Temporal variability of plant–pollinator interactions is important for fully understanding the structure, function, and stability of plant–pollinator networks, but most network studies so far have ignored within-day dynamics. Strong diel dynamics (e.g., a regular daily cycle) were found for networks with Cichorieae, which typically close their flowers around noon. Here, we experimentally prevented early flower closure to test whether these dynamics are driven by the temporally limited availability of Cichorieae, or by timing of pollinator activity. We further tested if the dynamics involving Cichorieae and their pollinators also affect the dynamics on other plants in the network. Finally, we explored the structure of such manipulated networks (with Cichorieae available in the morning and afternoon) compared to unmanipulated controls (Cichorieae available only in the morning). We found that flower closure of Cichorieae is indeed an important driver of diel network dynamics, while other drivers of pollinator timing appeared less important. If Cichorieae flowers were available in the afternoon, they were visited by generalist and specialist pollinators, which overall decreased link turnover between morning and afternoon. Effects of afternoon availability of Cichorieae on other plants in the network were inconclusive: pollinator switching to and from Cichorieae tended to increase. On the level of the aggregated (full-day) network, the treatment resulted in increased dominance of Cichorieae, reducing modularity and increasing plant generality. These results highlight that network dynamics can be predicted by knowledge of diel or seasonal phenology, and that fixed species timing assumptions will misrepresent the expected dynamics.

植物-传粉媒介相互作用的时间变化对于充分理解植物-传粉媒介网络的结构、功能和稳定性很重要，但迄今为止大多数网络研究都忽略了日内动态。对于菊科植物的网络，发现了强烈的昼夜动态（例如，有规律的每日周期），菊科植物通常在中午左右关闭花朵。在这里，我们通过实验阻止了早期的花朵关闭，以测试这些动态是否是由菊科植物的时间有限的可用性或传粉媒介活动的时间驱动的。我们进一步测试了涉及菊科植物及其传粉者的动态是否也会影响网络中其他植物的动态。最后，与未操纵的对照（菊苣科仅在上午可用）相比，我们探索了这种操纵网络（菊苣科在上午和下午可用）的结构。我们发现菊科植物的花闭确实是昼夜网络动态的重要驱动因素，而传粉媒介时间的其他驱动因素似乎不太重要。如果下午有菊科花，通才和专业传粉者会访问它们，这总体上减少了上午和下午之间的链接周转率。菊科植物下午的可用性对网络中其他植物的影响尚无定论：传粉媒介与菊科植物之间的转换趋于增加。在聚合（全天）网络的水平上，处理导致菊科植物的优势增加，减少模块化并增加工厂通用性。这些结果强调，网络动态可以通过昼夜或季节性物候学的知识来预测，并且固定的物种时间假设将歪曲预期的动态。