Affordable Access

deepdyve-link
Publisher Website

Spiders in rice-paddy ecosystems shift from aquatic to terrestrial prey and use carbon pools of different origin.

Authors
  • Radermacher, Nico1
  • Hartke, Tamara R2
  • Villareal, Sylvia3
  • Scheu, Stefan2, 4
  • 1 J. F. Blumenbach Institute of Zoology and Anthropology, University of Göttingen, Göttingen, Germany. [email protected] , (Germany)
  • 2 J. F. Blumenbach Institute of Zoology and Anthropology, University of Göttingen, Göttingen, Germany. , (Germany)
  • 3 Crop and Environmental Sciences Division, International Rice Research Institute (IRRI), Los Baños, Philippines. , (Philippines)
  • 4 Centre of Biodiversity and Sustainable Land Use, University of Göttingen, Göttingen, Germany. , (Germany)
Type
Published Article
Journal
Oecologia
Publisher
Springer-Verlag
Publication Date
Mar 01, 2020
Volume
192
Issue
3
Pages
801–812
Identifiers
DOI: 10.1007/s00442-020-04601-3
PMID: 32002648
Source
Medline
Keywords
Language
English
License
Unknown

Abstract

Spiders are important bio-control agents of rice insect pests such as plant- and leafhoppers. To investigate temporal changes in spider prey and variations in prey due to landscape structure around rice fields, carbon and nitrogen stable isotopes of rice field arthropods were analysed over three consecutive sampling dates during the rice cropping season. Initial isotope composition of gnats and midges emerging from submersed rice fields indicates a larval algae diet, while later values suggest a switch to rice-derived carbon. Initial δ13C values of plant- and leafhoppers were higher in fields of rice-heterogeneous landscapes, indicating migration from source populations feeding on C4 grasses into rice fields; later, their δ13C values approached those of rice. Isotope values of web-building and cursorial spiders in the earliest samples indicate aquatic gnat and midge prey. The later shift toward terrestrial herbivore prey was more pronounced for small than for larger species and in rice paddies near permanent vegetation, indicating use of prey from the surrounding landscape. The results suggest that rice field spiders are supported by three different carbon pools: (1) aquatic carbon originating from algae and (2) legacy carbon from previous growing cycles, both incorporated via between-season predation on gnats and midges, and (3) carbon from the current rice season incorporated via herbivore prey. In conclusion, fostering aquatic midge and gnat larvae, e.g. via mulching, and integrating rice fields into rice-heterogeneous landscapes likely strengthens biological control of pest species in rice paddies by supporting high populations of spiders between cropping seasons.

Report this publication

Statistics

Seen <100 times