Szabolcs Lengyel

Advantages of Volunteer-Based Biodiversity Monitoring in Europe

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.

Accounting for uncertainty when mapping species distributions: The need for maps of ignorance

Accurate mapping of species distributions is a fundamental goal of modern biogeography, both for basic and applied purposes. This is commonly done by plotting known species occurrences, expert-drawn range maps or geographical estimations derived from species distribution models. However, all three kinds of maps are implicitly subject to uncertainty, due to the quality and bias of raw distributional data, the process of map building, and the dynamic nature of species distributions themselves. Here we review the main sources of uncertainty suggesting a code of good practices in order to minimize their effects. Specifically, we claim that uncertainty should be always explicitly taken into account and we propose the creation of maps of ignorance to provide information on where the mapped distributions are reliable and where they are uncertain.

Grassland restoration on former croplands in Europe: an assessment of applicability of techniques and costs

Grasslands used to be vital landscape elements throughout Europe. Nowadays, the area of grasslands is dramatically reduced, especially in industrial countries. Grassland restoration is widely applied to increase the naturalness of the landscape and preserve biodiversity. We reviewed the most frequently used restoration techniques (spontaneous succession, sowing seed mixtures, transfer of plant material, topsoil removal and transfer) and techniques used to improve species richness (planting, grazing and mowing) to recover natural-like grasslands from ex-arable lands. We focus on the usefulness of methods in restoring biodiversity, their practical feasibility and costs. We conclude that the success of each technique depends on the site conditions, history, availability of propagules and/or donor sites, and on the budget and time available for restoration. Spontaneous succession can be an option for restoration when no rapid result is expected, and is likely to lead to the target in areas with high availability of propagules. Sowing low-diversity seed mixtures is recommended when we aim at to create basic grassland vegetation in large areas and/or in a short time. The compilation of high-diversity seed mixtures for large sites is rather difficult and expensive; thus, it may be applied rather on smaller areas. We recommend combining the two kinds of seed sowing methods by sowing low-diversity mixtures in a large area and high-diversity mixtures in small blocks to create species-rich source patches for the spontaneous colonization of nearby areas. When proper local hay sources are available, the restoration with plant material transfer can be a fast and effective method for restoration.

Ants sow the seeds of global diversification in flowering plants

Background The extraordinary diversification of angiosperm plants in the Cretaceous and Tertiary periods has produced an estimated 250,000–300,000 living angiosperm species and has fundamentally altered terrestrial ecosystems. Interactions with animals as pollinators or seed dispersers have long been suspected as drivers of angiosperm diversification, yet empirical examples remain sparse or inconclusive. Seed dispersal by ants (myrmecochory) may drive diversification as it can reduce extinction by providing selective advantages to plants and can increase speciation by enhancing geographical isolation by extremely limited dispersal distances. Methodology/Principal Findings Using the most comprehensive sister-group comparison to date, we tested the hypothesis that myrmecochory leads to higher diversification rates in angiosperm plants. As predicted, diversification rates were substantially higher in ant-dispersed plants than in their non-myrmecochorous relatives. Data from 101 angiosperm lineages in 241 genera from all continents except Antarctica revealed that ant-dispersed lineages contained on average more than twice as many species as did their non-myrmecochorous sister groups. Contrasts in species diversity between sister groups demonstrated that diversification rates did not depend on seed dispersal mode in the sister group and were higher in myrmecochorous lineages in most biogeographic regions. Conclusions/Significance Myrmecochory, which has evolved independently at least 100 times in angiosperms and is estimated to be present in at least 77 families and 11 000 species, is a key evolutionary innovation and a globally important driver of plant diversity. Myrmecochory provides the best example to date for a consistent effect of any mutualism on large-scale diversification.

Integrating ongoing biodiversity monitoring: potential benefits and methods

Halting the loss of biodiversity comes along with the need to quantify biodiversity composition and dynamics at large spatial and temporal scales. Highly standardized, international monitoring networks would be ideal, but they do not exist yet. If we are to assess changes in biodiversity now, combining output available from ongoing monitoring initiatives is the only option. However, integration of biodiversity information across schemes is still very poorly developed. In this paper, we outline practical issues to be considered when planning to combine existing monitoring information. First, we provide an overview of avenues for integration along the four dimensions that characterize a monitoring design: sample size, biological coverage, spatial coverage and temporal coverage. We also emphasize that complementarity in monitoring targets across schemes enables to describe complex processes of biodiversity dynamics, e.g. through relating species traits to the impacts of environmental changes. Second, we review some methods to overcome differences in designs among monitoring schemes, such as site selection, post-stratification and measurement error. Finally, we point out some commonly used statistical methods that are at hand for combining data or parameter estimates. We especially emphasize the possible levels of data integration (raw data, parameter estimates, or effect size estimates), and the largely under-exploited potential of meta-analysis methods and weighted analyses. This contribution aims to bolster the practice and use of integration of ongoing monitoring initiatives for biodiversity assessment.

National responsibilities in European species conservation: a methodological review.

One particular challenge in reducing the loss of biodiversity by 2010, as agreed on at the Earth Summit in 2002, is to assign conservation tasks to geographic or administrative entities (e.g., countries or regions) on different geographical scales. To identify conservation tasks, it is imperative to determine the importance of a specific area for the global survival of a species. So far, these national or subnational responsibilities for the conservation of species have been included differently in methods prioritizing conservation. We reviewed how 12 European and 3 non-European methods determined national conservation responsibilities and evaluated the international importance of a biological population. Different countries used different methodologies, which made a direct comparison of assessments of national responsibilities among countries extremely difficult. Differences existed in the importance criteria used. Criteria included population decline, range reduction, rarity status, degree of isolation of a population, endemism, proportional distribution, and geographic location. To increase comparability, it is imperative to develop criteria for which data are generally available and to standardize the methodology among countries. A standardized method would allow conservation decisions to be based on the conservation status of a species and on the responsibility of a geographic or administrative entity for the survival of a species. We suggest that such a method should use a scalable index of proportional distribution, taxonomic status, and the distribution pattern of a taxon or species as key elements. Such a method would allow for the creation of hierarchical lists and would be highly relevant for parts of the world with multiple political jurisdictions or state unions and for nations with regional governmental structures. Conservation priorities could then be reasonably set by combining national responsibility assessments with the international conservation status of a species.

A review and a framework for the integration of biodiversity monitoring at the habitat level

The monitoring of biodiversity at the level of habitats is becoming widespread in Europe and elsewhere as countries establish national habitat monitoring systems and various organisations initiate regional and local schemes. Parallel to this growth, it is increasingly important to address biodiversity changes on large spatial (e.g. continental) and temporal (e.g. decade-long) scales, which requires the integration of currently ongoing monitoring efforts. Here we review habitat monitoring and develop a framework for integrating data or activities across habitat monitoring schemes. We first identify three basic properties of monitoring activities: spatial aspect (explicitly spatial vs. non-spatial), documentation of spatial variation (field mapping vs. remote sensing) and coverage of habitats (all habitats or specific habitats in an area), and six classes of monitoring schemes based on these properties. Then we explore tasks essential for integrating schemes both within and across the major classes. Finally, we evaluate the need and potential for integration of currently existing schemes by drawing on data collected on European habitat monitoring in the EuMon project. Our results suggest a dire need for integration if we are to measure biodiversity changes across large spatial and temporal scales regarding the 2010 target and beyond. We also make recommendations for an integrated pan-European habitat monitoring scheme. Such a scheme should be based on remote sensing to record changes in land cover and habitat types over large scales, with complementary field mapping using unified methodology to provide ground truthing and to monitor small-scale changes, at least in habitat types of conservation importance.

Patterns of host ant use by sympatric populations of Maculinea alcon and M. 'rebeli' in the Carpathian Basin

Abstract.Maculinea butterflies show social parasitism via obligatory myrmecophily as their larvae are adopted and raised to pupation by Myrmica ants. Suitable hosts differ for different Maculinea species, and host ant specificity can further differ at the population-level. Although early studies suggested single ant species as main hosts for each Maculinea species, it has recently become clear that their host ant specificity is more complex. Maculinea alcon and Maculinea ‘rebeli’ have variously been separated according to adult and larval morphology, phenology, and their use of different ecosystems, including host plant and host ant species. However, recent genetic evidence has questioned their separation as good species. Here we compare the use of host ants by M. alcon and M. ‘rebeli’ at the regional scale in NE-Hungary and Transylvania (Romania), where molecular studies have found no species-level separation between the two forms. We opened 778 nests of Myrmica ants and searched for Maculinea specimens (larvae, pupae and exuviae) shortly before imago emergence from the nest in seven M. alcon sites, six M. ‘rebeli’- sites and one site where both M. alcon and M. ‘rebeli’ are syntopic. In all, Maculinea caterpillars were found in the nests of seven different ant species (M. alcon was recorded mainly with Myrmica scabrinodis and occasionally with M. salina and M. vandeli; M. ‘rebeli’ used mainly M. scabrinodis, M. sabuleti and M. schencki and occasionally M. lonae and M. specioides). Myrmica scabrinodis was found to be a general host of both M. alcon and M. ‘rebeli’, which is the first record for a common host ant of these two closely related butterflies within the same region. However there were also differences in host ant use patterns between the sites occupied by the two Maculinea taxa, which reflect differences in Myrmica communities between the two types of habitat. Possible explanations for the similar but not identical host use patterns of M. alcon and M. ‘rebeli’, and their relevance for the question of whether they are separate species are discussed.

Assessment of target-organ damage in adolescent white-coat and sustained hypertensives

Aims and scope The aim of the present study was to assess whether a difference exists between intima–media thickness and the left ventricular mass index in healthy nonhypertensive, white-coat hypertensive and sustained hypertensive adolescents. Patients and methods Fifty-nine normotensive and 120 hypertensive adolescents were enrolled in our study. Hypertensive patients were classified into white-coat hypertension (WCH) and sustained hypertension groups based on 24-h ambulatory blood pressure measurements. Both normotensive and hypertensive individuals underwent routine laboratory tests, intima–media thickness measurements on the common carotid arteries and transthoracic echocardiography to measure the left ventricular mass index (LVMI). Results Intima–media thickness was higher both in WCH and sustained hypertension compared with healthy normotensive individuals (controls: 0.048 ± 0.01 cm, WCH: 0.056 ± 0.01 cm, sustained hypertension: 0.054 ± 0.012 cm, both P < 0.001 compared with controls, nonsignificant difference between the two hypertensive groups). There was no difference between the LVMI of control individuals and WCH (LVMI: 35.5 ± 10.3 g/m2.7 and 37.7 ± 11.2 g/m2.7 respectively, P = 0.87). LVMI in sustained hypertension group (LVMI: 44.1 ± 14.1 g/m2.7) was significantly higher both compared with WCH (P < 0.05), and healthy adolescents (P < 0.001). Conclusion Target-organ damage develops in a stepwise fashion in adolescent hypertension. An increased intima–media thickness can be demonstrated not only in the sustained but also in the white-coat form of adolescent hypertension.

Impaired cerebral vasoreactivity in white coat hypertensive adolescents

Background and purpose:  Although its incidence is not high, adolescent hypertension may predict hypertension and increased cardiovascular risk in adulthood. Therefore, the aim of the present study was to assess whether cerebrovascular reactivity is altered in adolescent white coat and sustained hypertensive patients compared to healthy teenagers.