Farmland pollinators are influenced by landscape structure, including mean field size, floral resources, the amount of semi-natural habitats and crop type, but their relative importance and interactions for bumblebee colony performance are not well known. In our study, we focused on the concurrent role of crop type (oilseed rape vs. cereal), proximity to semi-natural habitats (close vs. far) and landscapes with small (average 2 ha) and large fields (average 17 ha) on experimentally exposed bumblebee colony fitness parameters; we also carried out a botanical survey and analysed pollen collected by the bumblebees. We conducted a homing experiment, with workers translocated 0.1–1 km from the colony, and measured the homing speed. We found a significantly higher colony traffic rate next to mass-flowering oilseed rape fields and close to semi-natural habitats. According to our structural equation model, higher traffic rates boosted colony growth rates, which in turn supported higher queen brood cell numbers. In the homing experiment, the relocated bumblebees returned to their home colony faster when it was located close to semi-natural habitats and when the flowering plant species richness was high. The homing speed was lower when semi-natural habitats were distant and flowering plant species richness was high, possibly due to fewer visual cues. Semi-natural habitats were more important for pollinators in large-scale than in small-scale agriculture. In small-scale landscapes, bumblebees returned more quickly when flowering plant species richness was low, presumably because the small-scale landscape structure (higher edge density) allowed for easier navigation by landscape visual cues. The abundance of flowering plants did not affect homing speed, presumably underlining the predominant role of orientation in small-field landscapes. Synthesis and applications: Mass-flowering crops and nearby semi-natural habitats enhance colony growth and queen production, emphasising the important role of abundant and diversified flower resources as well as neighbouring semi-natural habitats. Further, landscapes shaped by small-scale farming are crucial for sustaining and enhancing pollinator populations. Our results underscore the need to restore and maintain semi-natural habitats and to enhance floral resources. These efforts are especially effective in small-scale agricultural landscapes, which appear to improve bumblebee orientation and support biodiversity-friendly farming.

Organic rice farming has increasingly gained attention for its potential to enhance biodiversity compared to conventional agricultural methods. In this study, we examined the abundance of plant species groups of conservation interest in rice fields in Hungary, located at the northern periphery of rice cultivation. We compared organically and conventionally managed rice fields to determine their impact on plant biodiversity. Our results indicated that organic fields generally support a greater abundance of non-harmful macrophytes, charophytes, and red-listed species. However, these differences were less pronounced in fields considered less ecologically valuable, irrespective of management types. Our analysis revealed that water conductivity had a more significant impact than farming type. Lower conductivity correlated with weed communities of higher conservation values, particularly in organically managed fields. This effect was significant compared with conventional fields but was only evident in areas with relatively low conductivity, likely reflecting low nutrient levels in the water. These findings suggest that to maximize biodiversity benefits, organic agriculture should be practiced alongside the judicious use of low amounts of organic manure or nutrients. Such practices could enhance species-rich macrophyte communities, contributing to the preservation of the unique biodiversity found in this historic rice cultivation region.