DOI: 10.5061/dryad.5dk66
title: Data from: Conservation of pollinators in traditional agricultural landscapes – new challenges in Transylvania (Romania) posed by EU accession and recommendations for future research

description: Farmland biodiversity is strongly declining in most of Western Europe, but
 still survives in traditional low intensity agricultural landscapes in
 Central and Eastern Europe. Accession to the EU however intensifies
 agriculture, which leads to the vanishing of traditional farming. Our aim
 was to describe the pollinator assemblages of the last remnants of these
 landscapes, thus set the baseline of sustainable farming for pollination,
 and to highlight potential measures of conservation. In these traditional
 farmlands in the Transylvanian Basin, Romania (EU accession in 2007), we
 studied the major pollinator groups—wild bees, hoverflies and butterflies.
 Landscape scale effects of semi-natural habitats, land cover diversity,
 the effects of heterogeneity and woody vegetation cover and on-site flower
 resources were tested on pollinator communities in traditionally managed
 arable fields and grasslands. Our results showed: (i) semi-natural
 habitats at the landscape scale have a positive effect on most
 pollinators, especially in the case of low heterogeneity of the direct
 vicinity of the studied sites; (ii) both arable fields and grasslands hold
 abundant flower resources, thus both land use types are important in
 sustaining pollinator communities; (iii) thus, pollinator conservation can
 rely even on arable fields under traditional management regime. This has
 an indirect message that the tiny flower margins around large intensive
 fields in west Europe can be insufficient conservation measures to restore
 pollinator communities at the landscape scale, as this is still far the
 baseline of necessary flower resources. This hypothesis needs further
 study, which includes more traditional landscapes providing baseline, and
 exploration of other factors behind the lower than baseline level
 biodiversity values of fields under agri-environmental schemes (AES).
description: Sampling data of wild
 bees and hoverflies in TransylvaniaMetadata of the dataset
 used by the following paper accepted in Plos One in March 2016 (Ref. No:
 PONE-D-15-36138R1). These pollinator data were sampled by transect walk
 method in Transylvanian arable fields and grasslands in 2012, in a case
 study financed by the "Lendület" program of the Hungarian
 Academy of Sciences. Guideline for abbreviations used in the name of
 variables is provided in the file.PONE-D-15-36138_datarepository.xlsxSpecies list of wild beesSpecies list of wild bees with their abundance (number of individuals) in arable fields and grasslands, lecty category and conservation interest in the studied arable fields and grasslands in Transylvania, Romania. IUCN European Red bee list categories are presented at geographical Europe scale (EN – Endangered; VU – Vulnerable; NT – Near Threatened; LC – Least Concern; DD – Data Deficient).PONE-D-15-36138R1_S2_Table.docxSpecies list of hoverfliesSpecies list of hoverflies with their abundance (number of individuals) in the studied arable fields and semi-natural grasslands in Transylvania, Romania.PONE-D-15-36138R1_S3_Table.docxGoogle Earth map of the studied arable fields and grasslandsSites were assigned in the vicinity of 19 villages in the Transylvanian Basin, Romania. Sites are named by the first three letters of the closest village, A (arable) or P (grassland) indicates the land use type, plus H (heterogeneity) and W (woody vegetation cover) values in a 3 value range. Heterogeneity was defined as the standard deviation of the 2.5m panchromatic Spot picture, stratified in quantiles: H1 – belonging to lower third (low heterogeneity), H2 – middle third, H3 – upper third. Woody vegetation cover represented the proportion of woody vegetation (shrubs and trees) in a 1 ha circle based on classified 10m SPOT 5 data: W1: 0 to 5 % woody vegetation cover; W2: 5 to 15 % of woody vegetation; W3: 15 to 50 % of woody vegetation (1 – low, 2 – middle, 3 – high).PONE-D-15-36138R1_S1_Figure.kml