Data for: Crop rotation phase has a greater impact on soil biology than crop rotation diversity

In this study, the link between plant diversity and soil biodiversity was investigated in an arable cropping system by comparing the soil biological community structure and biomass in crop rotations with different degrees of diversity: A Simple rotation (2 plant species), a Moderate rotation (4 plant species), and a Diverse rotation (10 plant species). A field experiment was established in 2013 at the Crop Research Unit, University of Reading, Sonning, UK (51°28’50.8”N 0°54’07.3”W). The experiment was laid out in a split-plot randomized complete block design, where a block containing all three rotations (Simple, Moderate, and Diverse) was replicated four times. Each rotation treatment comprised four 12 m x 10 m subplots, representing the four different phases (i.e. years) of the rotation. The design of the experiment relies on a space-for-time substitution, so that each phase in the crop rotation is represented by one of the four subplots in the rotation at any one time.

All 48 subplots of the experiment representing all three diversity levels and all four crop phases were sampled for soil the fauna survey in June 2017. Nematodes were collected to represent microfauna, Collembola and mites to represent mesofauna, and earthworms to represent macrofauna.

In 2016 only the 12 plots where the crop was winter wheat at phase 3 of the rotation were sampled for soil characterisation (C, N, pH) and soil microbial community assessment (Phospholipid Fatty Acid analysis). In the Simple rotation these plots were previously cropped with two years of wheat. In the Moderate rotation they were previously cropped with a year of oilseed rape (OSR) following a year of wheat. In the Diverse rotation they were previously cropped with a year of spring beans (after a brassica winter cover crop) following wheat under-sown with a legume mixture.

Soils were sampled from the middle three strips of selected subplots in June 2016 and all plots in June 2017, taking five 15 cm deep cores in a ‘W’ layout and homogenising these into one composite sample per plot.