How rare arable weeds are descriptors of low farming intensification?

International audience; Recent emphasis has been placed on the rapid destruction of the planet’s biodiversity in allhabitats. Rare arable weeds, also known as segetal plants, are threatened species, mostly indecline due to intensive farming systems. However, the presence of these species is intrinsicallylinked to agroecosystems. Their survival is apparently related to low-input agronomic practices.Could these weeds therefore be good descriptors of low agricultural intensification and be goodindicators of high environmental field value? We propose to examine the relationships between thefarming systems and weed flora sampling in the same fields.