CYCLES OF MACROPHYTES AND PHYTOPLANKTON IN PUKEPUKE LAGOON FOLLOWING A SEVERE DROUGHT
In: http://www.newzealandecology.org/nzje/free_issues/ProNZES20_13.pdf
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academicJournal
Zugriff:
SUMMARY: A three year survey of the aquatk vegetation of a Ne"". Zealand dune lake is described. Pukepuke Lagoon i5 a shallow (max. depth 85cm.), slightly saline lagoon with 15ha of open water. Its inflows drain intensively fann::l land and are rich in nutrients, especially phosphorus. Dense macrophyte crops characterised the lagoon each spring hut the component species differed each year. After a severe drought which dried most of the lagoon bed in the 1969 ~ 70 summer, V noniea anagallis~aquatiea and Ranuneulus fiuitans \vere the dominant species in 1970; then with normal water levels Chara globularis became dominant throughout 1971, followed by Potamogeton erispus in 1972. Factors that enabled the dominant sp~cies to gain an early competitive advantage are discussed.- Drying of the lagoon bed in 1970 is regarded as the major disrupting feature that initiated the sequence of plant species described. Phyto-p!anktcn crops, estimated frem chlorophyll a pigment, were low during macrophyte growth phases but reached peaks in the summer of 1971-72 and 1972-7:1; the former being respomible for the destruction of Chara. The competitive baJance hetween phytoplankton and macrophytes is a delicate one hut the shallow water of Pukepuke Lagoon tends to favour the macrophytes.
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CYCLES OF MACROPHYTES AND PHYTOPLANKTON IN PUKEPUKE LAGOON FOLLOWING A SEVERE DROUGHT
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Autor/in / Beteiligte Person: | Cjbbs, C. W. ; The Pennsylvania State University CiteSeerX Archives |
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Zeitschrift: | http://www.newzealandecology.org/nzje/free_issues/ProNZES20_13.pdf |
Medientyp: | academicJournal |
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