型(YPR)评估了日本鲭的资源状态。结果表明:1606尾日本鲭样品的叉长(L)和体重(W)的关系为W=4.18×10-3L3.28(R2=0.96);日本鲭von Bertalanffy生长方程中的渐近叉长为28.34 cm,生长速率为0.36 a-1,理论初始年龄为-0.40 a。现阶段,日本鲭的总死亡系数为1.67 a-1,自然死亡系数(M)为0.85 a-1,捕捞死亡系数(F)为0.82 a-1,开发率为0.49。当前开捕年龄为1.78 a,开捕叉长为15.44 cm。YPR模型结果显示,随着F增大,YPR值呈现先上升后下降的趋势,生物学参考点F 相似文献
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MOSTAFA HAGHANI YAGHOUB FATHIPOUR ALI ASGHAR TALEBI VALIOLLAH BANIAMERI 《Insect Science》2006,13(6):477-483
Reproduction and population parameters of vegetable leafminer, Liriomyza sativae Blanchard were measured on cucumber (Cucumis sativus L.) at seven constant temperatures (10, 15, 20, 25, 30, 35 and 40℃). No eggs were found at 10℃ and flies died after exposure to 40℃. The significantly highest intrinsic rate of natural increase (rm), net reproductive rate (R0) and finite rate of increase (λ) ofL. sativae were obtained at 25℃ as 0.196, 52.452, and 1.216, respectively. The above-mentioned parameters decreased at 15℃ and 135℃ and this reduction at 35℃ was strong. Doubling time (DT) varied significantly with temperature. The shortest doubling time was obtained at 25℃. Mean generation time (T) decreased significantly with increasing temperature between 15℃ and 35℃. Percentage of immature ages in the stable age distribution was more than 95% at all temperatures. Female longevity was greater than male at all temperatures. Liriomyza sativae lived for a long time at 15℃, whereas at 35℃ had lower survival rates. The effect of temperature on reproduction, especially the intrinsic rate of increase of L. sativae would be useful for predicting its longterm population fluctuation over several generations. 相似文献