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近年来由于长江鲥鱼产量变动较大,迫切要求查明原因。正确鉴定年龄,是研究鲥鱼资源变动、生长、繁殖、生活习性等必不可缺的基础工作,国内曾对鲥鱼做过调查,但多限于一般生物学研究,而年轮特征的专门研究未见报道,为此,我们只得尝试,并用鳞片上的年轮进行了大量的年龄鉴定工作。现将研究结果整理成文,但因鲥鱼平时栖息在海洋里,只有每年4-8月才进入长江作生殖洄游,因此在取材上,受到了一定的条
In recent years due to large fluctuations in the production of anchovy in the Yangtze River, an urgent need to identify the cause. Correctly identifying the age is a necessary basic work for studying the changes, growth, reproduction and living habitat of mandarin fish. However, surveys of mandarin fish have been conducted in China, but most of them are limited to general biological research. However, the special research on the characteristics of annual rings As reported, for this reason we have to try and carry out a large number of age appraisals with the annual rings on scales. Now the research results are collated, but because the mullet usually habitat in the sea, only from April to August each year to enter the Yangtze for reproductive migration, so in drawing, by a certain article