Sustainable Farming for Biodiversity Conservation
The extent and the cultivation of agricultural land play a significant role in biodiversity conservation.
The European Union's Biodiversity Strategy to 2030, linked to the Nature Recovery Plan, gives particular attention to agricultural land since certain agricultural practices are the main cause of biodiversity loss. In order to preserve and restore agrobiodiversity, it is necessary to promote sustainable farming practices, such as extensive farming, organic farming, land use that preserves important landscape elements — like green-yards and buffer strips — and a significant reduction in the use of chemicals. In principle, maintaining the mosaic character of the landscape is key to biodiversity conservation. Besides farmland birds and insects, including pollinators, weed species do not receive enough attention when discussing the impact of agriculture on biodiversity, even though they are a good indicator of the negative effects of current landscape use.
In Hungary, 149 weed species have been identified (Pinke et al. 2011) as being at risk based on a national red list of vascular plants compiled in 2008 (Király et al. 2008). Of these, 64 species (43 %) belong to an endangered category — 11 are critically endangered (CR), 27 are endangered (EN), and 26 are vulnerable (VU). By habitat type, 23 % of species originate from arable land and 13.5 % from ruderal habitats. Some examples of arable weeds: Veronica acinifolia is an endangered plant of clay soils and nutrient-poor ploughland; its decline is due to the fact that its habitats are less suitable for arable crops and have been abandoned and then afforested.
The habitats of the critically endangered Turgenia latifolia are difficult to cultivate because of the stony soil, so they have largely been abandoned and used for grazing.
The vulnerable species Glaucinum corniculatum is a weed of loose-soil ploughland and its disappearance is due to the intensification of arable cultivation.
We can find only a few traditionally managed arable fields in Hungary — as well as in the region — which are suitable for preserving arable weeds. In general, the threatened weed species are not protected and occur outside of the protected areas network. The preservation of arable weeds requires special conservation measures. One such is, for example, a special agri-environmental scheme which supports extensive, low-input, chemical-free arable farming or special schemes to focus on the preservation of field margins (green-yards) in selected parcels.
Germany has been working on weed conservation for a longer time so their system is certainly a good example. You can find more information (in German) here: link: https://www.bayerischekulturlandstiftung.de/projekte/lebensfelder/