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During the 2016 field season, we investigated the influence of intense nest digging predation at a Sand Martin colony that is situated in natural habitat along the Tisza river. Over this season, foxes dug a large number of holes which either partly or fully destroyed 39% of burrows in a large colony, comprising over 1,500 pairs. This high level of predation caused death and/or injury to between 7% and 44% of breeding individuals and lowered the reproductive success of the colony as on average 20% (between 5% and 43%) less nestlings were fledged. The level of digging showed a negative exponential growth with burrow density. Our observations show that the burrows were most at threat between 0 m and 0.4 m from the top and between 0 m and 1.4 m from the bottom of the wall. These observations show that it is critically important to decrease the number of foxes and other potential nest predators, whose numbers have increased well above ‘natural’ levels over the last decade, in regions where Sand Martins are nesting as this species is in drastic decline.

New Ar–Ar muscovite and Rb–Sr biotite age data in combination with structural analyses from the Apuseni Mountains provide new constraints on the timing and kinematics of deformation during the Cretaceous. Time–temperature paths from the structurally highest basement nappe of the Apuseni Mountains in combination with sedimentary data indicate exhumation and a position close to the surface after the Late Jurassic emplacement of the South Apuseni Ophiolites. Early Cretaceous Ar–Ar muscovite ages from structurally lower parts in the Biharia Nappe System (Dacia Mega-Unit) show cooling from medium-grade conditions. NE–SW-trending stretching lineation and associated kinematic indicators of this deformation phase (D1) are overprinted by top-NW-directed thrusting during D2. An Albian to Turonian age (110–90 Ma) is proposed for the main deformation (D2) that formed the present-day geometry of the nappe stack and led to a pervasive retrograde greenschist-facies overprint. Thermochronological and structural data from the Bihor Unit (Tisza Mega-Unit) allowed to establish E-directed differential exhumation during Early–Late Cretaceous times (D3.1). Brittle detachment faulting (D3.2) and the deposition of syn-extensional sediments indicate general uplift and partial surface exposure during the Late Cretaceous. Brittle conditions persist during the latest Cretaceous compressional overprint (D4). Electronic supplementary material The online version of this article (doi:10.1007/s00531-016-1335-y) contains supplementary material, which is available to authorized users.

The vertical profiles of 20 major and trace metals were investigated along a 180-cm-long sediment core, which was sampled at Kiss-Janosne-Holt Tisza, an oxbow lake located in the upper part of the Tisza River in Hungary. The vertical profiles showed sharp peaks at different depths, reflecting historical pollution events and unusual changes of river water characteristics. Five different groups of metals, containing metals which were strongly correlated and showing a similar behaviour, could be distinguished by factor analysis. Six areas, with variable degrees and types of contamination, were classified in the sediment core with cluster analysis. The most polluted sections were found in the upper 50-cm part (significantly contaminated by Cu, Zn, Pb, Cd and Hg) and the deeper 100120-cm part (characterised by high concentrations of metals associated with mining activities, such as Fe and Mn, as well as Cu, Zn and Pb). In recent years, important pollution events, such as the one which took place in March of 2000, were the reason for pollution of the upper sediment layers, whereas mining activities during the last century were responsible for the pollution of the deeper core sections.

"Climatic hazards such as floods and droughts have always been a primary matter of concern for human populations. Severe floods damage settlements, transport networks, and arable land. Although devastating droughts are harmful primarily for agriculture and terrestrial ecosystems, they can also lead to local water supply shortages. Despite significant achievements in science and technology and success stories in environmental management in the 20th century, people still continue to suffer the consequences of climate hazards worldwide. This paper provides an overview of existing practices for coping with floods and droughts, compares strategies in different river basins, and outlines the areas that need improvement. First, the existing protection measures and response strategies against floods and droughts are briefly described. An overview is given of expected climate change and existing coping strategies for floods and droughts in seven case study basins. Four of the basins, namely the Elbe, Guadiana, Rhine, and Tisza, are located in Europe; the Nile and the Orange are in Africa; and the Amudarya is in Central Asia. Analysis of the coping strategies shows that structural measures exist in all seven river basins, but that nonstructural measures are generally not very extensive and/or advanced. Finally, the success stories in dealing with climatic hazards and lessons learned, taken partly from the seven case study basins and partly from literature, are summarized."