An on‐farm approach to investigate the impact of diversified crop rotations on weed species richness and composition in winter wheat

Abstract

Weed species diversity may benefit from organic farming due to enhanced temporal diversification of crop species in a rotation and omission of herbicide applications. However, in intensively managed conventional systems, little evidence exists as to what extent diversified crop rotations contribute to higher weed species richness. Using an on-farm approach, the effect of crop rotation (organic, conventional diverse (CD) and conventional simple (CS) crop rotations) and weed control (with vs. without) on weed species richness, cover, community composition and crop biomass, was analysed in 24 winter wheat fields. Weed species with beneficial functions for invertebrates and birds were analysed separately. Weed species richness was higher in the organic crop rotation, but did not differ between CD and CS crop rotations. Weed control treatment reduced species richness in both conventional rotations, but not in the organic one. Redundancy analyses revealed that crop rotation intensity accounted for the largest part of the explained variation in weed species composition. Results from the study indicate that the maintenance of weed species richness and conservation of species with important ecological functions requires not only temporal diversification of crop species in the rotation, but also an adjustment of weed control strategies.

Assessing the environmental performance of English arable and livestock holdings using data from the Farm Accountancy Data Network (FADN)

“…Consequently, large livestock holdings might be expected to have a greater proportion of fields with reduced management intensities. In the current study, large holdings provided greater proportions of low input habitats, which increased values of land use diversity (Shannon), important for biodiversity (Ulber et al, 2009). The greater energy consumption and water use per ha UAA associated with small livestock farms (compared with large farms) also reduced environmental performance.…”

Effects of the Tillage Technology and the Forecrop on Weeds in Stands of Winter Wheat

“…methods of tillage and/or crop rotation) determine signifi cantly the composition of weed population and numbers of weeds on fi elds (Ulber et al, 2009). Many authors mentioned a general rule according to which the deeper and more frequent the processing of topsoil, the lower the degree of infestation and also the more limited magnitude of the soil seedbank (Cardina et al, 2002;Moonen & Bárberi, 2004;Légère et al, 2011).…”

“…tillage and crop rotation) very o en determine both the diversity and intensity of weed infestation (Ulber et al, 2009). Recent studies performed by Gonzalez-Andujar et al (2011) demonstrated the importance of longterm experiments studying eff ects of growing methods on the abundance and composition of weed populations.…”

Weed species diversity in organic and integrated farming systems

“…In some approaches, integrated farming is considered as part of the conventional system [32]. Due to differences in classification as well as in the scale and protocol of experiments, weed species diversity in fields under the integrated cropping system cannot be unambiguously placed in between the biodiversity values determined in conventional and organic systems [33,34]. According to some authors [30], weed species diversity in integrated and conventional systems can be considered comparable, while other studies [35] point to higher similarity between integrated and organic systems in this respect.…”