Mayfly assemblage structure, microhabitat preference and emergence patterns were studied over a decade in two types of karst freshwater habitats, namely, a spring and two tufa barriers. Mayfly adults were collected using pyramidal emergence traps. A total of nine species was recorded. Tufa barriers had a higher species richness but a lower abundance than did the spring. All sites were dominated by species typical of the rhithral zone. The spring had the highest share of grazers, whereas gatherers (collectors and filter feeders) dominated at tufa barriers, with minimal changes through the years. Mayfly abundance at the spring was higher in years with a higher discharge. The opposite was recorded for tufa barriers, which could be related to drift and food availability. Mayflies emerged from the spring between March and November, most probably being triggered by the photoperiod. Emergence from tufa barriers was seasonal and related to changes in water temperature. Some species exhibited typical central European emergence patterns, whereas, in some others, certain discrepancies were recorded. Several taxa showed preference towards emergence from a particular microhabitat. The present study showed that for fine ecological data on aquatic insects, long-term studies are essential.

中文翻译：

---

对蜉蝣出现模式的长达十年的研究

十多年来，在两种类型的喀斯特淡水栖息地，即一个泉水和两个凝灰岩屏障中，研究了蜉蝣的组合结构、微生境偏好和出现模式。蜉蝣成虫使用金字塔形出现陷阱收集。共记录了九种。与春季相比，灰岩屏障的物种丰富度更高，但丰度更低。所有站点都以典型的rhithral区物种为主。春季的食草动物比例最高，而采集者（收集者和滤食者）在凝灰岩屏障中占主导地位，多年来变化很小。春季的蜉蝣丰度在排放量较高的年份较高。凝灰岩屏障的记录正好相反，这可能与漂移和食物供应有关。蜉蝣从春天的三月到十一月出现，很可能是由光周期触发的。凝灰岩屏障的出现是季节性的，与水温的变化有关。一些物种表现出典型的中欧出现模式，而在其他一些物种中，记录了某些差异。几个分类群表现出倾向于从特定的微生境中出现。目前的研究表明，对于水生昆虫的精细生态数据，长期研究是必不可少的。