Carbon assimilation and phytoplankton growth rates across the trophic spectrum: an application of the chlorophyll labelling technique
AbstractThe chlorophyll labelling technique has been acknowledged to be a useful method for measuring phytoplankton growth rates while avoiding some of the problems involved in calculating growth rates derived from the 14C fixation rates. The results presented here are of experiments comparing phytoplankton growth rates during the summer season in three subalpine Italian lakes: Lago Maggiore, the second largest lake in Italy, and two smaller lakes, Lake Mergozzo and Lake Varese, both included in the Lago Maggiore drainage basin. The three lakes have different morphometric, physico-chemical and biological features. The first goal was to compare two different methods of estimating phytoplankton growth rates starting from 14C assimilation. The second goal of our experiments was to test the hypothesis that growth rates can be quite different across the trophic spectrum, due to the ecophysiological and morphological features of the phytoplankton assemblages. In particular, algal cell size should decrease from eutrophic to oligotrophic systems and growth rates should follow the opposite trend, as they are inversely scaled to the cell size. Two basic conclusions can be drawn. The first is that, in spite of some drawbacks still affecting the use of the chlorophyll labelling technique, this appears to be one of the most promising methods for estimating the growth rates of phytoplankton in situ. The second conclusion is that this method, coupled with information on some algal morphological parameters, can provide useful indications about the functional properties of phytoplankton assemblages living in diverse lacustrine environments.
- Abstract views: 1902
- PDF: 478
PAGEPress has chosen to apply the Creative Commons Attribution NonCommercial 4.0 International License (CC BY-NC 4.0) to all manuscripts to be published.
An Open Access Publication is one that meets the following two conditions:
- the author(s) and copyright holder(s) grant(s) to all users a free, irrevocable, worldwide, perpetual right of access to, and a license to copy, use, distribute, transmit and display the work publicly and to make and distribute derivative works, in any digital medium for any responsible purpose, subject to proper attribution of authorship, as well as the right to make small numbers of printed copies for their personal use.
- a complete version of the work and all supplemental materials, including a copy of the permission as stated above, in a suitable standard electronic format is deposited immediately upon initial publication in at least one online repository that is supported by an academic institution, scholarly society, government agency, or other well-established organization that seeks to enable open access, unrestricted distribution, interoperability, and long-term archiving.
Authors who publish with this journal agree to the following terms:
- Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
- Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work.