海北高寒草甸金露梅灌丛根田鼠种群生产力的研究 Ⅱ.种群生产量

PRODUCTIVITY INVESTIGATION OF THE ROOT VOLE (MICROTUS OECONOMUS) POPULATION IN THE HAIBEI ALPINE BUSHLAND (POTENTILLA FRUTICOSA)Ⅱ.POPULATION PRODUCTION

本文探讨了青海海北高寒草甸生态系统中根田鼠种群的生产力。野外工作采用标志重捕法(CMR),利用个体周转率(θN)、繁殖—生长生产量(P=P_r+P_g)和生长—存活曲线估算了两块样地上根田鼠种群1980—1982年3年间的生产量。根田鼠种群生产量的年间动态和重要的生态效应有:3种方法算得的各年生产量与个体日、平均密度及新生个体数成正比例;比值P_g/p与生态寿命、密度等有关;可捕年龄前动物的生产量在总量中所占比例很大(达81％);繁殖生产量P_r的季节动态表观为5月低、6月高、7月下降的倒"V"字型。

The productivity of the root vole (Microtus oeconomus) population in the Haibei alpine meadow ecosystem of Qinghai was studied. The catch-mark-release (CMR) method was used in field works for three years (1980-1982), the net production of the root vole population was estimated with individual turnover rate (ON) , reproductive growth production (Pr+Pg) and growth survival curve on two plots. The article emphatically analyses dynamics of the population production during three years and some important ecological efficiencies are shown: there was no much difference in the productions that were obtained by the three methods, but there were great annual variations; the production was proportional to individual-days. average density and number of newborns, the value Pg/P related with the mean longevity and population density, about 81% of the total was made by the nontrappable animals (nestlings and suckings); the reproductive production (Pr) was low during May, high during June, and dropped during July.