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Schönau-Berzdorf, Germany

Elmer M.,TU Brandenburg | Gerwin W.,TU Brandenburg | Schaaf W.,TU Brandenburg | Zaplata M.K.,TU Munich | And 5 more authors.
Environmental Earth Sciences | Year: 2013

In autumn 2005, the artificial catchment Chicken Creek was completed in an open-cast lignite mine in Lusatia, Germany. The 6 ha area has been constructed as a two-layer system consisting of a clay aquiclude and a sandy aquifer at the top. After construction, the site was left to an unrestricted and unmanaged succession. A comprehensive environmental monitoring program started immediately after the site was completed. Time series of essential environmental parameters were recorded with high temporal and spatial resolution. This paper presents selected time series of the past 6-year ecosystem development. Important changes registered in this period allow for the definition of distinctive phases of the still ongoing initial ecosystem evolution. A primary, short, but pronounced geo-phase-characterized by surface runoff, excessive erosion and sedimentation as well as very rapid immigration of biota-was followed by a hydrological dominated phase with processes, such as groundwater recharge. At the end of the study period, biotic processes became more evident. It can be concluded that the artificial catchment offers unique opportunities for interdisciplinary research on the establishment of an ecological system with rapidly growing complexity. The highly dynamic development of the Chicken Creek catchment provides the possibility to observe manifold changes within short time and to detect feedbacks and their modifications between different ecosystem compartments. © 2013 Springer-Verlag Berlin Heidelberg.

Krause B.,University of Gottingen | Culmsee H.,University of Gottingen | Wesche K.,Senckenberg Museum of Natural History | Bergmeier E.,University of Gottingen | Leuschner C.,University of Gottingen
Biodiversity and Conservation | Year: 2011

Floodplain meadows are severely threatened by land use change and intensification in Central Europe. This study investigates quantitative and qualitative changes in the vegetation of wet and species-rich mesic meadows in the floodplains of north Germany since the 1950s, considering their spatial extent, fragmentation, and replacement by other land use types. Historical high-resolution vegetation maps were compared with recent vegetation surveys in seven study regions (six unprotected areas, one protected reference area) in former West and East Germany. The unprotected sites showed alarming losses in wet and species-rich mesic meadows in the past 50 years (>80%). Wet meadows were substituted by species-poor, intensively managed grasslands (26-60% of the former area), arable fields (0-47%) or set-asides (2-33%). Species-rich mesic meadows were transformed to arable fields (42-72%) or species-poor, intensively managed meadows (14-72%). Decreases in effective mesh size and patch size indicated increasing fragmentation of wet meadows, whilst changes in landscape structure were less consistent in mesic meadows. Only slight changes in the protected floodplain study area indicate that landscape change is mostly caused by local effects such as fertilisation and drainage, but not by general trends such as atmospheric N deposition or climate warming. Despite the contrasting political systems in West and East Germany with different agroeconomic frames, all unprotected study areas showed similar losses and increasing fragmentation of floodplain meadows, which may negatively influence the natural dynamics of, and the gene flow between, meadow plant populations. We conclude that floodplain meadows in north Germany urgently call for high-priority conservation measures. © 2011 The Author(s).

Golovatch S.,RAS A.N. Severtsov Institute of Ecology and Evolution | Evsyukov A.,Lyceum No. 1 Classical | Reip H.,Senckenberg Museum of Natural History
Zootaxa | Year: 2016

The family Polydesmidae is represented in the Caucasus by two genera and 11 species: Polydesmus abchasius Attems, 1898, P. lignaui Lohmander, 1936, P. muralewiczi Lohmander, 1936 and P. mediterraneus Daday, 1889 (all confined to the NW and W Caucasus, but of which only the former three are endemic to the region, whereas the latter species is an introduction), as well as Brachydesmus assimilis Lohmander, 1936 (endemic to most of the region, except Hyrcania), B. pigmentatus Attems, 1951 (= B. pereliae Golovatch, 1976, syn. n.) (subendemic to Hyrcania), B. superus Latzel, 1884 (a cosmopolitan introduction), B. furcatus Lohmander, 1936 (= B. furcatus exiguus Strasser, 1970, syn. n.) (endemic to the NW Caucasus), B. kalischewskyi Lignau, 1915 (= B. karawajewi Lohmander, 1928, = B. ferrugineus Lohmander, 1936, = B. talyschanus Lohmander, 1936, = B. bidentatus Golovatch, 1976, all syn. n.) (a highly polymorphous and widespread species, apparently in a stage of active speciation, subendemic to the entire region), B. kvavadzei sp. n., from Ajaria, Georgia, and B. simplex sp. n., from Abkhazia and Sochi, Krasnodar Province, Russia. All known Caucasian species of Polydesmidae are described in due detail, abundantly illustrated and keyed, and their distributions mapped. Copyright © 2016 Magnolia Press.

Steiner F.M.,University of Innsbruck | Seifert B.,Senckenberg Museum of Natural History | Moder K.,University of Vienna | Schlick-Steiner B.C.,University of Innsbruck
Zoologischer Anzeiger | Year: 2010

Ants of the myrmicine Tetramorium caespitum (Linnaeus, 1758)/T. impurum (Foerster, 1850) complex have challenged taxonomy for long. Schlick-Steiner et al. (2006) made plausible that there are at least seven instead of two species to the complex in the Western Palearctic. Using an increased sample size for increased robustness of the system, we here delimit the alpine species Tetramorium sp. A sensu Schlick-Steiner et al. (2006) against the co-occurring other Western Palearctic species of the complex. The co-occurring species are T. caespitum, T. sp. B sensu Schlick-Steiner et al. (2006) - here treated together because of their extreme morphological similarity - and T. impurum. In a multi-source approach taking advantage of interdisciplinary complementarity, data from male genital morphology and worker morphometrics, thermal niche and mitochondrial DNA are integrated. The unified species concept is applied using the species-delimitation criteria of phenotypic distinctness, thermal niche divergence, reciprocal monophyly and genetic clusters. Tetramorium sp. A is confirmed to be a separate species. Possible synonyms are excluded as names for it based on biogeographic, thermal-niche and worker-morphometric arguments. Tetramorium sp. A is described as Tetramorium alpestre sp.n. It is known from alpine-mat habitats between 1300 and 2335. m above sea level in Austria, France, Italy and Switzerland. T. alpestre is the only Western Palearctic species of the species complex with functionally polygynous nests and supercolonies. Routine identification of workers can be performed using a freely accessible identification tool embedded in the internet, at http://web-resources.boku.ac.at/Discmean/. We discuss our use of species concept, species-delimitation criteria and data analyses as well as the identity of six ambiguous nests and look at some aspects of taking the multisource approach in taxonomy. © 2010 Elsevier GmbH.

Goropashnaya A.V.,Uppsala University | Goropashnaya A.V.,University of Alaska Fairbanks | Fedorov V.B.,University of Alaska Fairbanks | Seifert B.,Senckenberg Museum of Natural History | Pamilo P.,University of Helsinki
PLoS ONE | Year: 2012

Ants of genus Formica demonstrate variation in social organization and represent model species for ecological, behavioral, evolutionary studies and testing theoretical implications of the kin selection theory. Subgeneric division of the Formica ants based on morphology has been questioned and remained unclear after an allozyme study on genetic differentiation between 13 species representing all subgenera was conducted. In the present study, the phylogenetic relationships within the genus were examined using mitochondrial DNA sequences of the cytochrome b and a part of the NADH dehydrogenase subunit 6. All 23 Formica species sampled in the Palaearctic clustered according to the subgeneric affiliation except F. uralensis that formed a separate phylogenetic group. Unlike Coptoformica and Formica s. str., the subgenus Serviformica did not form a tight cluster but more likely consisted of a few small clades. The genetic distances between the subgenera were around 10%, implying approximate divergence time of 5 Myr if we used the conventional insect divergence rate of 2% per Myr. Within-subgenus divergence estimates were 6.69% in Serviformica, 3.61% in Coptoformica, 1.18% in Formica s. str., which supported our previous results on relatively rapid speciation in the latter subgenus. The phylogeny inferred from DNA sequences provides a necessary framework against which the evolution of social traits can be compared. We discuss implications of inferred phylogeny for the evolution of social traits. © 2012 Goropashnaya et al.

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