ISSN:
1432-1939
Keywords:
Predators
;
Pest species
;
Integrated control
;
Augmentation
;
Succession
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Summary A 5-year-field experiment was performed in a meadow to test the effect of strip-management (small unmown strips alternating with broad mown strips, Fig. 1) on the abundance and composition of arthropods. The species number and density of most predator groups increased from year to year. The succession (parallel to the development of the unmown strips) favoured more specialized species, so that the initial pioneer species become less abundant in consecutive years. In spiders, this succession leads from a dominance of Linyphiidae to a dominance of Lycosidae; the spider biomass increases and probably predator pressure by spiders is augmented. The stability of the predator community (measured as the variance of their frequency in successive years) is higher than that of the phytophagous groups. Under strip-managed conditions the abundance (“activity density”) of most arthropod groups decreases by an average of ca. 12%. The trophic levels, however, are affected to different extents and strong species-specific preferences were found as well. These combined effects lead to constant increase in the ratio of predacious and parasitic to phytophagous insects in the strip-managed area and probably lead also to an increase of the predator pressure facing phytophagous insects. Strip-management is discussed as an important technique among integrated methods for the biological control of pests.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00397876
