Diversified cropping strengthens herbivore regulation by providing seasonal resource continuity to predators

Agricultural practices shape arthropod communities in arable fields, consequently influencing their interactions and the resulting ecosystem services, in particular pest regulation. Predatory arthropods play a pivotal role by preying on herbivores, soil fauna, and on other predators. However, the intricate mechanisms through which different agricultural practices shapes the dietary preferences of predators and regulates herbivore populations remain complex and inadequately understood.
We assessed how fertilisation with organic fertiliser and extending crop rotations with perennial ley affected predation pressure across prey taxa. We mapped predator and prey trophic linkages with molecular analysis of carabid predator gut contents and measured densities and taxonomic richness of predators, herbivores and soil fauna in 19 cereal fields during three samplings across the growing season.
We derived two food web structure metrics: prey vulnerability i.e., the average number of predators feedi..., We assessed regulation of herbivores in two steps. First, we sampled the realised trophic interactions between predators and their prey through metabarcoding of predator gut contents. Second, we characterised predator and prey population densities of soil fauna, herbivore and intraguild prey, sampled with soil extraction, sweep netting and pitfall trapping. With this data, we investigated the vulnerability of soil fauna, herbivores and intraguild prey in time and across diversification treatments, including as predictors predator species richness, population densities and network metrics describing predation redundancy.
We sampled gut contents of carabid predators to identify trophic links between predators and prey below and above ground. To obtain highly resolved data on all consumed prey items in the predators’ diet, gut content samples were analysed through DNA metabarcoding using the primers fwhF2+fwhR2n targeting DNA barcode region in the arthropod mitochondrial cytochrome oxidase..., , # Diversified cropping strengthens herbivore regulation by providing seasonal resource continuity to predators

[https://doi.org/10.5061/dryad.4j0zpc8m6](https://doi.org/10.5061/dryad.4j0zpc8m6)

Molecular data from gut-content PCR-based mitochondrial COI gene DNA analysis from carabid beetles in agricultural habitat.

## Description of the data and file structure

DNA extraction, followed by COI gene PCR, and library preparation. Sequencing on two Illumina NovaSeq6000 SP Flowcell 2x250bp runs.

Data consists of raw FASTQ files with two technical replicates per sample. Retrieved sequence variants (ZOTUs), ZOTU tables, and ZOTU assignations are also included. See the original article for more detailed information.

### File contents and Column names

##### File = 1st\_run\_data.zip, zip-compressed file

This file contains data files from the first sequencing run

*Compressed file = zotus_1strun.fa, fasta-formatted file*

* Each header line begins with character '>', followed by ZOTU ...