Department of Ecology, Faculty of Biology, Philipps-University Marburg, Marburg, Germany.
Biodiversity and Conservation Unit, Department Biology, Geology, Physics and Inorganic Chemistry, ESCET, URJC, Móstoles, Madrid, Spain.
Plant Biol (Stuttg). 2021 Jan;23(1):184-192. doi: 10.1111/plb.13183. Epub 2020 Nov 4.
The effects of habitat fragmentation on plant populations are complex, as it might disrupt many ecological processes, including plant reproduction and plant-animal interactions. Gypsum specialist plants may be resilient to fragmentation due to their evolutionary history in fragmented landscapes, but the effects on non-specialist plants occurring in gypsum are unknown. We conducted a study focusing on different aspects of the reproductive cycle of Astragalus incanus subsp. incanus, a plant facultatively linked to gypsum soils. We focused on plant fecundity and pre-dispersal predation, obtained from field observations, and offspring performance, assessed in a common garden. Beyond fragment size and connectivity, we also considered habitat quality, population size and density and plant size as predictors. Fragment size and connectivity had no effect on plant fecundity, but jointly determined fruit predation, while fragment size was positively related to offspring growth. Population density, rather than population size, had a positive effect on predation but negatively affected plant fecundity and offspring performance. Habitat quality reduced both plant fecundity and predation incidence. In this non-specialist species, habitat fragmentation, population features and habitat quality affect different facets of plant performance. Predation was the only process clearly affected by fragmentation variables, fecundity mainly depended on population features and offspring performance and was better explained by mother plant identity. Our results show the need to consider habitat and population features together with fragment size and connectivity in order to assess the effects of fragmentation. Importantly, these effects can involve different aspects of plant reproduction, including plant-animal interactions.
生境破碎化对植物种群的影响较为复杂，因为它可能会破坏许多生态过程，包括植物繁殖和植物-动物相互作用。由于在破碎化的景观中进化的历史，石膏专性植物可能对破碎化具有较强的适应能力，但石膏中非专性植物的影响尚不清楚。我们进行了一项研究，重点关注了偶见石膏土壤的黄花棘豆亚种黄花棘豆繁殖周期的不同方面。我们关注了植物的繁殖力和预分散捕食，这些数据是通过野外观察获得的，而后代的表现则是在一个普通花园中评估的。除了片段大小和连通性外，我们还考虑了栖息地质量、种群大小和密度以及植物大小作为预测因子。片段大小和连通性对植物繁殖力没有影响，但共同决定了果实捕食，而片段大小与后代生长呈正相关。种群密度，而不是种群大小，对捕食有积极影响，但对植物繁殖力和后代表现有负面影响。栖息地质量降低了植物繁殖力和捕食发生率。在这个非专性物种中，生境破碎化、种群特征和栖息地质量影响着植物性能的不同方面。捕食是唯一明显受破碎化变量影响的过程，繁殖力主要取决于种群特征，后代的表现则更好地解释了母株的身份。我们的研究结果表明，需要综合考虑栖息地和种群特征，以及片段大小和连通性，以评估破碎化的影响。重要的是，这些影响可能涉及植物繁殖的不同方面，包括植物-动物相互作用。
