Abstract
In the past centuries, farmland has undergone a fundamental transformation through changed farming practices, such as the use of agrochemicals and advanced machine processing. Particularly since the 1970s, agriculturally driven land-use change has caused destruction of natural and semi-natural habitats, and as a consequence, severe loss of biodiversity. Hence, identifying landscape patterns and habitats that enhance species richness, and detecting species and traits that are most vulnerable to intensive land-use are prerequisites for conservation. To evaluate the effects of agricultural land-use and landscape composition on wild bees, we investigated 340 cross-transects in 34 test areas in the main agricultural regions of Austria within the framework of the biodiversity monitoring program BINATS. Using multivariate models (GLM, DCA), wild bees and potential explanatory parameters (e.g. Shannon landscape diversity index, plant diversity, flower cover) were documented, and their interrelationships analyzed. We found strong negative effects of increased agricultural land cover on species richness, abundance and functional richness. Species richness was positively correlated with an increasing area of semi-natural elements (e.g. extensive grassland, hedgerows, fallows) and the number of different habitat types, while wild bee abundance was best explained by the presence of semi-natural habitats and flower cover. Colletidae were significantly associated with the area of semi-natural elements, and were especially sensitive to agricultural intensification. Many species from communities that are present in complex landscapes disappeared in intensively managed farmland, and the majority of species decreased in response to simplified landscapes. A few species, however, even benefited. Our results emphasize the importance of diverse semi-natural elements and high regional flower cover within farmland for maintaining and enhancing species richness and abundance, and for promoting a positive spillover effect of pollinators to the surrounding agricultural landscape. Especially members of the family Colletidae, with a high proportion of specialized species, will benefit from diverse semi-natural habitat types. Given the unique importance of wild bees as pollinators of wildflowers and crops, it is crucial to improve and expand agri-environmental schemes to combat ongoing biodiversity loss in farmland.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.