Detecting patterns of species co-occurrence is among the main tasks of plant community ecology. Arable plant communities are important elements of agroecosystems, because they support plant and animal biodiversity and provide ecosystem services. These plant communities are shaped by both agricultural and environmental drivers. The pressure of intensive agriculture worldwide has caused the decline of many characteristic arable species and communities. Italy is the European country where arable plant biodiversity is the best preserved. In this study, we assessed the patterns of co-occurrence of rare and threatened arable plants in 106 plots of winter arable vegetation located from Piedmont to Calabria, in the mainland part of the country. For this purpose, we based our investigation on the analysis of a recently acquired dataset and on the European list of rare and threatened arable plants. We highlight how different species of conservation interest tend to occur in the same community. On the other hand, generalist and more competitive taxa show similar patterns of co-occurrence. We suggest that single species of conservation value could be suitable indicators of a well-preserved community. On the other hand, to be effective, conservation strategies should target the whole community, rather than single species.

中文翻译：

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意大利冬季可种植植物群落中稀有和受威胁物种同时发生的模式

物种共生模式的检测是植物群落生态学的主要任务之一。耕地植物群落是农业生态系统的重要组成部分，因为它们支持动植物的生物多样性并提供生态系统服务。这些植物群落受到农业和环境驱动因素的影响。全世界集约化农业的压力导致许多特色耕种和社区的减少。意大利是可保存植物生物多样性得到最佳保存的欧洲国家。在这项研究中，我们评估了该国中部地区从皮埃蒙特到卡拉布里亚的106处冬季耕地植被中稀有和受威胁的耕地植物共存的模式。以此目的，我们的调查基于对最近获取的数据集的分析以及欧洲稀有和受威胁耕地植物的清单。我们着重说明在同一社区中倾向于发生不同物种的保护兴趣的趋势。另一方面，通才和更具竞争力的分类单元显示出类似的共现模式。我们建议，具有保护价值的单一物种可能是一个保存完好的社区的合适指标。另一方面，为了有效，保护策略应针对整个社区，而不是单一物种。我们建议，具有保护价值的单一物种可能是一个保存完好的社区的合适指标。另一方面，为有效起见，保护策略应针对整个社区，而不是单一物种。我们建议，具有保护价值的单一物种可能是一个保存完好的社区的合适指标。另一方面，为有效起见，保护策略应针对整个社区，而不是单一物种。