The conservation of natural areas has been proposed as an important management tool to mitigate the negative consequences of agricultural intensification on ecosystem services crucial for food production. Although many studies have focused on how the presence of natural areas in the landscape affect arthropod communities that deliver important ecosystem services or disservices very little is known about how this actually translates into crop yield. Here, we will present three case studies exploring how landscape composition influences crop yield mediated by effects on arthropod communities. We will present data on potato, strawberry and cabbage systems to answer the following questions: 1) does maintaining natural areas increase yield in cropping systems? and 2) does the whole community or just individual species determine the mayor effect of landscape composition on yield?
Results/Conclusions
In all cases we found that landscape composition had an effect on arthropods that influenced crop yield. For strawberries, the abundance of wild pollinators was the most important factor followed by herbivores in determining yield. Wild pollinators where negatively affected by landscape simplification, suggesting that natural areas are needed to maintain a high productivity of this crop. In the case of potato and cabbage the abundance of a single herbivore species seemed to be mediating the main effects of landscape composition on yield. However, only in one case the presence of natural areas was beneficial to increase yield while in the other case it was related with greater herbivory and reduced yield. Our three case studies provide more evidence that the conservation of natural areas could increase yields mediated by changes in the arthropod community, further advancing our knowledge of arthropod mediated landscape effects on yields. However, our data also show that this effect is context dependent and cannot be generalized. If we want to provide convincing evidence on the importance of natural habitats for food production, more studies are needed that investigate these effects. We also need to start incorporating effects on other ecosystem services such as climate change mitigation that could offset losses in crop yields in the near future.