||Landscape composition, configuration, and trophic interactions shape arthropod communities in rice agroecosystems
; Seppelt, R.; Horgan, F.G.; Settele, J.; Václavík, T.
|Journal / Serie
||Journal of Applied Ecology
||CLE; BZF; iDiv
||arthropods; biological control; farmland biodiversity; landscape heterogeneity; natural enemies; rice; trophic interactions
- Increasing landscape heterogeneity of agroecosystems can enhance natural enemy populations
and promote biological control. However, little is known about the multiscale effects
of landscape heterogeneity on arthropod communities in rice agroecosystems, especially
in combination with trophic interactions.
- We examined for the first time how landscape heterogeneity, measured by four independent
metrics of landscape composition and configuration at three spatial scales, affected
species abundance and species richness of rice arthropods within four functional groups
and the abundance of the most common species at 28 sites in the Philippines. We additionally
examined the influence of trophic interactions among these functional groups.
- We found that both the compositional and configurational landscape heterogeneity in
combination with trophic interactions determined the structure of rice‐arthropod communities.
Herbivore abundance decreased with increasing landscape diversity. The abundance of
parasitoids and species richness of both parasitoids and predators increased with
the structural connectivity of rice bunds. Fragmentation of the rice landscape had
a clear negative effect on most arthropod groups, except for highly mobile predatory
arthropods. Abundance of common predators and detritivore species decreased with increasing
complexity in the shape of rice patches.
- Trophic interactions, measured as the abundance of prey, outweighed the importance
of landscape heterogeneity for predators. In contrast, parasitoids responded positively
to configurational landscape heterogeneity but were unaffected by prey abundance.
- Synthesis and applications. Our research shows how landscape heterogeneity and trophic interactions have different
effects on different functional groups. While predator abundance was solely driven
by the availability of prey, all other functional groups in the rice‐arthropod community
were significantly affected by the composition and configuration of surrounding landscape
features. Landscape management aiming to improve biodiversity and biological control
in rice agroecosystems should promote a diversity of land uses and habitat types within
100–300 m radii to reduce the presence of pests. Management practices should also
focus on maintaining smaller rice patches and the structural connectivity of rice
bunds to enhance populations of the natural enemies of rice pests. Future research
should focus on the temporal and spatial manipulation of rice fields to maximize the
effects of biological control.
|Dominik, C., Seppelt, R., Horgan, F.G., Settele, J., Václavík, T. (2018):
Landscape composition, configuration, and trophic interactions shape arthropod communities in rice agroecosystems
J. Appl. Ecol. 55 (5), 2461 - 2472