Forest structure and heterogeneity increase diversity and alter the composition of host-parasitoid networks

Rappa, Nolan1 ; Staab, Michael2 ; Ruppert, Laura-Sophia1 ; Frey, Julian1 ; Mello, Marco3 ; Klein, Alexandra-Maria1

Published May 20, 2024 on Dryad. https://doi.org/10.5061/dryad.1ns1rn8zp

Data files

May 20, 2024 version files 326.82 KB

Builder_species_matrix.xlsx

79.40 KB
Environmental_variables.xlsx

28.19 KB
Interaction_cooccurence_matrix.xlsx

71.31 KB
Parasitism.xlsx

42.39 KB
Parasitoid_species_matrix.xlsx

70.93 KB
Plot_geolocations.xlsx

13.79 KB
READ_ME_RappaNJ_etal.txt

3.36 KB
README.md

3.45 KB
Total_builder_parasitism.xlsx

14 KB

Abstract

Antagonistic host-parasitoid interactions can be quantified using bipartite and meta networks, which have the potential to reveal how habitat structural elements relate to this important ecosystem function. Here, we analysed the host-parasitoid interactions of cavity-nesting bees and wasps, as well as their abundance, diversity, and species richness with forest structural elements from 127 forest research plots in southwestern Germany. We found that parasitoid abundance, diversity, and species richness all increase with host abundance, a potential mediator between parasitoids and forest structure. Both parasitoid abundance and diversity increased with stand structural complexity, possibly mediated by the abundance of hosts. Additionally, parasitoid abundance increased with increasing standing deadwood and herb cover. The bipartite networks of host-parasitoid interactions showed higher connectance with increasing standing deadwood, herb cover, and host abundance. Analyses of interactions within the host-parasitoid metanetwork revealed that increasing host abundance and decreasing canopy cover diversify the suites of interactions present at the plot level. These results demonstrate that forest structural elements can improve the stability and resilience of host-parasitoid networks by promoting parasitoids and diversifying interactions in ecological networks.

README: Forest structure and heterogeneity increase diversity and alter the composition of host-parasitoid networks

Builder species matrix

Plot and corner correspond to the plot and corner where the trap nests containing the individuals of each species were collected.
Each species column is labeled with the capitalised first letter of the genus followed by the species name (e.g. A_antilope represents Ancistrocerus antilope). The complete species list with full genera names can be found in the supplement.
Columns with full genera names contain individuals that could not be identified as species. The T_clavicerum_group contains specimens that could be identified as only a grouping of similar species. Analyses included only specimens that could be identified at the species level.

Parasitoid species matrix

Plot and corner correspond to the plot and corner where the trap nests containing the individuals of each species were collected.
Each species column is labeled with the capitalised first letter of the genus followed by the species name (e.g. A_anthrax represents Anthrax anthrax). The complete species list with full genera names can be found in the supplement.
Columns without capitalised genera names followed by species names contain either genus, family or superfamily names with no further identification possible. Several are subdivided using numbers (e.g. Chrysididae1) to indicate a different species, however analyses included only specimens which could be identified to species level.

Parasitism

Plot corresponds to the research plot where the builders cells were parasitized by the parasitoids listed. Parasitized cells represents the number of brood cells of the builder parasitized by the parasitiod in the same rows.

Total builder parasitism

Rows below G_species represent builder species while columns after G_species represent parasitoids. The value in each cell represents the number of brood cells parasitized.

Plot geolocations

Plot ID represents the plot numbers in the study area. The corresponding latitude and longitude values for each plot are listed in the same row.

Environmental variables

plot represents the plot number within the ConFoBi study area. Elevation represents the mean elevation value (m) at plot level. ENL_transect and SSCI_transect represent the mean of three values taken along the NW-CENTER-SE transect of each plot. forest-cover_1km represents the proportion (%) of forested area in the 1km sorrounding plot centers. herb_cover represents the proportion (%) of area covered by herbs. prop deciduous represents the proportion (%) of trees at plot level which are deciduous species. mean_canopy_cover represents the mean canopy cover (%) calculated from the NW and SE corners of each plot. stnd_dw_DBHsum_ds123 represents the cumulative DBH (cm) of standing deadwood of decay stages 1, 2 and 3. lying_dw_DBHsum_ds123 represents the cumulative DBH (cm) of lyinging deadwood of decay stages 1, 2 and 3.

Interaction cooccurence matrix

The interaction cooccurence matrix is a matrix of interaction cooccurences. The interaction partners are shown as the first letter of the genus followed by the first three letters of the species (e.g. Maca-Melittobia acasta, Tfig-Trypoxylon figulus, interaction=MacaTfig) with parasitoids shown first. This matrix can be generated using the previous dataset "Parasitism".