Structural field margin characteristics affect the functional traits of herbaceous vegetation

Abstract

Background Field margins are ecologically important to an agroecosystem as they are a source of biodiversity. They can be composed of a diverse flora which may offer resources to a wide range of insects and birds. The vegetation composition of field margins is determined by soil characteristics, management, and landscape structures. However, little is known about the effect of individual field margin components such as ditches, grass strips, shrubs and trees, and the overall margin’s complexity, on the vegetation composition and its functional effect and response traits. Methods This paper reports on the effects of field margin component typology (ditches, grass strips, shrubs, trees, and vehicle tracks) and complexity (the number of components), on the herbaceous vegetation of field margins. Forty field margins were sampled in 2016 in a 200 ha. organic mixed arable livestock farm. Results The factor which was identified as having the most effect on vegetation composition was adjacent land-use type, which reflected the margins’ management regime. However, field margin components were found to affect vegetation response and effect traits. Tree components had less grassweeds than vehicle tracks while more complex field margins also had less grassweeds than simple field margins near cropped fields, most likely due to the lower availability in light and less disturbance from vehicles. Simple grassy margins produced a high proportion of hymenoptera flowers. Discussion These results highlight the importance of field margin components in maintaining a high diversity of vegetation typologies differing in effect traits that are relevant for the provisioning of ecosystem services, such as supporting pollen and nectar requirements of beneficial insects, as well as their importance in determining the presence of weed species that could potentially invade the cropped fields.

Impact of new management practices on arable and field margin plant communities in sunflower, with an emphasis on the abundance of Ambrosia artemisiifolia (Asteraceae)

“…In field margins, the type of land use adjacent to the field margin had a stronger influence than landscape diversity at a larger scale. The presence of ditches, hedges, small woods or grasslands close to the field margin was found to be a clear and strong factor associated with greater species diversity (Blaix and Moonen, 2020), together with less weedy species and more species specific to field margins (Cirujeda et al, 2019; Fried et al, 2018). Neighbouring infrastructures also influenced the management of the field margins cut more often near farm tracks than near paved roads.…”

Conséquences de l’utilisation de variétés de tournesol tolérantes aux herbicides sur la flore des agrosystèmes

“…L'IFT herbicide et les modes de gestion (BIO, CVT, VrTH) n'ont pas d'influence sur la diversité de la flore de la bordure contrairement à ce qui a été mis en évidence avec le même protocole à une plus grande échelle (France) et sur une plus grande diversité de cultures (Fried et al, 2019). Dans le réseau de parcelle ENI-VrTH, la végétation de la bordure est bien plus influencée par la qualité de l'habitat à l'échelle du paysage (indice HVN, Figure 8A) et surtout par l'environnement immédiat de la bordure (Figure 8B) avec une richesse qui augmente avec le nombre d'éléments semi-naturels (haie, fossé, prairie) voisins (Blaix & Moonen, 2020).…”

Not All Field Margins Are Equally Useful: Effects of the Vegetation Structure of Margins on Cereal Aphids and Their Natural Enemies

“…Furthermore, instead of relying simply on vegetation species richness, which is often a poor surrogate for the breadth of niche opportunities offered by vegetation, the use of functional traits allows us to infer the resources provided by plants. From the many aspects relevant for insects, the life form integrates different characters of plant structure and functioning since it is a good indicator of both the height and the structure of vegetation, and whether or not the margin is permanently vegetated throughout the year [ 15 , 16 ]. Therefore, this information can help determine the value of margin vegetation for pest species, and for the conservation and promotion of biological control agents [ 7 , 8 ], since each group of organisms has its own behavior, life-cycle requirements and degrees of mobility that depend on traits such as body size and trophic level [ 17 , 18 ].…”