长江上游江津江段长薄鳅种群参数和资源量评估
发布时间：2018-03-24 10:10
本文选题：种群参数 切入点：生长 出处：《动物学杂志》2016年06期
【摘要】：长薄鳅(Leptobotia elongata)为长江上游特有种,由于过度捕捞和大坝建设,其种群生存受到极大威胁,已被《中国物种红色名录》列为易危物种。为了解三峡工程蓄水后该物种的种群动态,利用2007~2009年三峡库区以上江津江段的渔获量和体长频率数据评估了其生长和死亡参数、资源量及资源利用。长江上游江津江段长薄鳅体长范围为76~480 mm,体重范围为5~2 002 g,平均体长为(158.7±54.8)mm,平均体重为(72.4±148.8)g。优势体长组为90~210 mm,约占总数的77.9%(n=277)。长薄鳅体长(L,单位mm)与体重(W,单位g)幂函数关系为:W=7.28×10㧟6L3.09(R~2=0.95,P0.01,n=277)。由体长频率法拟合出长薄鳅渐近体长(L_∞)为555 mm,生长系数(k)为0.17/a。由Pauly经验公式估算出其自然死亡系数(M)为0.37。由长度转渔获物曲线估算出其总死亡系数(Z)为1.23。江津江段长薄鳅资源开发率为0.70,超过了其资源最大开发率0.43,表明其资源已过度开发。由体长结构实际种群分析估算出江津江段2007、2008和2009年长薄鳅年资源量分别为2 544尾/km(0.75 t/km)、2 405尾/km(0.42 t/km)和7 245尾/km(1.63 t/km),平均4 065尾/km(0.93 t/km)。与以往研究相比,本研究记录到了长薄鳅的最大个体(体长480 mm);本研究估算的长薄鳅总死亡系数和资源开发率较高,可能与江津江段的捕捞强度较高有关。建议加强长薄鳅种群动态长期监测,采取禁渔、人工增殖放流等措施促进资源恢复。
[Abstract]:Leptobotia elongata is a endemic species in the upper reaches of the Yangtze River. Because of overfishing and dam construction, its population survival is greatly threatened and has been listed as a vulnerable species in the Red list of species of China. In order to understand the population dynamics of the species after the three Gorges Project impoundment, The growth and death parameters were evaluated by using the catch and body length frequency data of Jiang Jin section above the three Gorges Reservoir area from 2007 to 2009. Resource quantity and resource utilization. The body length and body weight range of the long and thin Loach in Jiang Jin section of the upper reaches of the Yangtze River are 76480mm, 52.002g, 158.7 卤54.8mm, and the average body weight is 72.4 卤148.8mm. the dominant body length group is 90,210mm, which accounts for about 77.9nc277m of the total amount of Loach. The power function relation with weight W, unit g is 7. 28 脳 10? The Asymptotic length of Loach (L _ 鈭，
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