【摘要】 鱼类种群结构和个体生长受水文、水环境和渔业捕捞等因素影响存在空间上差异，为了解珠江中下游广东鲂（Megalobrama terminalis）在不同水域（河口、坝上和坝下）种群结构和生长现状，2020年7-8月在珠江中下游共采集228尾广东鲂样本，测量体长、体质量，利用鳞片测定年龄，应用von Bertalanffy生长方程、Beverton-Holt模型和Pauly经验公式估算生长、死亡参数。比较分析结果显示，河口、坝下和坝上广东鲂优势体长分别为17.0～27.2、18.9～28.7和28.6～40.0 cm；优势体质量分别为93.0～447.9、148.8～480.0、39.5～1 420.8 g；年龄组成分别主要为3⁺（32.14%）、2⁺（24.11%）,3⁺（32.14%）、2⁺（24.11%）和4⁺（31.58%）、5⁺（26.32%）。河口、坝下和坝上广东鲂年龄生长方程分别为L=47.2(1-e^{-0.177（t+0.387）})、L=42.9(1-e^{-0.199（t+0.377）})和L=53.7(1-e^{-0.155（t+0.401）})。河口、坝下和坝上开发率E分别为0.410、0.373和0.248；临界体长L_c分别为25.1、23.0和28.4 cm。以上结果表明，广东鲂体长、体质量和年龄频率分布以及生长方程均存在空间上的差异。更多还原

【Abstract】 There are spatial differences in fish population structure and individual growth,which are affected by hydrology,water environment,and fishing.In order to study the population structure and growth differences of Megalobrama terminalis in the estuary,dam downstream,and dam upstream in the middle and lower reaches of the Pearl River,a total of 228 fish samples were collected in the middle and lower reaches of Pearl River from July to August in 2020.The body length and weight of the samples were measured,and the scales were used to determine the age.The von Bertalanffy growth equation,Bevertonholt model,and Pauly empirical formula were applied to estimate the growth and death parameters of M.terminalis.The results of comparative analysis showed that the dominant body length of M.terminalis was17.0-27.2 cm in the Pearl River estuary,18.9-28.7 cm in the dam downstream,and 28.6-40.0 cm in the dam upstream.The dominant body weight was 93.0-447.9 g in the Pearl River estuary,148.8-480.0 g in the dam downstream,and 39.5-1 420.8 g in the dam upstream.The dominant ages were 3⁺（32.14%） and 2⁺（24.11%） in the Pearl River estuary,3⁺（32.14%） and 2⁺（24.11%） in the dam downstream,and 4⁺（31.58%） and 5⁺（26.32%） in the dam upstream.The von Bertalanffy equation of M.terminalis was L=47.2 (1-e^{-0.177（t+0.387）}) in the Pearl River estuary,L=42.9 (1-e^{-0.199（t+0.377）}) in the dam downstream,and L=53.7 (1-e^{-0.155（t+0.401）}) in the dam upstream.The exploitation ratio （E） of M.terminalis was 0.410 in the Pearl River estuary,0.373 in the dam downstream,and 0.248 in the dam upstream.The critical length （L_c） was 25.1 cm in the Pearl River estuary,23.0 cm in the dam downstream,and 28.4 cm in the dam upstream.The results of comparative analysis showed that the frequency distribution of body length,body weight,age,and the growth equation of M.terminalis had spatial differences.更多还原