种群年龄组成

结论影响种群数量变动的主要因素有种群年龄组成中幼年组的百分比、怀孕率、繁殖指数以及该地区子午沙鼠、三趾跳鼠和黑线仓鼠的数量。

Conclusion The important elements of population dynamics were the population age structure , the pregnant rate , the reproductive indices and the population number of other species ( little Chinese jird , northern three-toed jerboa and striped hamster ) .

界于两者之间为亚成年组。还探讨了小家鼠种群年龄组成的变化及其与种群密度的关系；

There are obvious relationships between the age composition of population and the population density .

北京地区黑线仓鼠年龄鉴定及种群年龄组成的研究

Study on the division of age group and the age composition of population of Striped Hamster in Beijing area

社鼠、针毛鼠的种群年龄组成初步研究（啮齿目：鼠科）

A preliminary study of the age structure in the populations of the mountain rats , rattus Niviventer confucianus and Rattus fulvescens huang ( rodentia : Muridae )

宁波三山滩涂珠带拟蟹守螺种群的年龄组成与生长

Age Composition and Growth of Cerithidea Cingulatus in Ningbo Coast