| 引用本文: | 谭细畅,李跃飞,李新辉,李捷,王超.梯级水坝胁迫下东江鱼类产卵场现状分析.湖泊科学,2012,24(3):443-449. DOI:10.18307/2012.0317 |
| TAN Xichang,LI Yuefei,LI Xinhui,LI Jie,WANG Chao.The status of fish spawning ground in the East River with cascade dams' duress. J. Lake Sci.2012,24(3):443-449. DOI:10.18307/2012.0317 |
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| 摘要: |
| 东江作为珠江流域重要支流之一,是香港地区以及珠江三角洲东部地区重要水源.鱼类不仅是河流生态系统重要组成也是其健康状况的重要指示生物.目前东江已经修建了一系列水坝,基于东江河流生态系统健康维持和管理的需要,有必要了解河流中鱼类产卵场的现状.据此,2010年3-10月对东江古竹江段的鱼苗(卵)进行了连续采集,目前鱼苗种类已鉴定到26种(属),主要优势种类为鰕鯱(63.0%)、赤眼鳟(16.8%)、尼罗罗非鱼(9.7%)、大眼鳜(2.0%)等;调查期间古竹江段鱼苗(卵)径流量初步估算为11.4×108尾(颗),东江鱼类主要繁殖期为4-9月.与东江历史资料及西江江段鱼类繁殖现状相比较,东江鱼类产卵场功能极度退化,不仅鱼类产卵规模已明显下降,并且东江古竹江段鱼苗中洄游性种类缺失;本次调查证明东江龙川江段原有的四大家鱼产卵场已经消失;通过典范对应分析分析表明,东江江段鱼类产卵繁殖对水文生态因子的响应程度较低,说明东江江段水文节律受梯级水坝影响程度大,偏离了鱼类产卵繁殖的生态需求.尼罗罗非鱼在东江古竹江段有暴发性繁殖现象,东江已经面临外来种的严峻威胁,分析认为梯级水坝的修建是导致罗非鱼暴发性增长的主要原因之一.根据目前东江鱼类产卵场现状,建议把鲢、鳙及广东鲂列入增殖放流的品种目录,加强人工增殖放流;从贯通鱼类洄游通道及修复产卵场的需求上考虑,建议在东江各水坝上补建鱼类过鱼通道. |
| 关键词: 鱼类产卵场 东江 梯级水坝 胁迫 古竹段 |
| DOI：10.18307/2012.0317 |
| 分类号: |
| 基金项目:国家水体污染控制与治理科技重大专项项目(2009ZX07211-009)资助 |
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| The status of fish spawning ground in the East River with cascade dams' duress |
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TAN Xichang, LI Yuefei, LI Xinhui, LI Jie, WANG Chao
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Pearl River Fishery Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510380, P. R. China
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| Abstract: |
| As the eastern tributary of the Pearl River in Guangdong Province, southern China, East River is a major source of water supply for Hong Kong and Shenzhen. Besides their important role in nutrient cycling and transformation in the river ecosystem, fish are also considered as good indicators of aquatic ecosystem health. For the purposes of assessment and management of East River it is necessary to look into the status of fish spawning ground, especially with cascade dams' duress. From March to October, 2010, we studied taxonomic composition and daily variation of fish larvae abundance from a survey in the Guzhu section of East River over a period of 8 months, and collected 26 species (or genera). The fish larval samples were numerically dominated by four species, Gobies (Gobiidae) 63.0%, Barbel Chub (Squaliobarus curriculus) 16.8%, Tilapia (Tilapia mossambica) 9.7%, and Mandarin (Siniperca kneri) 2.0%. These four species accounted for 91.5% of total numbers. During the sampling period, the total fish larvae abundance was estimated as 1.14 billion. When compared with historical records from the 1950s' and the currently condition of fish larvae in the West River, there are obvious degradation in the fish larvae community in East River, which means no migratory species and irregular response to the hydrological variation. It comes to the conclusion that the cascade dams blocked the fish migration and caused the disappearing of some spawning grounds. Our results clearly show that Tilapia larvae outbreak in the East River, which is very dangerous to the ecology safety. We also conclude that construction of cascade dams makes the East River more habitable for Tilapia. For the purpose of protecting ecosystem, we recommend that more Silver Carp (Hypophthalmichthys molitrix), Bighead Carp (Aristichthys nobilis) and Black Guangdong Bream (Megalobrama terminalis) be released to the East River and possibly constructions of fish passage be considered. |
| Key words: Fish spawning ground East River cascade dams duress Guzhu section |
