葛洲坝船闸过鱼时空特性研究

TEMPORAL CHARACTERISTICS OF FISH PASSING THROUGH THE GEZHOUBA SHIP LOCK

于2013年4月、6月及8月,在葛洲坝一、二号船闸上下闸首断面及闸室内,利用DIDSON声纳定点探测方法,对船闸上下行鱼类数量进行探测记录,并同步进行水质水动力现场监测,研究船闸过鱼现状及规律。结果表明:船闸天然情况下存在一定过鱼能力,附加一定的改进措施,船闸可能成为通航与过鱼功能合一的新型过鱼建筑物。船闸过鱼存在一定的昼夜节律,鱼类在夜晚时段表现的更为活跃,且在不同季节有选择相对适宜温度活动的趋势,而两船闸间下闸首天然鱼类通过量无显著差异。6月由于水温条件适合,且处于禁渔期末,鱼类大量繁殖,过鱼数量最大,4月及8月过高及过低的水温均不利于家鱼繁殖,过鱼相对较少,且均值比较无显著差异,另外不同月份水位流速变动可能对过鱼量造成一定影响。一号二号船闸的鱼类上闸首通过率分别为21%及42%。

This research investigated the actuality and regularity of fish passing in ship lock.In addition,the field water quality and hydrodynamic force were monitored by following fleet time when fish passing through ship lock at daytime(the period of 9∶00to 12∶00)in Gezhouba No.1ship lock and No.2ship lock from 29 th to 30 th August.Hydro-acoustic was applied to monitor fish passing in place of ship lock and upper lock head section.The investigation was carried out at downstream lock head section by hydroacoustic in all 24hours(the period of 9∶00to 9∶00the next day)during 21 th to 27 th April,18 th to 22 th June,23 th to 28 th August,2013.It is resulted that the ship locks have the ability of fish passing in natural condition,and they may become a new kind of fish passing building which not only has the navigation capacity but also the fish passing capacity by some improvement measures.The fish passing in ship lock performs circadian rhythm,fishes were more active at night compared with daytime,and expressed the tendency that to choose a relative suitable temperature for movement in different seasons,and it has no significant difference in the amount of fish passing in natural condition between the downstream lock head of two ship locks.Due to the suitable condition of water temperature and at the end of the forbidden fishing period of downstream of Gezhouba in June,fishes has mass rearing and the ship locks have the biggest amount of fish passing.In April and August,the water temperature was too low or too high so that it was not good for the rearing of the four major Chinese carps,leading to the comparatively small amount of fish passing,and it has no significant difference on the mean value after being compared.What's more,the change of water level and velocity in different month may have some effects on the amount of fish passing.The downstream fish density in two ship locks satisfied the need of fish passing ability in natural condition,and the difference of downstream fish density in two ship locks is not the key factor which limits the present fish passing ability of two ship locks.The fish can be induced to get in the ship locks from the downstream approach channel by taking fish some luring measures.As a result,the amount of fish passing in ship locks can be improved.A part of fishes keep staying in the ship locks after swimming inside the ship locks,because they did not get out of the ship locks when the water level rose.But they would swim downstream out of the ship locks back to downstream while the downstream ship lock gate opened again.It is explained that the upper lock head is the another key node of fish passing in ship locks,the upper threshold is the natural barrier for fish passing in ship locks.The fishing passing rate at upper lock head section were respective 21% and 42%in Gezhouba No.1ship lock and No.2ship lock.