To test the effect of biodiversity on arthropod pattern in the CSP we put 10 yellow sticky traps in each CSP. 5 traps are at 2 m from the ground and 5 traps were set up within the tree crown. The arthropod were then counted on each trap, separating them into morphospecies. They are as well classified by their order and by their feeding guild. Data collection took place from the end of June to mid-August 2010. Ten standard yellow sticky traps used for pest control in gardens (9 x 11 cm sticky area, double face, MIOPLANT “Leimfallen”, Switzerland) were implemented in each study plot. The traps were accessible to arthropods between 140 and 215 hours (same exposure duration within a plot), which corresponds to 6-9 days. This irregular exposure time was a consequence of logistic difficulties to visit the plots. In order to sample two distinct areas of the plot, the 10 traps were divided into two groups. Five traps were fixed over bamboo sticks (hereafter called “bamboo traps”) at 2 m height to cover the low understory of the plot. One bamboo trap was positioned at the center of the plot, the four others in the center of the four corner subplots. The sticky sides of the bamboo traps were oriented East-West. The five other traps were hung in the crown of five different tree individuals (hereafter called the “tree traps”) chosen because they were representative of the tree species composition of the plot. Those traps covered the higher part of the canopy and were set up to be within the tree crowns whenever possible. Their location height ranged from 3 m to 18 m, the tree canopy top heights ranged from 7 m to 30 m. Small ballasts were fixed at one extremity of the traps. The traps were then hung with fishing wire (diameter of 0.35 mm) passing over the branches situated in the upper part of the canopy. In each plot, the five tree species having the largest numbers of individuals with a stem >10 cm diameter at breast height (DBH) were selected. If some species had the same number of individuals, the species with the greatest summed area at breast height were chosen. If less than five tree species had individuals with a DBH above 10 cm, two traps were hung to two different individuals of the same species. Within tree species, individuals were chosen at random. After collection, the traps were protected by a plastic film and stored in a freezer until further processing. Yellow sticky traps, as colored interception traps, necessarily induce a bias in the kind and in the amount of arthropod sampled: flying adults are much more likely to be trapped than sessile or juvenile individuals (Missa et al. 2008). Additionally, the color itself induces a bias toward the arthropod species that are specifically attracted to yellow. But according to Hoback et al, (1999), trap color does not affect the number of arthropod species captured. Arthropod abundances are trap-type dependent and are therefore unreliable for total arthropod estimation (Johnson 1950). However, the goal of our study is to compare sites: since the same sampling bias is present in each site, the comparison remains meaningful. Missa et al. (2008) showed that the type of habitat had much more influence over the arthropod sampled than did the catching method. The traps were defrosted and the plastic film was removed. Arthropod identification was carried out on the traps themselves. Arthropod identification to the species level is extremely time-consuming. Given that the aim of this study was not taxonomical, the arthropods were classified by order, part of them further by families and then, based on external morphological characteristics, by morphospecies. Larvae were considered as separate morphospecies because their diet can be very different form their respective adult form (e.g. Lepidoptera, from folivore to nectarivore). In total, 37 morphospecies were recognized as larvae and 561 as adults. Based on the advanced taxonomical knowledge of local experts (Dr. Jiayong Zhang, Zhejiang Normal University, Jinhua) and the inspection of the arthropod mouthparts, each morphospecies was classified into one of the following feeding guilds: folivores, sap-suckers, predators (including parasitoids), detritivores, pollinators (as adult butterflies which do not damage leaves anymore) and miscellaneous (herbivore arthropods that cannot be classified in any of the previous guild, mostly thrips and different fly species).

See methods

Sampling took place in the CSPs of the Guitianshan National Natural Nature Reserve (GNNR) in the Zhejiang Province of southeastern China. For more detailed location information see Datagroup "BEF Research Plot Name". Here, only Data from the CSPs 1-15 are presented.

see range

all the arthropods trapped

none

total abundances, species compositions, species richness. All this total and by feeding guilds