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Sighișoara, Romania

Hartel T.,Mihai Eminescu Trust | Hartel T.,Ovidius University | Hartel T.,Netherlands Center for Biodiversity Naturalis | Bancila R.,Ovidius University | And 2 more authors.
Freshwater Biology | Year: 2011

1.Habitat loss is a major driver of biodiversity decline worldwide. Temporary waterbodies are especially vulnerable because they are sensitive both to human impact and to climatic variations. Pond-breeding amphibians are often dependent on temporary waterbodies for their reproduction, and hence are sensitive to loss of temporary ponds. 2.Here we present the results of a 5-year study regarding the use of temporary aquatic habitats by amphibians in a hydrologically modified area of Eastern Europe (Romania). The annual number of aquatic habitats varied between 30 and ~120. Each aquatic habitat was characterised by a number of variables such as: 'type' (pond, drainage ditch and archaeological ditch), 'hydroperiod' (number of weeks the ponds were filled in a given year), 'depth' (cm), 'area' (m2) and the density of predatory insects ('predation'). The turnover rate for each amphibian species for each wetland was calculated based on the pond occupancy. 3.Eight amphibian species were recorded from the aquatic habitats. Hydroperiod was the most important variable, positively influencing wetland use by amphibians and their reproductive success. Most species preferred drainage ditches for reproduction, and the reproductive success was highest in this habitat type every year. For most of the species, the local extinction rate was higher than the colonisation rate in the first 4years, but the situation reversed in the last year of the study when wetland use by amphibians sharply increased because of high rainfall. 4.This study confirms the importance for amphibians of maintaining and managing aquatic habitat diversity at small spatial scales. Man-made aquatic habitats such as drainage ditches may be important habitats for amphibians, and this should be considered in restoration activities. © 2011 Blackwell Publishing Ltd. Source


Balog A.,Yale University | Balog A.,Sapientia University | Ferencz L.,Sapientia University | Hartel T.,Mihai Eminescu Trust
Journal of Insect Science | Year: 2011

A five-year research project was performed to explore the potential effects of contact insecticide applications on the change of abundance and species richness of predatory rove beetles (Coleoptera: Staphylinidae) in conventionally managed orchards. Twelve blocks of nine orchards were used for this study in Central Europe. High sensitivity atomic force microscopic examination was carried out for chitin structure analyses as well as computer simulation for steric energy calculation between insecticides and chitin. The species richness of rove beetles in orchards was relatively high after insecticide application. Comparing the mean abundance before and after insecticide application, a higher value was observed before spraying with alphacypermethrin and lambda-cyhalothrin, and a lower value was observed in the cases of diflubenzuron, malathion, lufenuron, and phosalone. The species richness was higher only before chlorpyrifos-methyl application. There was a negative correlation between abundance and stability value of chitin-insecticides, persistence time, and soil absorption coefficients. Positive correlation was observed with lipo- and water solubility. Source


Tryjanowski P.,University of Life Sciences in Poznan | Hartel T.,Mihai Eminescu Trust | Bldi A.,Hungarian Academy of Sciences | Szymanski P.,Polish Academy of Sciences | And 18 more authors.
Acta Ornithologica | Year: 2011

Birds are commonly used as an example of the strongly declining farmland biodiversity in Europe. The populations of many species have been shown to suffer from intensification of management, reduction of landscape heterogeneity, and habitat loss and fragmentation. These conditions particularly dominate farmland in the economically well developed countries of Western Europe. Currently, the farmland environment in Central-Eastern Europe is generally more extensive than in Western Europe and a larger proportion of people still live in rural areas; thus generating different conditions for birds living in agricultural areas. Furthermore, the quasi-subsistence farming in much of Central-Eastern Europe has resulted in agricultural landscapes that are generally more complex than those in Western Europe. To protect declining bird populations living in farmland, detailed knowledge on both species and communities is necessary. However, due to scientific tradition and availability of funding, the majority of studies have been carried out in Western Europe. In consequence this provokes a question: are findings obtained in western conditions useful to identify the fate of farmland bird biodiversity in Central-Eastern Europe? Therefore, the major goal of this paper is to highlight some local and regional differences in biodiversity patterns within EU farmland by comparing intensive agricultural landscapes with more extensive ones. More specifically, we aim to outline differences in agricultural landscapes and land use history in the two regions, use farmland birds to provide examples of the differences in species dynamics and species-habitat interactions between the two regions, and discuss possible social and ecological drivers of the differences in the context of biodiversity conservation. Factors governing spatio-temporal dynamics of farmland bird populations may differ in intensive and extensive landscapes as illustrated here using the Grey Partridge Perdix perdix and the Red-backed Shrike Lanius collurio as examples. The unevenness of farmland bird studies distribution across Europe was also presented. We call for more emphasis on pluralism in furthering both pan-European research on farmland bird ecology and conservation strategies. We also highlight some features specific to Central-Eastern Europe that merit consideration for the more efficient conservation of farmland birds and farmland biodiversity across Europe. Source


Hartel T.,Mihai Eminescu Trust | Hartel T.,Babes - Bolyai University | Hartel T.,Netherlands Center for Biodiversity Naturalis | Nemes S.,Mihai Eminescu Trust | And 4 more authors.
Environmental Conservation | Year: 2010

Spatial models are increasingly employed to help understand the distribution of organisms and establish conservation priorities. Classic patch-orientated models may have limited power to accurately predict the organisms' distributions. Pond breeding amphibians are appropriate study organisms because of their complex life cycle, low dispersal and sensitivity to environmental conditions. Here connectivity metrics and niche modelling were used to predict the occurrence of the northern crested newt in a rural landscape from central Romania. Pond-related variables, such as macrophyte cover and the presence of predatory fish, were the most important predictors of newt occurrence, followed by one landscape-related variable (urbanization) and a connectivity metric (nearest neighbouring occupied pond). Most of the landscape and connectivity variables were not adequate predictors, presumably because most of the terrestrial habitats in this traditionally used rural landscape are ecologically optimal for amphibians. Conservation measures for the northern crested newt should promote the preservation of traditional extensive agricultural practices and discourage stocking of ponds with predatory fish. Copyright © Foundation for Environmental Conservation 2010. Source


Moga C.I.,Mihai Eminescu Trust | Hartel T.,Mihai Eminescu Trust | Ollerer K.,Romanian Academy of Sciences | Szapanyos A.,Mihai Eminescu Trust
Belgian Journal of Zoology | Year: 2010

In this paper we present dasta relating to nest density and habitat use by the Lesser Grey Shrike Lanius minor in the Târnava Mare Valley, Romania, using both nesting tree parameters (microhabitat), and habitat parameters measured in a 100m radius around each nest. The density of nests was 0.96 per km 2. Average distance between nests was 768.4m. Most of the nests (94.1%) were found in poplars, in the region of the middle third of their trunk, especially at the terminal parts of the branches. The birds preferred open habitats, with extended arable field cover. Moreover, the tree and shrub cover were small in areas used for nesting. As poplars are the preferred nesting habitats of this bird, and are scarcely represented in this area, the protection of these trees is critical for conservation of the Lesser Grey Shrike. Source

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