Influence of moderate phosphate addition on nitrogen retention in an acidic boreal lake

Authors: Kaste, Øyvind; Lyche-Solheim, Anne

Source: Canadian Journal of Fisheries and Aquatic Sciences, Volume 62, Number 2, February 2005 , pp. 312-321(10)

Buy & download fulltext article:

Price: $41.66 plus tax (Refund Policy)

Abstract:

Inorganic phosphorus (P) fertilizer was added to a small, acidic lake in southernmost Norway to test the potential of this technique to increase the retention of total inorganic nitrogen (TIN) and thereby mitigate the effects of elevated leaching of atmospherically derived N. The experiment was conducted over 4 years (1 pretreatment year followed by 3 years with weekly P additions during the growing season). To avoid any undesirable eutrophication effects, the total P concentration was increased from 4–5 µg P·L^–1 to a moderate level of 10–12 µg P·L^–1. Compared with the pretreatment year, the P additions increased the average TIN retention in the experimental lake by nearly 70% (from 53 to 88 mmol·m^–2·year^–1) during three growing seasons. However, when considering that the reference lake experienced a 55% decrease in TIN retention during the same period, the increase might have been even larger. This underlines the role of P (both natural and anthropogenic) as an important regulator of N retention in upland lake districts that in large parts of southernmost Norway contribute significantly to the N loading on coastal marine areas.

Nous avons ajouté un engrais à base de phosphore (P) inorganique à un petit lac acide du l'extrême sud de la Norvège afin de vérifier le potentiel de cette technique pour augmenter la rétention d'azote inorganique total (TIN) et ainsi mitiger les effets du lessivage accru de N d'origine atmosphérique. L'expérience a duré 4 ans, dont une année antérieure au traitement et trois années pendant lesquelles nous avons ajouté du P toutes les semaines durant la saison de croissance. Afin d'éviter les effets indésirables de l'eutrophisation, nous avons rehaussé la concentration totale de P de 4–5 µg P·L^–1 à une concentration modérée de 10–12 µg P·L^–1. Par comparaison à l'année qui a précédé le traitement, les additions de P ont accru la rétention moyenne de TIN dans le lac expérimental par près de 70 % (de 53–88 mmol·m^–2·an^–1) durant les trois saisons de croissance. Cependant, si l'on tient compte du fait que le lac témoin a subi un déclin de 55 % de la rétention durant la même période, l'accroissement est sans doute plus élevé. Ces résultats soulignent le rôle de P (tant naturel que d'origine anthropique) comme important agent régulateur de la rétention de N dans les lacs des terres hautes qui, dans de grandes régions de l'extrême sud de la Norvège, contribuent de façon significative à l'enrichissement en N des zones côtières marines. [Traduit par la Rédaction]

Document Type: Research article

Publication date: 2005-02-01

More about this publication?

Published continuously since 1901 (under various titles), this monthly journal is the primary publishing vehicle for the multidisciplinary field of aquatic sciences. It publishes perspectives (syntheses, critiques, and re-evaluations), discussions (comments and replies), articles, and rapid communications, relating to current research on cells, organisms, populations, ecosystems, or processes that affect aquatic systems. The journal seeks to amplify, modify, question, or redirect accumulated knowledge in the field of fisheries and aquatic science. Occasional supplements are dedicated to single topics or to proceedings of international symposia.
Information for Authors
Submit a Paper
Subscribe to this Title
Terms & Conditions
Sample Issue
Reprints & Permissions
ingentaconnect is not responsible for the content or availability of external websites

Influence of moderate phosphate addition on nitrogen retention in an acidic boreal lake

Buy & download fulltext article:

Tools

Key

Text size:

Useful pages