细鳞鲑在太白山南坡的适应性生长研究

Ecological adaptations of Brachymystax lenok to the south Taibai mountain

【目的】研究细鳞鲑在太白山南坡黄柏塬地区的适应性生长情况,为太白山自然保护区珍稀濒危物种的适应性研究提供支持。【方法】在黄柏塬区域的湑水河、太白河及其支流,对细鳞鲑的栖息地特征、种群结构、生长状况以及分布进行调查。【结果】最近10年(1997-2007年)的年均气温较20世纪中后期(1970-1996年)升高1℃左右,细鳞鲑能够适应当地的生态环境,喜欢选择水流速度较缓(0.19～0.52m/s)、中午水底温度在6℃以上、水深35～112cm的环境中进行繁殖;细鳞鲑的洄游习性有所改变,迁移距离相对较短,甚至不迁移。所捕获的细鳞鲑年龄组成为1～4龄共4个年龄序列;多数雄鱼于2+龄达到性成熟,而雌鱼为3+龄;细鳞鲑体质量(W)和体长(L)关系符合Keys增长函数-W=0.045L-2.725。对细鳞鲑体长和体质量的实测值进行回归,可得VonBertalanffy生长方程的参数为:渐进体长L∞=42.12cm,渐进体质量W∞=1202.11g,生长系数k=0.134,理论起始生长年龄t0=-0.517。细鳞鲑群体垂直分布表现出高年龄个体多分布于海拔高处的趋势。【结论】细鳞鲑对黄柏塬山地气候和生境具有良好的适应性。

[Objective] The study observed the ecological adaptations of Brachymystax lenok in Huangbaiyuan area of the south Taibai mountain in order to provide technological support to the adaption of rare animals to changing climate for national Taibai mountain natural reserve.[Method] The research site was located in Xushui river,Taibai river and their tributary in Huangbaiyuan area of the south Taibai mountain.The habitat,population structure,growth and distribution of Brachymystax lenok were investigated.[Result]...