摘要: |
本围隔由浮体、围隔袋,底盘、内网和搅水机等5部分组成。围隔袋呈圆筒形,由聚乙烯编织布缝合而成,高5.9m,容水量14.3 m2。底盘是围隔的底部。内网与围隔袋相套合,供检查鱼和捕鱼之用。搅水机的动力是90W的电动机,其作用是定时搅水,以保持围隔内水的混合与围隔外大水体基本一致。灌水采用“沉下提上法”,每灌一个围隔只需10余分钟。使用结果证明,本围隔性能良好,操作简便而又牢固安全。 |
关键词: 内陆水域生态 浮式围隔 |
DOI: |
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基金项目:国家水利部水利技术开发基金资助,管H8905号 |
附件 |
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A FLOATING ENCLOSURE DEVICE SUITABLE FOR INLAND WATER ECOLOGICAL EXPERIMENTS |
Li Deshang, Xiong Bangxi, Li Qi, Yuan Junfeng
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College of Fisheries, Ocean University of Qingdao 266003
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Abstract: |
The device was designed and applied in 1990 to study the carrying capacity of reservoirs for feeding-cage-culture of fish. Two successful batches of experiments proved the device is reliable and convenient for operation.
The device consists of five parts: a steel framed buoyan body equipped' with platic floats; a cylindrical polyethylene coated with density plastic woven cloth enclosure bag, 5.7 m in height, 6 m in girth, 2.86 m2 in area and 14.3 m3 in capacits; a steel framed, plastic woven cloth covered basal plate which is the bottom of the enclosure; an inner net inside the enclosure bag nclosure; an inner net inside the enclosure bag, used to catch / examine experimental fish, and a 90 W mothor operated water. stirre fixed at the center of the bag mouth, used to stin the water in the bag periodically to keep the water mixing inside the bag equal to that outside it.
To fill the enclosure a “sinking and rising" method is used. In this method first the enclosure is made depressed so as to keep the buoyant body (with no floats at the time) resting directly on the basal plate and sunk to the 5m depth; then the buoyant body is pulled up out of the water surface with the basal plate left unmoved by its weight, so that the enclosure is filled with a water column equal to that outside it. The enclosure is equipped with floats and anchored on the chosen site at last.
The water stirrer operated for 50 min at 10:00 a.m. and 15:00 p.m. whenever the weather is calm or nearly calm. Observations showed that this was enough to keep water mixing inside the enclosure equal to that outside it.
The maximum light shading rate of the enclosure was about 26.7% at the beginning and 33.3% in the end. The chief problem was the periphyton (especially epiphyton) which propagate on the inner surface of the enclosures, interfering with the illumination and water quality of the enclosures. The authors suggest manuallybrushing it off periodically or stocking certain fish which feed on periphyton in them as measures to solve it. |
Key words: Inland water ecology, Floating enclosure |