Farmed landscapes and field margins influence on arthropod assemblages and ecological functions

MOLINA, GONZALO A R; POGGIO, SANTIAGO L; GHERSA, CLAUDIO M

Encyclopedia of Pest Management

Taylor & Francis

Año: 2014; p. 1 - 5

This entry reviews how landscape heterogeneity and field margins may interact and influence the ways in which arthropod assemblages are established in farmland mosaics and provide for ecosystem services. Crop fields are ephemeral habitats due to cropping management, which establish an important role in organism flows between non-cropped habitats and crops. Cross-habitat foraging by herbivores and predators may link the dynamics of contrasting habitats. An emerging property in agro-ecosystems results from resources within a habitat that subsidize shared consumers enhancing their impact on resources in neighboring habitats. Non-cropped habitats, such as field margins, fencerows, and meadows, harbor more stable and diverse communities than (annual) crops. These habitats provide many resources for parasitoids and predatory arthropods, such as permanent vegetation cover suitable for overwintering, refuges from disturbance, as well as alternative prey resources. Natural enemies significantly contributing to pest control should have a rapid numerical response to herbivore density. For this to happen, natural enemies should breed within crops by either recruiting them easily from nearby non-cropped habitats or colonizing them from a larger distance.