ZIB

Hits per page

hits 1 - 2 | 2 hits

Sorting

Electronic Resource

Long-term response of a shallow, moderately flushed lake to reduced external phosphorus and nitrogen loading (2005)

KÖHLER, J. ; HILT, S. ; ADRIAN, R. ; [et al.]

Oxford, UK : Blackwell Science Ltd

Freshwater biology 50 (2005), S. 0

add to mindlist on the mindlist

Details

ISSN: 1365-2427

Source: Blackwell Publishing Journal Backfiles 1879-2005

Topics: Biology

Notes: 1. The responses of nutrient concentrations, plankton, macrophytes and macrozoobenthos to a reduction in external nutrient loading and to contemporary climatic change were studied in the shallow, moderately flushed Lake Müggelsee (Berlin, Germany). Weekly to biweekly data from 1979 to 2003 were compared with less frequently collected historical data.2. A reduction of more than 50% in both total phosphorus (TP) and total nitrogen (TN) loading from the hypertrophic (1979–90) to the eutrophic period (1997–2003) was followed by an immediate decline in TN concentrations in the lake. TP concentrations only declined during winter and spring. During summer, phosphorus (P) release from the sediments was favoured by a drastic reduction in nitrate import. Therefore, Müggelsee acted as a net P source for 6 years after the external load reduction despite a mean water retention time of only 0.1–0.16 years.3. Because of the likely limitation by P in spring and nitrogen (N) in summer, phytoplankton biovolume declined immediately after nutrient loading was reduced. The formerly dominant cyanobacteria (Oscillatoriales) Limnothrix redekei and Planktothrix agardhii disappeared, but the mean biovolume of the N2-fixing species Aphanizomenon flos-aquae remained constant.4. The abundance of Daphnia spp. in summer decreased by half, while that of cyclopoid copepod species increased. Abundances of benthic macroinvertebrates (mainly chironomids) decreased by about 80%. A resource control of both phytoplankton and zooplankton is indicated by significant positive correlations between nutrient concentrations and phytoplankton biovolume and between phytoplankton and zooplankton biomass.5. Water transparency in spring increased after nutrient reduction and resulted in re-colonisation of the lake by Potamogeton pectinatus. However, this process was severely hampered by periphyton shading and grazing by waterfowl and fish.6. Water temperatures in Müggelsee have increased in winter, early spring and summer since 1979. The earlier development of the phytoplankton spring bloom was associated with shorter periods with ice cover, while direct temperature effects were responsible for the earlier development of the daphnid maximum in spring.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1111/j.1365-2427.2005.01430.x

Permalink

Library	Location	Call Number	Volume/Issue/Year	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

Electronic Resource

Die dringliche Pankreatektomie bei der akuten Pankreatitis (1971)

Hollender, L. F. ; Gillet, M. ; Köhler, J. J.

Springer

Langenbeck's archives of surgery 328 (1971), S. 314-327

add to mindlist on the mindlist

Details

ISSN: 1435-2451

Keywords: Pancreatitis ; Surgery ; Acute Pancreatitis ; Pancreatectomy ; Acute Pancreatitis-Complications

Source: Springer Online Journal Archives 1860-2000

Topics: Medicine

Description / Table of Contents: Zusammenfassung Das Studium von 17 Fällen, bei denen eine Frühpankreatektomie durchgeführt wurde, bestimmt wie folgt unser therapeutisches Verhalten: Bei der akuten postoperativen Pankreatitis sind wir angesichts des schwerwiegenden Krankheitsverlaufes überzeugt von der Notwendigkeit einer frühzeitig durchzuführenden ausgedehnten Pankreatektomie. Bei der akuten primären Pankreatitis sind wir etwas zurückhaltender, da selbst bei offener Bauchhöhle das Schicksal gewisser Pankreaspartien nicht mit Sicherheit vorhergesagt werden kann. Dennoch bestimmen unsere im Vergleich mit den Literaturangaben günstigen persönlichen Erfahrungen mit der Pankreatektomie unser aktives chirurgisches Vorgehen bei der akuten nekrotisierenden hämorrhagischen Pankreatitis.

Notes: Summary The study of 17 cases of acute pancreatitis, in whom early total or subtotal pancreatic resection were performed, has led to the following therapeutic principles: the serious nature of acute post-operative pancreatitis has convinced us of the necessity for early intervention and as extensive a resection as possible; 5 out of 6 patients were cured in this way. In case of acute primary pancreatitis we are more conservative since even at laparotomy it is difficult to foresee the fate of all parts of the pancreas. Nevertheless our relatively favorable results led us to intervene surgically if the signs and symptoms of pancreatitis do not show any improvement after 8 to 12 h. If acute, diffuse pancreatitis affects the whole organ subtotal pancreatectomy is performed. If the head of the pancreas is affected we confine ourselves to the removal of necroses. Duodenopancreatectomy does not seem justified in the acute phase; only 1 out of 3 patients survived this procedure.