亚高山草甸植物种间花粉传播网络相对于植物-传粉者互作网络年际间更为稳定

Relative stable interannual variation in plant-plant pollen transfer rather than the plant-pollinator network of a subalpine meadow

现有研究表明植物-传粉者互作网络结构有较高的年际动态变化。由于传粉者经常在多种植物之间访问,植物-植物的种间花粉传播也可能有较高的动态变化,这对花部特征演化和群落构建有重要的意义。我们连续3年调查了中国西南部一个亚高山草甸群落的植物-传粉者互作网络和植物-植物种间花粉传播网络的年际动态结构。我们发现两种网络的连接都有较高的年际动态,但是植物落置异种花粉构成的年际变化,低于传粉者访问构成的变化,这说明同一对花粉供体和受体植物之间,在年际间可能由不同的共享传粉者传播异种花粉。植物在种间花粉传播网络中的位置,相对植物-传粉者网络中更为稳定。泛化传粉的植物能够输出更多的异种花粉,在种间花粉传播网络中也更重要。我们评估了植物-传粉者互作网络和种间花粉传播网络的年际动态结构,是整合植物-传粉者与植物-植物互作过程的重要一步。

Previous studies have shown that plant-pollinator mutualistic interactions experience highly interannual variation.Given that pollinators often move across multiple plant species,the plant-plant interactions that take place via heterospecific pollen(HP)transfer may also vary temporally,which could have important implications for floral evolution and community assembly.Here,we evaluated the interannual variation in plant-pollinator networks and plant-plant heterospecific pollen transfer(HPT)networks of a subalpine meadow community in Southwest China for three consecutive years.The interactions largely varied among years for both network types.The composition of donor-species HP deposited on the plants varied less than did the visit composition of the pollinators,suggesting that HP could be transferred from identical donor species to recipient species through different shared pollinators among years.The plant species were at more similar positions in the HPT network than they were in the plant-pollinator network across years.Moreover,the more generalized plant species in the plant-pollinator network tended to export their pollen grains and more strongly influence HPT.We evaluated the relatively stable structure of the HPT network compared with the plant-pollinator network,which represents an important step in the integration of plant-pollinator and plant-plant interactions.