Annual Wildflower Strips as a Tool for Enhancing Functional Biodiversity in Rye Fields in an Organic Cultivation System

Abstract

Ecological intensification of agriculture (e.g., with the use of wildflower strips) is being currently discussed as a mean for gaining high yields, preserving high biodiversity of farmland. The aim of this study was to assess the efficiency of annual wildflower strips (WFSs) established in rye field (RF) in (1) increasing species richness and abundance in terms of beneficial arthropod groups (carabids, ground spiders, plant spiders, butterflies, insect pollinators and plant-dwelling insect predators), (2) decreasing the abundance of insect pests, (3) decreasing damages of the crop, and (4) increasing the yield. The field survey was carried out in 2019, in two WFSs and in the adjacent crop field at the distances of 3, 9, 21 and 45 m. The study was not skewed by pesticide use as it was carried out on an organic farm. Mean “site” species numbers (α-diversity) and the abundance of most groups were found to be significantly higher in WFSs than in RF. A negative relationship was found in most groups between distance from WFSs and species numbers and abundance. The mean total abundance of all observed pest insects was positively related to distance from WFSs and increased by 83% at distances between 3 and 45 m from WFSs. There was a negative exponential relationship between aphid abundance and total predator abundance, which suggests a mechanism reducing aphid abundance resulting from high levels of predator abundance in the nearby WFSs. The study shows that annual WFSs can be an efficient measure for enhancing cropland biodiversity and should be taken into account in agri-environmental schemes in the Common Agricultural Policy after 2020.

Flower Strips and Their Ecological Multifunctionality in Agricultural Fields

“…Bumblebees were virtually absent from the typical greenways sown with grasses. In research by Kujawa et al [22], 14 butterfly species of five families were observed in flower strips, and the most abundant species was Vanessa cardui L. (54%). As shown by our one-year observations (unpublished data from western Poland, 2022), the most frequently occurring butterfly in a flower strip was Aglais io L., which mostly favoured the inflorescence of Trifolium pratense (L.).…”

“…Unfortunately, due to the disappearance of refuges in fields, carabids are facing extinction [2,26]. Kujawa et al [22] reported that as many as 46 carabid species were observed in flower strips. The most abundant species was Harpalus rufipes (hemizoophage, feeding on both plants and animals), which constituted 45.8% of the particular beetle numbers, and the most abundant of the 47 ground spider species was Pardosa agrestis (24% of all individuals).…”

“…The EU strategy for biodiversity is thus a key element of the European Green Deal. It should help to recover biodiversity in Europe by 2030, and its activities include restoring degraded ecosystems by limiting the use of pesticides [21,22], implementing environmental eco-schemes and supporting green, carbon and generally sustainable farming.…”

In‐field cover crop strips support carabid communities and shape the ecological trait repartition in maize fields

“…Such spillover and the effect of AEI in general on the adjacent crops have been mainly investigated through the measurement of the abundance and richness of beneficial arthropods. Some studies showed such spillover effect (Gayer et al, 2019;Woodcock et al, 2016), but in others, this could not be clearly observed (Kujawa et al, 2020;Triquet et al, 2022). Indeed, little is known about this process, and particularly about the impact of AEI on the composition and the ecological trait distribution of arthropod communities in adjacent fields at different distances from the AEI (Boetzl et al, 2018;Gallé et al, 2020;Gayer et al, 2019;Pecheur et al, 2020).…”

“…Generally, placed at the edge of cropped fields, they have a particular interest for multiple ecosystem services, for example, water regulation and purification, and prevention of soil erosion. Many studies have shown the attractiveness of vegetation strips for a large range of beneficial arthropods (Campbell et al, 2019; Holland et al, 2016; Kujawa et al, 2020; Triquet et al, 2022) including pollinators when they contain flowers (Amy et al, 2018; Haaland et al, 2011). They can offer food resources, shelter (Griffiths et al, 2008; Landis et al, 2005), and overwintering habitat for ground‐dwelling arthropods (Landis et al, 2000; Pywell et al, 2005), and thus are expected to deliver ecosystem services to adjacent cropping (Bianchi et al, 2013).…”