Variation in primary productivity has been described for an extensive range of natural systems and may lead to remarkable bottom-up effects on consumer communities at higher trophic levels. During a standardized sampling of the small mammal assemblage in the Reserva Florestal Morro Grande, SP, Brazil, we documented a bamboo blooming followed by an increase in abundance of small mammals. Here we described the effects of this blooming of the assemblage of small mammals and evaluated if (i) the abundance of frugi-/granivore species is affected more strongly than the abundance of insect-/omnivore species and (ii) due to the massive food availability in the habitat (bamboo seeds), body mass index of one of the affected species, the rodent Euryoryzomys russatus, will increase after the bamboo blooming. Although some species became more abundant, the difference was not related to species diet. We did find a significant increase in the body weight of Euryoryzomys russatus after the bamboo blooming. We emphasize that an infrequent and poorly known event like bamboo blooming can have a major impact on rodent population dynamics, regardless of the species diet, increasing abundance, and weight bottom-up controlled by the massive availability of food resources.

中文翻译：

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自下而上的效果：新热带雨林中的竹子盛开后，啮齿动物爆发

已经描述了广泛的自然系统初级生产力的变化，并可能在较高营养水平下导致对消费者社区的显着的自下而上的影响。在巴西SP Reserva Florestal Morro Grande的小型哺乳动物组合的标准化采样中，我们记录了竹花盛开，随之而来的小型哺乳动物数量增加。在这里，我们描述了这种小型哺乳动物种群繁盛的影响，并评估了（i）节食/食肉动物物种的丰度是否比昆虫/杂食动物物种的丰度受到的影响更大，以及（ii）由于食物过多而受到的影响栖息地的可用性（竹子种子），受影响物种之一的体重指数，啮齿类Euryoryzomys russatus，竹开花后会增加。尽管某些物种变得更加丰富，但差异与物种饮食无关。我们确实发现竹开花后，Euryoryzomys russatus的体重显着增加。我们强调，很少发生且鲜为人知的事件（如竹花盛开）可能对啮齿动物种群动态产生重大影响，而不论物种饮食，食物的丰度增加以及食物资源的大量供应所控制的体重自下而上。