Über die Cladocerenfauna des Feldungelsees bei Engter

1. Von 1963 bis 1968 wurden das Vorkommen und die Verteilung der Cladocerenarten im Feldungelsee, einem Erdfallsee bei Engter (Reg.-Bez. Osnabrück), untersucht. Es wurden 33 Arten festgestellt. 2. Diaphanesoma brachyurum, Daphnia cucullata, Ceriodaphnia quadrangula und Bosmina longirostris sind die am häufigsten im PelagiaI lebenden Arten. Nur bei Diaphanosoma und Ceriodaphnia wurden Massenentwicklungen beobachtet. 3. Im LitoraI gab es ein massenhaftes Auftreten bei Scapholeberis mucronata, Ceriodaphnia quadrangula und Peracantha truncata. Am individuenreichsten und artenreichsten waren das Röhricht und die Menyanthes-Bestände am Südufer. 4. Von den im BodenschIamm lebenden Arten traten Alona quadrangularis und Alonella rostrata durch Häufigkeit hervor. Iliocryptus agilis war häufiger als I. sordidus, Camptocercus rectirostris nicht selten, obwohl das Gewässer nicht kalkarm ist. 5. Anchistropus emarginatus wurde erstmalig in Nordwestdeutschland nachgewiesen. Es muß noch geklärt werden, welche Hydra-Art als Wirt dient. 6. In weiteren Untersuchungen soll versucht werden, Gründe für das Fehlen von Polyphemus pediculus zu finden. 7. Von mehreren Arten wurden Exemplare mit mißgestalteten Hinterkörpern und Schalenrändern gefunden. Auffallend häufig traten die Mißbildungen im Oktober 1963 bei Peracantha truncata auf.1. From 1963 to 1968 investigations have been made about the occurrence and distribution of the cladoceran fauna in the Feldungelsee near Engter (District of Onabrück). 33 species have been found. 2. Diaphanosoma brachyurum, Daphnia cucullata, Ceriodaphnia quadrangula and Bosmina longirostris were the most frequent species in the plankton, but only Diaphanosoma and Ceriodaphnia were found in great numbers. 3. In the littoral Scapholeberis mucronata, Ceriodaphnia quadrangula and Peracantha truncata were very frequent. Greatest numbers of individuals and species were found among Menyanthes and Phragmites on the south shore. 4. Alona quadrangularis and Alonella rostra ta are the most abundant among those species living in the mud. Iliocryptus agilis was more frequent than I. sordidus; Camptocercus rectirostris was not seldom although there is no lack of calcium. 5. Anchistropus emarginatus was found in Northwest Germany for the first time. It is to be examined on which species of Hydra Anchistropus is parasitic in the Feldungelsee. 6. Reasons for the absence resp. the disappearance of Polyphemus pediculus are to be found out by further investigations. 7. Several specimens of different species with deforrnities of abdomen and shell were found. Surprisingly frequent deformities occurred with Peracantha truncata in October 1963

Tretocephala ambigua (LILLJEBORG, 1990) : eine seltene Chydoride aus dem Dümmergebiet (Branchiopoda: Anomopoda)

Die seltene Chydoride Tretocephala ambigua wurde von 1984-1993 im Sickergraben östlich des Dümmerdeiches (Niedersachsen) gefunden. Dies ist der fünfte Fundort in Deutschland. Männchen und Sexualweibchen traten im Oktober auf.The rare chydorid Tretocephala ambigua was found in the ditch east of the Duemmer dam (Lower Saxony) frorn 1984-1993. This is the fifth record in Germany. Males and sexual females appeared in October

Veränderungen der Cladocerenfauna des Feldungelsees in den letzten 25 Jahren

Die Cladocerenfauna des eutrophen Feldungelsees nördlich von Osnabrück wurde 1990-1994 untersucht; die Ergebnisse werden mit den Untersuchungen 1963-1968 verglichen. Es wurden jetzt 34 Arten festgestellt; 5 Arten wurden nicht wiedergefunden, 4 Neuzugänge wurden nachgewiesen: Alone/la nana, Pleuroxus aduncus und zwei Daphnia-Arten, die aus Amerika stammenden D. ambigua und D. parvula. Eine auf Grund der negativen Vegetationsentwicklung im Feldungelsee zu vermutende starke Veränderung der Cladocerenfauna ist nicht eingetreten.The cladoceran fauna of the eutrophie Feldungelsee north of Osnabrück was investigated between 1990 and 1994. The results are compared with previous investigations between 1963 and 1968. Now 34 species of Cladocera were found; 5 species were absent, 4 species had newly invaded the lake: Alone/la nana, Pleuroxus aduncus and two Daphnia-species from North-America, D. ambigua and D. parvula. The expected severe changes in the cladoceran fauna due to the negative development of the vegetation have not taken place

Cladoceren-Funde in der oberen und mittleren Hase (1966-1969) : mit 2 Tabellen

Die Cladoceren-Funde im Rahmen der Untersuchung der oberen und mittleren Hase und ihr Aussage-Wert über den Biotop werden erörtert und in 2 Tabellen zusammengefaßt

Zur Cladocerenfauna des Feldungelsees (1995-98) im Vergleich mit früheren Untersuchungen und zur Ostracodenfauna (1995-98)

Von 1995 bis 1998 wurde die Cladoceren- und Ostracodenfauna des eutrophen Feldungelsees nördlich Osnabrück untersucht. Die Anzahl der Cladocerenarten ist gegenüber einer früheren Untersuchung auf 39 gestiegen. Ceriodaphnia laticaudata, Megafenestra aurita und Simocephalus exspinosus v. congener traten erstmalig im See auf. Die zwei Daphnia-Arten aus Nordamerika, D. ambigua und D. parvula, bewohnen weiterhin den See. 1995 wurden die jahreszeitliche Verbreitung und die Sexual perioden untersucht. Bei den meisten Cladocerenarten wurde Monozyklie beobachtet, 3 Arten traten dizyklisch auf. 17 Muschelkrebsarten wurden nachgewiesen, die für diese Gegend und diesen Lebensraum charakteristisch sind.Between 1995 and 1998 the cladoceran and ostracod fauna of the eutrophie Feldungelsee north of Osnabrück was investigated. Compared with former investigations the number of cladoceran species has increased to 39. Ceriodaphnia laticaudata, Megafenestra aurita and Simocephalus exspinosus v. congener are recorded for the first time. The two Daphnia species from North America, D. ambigua and D. parvula, still inhabit the lake. In 1995 the seasonal distribution and sexual periods were investigated. Most of the cladoceran species are monocyclic, three are dicyclic. 17 Ostracoda typical for naturallakes in that region, could be found

Observations of Tropospheric and Stratospheric Bromine Monoxide from Satellite : Analysis of Satellite Data derived from GOME for 1996-2001

Column densities of bromine monoxide have been derived from satellite borne Global Ozone Monitoring Experiment measurements for the time period from 1996 to 2001 on a global scale. This data set has been analyzed under various aspects: two methods two achieve a separation of the stratospheric and tropospheric fractions of the total column density have been developed. The method relying on a fixed solar zenith angle interval has been used to study the evolution of stratospheric BrO abundances. As a result, it has been found in accordance with other measurements that the average stratospheric BrO load has increased during the time period under investigation. Time series of tropospheric column density fractions derived with the other method using a reference site, have been successfully compared to in-situ ozone measurements yielding a reasonably good correlation. Differences between both hemispheres in stratospheric as well as tropospheric BrO have been discussed. The northern hemisphere usually shows higher stratospheric and tropospheric column densities. Sources and source strengths of boundary layer BrO have been investigated. Enhanced tropospheric boundary layer BrO is often released in bromine explosion events during polar spring leading to tropospheric ozone holes. The sea-ice and especially frost flowers are the sources for these events. The area covered by ’clouds’ of enhanced BrO column densities in the northern hemisphere has increased by about 10% per year from 1996 to 2001. This indicates that the source strength has increased which is probably due to changes in the Arctic sea-ice cover. The identification of other sources like volcanoes or salt lakes from this satellite borne instrument has not been successful. Strong evidence for a free tropospheric BrO background has been gathered. It has been estimated that about 2pptv BrO are present in the free troposphere with a lower boundary of its lifetime of about four days. Transport events of polar tropospheric Bro towards mid-latitudes and into the free troposphere have been discovered

Satellite Remote Sensing of Atmospheric SO_2: Volcanic Eruptions and Anthropogenic Emissions

In this article, we present satellite data analysis of atmospheric Sulfur Dioxide (SO_2) from volcanic eruptions and anthropogenic activities. Data from Global Ozone Monitoring Experiment (GOME) on board ERS-2 for the years 1996 to 2002 is analyzed using a DOAS based algorithm with the aim of retrieving SO_2 Slant Column Densities (SCDs). Difficulties in the retrieval of SO_2 SCDs due to instrumental effects are investigated in detail and significantly improved. The retrieved SCDs can be used to identify and monitor several volcanic eruptions. A brief introduction of different volcanic eruptions around the globe is presented Also informations about the anthropogenic SO_2 emissions can be easily achieved from the retrieved data set. A time series of anthropogenic SO_2 emissions over Eastern Europe is presented in this study. The time series showed high SO_2 SCDs over Eastern Europe during the winter months. The results demonstrate a high sensitivity of GOME instrument towards SO_2 emissions

Investigating the stretch-shortening cycle fatigue response to a high-intensity stressful phase of training in collegiate men's basketball

IntroductionWhile using force-plate derived measures of vertical jump performance, reflective of stretch-shortening-cycle (SSC) efficiency is common practice in sport science, there is limited evidence as to which tests and measures may be most sensitive toward neuromuscular fatigue. The aim of this study was to explore the SSC fatigue response to a one-week high-intensity fatiguing phase of training in National Collegiate Athletic Association (NCAA) Division-I basketball players.MethodsThe study timeline consisted of three weeks of baseline measures, one week of high-intensity training, and two weeks of follow-up testing. Countermovement jumps (CMJ) and 10-5 hop tests were performed at baseline, as well as at two time-points during, and three time-points following the fatiguing training period, allowing for performance-comparisons with baseline.ResultsCompared to the weekly training sum at baseline, during the high intensity training phase, athletes were exposed to very large increases in selected external load metrics (ES = 1.44–3.16), suggesting that athletes experienced fatigue acutely, as well as potential longer lasting reductions in performance. Vertical jump data suggested that in the CMJ, traditional metrics such as jump height, as well as metrics reflecting kinetic outputs and movement strategies, were sensitive to the stark increase in high-intensity training exposure. The 10-5 hop test suggested a fatigue-induced loss of tolerance to ground impact reflected by performance reductions in metrics related to jump height and reactive strength qualities.DiscussionThese findings emphasize that when monitoring neuromuscular fatigue, variables and assessments may not be looked at individually, but rather as part of a more global monitoring approach