Numerous studies show that landscape simplification reduces abundance and diversity of natural enemies in agroecosystems, but its effect on natural pest control remains poorly quantified. Further, natural enemy impacts on pest populations have usually been estimated for a limited number of taxa and have not considered interactions among predator species. In a quantitative synthesis with data collected from several cropping systems in Europe and North America, we analyzed how the level and within-field spatial stability of natural pest control services was related to the simplification of the surrounding landscape. All studies used aphids as a model species and exclusion cages to measure aphid pest control. Landscape simplification was quantified by the proportion of cultivated land within a 1 km radius around each plot. We found a consistent negative effect of landscape simplification on the level of natural pest control, despite interactions among enemies. Average level of pest control was 46% lower in homogeneous landscapes dominated by cultivated land, as compared with more complex landscapes. Landscape simplification did not affect the amount of positive or negative interactions among ground-dwelling and vegetation-dwelling predators, or the within-field stability of pest control. Our synthesis demonstrates that agricultural intensification through landscape simplification has negative effects on the level of natural pest control with important implications for management to maintain and enhance ecosystem services in agricultural landscapes. Specifically, preserving and restoring semi-natural habitats emerges as a fundamental first step to maintain and enhance pest control services provided by predatory arthropods to agriculture.
Bibliographical noteFunding Information:
Funding was provided by the Swedish Research Council FORMAS to RB, and the European Science Foundation to the AGRIPOPES-project to RB, CT, TT, and WWW. Studies conducted in the UK formed part of the “Rebugging the system” project RES-225-25-0093 funded through the Research Councils UK Rural Economy and Land Use programme. VH acknowledges support of the Polish Ministry of Science and Higher Education . DL and MW acknowledge support from the USDA AFRI Grant # 2007-35302-18272 , the NSF Long-Term Ecological Research Program, and MSU AgBioResearch . TT was supported by DFG and BMBF and WWW was supported by DFG . AR acknowledges support from the FRB (the French Foundation for Research on Biodiversity) and from the cluster of Excellence COTE .
© 2016 Elsevier B.V.
- Arthropods intraguild predation
- Biological control
- Crop protection
- Ecosystem services
- Landscape management
- Spatial stability