黑水河下游鱼类资源现状及其保护措施

为了解白鹤滩蓄水运行前黑水河下游鱼类资源的现状、受到的主要威胁及其保护措施,于2014年1~12月在黑水河下游干支流江段采用电捕法进行了渔获物调查。结果显示:12个月共调查发现鱼类28种,隶属于3目8科23属,其中喜流水生境、产粘沉性卵、以着生藻类或/和底栖动物为食物的鱼类种类较多;调查区域鱼类个体规格普遍较小,其中齐口裂腹鱼Schizothorax prenanti、短体副鳅Paracobitis potanini、红尾副鳅Paracobitis varigatus、短须裂腹鱼Schizothorax wangchiachii、前鳍高原鳅Triplophysa anterodorsalis、中华纹胸鮡Glyptothorax sinense和凹尾拟鲿Pseudobagrus emarginatus为调查区域的主要经济鱼类;上半年和下半年的渔获物结构在统计学上差异显著(R=0.81,p=0.1%0.05),鱼类在金沙江干流和黑水河下游之间的相互迁徙比较明显;CPUE呈现先波动下降然后逐月上升的趋势,其中10月份的CPUE最低;丰度生物量比较曲线显示2014年各月的渔获物结构均处于严重干扰状态。黑水河下游河道采砂以及过度捕捞是白鹤滩蓄水前影响黑水河下游鱼类资源的主要因素,建议通过控制采砂的江段、采砂的时间以及全面禁捕保护该区域的鱼类资源。

FISH RESOURCE STATUS OF THE LOWER REACHES OF THE HEISHUI RIVER AND THE MEASURES FOR THEIR CONSERVATION

In order to better understand the status,main threats and conservation measures of fish resources of the lower reaches of Heishui River before the operation of the Baihetan hydropower station,a catch survey using the electrofishing equipment was conducted monthly from January to December in 2014.The results showed that:a total of 28 species of fish belonging to 3 orders,8 families and 23 genera were collected during the 12 months,among them many fish species were the ones that prefer to running water,spawn the sticky and demersal egg and feed mainly on periphyton or/and benthic organism.The fish individuals were generally dominated by small size ones and the main economic fishes in the investigated area were Schizothorax prenanti,Paracobitis potanini,Paracobitis varigatus,Schizothorax wangchiachii,Triplophysa anterodorsalis,Glyptothorax sinense and Pseudobagrus emarginatus.The catch structures between the first half and the second half of this year were statistically significant (R=0.81,p＜0.05) and the mutual migration between the mainstream of the Jinsha River and the lower reaches of the Heishui River was obvious.The values of the catch per unit effort (CPUE) firstly displayed fluctuated decline and then showed a monthly increasing trend,and the value of CPUE on October was lowest among 12 months.The abundance biomass comparison curves showed that the catch structure were in a state of severe disturbance in the months of 2014.Before the filling of the Baihetan Reservoir,the sand extraction and overfishing were the main factors that affected the fish resources of the lower reaches of Heishui River,thereby the protection measures including the controls for the sections and times of sand extraction and the comprehensive fishing ban in the lower reaches of the Heishui River should be applied for protecting the fish resources of this region.