Gardarin Antoine, Valantin-Morison Muriel
UMR Agronomie, INRAE, AgroParisTech Université Paris-Saclay Thiverval-Grignon France.
Ecol Evol. 2022 Oct 18;12(10):e9435. doi: 10.1002/ece3.9435. eCollection 2022 Oct.
In agroecosystems, species-rich habitats, such as linear field margins and flower strips, are beneficial to the overall biodiversity and contribute to pest control. Their effects are thought to be mediated by plant species composition and diversity. However, the management of plant communities with targeted levels of functional diversity has been little investigated. In an open field landscape, we compared the effects of the sown species richness (9, 14, and 29 species) and functional diversity (high vs. low) of eight different seed mixtures, sown in flower strips, on the 4-year temporal dynamics of their functional diversity. There was a good agreement between the expected and realized species richness and functional diversity at the start of the experiment. All plant assemblages progressively lost species over time, but this decline was lower for assemblages sown with a high initial functional diversity, in which species evenness was maintained at higher levels. Species-rich assemblages had a higher degree of functional redundancy, and their functional diversity remained higher over time than less rich assemblages. A possible explanation for this is that functional redundancy would have enabled the compensation for the loss of species by functionally equivalent species. The realized functional diversity of the sown species also limited the establishment of spontaneous species, perhaps due to a higher degree of niche occupancy. This study provides useful insight into the creation of functionally diversified plant communities. A high level of initial species and functional diversity is required to guarantee a greater temporal persistence of the communities.
在农业生态系统中，物种丰富的栖息地，如线状田边和花卉带，对整体生物多样性有益，并有助于害虫控制。人们认为它们的作用是由植物物种组成和多样性介导的。然而，针对功能多样性水平进行植物群落管理的研究却很少。在一个开阔的田野景观中，我们比较了播种在花卉带中的八种不同种子混合物的播种物种丰富度（9种、14种和29种）和功能多样性（高与低）对其功能多样性4年时间动态的影响。在实验开始时，预期的和实际的物种丰富度及功能多样性之间有很好的一致性。所有植物组合都随着时间的推移逐渐失去物种，但对于初始功能多样性高的组合，这种下降幅度较小，其中物种均匀度保持在较高水平。物种丰富的组合具有更高程度的功能冗余，并且随着时间的推移，它们的功能多样性比物种较少的组合更高。对此的一种可能解释是，功能冗余能够使功能等效的物种对物种损失进行补偿。播种物种的实际功能多样性也限制了自发物种的建立，这可能是由于生态位占据程度较高。这项研究为创建功能多样化的植物群落提供了有益的见解。需要高水平的初始物种和功能多样性来保证群落具有更大的时间持久性。
