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Aim: (i) To determine whether area and connectivity of temporary ponds can predict plant species diversity, and the diversity and abundance of different plant life histories; (ii) To explore whether pond connectivity with the river prior to river regulation predicts better plant diversity patterns than current pond connectivity, suggestive of possible effects of connectivity loss. Location: Eastern Carpathian Mountains, Romania, Europe. Methods: We fitted linear and generalized linear models (LM and GLM) to examine whether pond area and current distance from the Olt River predict plant species richness, Shannon diversity and relative cover of different social behaviour types and overall plant species richness and Shannon diversity. Using historical maps, we measured pond distance from the river ca. 60 years before the Olt River was regulated, and we refitted the LM and GLM models using pond area and past distance from the river as independent variables. Results: Total plant species richness increased with pond area, and it decreased with the distance from the river, but total plant Shannon diversity index was affected, positively, only by pond area. The strength of responses to pond area and connectivity of species richness, Shannon diversity and relative cover varied across the different social behaviour types. Past and current distances between ponds and riverbeds had similar effects on plant diversity, with some evidence for stronger effect of the present connectivity on specialist species Shannon diversity and a weaker effect on disturbance tolerants, generalists and competitors. Main Conclusions: Pond area and connectivity with the landscape are important predictors of the diversity of plant life history strategies, and therefore, useful tools in pond conservation. Consistent species richness and Shannon diversity responses of wetland specialists to pond area and connectivity make this life history type well suited for monitoring pond condition. [ABSTRACT FROM AUTHOR]

No recent studies on the distribution of calanoid copepods in Romanian inlandwaters are available. During a long-term survey aimed at large branchiopods, we collected two diaptomid species that are new for the fauna of the country, and supplemented the available data on the distribution of other calanoid species with new records. As already observed in the case of large branchiopods, the habitats of the mountain basins of the Eastern Carpathians seem to be characterized by a quite distinct species assemblage. The high calanoid species richness of Romanian inland-waters, and the need for further, more comprehensive surveys aimed at mapping the actual diversity of this order in Romania are stressed. [ABSTRACT FROM AUTHOR]

Landscape ecology is a relatively new and continuously developing field of ecology, whose primary focus is the spatial and temporal heterogeneity of the environment and ecological processes. It has been widely adopted by animal ecologists as well. In this paper we present arguments regarding the need of including the landscape ecological approaches in the study of the distribution of organisms in Romania. Based on the recent developments, we present three conceptual landscape models, the fragmentation model (the most frequently used), the variegation model, and the continuum model. We argue that as first step, the fragmentation model should be applied since it allows a relatively quick survey of a larger area. After the main landscape elements influencing the habitat use of the organism in study were identified using this approach, we propose the variegation or the continuum models at smaller scale, depending on the studied organisms, as a complementary tool for the fragmentation model. Whatever the chosen landscape model / approach might be, it is extremely important to clearly define what is considered to be a landscape (details about the delimitation of patches and / or some measurable parameters of the spatial heterogeneity) in the study and what is the spatial scale considered. The structure of many of our semi-natural landscapes will certainly change in the new, "European Union" era. Without high quality and site-specific data, it will be impossible for engineers and decision makers to incorporate ecological aspects into urban planning and decision making regarding the infrastructural, agricultural or other developements and use of natural resources. [ABSTRACT FROM AUTHOR]

The primary anthropogenic factor causing amphibian declines in Europe is habitat loss and fragmentation. Here we explore the effects of aquatic and landscape habitat variables on the adult counts of the Common Toad (Bufo bufo) in 43 ponds in central Romania surveyed between 2000 and 2005. Principal components analysis (PCA) identified two main factors, with which the adult counts can be related the first related to landscape variables (percentage of forest cover, presence/absence of roads and habitat corridors) and the second, to pond variables, in particular the presence/absence of fish, together accounting for 49% of the total variance. Analysis of variance (ANOVA) showed differences between ponds where toads were present or absent in factor loadings of both principal components, but only the landscape factor was significantly correlated with toad counts. These results highlight the role of landscape composition and configuration in maintaining toad populations in this area, and suggest a negative effect of landscape fragmentation. To efficiently protect amphibians in Romania, appropriate legislation and a close collaboration between landowners, landscape planners and herpetologists are needed. [ABSTRACT FROM AUTHOR]

Fish introductions are considered one of the most widespread anthropogenic threats to aquatic ecosystems. Their negative impact on native amphibian communities has received increasing attention in recent years. We investigated the relationship between the introduced fish, emergent vegetation cover and native amphibians in man-made ponds generated by regulation and dam building along the Târnava Mare Valley (Romania) during the last 40 years. We inventoried amphibians and fish inhabiting 85 permanent ponds and estimated habitat complexity focusing on emergent vegetation cover. Four amphibian species were found to be negatively associated with the presence of predatory fish. Species richness of ponds without fish and ponds without predatory fish did not differ significantly, whereas ponds containing only predatory fish had significantly lower amphibian richness. A significant positive relationship was found between the emergent vegetation cover and pond occupancy of six amphibian species and amphibian species richness. As a management recommendation, we suggest the restriction of fish introductions to non predatory fish and the maintenance of high emergent vegetation cover in the ponds. [ABSTRACT FROM AUTHOR]

Abstract: Amphibians are good indicators of human impact, declining steadily worldwide. We explored the relationships between the ponds and nearby landscape parameters and population size of the Agile Frog (Rana dalmatina), estimated from the number of egg masses, in a cultural landscape within the central section of Târnava Mare Basin, Romania. Forty-three permanent ponds were surveyed in a 2600km2 area. The average number of egg masses per pond was 211.13 (SD=426.41). The egg mass number was significantly and positively related to the emergent aquatic macrophyte cover (its effect peaks at around 50%) and the green connecting corridors between the ponds and forests, and negatively related to the extent of nearby urban areas. The proximity of the forest (positive effect) and the presence of high traffic roads (negative effect) were highly correlated with green corridors and further eliminated from the model due to multicollinearity. Both these variables had significant effects when incorporated in univariate models and multivariate models without green corridors. Since a large part of our study area was currently declared as Natura 2000 site, there is an increased need for management proposals and conservation applications for biodiversity, including amphibians. Rana dalmatina is an important species for monitoring because it is common in the studied area and is suited for short surveys. [Copyright &y& Elsevier]

• Wetland habitat quality indicators of conservationists and herders were compared. • Key indicators were tested along a gradient of ungrazed to heavily grazed sites. • There were no key indicators where the two groups had opposing preferred trends. • Vegetation height, shrub and litter cover decreased with grazing intensity. • Forage grasses and frequency of rare mud species increased with grazing intensity. Wetland grazing by livestock, once widespread throughout Europe, is increasingly used in conservation management. To avoid conflicts and enable cooperation between wetland users and conservationists, habitat quality indicators relevant to both stakeholder groups would be useful. We aimed to identify which indicators of grazed wetland habitat quality are important to the two groups, and which are the preferred trends for these indicators along a grazing intensity gradient. We conducted free listing interviews with 15 conservationists and 15 herders to identify the key indicators of well managed, extensively grazed wetland habitats. To check the practical ecological relevance of these indicators, vegetation surveys were performed along a gradient from ungrazed to heavily grazed stands (45 sites) in three countries: Hungary, Romania and Serbia. Positive trends for herders included increases in useful forage grasses and decreases in tall-growing marsh species; for conservationists, increases in wetland birds, protected and threatened plant species, habitat heterogeneity, and patches of open vegetation were all positive. Grazed marshes had lower vegetation cover and height, less litter cover and fewer shrubs. The proportion of open surfaces and the frequency of rare mud species and protected species increased along the grazing intensity gradient. As grazing intensified, 73% of the 15 vegetation attributes assigned to the indicators changed in a 'positive' direction, half of them significantly, showing the benefits of extensive but patchy heavy grazing. Despite differences in perceived benefits, there were no opposing preferred trends for any of the studied indicators, so patchy, occasionally and locally intense or heavy wetland grazing by livestock in these landscapes was beneficial for herding and conservation alike. In the situation of mosaic-like, carefully herded extensive grazing, there was no trade-off between conservation management and utilisation. [ABSTRACT FROM AUTHOR]

Traditional haymaking has created exceptionally high levels of plant species diversity in semi-natural grasslands of the Carpathian Mountains (Romania), the maintenance of which is jeopardized by recent abandonment and subsequent vegetation succession. We tested the hypothesis that the different life history strategies of dominant grasses cause different patterns of diversity loss after abandonment of traditional haymaking in two types of meadow. Although diversity loss rate was not significantly different, the mechanism of loss depended on the life history of dominant species. In meadows co-dominated by competitive stress-tolerant ruderals, diversity loss occurred following the suppression of dominant grasses by tall forbs, whereas in meadows dominated by a stress-tolerant competitor, diversity loss resulted from increased abundance and biomass of the dominant grass. We conclude that management for species conservation in abandoned grasslands should manipulate the functional turnover in communities where the dominant species is a weaker competitor, and abundance and biomass of dominant species in communities where the dominant species is the stronger competitor.