Investigation of the vulnerability of a partly covered karst feature in Veszprém, Hungary.

Karst aquifers represent the most important renewable sources of drinking water. Because anthropogenic influences threaten the integrity of karst aquifers, it is important to determine the soil erosion and karst denudation rates. In order to study the complex signs of degradation processes of the karst, a paleodoline (paleo-polje) was selected near to the county seat Veszprém, Hungary. It was found that gamma radiation measurements can be a useful tool to detect the level of soil erosion since the low gamma radiation indicates the surface proximity of the carbonate bedrock. The level of gamma radiation also predicts the potential agricultural usability of a site. Both the patterns of contamination and the erosion attack zone are strongly defined by the relief. The gullies and the deepest parts of the karstic landscape are the traps of organic materials and pollutants. The amounts of 40K and its decay products originate from the covering sediment and negatively correlate with the soil depth. In the case of covered karsts, the measuring of the concentration of radionuclides and field gamma-ray dose measurement together can characterize the general horizontal and vertical trends of soil erosion, the potential land use, and the vegetation.

Influence of physical factors of apartments, educational attainment, nationality and unemployment on the number of Cimex lectularius inquiries.

OBJECTIVE: The aim of the study was to determine the effect of physical factors of apartments, educational attainment, nationality and unemployment on the number and distribution of bed bug call inquiries in Budapest, Hungary. METHODS: Educational attainment, apartment conditions, the level of unemployment, the ratio of dependent people in the households, nationality and proportion of dependent people were selected as regressors. Monthly ambient temperature values were correlated with monthly call inquiry numbers. RESULTS: Downtown units showed the highest call inquiry rates. Significant positive correlations were found between the call inquiry rates and the ratio of low educational attainment inhabitants (people with ≤ 8 school classes), the rate of small floor area apartments (apartment area < 29 m2), proportions of the comfortless apartments in the district housing stock and proportion of unemployed people on district level as well as proportion of gypsy inhabitants in the districts. Significant negative correlation was found between the call inquiry rates and the average area (m2) of apartments. The number of call inquiries showed expressed, temperature-depending seasonality between March and December 2015. In multiple regression analyses, the level of unemployment and proportion of gypsy inhabitants showed significant correlations with the rate of bed bug call inquiries. CONCLUSIONS: Apartment conditions, educational attainment, nationality, unemployment, and the city structure have notable influence on the occurrence of bed bug call inquiries on urban level, although the level of unemployment and nationality seem to be the strongest factors. The annual changes of the ambient temperature have effect on the call inquiry rate.

Impact of urbanization on abundance and phenology of caterpillars and consequences for breeding in an insectivorous bird.

Urbanization can have marked effects on plant and animal populations' phenology, population size, predator-prey, interactions and reproductive success. These aspects are rarely studied simultaneously in a single system, and some are rarely investigated, e.g., how insect phenology responds to urban development. Here, we study a tri-trophic system of trees, phytophagous insects (caterpillars), and insectivorous birds (Great Tits) to assess how urbanization influences (1) the phenology of each component of this system, (2) insect abundance, and (3) avian reproductive success. We use data from two urban and two forest sites in Hungary, central Europe, collected over four consecutive years. Despite a trend of earlier leaf emergence in urban sites, there is no evidence for an earlier peak in caterpillar abundance. Thus, contrary to the frequently stated prediction in the literature, the earlier breeding of urban bird populations is not associated with an earlier peak in caterpillar availability. Despite this the seasonal dynamics of caterpillar biomass exhibited striking differences between habitat types with a single clear peak in forests, and several much smaller peaks in urban sites. Caterpillar biomass was higher in forests than urban areas across the entire sampling period, and between 8.5 and 24 times higher during the first brood's chick-rearing period. This higher biomass was not associated with taller trees in forest sites, or with tree species identity, and occurred despite most of our focal trees being native to the study area. Urban Great Tits laid smaller clutches, experienced more frequent nestling mortality from starvation, reared fewer offspring to fledging age, and their fledglings had lower body mass. Our study strongly indicates that food limitation is responsible for lower avian reproductive success in cities, which is driven by reduced availability of the preferred nestling diet, i.e., caterpillars, rather than phenological shifts in the timing of peak food availability.

Decoupling of active and passive reasons for the invasion dynamics of Aedes albopictus Skuse (Diptera: Culicidae): Comparisons of dispersal history in the Apennine and Florida peninsulas.

Aedes albopictus is an important vector of several diseases including dengue- and Chikungunya fever and is a potential vector of Zika-fever. The invasion dynamics of Aedes albopictus was reconsidered by comparing the temperature-related development of the mosquito with the observed real geographical distribution in Florida and in Italy. The potential number of generations and the annual dispersal distances of the mosquito were calculated for the estimates. The estimated total dispersals are 3.6-4.6 km/year/generation in Italy and 4.6-5.3 km/year/generation in Florida, values that are at least five to six times higher than those derived from release and recapture studies and from the previously measured flying distances of female Asian tiger mosquitoes. Subtracting the calculated dispersal distances with the known active dispersal of female Ae. albopictus, the passive dispersal component of the total dispersal distances was found to be 2.8-4.1 km/year/generation in Italy and 3.8-4.8 km/year/generation in Florida. Our results confirm that the active dispersal of female mosquitoes plays a secondary role in determining the rate of areal expansion and, in contrast, passive factors may play a primary role. It was concluded, based on similar average values of the passive dispersal distances of the mosquito in Florida and Italy, that at large spatial scales the anthropogenic component can be well estimated.