In warm temperate forests where light availability is generally low, roadsides often provide a refuge for myrmecochores. Therefore, whether or not ants disperse seeds along the roadsides should critically affect the regeneration of myrmecochores. Nonetheless, the dispersal behaviors of ants along roadsides have rarely been investigated in warm temperate forests. This study examined the road preference of two seed dispersing ants in warm temperate Japan, Formica japonica and Pheidole nodus. We located ant nests using baits placed at the vicinity of myrmecochorous sedges and examined the road preferences of ants and their consequences for seed dispersal by comparing the observed road proximity of ant nests with the simulated value assuming a random dispersal direction. Nests of both ant species were significantly closer to the road than in those simulated assuming random dispersal, which confirmed their road preferences. The road preference of F. japonica reduced the risk of seed loss into the forest interior to one-ninth of the random dispersal. This trend was not observed in P. nodus due to its short dispersal distance relative to roadside width. Although light availability was higher around nests of P. nodus due to their closer proximity to the road than nests of F. japonica, adult sedges were located farther from the road than the nests of P. nodus. This implies that nests of P. nodus are unsuitable microhabitats for sedges. These results suggest that ants can disperse seeds along forest roadsides in warm temperate forests, but the efficiency vary among ant species.

中文翻译：

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蚂蚁在日本暖温带森林中的道路偏好及其对食虫莎草再生的影响

在光照普遍较低的暖温带森林中，路旁通常为昆虫纲动物提供避难所。因此，蚂蚁是否在路边散播种子应该严重影响myrmecochores的再生。尽管如此，在暖温带森林中很少研究蚂蚁在路边的扩散行为。本研究调查了日本暖温带的两种种子传播蚂蚁——福米卡 (Formica japonica)和Pheidole nodus的道路偏好。. 我们使用放置在蚁巢莎草附近的诱饵来定位蚂蚁巢穴，并通过将观察到的蚂蚁巢穴的道路接近度与假设随机散布方向的模拟值进行比较，检查蚂蚁的道路偏好及其对种子散布的影响。与假设随机分布的模拟相比，这两种蚂蚁的巢穴都更靠近道路，这证实了它们的道路偏好。F. japonica的道路偏好将种子流失到森林内部的风险降低到随机散布的九分之一。在P. nodus 中没有观察到这种趋势，因为它相对于路边宽度的扩散距离较短。尽管P. nodus巢穴周围的光照充足由于它们比F. japonica 的巢更靠近道路，成年莎草的位置比P. nodus的巢离道路更远。这意味着P. nodus 的巢穴不适合莎草的微生境。这些结果表明，蚂蚁可以在暖温带森林的林道旁传播种子，但效率因蚂蚁物种而异。