Without robust and unbiased systems for monitoring, changes in natural systems will remain enigmatic for policy makers, leaving them without a clear idea of the consequences of any environmental policies they might adopt. Generally, biodiversity-monitoring activities are not integrated or evaluated across any large geographic region. The EuMon project conducted the first large-scale evaluation of monitoring practices in Europe through an on-line questionnaire and is reporting on the results of this survey. In September 2007 the EuMon project had documented 395 monitoring schemes for species, which represents a total annual cost of about 4 million euro, involving more than 46,000 persons devoting over 148,000 person-days/year to biodiversity-monitoring activities. Here we focused on the analysis of variations of monitoring practices across a set of taxonomic groups (birds, amphibians and reptiles, mammals, butterflies, plants, and other insects) and across 5 European countries (France, Germany, Hungary, Lithuania, and Poland). Our results suggest that the overall sampling effort of a scheme is linked with the proportion of volunteers involved in that scheme. Because precision is a function of the number of monitored sites and the number of sites is maximized by volunteer involvement, our results do not support the common belief that volunteer-based schemes are too noisy to be informative. Just the opposite, we believe volunteer-based schemes provide relatively reliable data, with state-of-the-art survey designs or data-analysis methods, and consequently can yield unbiased results. Quality of data collected by volunteers is more likely determined by survey design, analytical methodology, and communication skills within the schemes rather than by volunteer involvement per se.

Monitoring of biodiversity at the level of habitats is becoming increasingly common. Here we describe current practices in habitat monitoring based on 150 schemes in Europe. Most schemes were initiated after 1990 in response to EU nature directives or habitat management/restoration actions, with funding mostly from European or national sources. Schemes usually monitor both the spatial distribution and the quality of the habitats, and they frequently collect data on environmental parameters and potential causes

Question European landscapes have long been influenced by intensifying use by humans. Although habitat restoration can reverse this process, it is often limited in scope by socioeconomic constraints. Here we present a grassland restoration project that is exceptional in spatial scale in Europe. Location A total area of 760 ha of arable land was restored in the Egyek‐Pusztakócs unit (50 km2) of Hortobágy National Park, east Hungary, between 2005 and 2008. Methods Restoration targeted alkali steppes and loess grasslands by sowing seeds of either two (alkali) or three (loess) foundation grass species. In 2009, we surveyed the vegetation in restored and target grasslands and quantified the factors influencing restoration success in a space‐for‐time substitution design. Results We recorded 100 species of flowering plants, of which 37 species were non‐weed, ‘target’ species. Annual weeds dominated 1‐yr‐old fields but had decreased dramatically by the third year due to a developing perennial grass cover. Former alfalfa fields had proportionally fewer weeds than former cereal and sunflower fields. The diversity of common species and the cover of target species increased from 1‐ to 4‐yr‐old restored fields. Alkali‐restored fields had more heterogeneous vegetation and more species than loess‐restored fields. Distance to the target vegetation did not directly affect vegetation variables. There was significant spatial variability in vegetation development, possibly suggesting several local pathways of succession. Conclusions Grassland restoration was generally successful in accelerating secondary succession towards alkali steppes and loess grasslands. However, further management is necessary to counter the homogenizing effects of litter accumulation, to reduce perennial weeds and to enhance the colonization of target species. Our project provides useful practical insights into grassland restoration and in applying restoration at a number of sites within a larger area to conserve biodiversity at the landscape scale.

Habitat diversity (spatial heterogeneity within and between habitat patches in a landscape, HD) is often invoked as a driver of species diversity at small spatial scales. However, the effect of HD on species richness (SR) of multiple taxa is not well understood. We quantified HD and SR in a wet-dry gradient of open grassland habitats in Hortobágy National Park (E-Hungary) and tested the effect of compositional and structural factors of HD on SR of flowering plants, orthopterans, true bugs, spiders, ground beetles and birds. Our dataset on 434 grassland species (170 plants, 264 animals) showed that the wet-dry gradient (compositional HD at the between-patch scale) was primarily related to SR in orthopterans, ground-dwelling arthropods, and all animals combined. The patchiness, or plant association richness, of the vegetation (compositional HD at the within-patch scale) was related to SR of vegetation-dwelling arthropods, whereas vegetation height (structural HD at the within-patch scale) was related to SR of ground-dwelling arthropods and birds. Patch area was related to SR only in birds, whereas management (grazing, mowing, none) was related to SR of plants and true bugs. All relationships between HD and SR were positive, indicating increasing SR with increasing HD. However, total SR was not related to HD because different taxa showed similar positive responses to different HD variables. Our findings, therefore, show that even though HD positively influences SR in a wide range of grassland taxa, each taxon responds to different compositional or structural measures of HD, resulting in the lack of a consistent relationship between HD and SR when taxon responses are pooled. The idiosyncratic responses shown here exemplify the difficulties in detecting general HD-SR relationships over multiple taxa. Our results also suggest that management and restoration aimed specifically to sustain or increase the diversity of habitats are required to conserve biodiversity in complex landscapes.

Agricultural intensification threatens grasslands worldwide and the restoration of grasslands from arable lands can at least partially counter this threat. We studied grassland restoration by following early successional changes of arthropod assemblages (spiders -Araneae, true bugs -Heteroptera, orthopterans -Orthoptera and ground beetles -Carabidae) on one-and two-year-old restorations using arable lands and native grasslands as two ends of the succession timescale. To examine the changes in species composition among the habitat types, we used habitat affinity indices based on fidelity and/or specificity of the species. We found that the number of species did not differ between habitat types, while species composition changed markedly with time. Species richness was thus not adequate to detect favorable changes after grassland restoration.Habitat affinity indices, on the other hand, were useful to detect compositional changes caused by the increasing numbers of species characteristic of target grasslands as early as the second year after restoration. Habitat affinity indices are easy-to-use, easy-tointerpret measures of restoration success; therefore, we recommend their use as measures complementary to species richness and simple similarity. Our results show that sowing low-diversity seed mixture followed by mowing and grazing can be particularly successful in grassland restoration in time periods as short as two years.