Skogen Krissa A, Jogesh Tania, Hilpman Evan T, Todd Sadie L, Rhodes Matthew K, Still Shannon M, Fant Jeremie B
Chicago Botanic Garden 1000 Lake Cook Road, Glencoe, Illinois 60022 USA
Chicago Botanic Garden 1000 Lake Cook Road, Glencoe, Illinois 60022 USA.
Am J Bot. 2016 Nov;103(11):1950-1963. doi: 10.3732/ajb.1600302. Epub 2016 Nov 1.
Land-use change is cited as a primary driver of global biodiversity loss, with myriad consequences for species, populations, and ecosystems. However, few studies have examined its impact on species interactions, particularly pollination. Furthermore, when the effects of land-use change on pollination have been studied, the focus has largely been on species pollinated by diurnal pollinators, namely, bees and butterflies. Here, we focus on Oenothera harringtonii, a night-flowering, disturbance-adapted species that has experienced a range-wide gradient of land-use change. We tested the hypothesis that the negative impacts of land-use change are mitigated by long-distance pollination.
Our study included both temporal (4 yr) and spatial (19 populations range-wide, and 1, 2, and 5 km from the population center) data, providing a comprehensive understanding of the role of land-use change on pollination biology and reproduction.
We first confirmed that O. harringtonii is self-incompatible and reliant on pollinators for reproduction. We then showed that hawkmoths (primarily Hyles lineata) are highly reliable and effective pollinators in both space and time. Unlike other studies, we did not detect an effect of population size, increased isolation, or a reduction in suitable habitat in areas with evidence of land-use change on pollination (visitation, pollen removal and deposition). Furthermore, the proportion of suitable habitat and other fragmentation metrics examined were not associated with population size or density in this plant species.
We conclude that nocturnal pollination of Oenothera harringtonii via hawkmoths is robust to the negative impacts of land-use change.
土地利用变化被认为是全球生物多样性丧失的主要驱动因素，对物种、种群和生态系统产生了无数影响。然而，很少有研究考察其对物种相互作用的影响，尤其是授粉作用。此外，在研究土地利用变化对授粉的影响时，重点主要放在由日间传粉者（即蜜蜂和蝴蝶）授粉的物种上。在这里，我们关注的是哈灵顿月见草（Oenothera harringtonii），这是一种夜间开花、适应干扰的物种，经历了广泛的土地利用变化梯度。我们检验了这样一个假设，即土地利用变化的负面影响会通过远距离授粉得到缓解。
我们的研究包括时间（4年）和空间（涵盖19个种群，以及距离种群中心1公里、2公里和5公里处）数据，从而全面了解土地利用变化在授粉生物学和繁殖中的作用。
我们首先证实哈灵顿月见草自交不亲和，依赖传粉者进行繁殖。然后我们表明，天蛾（主要是细纹透翅蛾Hyles lineata）在空间和时间上都是高度可靠且有效的传粉者。与其他研究不同，我们没有检测到在有土地利用变化迹象的地区，种群大小、隔离增加或适宜栖息地减少对授粉（访花、花粉去除和沉积）有影响。此外，所研究的适宜栖息地比例和其他破碎化指标与该植物物种的种群大小或密度无关。
我们得出结论，哈灵顿月见草通过天蛾进行的夜间授粉对土地利用变化的负面影响具有抗性。
