Data from: Constructing more informative plant-pollinator networks: visitation and pollen deposition networks in a heathland plant community

Interaction networks are widely used as tools to understand plant–pollinator communities, and to examine potential threats to plant diversity and food security if the ecosystem service provided by pollinating animals declines. However, most networks to date are based on recording visits to flowers, rather than recording clearly defined effective pollination events. Here we provide the first networks that explicitly incorporate measures of pollinator effectiveness (PE) from pollen deposition on stigmas per visit, and pollinator importance (PI) as the product of PE and visit frequency. These more informative networks, here produced for a low diversity heathland habitat, reveal that plant–pollinator interactions are more specialized than shown in most previous studies. At the studied site, the specialization index Embedded Image was lower for the visitation network than the PE network, which was in turn lower than Embedded Image for the PI network. Our study shows that collecting PE data is feasible for community-level studies in low diversity communities and that including information about PE can change the structure of interaction networks. This could have important consequences for our understanding of threats to pollination systems.

植物-传粉者交互网络（Interaction networks）现已被广泛应用于解析植物-传粉者群落结构，并可用于探究当传粉动物所提供的生态系统服务出现衰退时，植物多样性与粮食安全可能面临的潜在威胁。然而，迄今为止的绝大多数此类网络均基于对访花行为的记录，而非对明确界定的有效传粉事件的观测。
在此，我们首次构建了明确纳入两项核心指标的交互网络：一项是基于单次访花在柱头上沉积的花粉量计算的传粉者有效性（Pollinator Effectiveness, PE），另一项是以PE与访花频率的乘积为计算依据的传粉者重要性（Pollinator Importance, PI）。本次针对低多样性灌丛生境构建的这类信息量更为丰富的网络显示，植物-传粉者交互的特化程度要高于绝大多数既往研究中的观测结果。在本研究样地中，访花网络的特化指数（Embedded Image）低于传粉者有效性网络，而传粉者有效性网络的特化指数又低于传粉者重要性网络的特化指数（Embedded Image）。
本研究证实，在低多样性群落中开展群落水平的研究时，收集PE数据具备可行性，且纳入传粉者有效性相关信息可显著改变交互网络的结构。这一发现对我们理解传粉系统所面临的威胁具有重要意义。