DOI: 10.5061/dryad.fqz612jth
title: Data from: Functional diversity and habitat preferences of native grassland plants and ground-dwelling invertebrates in private gardens along an urbanisation gradient

description: Urbanisation influences biodiversity and ecosystem functions. However,
 private domestic gardens provide habitats for many species. Challenging
 conditions in urban gardens may support species possessing certain traits,
 but exclude other species. Functional diversity is therefore often altered
 in urban gardens. We surveyed native grassland plants and ground-dwelling
 invertebrates (snails, slugs, spiders, millipedes, woodlice, ants, rove
 beetles), and compiled data on urbanisation (distance to city centre,
 percentage of sealed area) and garden characteristics. We furthermore
 derived data on traits and habitat preferences for the species recorded in
 the gardens from the literature and own measurements. The survey comprised
 35 domestic gardens along a rural-urban gradient in the city of Basel,
 Switzerland and its surroundings.
description: Field survey methods: We selected 35 gardens
 from a pool of 65 candidates offered in response to public calls.
 Selection criteria were the presence of grassland (at least 4
 m<sup>2</sup>), accessibilty to researchers, and
 representation of gardens of different size and management types along the
 rural-urban gradient. Native grassland plants were recorded along a
 zig-zag line in grassland with effort proportional to the size of the
 grassland area in a garden. For total native plant species
 richness used as explanatory variable (see below), we complemented native
 plant species richness in grassland by recording the native plant species
 in the other habitat types along transect lines. These lines ran along the
 long axis of garden features. Furthermore, we considered plants at
 intervals of 2 m along the transect line to measure the height of the
 vegetation, which we used to calculate structural diversity of the
 vegetation. Invertebrates were collected using five pitfall traps and five
 hay bait traps (moist hay in a bag of coarse plastic mesh) in the
 grassland area of a garden. Traps were exposed three times for a week
 each. For gastropods, millipedes and ants, trap collections were
 supplemented by active search (ants: 3 x 15 min, millipedes: 3 x 30 min,
 gastropods: 1 x 30 min and in the case of gastropods sieving of soil
 samples (total 1 litre soil from 5–6 random surface soil samples per
 garden). For rove beetles we did not consider the subfamily
 Pselaphinae. For spiders and woodlice, we only considered adult
 individuals and for ants only workers. In the remaining invertebrate
 groups, we included all individuals that could be determined to the
 species level (99.4% of all individuals sampled). Abundance data was
 pooled over all methods and visits of the biodiversity survey for each
 garden. Collection of data on traits and habitat
 preferences Most data was derived from publications and
 online databases. In a few cases we complemented this with own
 measurements and observations. All sources are listed for the respective
 taxonomic groups in the file
 &lt;Species_traits_sources.docx&gt;. Dates of
 data collection:     Vegetation survey: 2018-07-24 to
 2018-08-20<br>     Invertebrate survey: 2018-05-31 to
 2018-10-18<br>     Survey of garden habitat types and landscape
 variables:<br>     2018-05-31 to 2018-10-18    
 Trait data (from literature): 2018-11-01 to 2019-08-31
 <br> Geographic location of data collection:
 35 private domestic gardens in the city of Basel, its suburbs and
 nearby villages in North-western Switzerland (47˚ 34' N, 7˚ 36'
 E). Information on the street addresses of the gardens is not provided to
 protect the privacy of the garden owners. Software
 used: All data was saved as workbooks in xlsx format
 using Microsoft Excel for Mac Version 16.11.1. A list of sources is given
 as a Microsoft Word docx file. Detailed definitions of variables and data
 files are given in a readme file save as a text file.
description: For native grassland plants and ants only presence (+) or absence
 (-) data is provided. For all other taxoonomic groups abundance data is
 given. Traits and habitat preferences used depend on the taxonomic group.
 For some species not all traits or habitat preferences are known resulting
 in some missing values. Detailed definitions of
 variables, methods used and links to publications from the project are
 available from the readme file accompagning this dataset.