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机构地区:[1]四川省中医药研究院药物种植研究所,南川648408
出 处:《中国中药杂志》1990年第12期4-5,共2页China Journal of Chinese Materia Medica
摘 要:通过实地考察,乌龟自然资源自60年代以来有逐年减少的趋势。原因是:除人为的无计划滥捕滥杀外,还有自然因素的影响,导致雌龟数量显著大于雄龟量,致使自然繁殖率降低。Our on-the-spot investigation has indicated that the tortoise population as natural resources has been on the decrease ever since the sixties. The reason for the decrease lies in some natural factors as well as the indiscriminate catching and killing by man. As a result, the female tortoises remarkedly over whelm the male ones in number, which leads to a drop in the natural rate of breeding.
分 类 号:S865.49[农业科学—野生动物驯养]
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