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天鹅洲故道水面面积为１３．７—３０．０ｋｍ２。据１９９１—１９９４年的调查，该故道具有以下优良性状：（１）水质好，溶解氧为５．７—１０．５ｍｇ／ｍｌ，透明度为０．３—１．７５ｍ。（２）水生生物丰富，共有１６门，３０６种。（３）鱼类种类繁多，计有９目１８科７７种。（４）家鱼资源丰富，性状优良。每年７—８月约有近２０万尾鲢、鳙、草、青鱼苗种进入故道育肥，其渔获量在７万ｋｇ左右；生长参数的比较分析证明，故道里的“四大家鱼”维持了其在长江的优良生长特性。总之，天鹅洲故道是建立鲢、鳙、草鱼、青鱼种质资源生态库的理想的自然场所。若把最初捕捞年龄从目前的１龄提高到３龄，把捕捞死亡率从０．６降低到０．３—０．５，并设置有效的拦鱼设备，预期可年产１０万ｋｇ或３—４万尾后备亲鱼。存在问题是：（１）竭泽而渔。对进入故道育肥的“四大家鱼”和就地繁生的鱼类的过度捕捞。（２）渔民过多。在故道打鱼为生的近５００渔民，转业困难，使该故道渔业生产处于恶性循环之中。这些问题如不解决，种质资源库势难建立。此外，从长远发展看，长江三峡高坝建成后，宜昌江段产卵场可能消失，以及故道的牛轭湖化，对天鹅洲故道作为种质资源天然生态库的影响都不容忽视。
The water surface area of the Tianwan Island is 13.7-30.0km2. According to the survey of 1991-1994, the old course has the following excellent traits: (1) good water quality, dissolved oxygen of 5.7-10.5 mg / ml and transparency of 0.3-1.75 m. (2) rich aquatic life, a total of 16, 306 species. (3) A wide range of fish species, accounting for 9 orders 18 families 77 species. (4) rich in fish resources, good traits. From July to August every year, there are about 200,000 silver carp and the hatching, grazing and breeding of black carp into the old course fattening. The catches are about 70,000 kg. The comparative analysis of growth parameters shows that the “four big fish” Its excellent growth characteristics in the Yangtze River. In conclusion, the old lane of the T’u-Chau Island is an ideal natural site for the ecological library of silver carp, bighead carp, grass carp and black carp germplasm resources. If the initial fishing age is raised from the current first to the third instars, the fishing mortality rate will be reduced from 0.6 to 0.3-0.5 and effective fish-stopping equipment will be provided, with an expected annual production of 100,000 kg or 3 -4 million reserve broodstock. The problems are: (1) exhausted Ze Ze fishing. Overexploitation of the “four major domestic fish” that have entered the fattening path of the old course and the fish that are locally produced. (2) Too many fishermen. Nearly 500 fishermen who make a living from fishing in the old course have difficulty in moving out of employment and the fishery production in the old course is in a vicious circle. If these problems are not solved, germplasm resources will not be established. In addition, from the perspective of long-term development, after the completion of the Three Gorges Dam in the Yangtze River, the spawning grounds of the Yichang Section may disappear and the oxbow lakes of the old course will have an impact on the natural habitat of the old lane of Swans Island as germplasm resources.