Landscape composition and heterogeneity, at different spatial scales, may have a fundamental role in shaping the natural enemy assemblages within crops and other greenspaces, and their efficiency in biological control. The majority of natural enemies must colonize fields from other crops or natural and semi-natural habitats. Nevertheless, with the intensification of agriculture, several of these habitats are lost, and with that also a reduction of natural enemies may occur, especially natives that usually depend more on less disturbed habitats. Therefore, maintaining the heterogeneity of the agricultural landscape can have a double role: 1) increase conservation biological control by increasing the abundance and diversity of natural enemies, regardless of their origin, and 2) conserve native species of natural enemies in productive ecosystems. Coccinellids are very important biocontrol agents of aphids and other pests and there is strong evidence that they move across the landscape and respond to its composition and configuration. In Central Chile, one of the biodiversity hotspots, coccinellid are very diverse, including several native and a few, but dominant, exotic species. In this talk, we will discuss how the abundance, composition and function of native and exotic coccinellids are affected by landscape composition and configuration. First, we will show how the abundance and movement of coccinellids toward alfalfa crops depend on edge vegetation. Second, we will analyze how native and exotic species differentially use cover types depending on their disturbance. Third, we will evidence how landscape composition and heterogeneity affect the abundance and diversity of native and exotic coccinellids within alfalfa fields and their biological control service, and finally, we will show in a rural-urban gradient how coccinellid assemblages are filtered by landscape characteristics. Our results highlight the importance of maintaining landscape heterogeneity at different spatial scales in order to conserve the composition and functionality of natural enemies in agroecosystems.
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