A method to choose water depths for zooplankton samples in lakes

Research output: Contribution to journalArticlepeer-review

76 Downloads (Pure)

Abstract

As methods in the literature to sample zooplankton in lakes mostly offered general guidance on the sample depths, a new one was developed. Using the principle of volume-weighted sampling of the lake volume and an empirical function for the hypsometric curve, formulae for the volumes and areas of five equal sections of the lake were derived, which were then used to calculate section mean depths. Vertical net hauls taken at the mean depths are combined using a relation between their mean depths to produce one unbiased composite sample of the zooplankton. While generic formulae were derived, starting values for the depths that divide the lake volume into five equal sections are needed in order to apply the method, which then optimizes the depths; the method is implemented in a spreadsheet. The method was applied to four hypothetical lakes of maximum depth 12 m that cover a wide variation of lake form and how the sample depths vary with form was described; as lake form becomes more convex, the sample depths decrease, reflecting that more of the lake volume is at shallower depth. The method was used to estimate the whole-lake abundance of zooplankton in 51 lakes and no practical difficulties were encountered. It can be used in lakes up to a few tens of km 2 in area.

Original languageEnglish
Pages (from-to)836-845
Number of pages10
JournalLimnology and Oceanography: Methods
Volume19
Issue number12
Early online date23 Nov 2021
DOIs
Publication statusPublished online - 23 Nov 2021

Bibliographical note

Funding Information:
We would like to thank the INTERREG IVA Programme of the European Union's European Regional Development Fund, managed by the Special European Union Programmes Body, for funding this work. It formed part of the cross‐border DOLMANT project (reference number 002862). We would also like to thank an anonymous reviewer and an associate editor for valuable comments that improved the clarity of the text. All views expressed here are those of the authors, and do not necessarily reflect those of the organizations with which they are affiliated.

Funding Information:
We would like to thank the INTERREG IVA Programme of the European Union's European Regional Development Fund, managed by the Special European Union Programmes Body, for funding this work. It formed part of the cross-border DOLMANT project (reference number 002862). We would also like to thank an anonymous reviewer and an associate editor for valuable comments that improved the clarity of the text. All views expressed here are those of the authors, and do not necessarily reflect those of the organizations with which they are affiliated.

Publisher Copyright:
© 2021 Crown copyright. Limnology and Oceanography: Methods published by Wiley Periodicals LLC on behalf of Association for the Sciences of Limnology and Oceanography. This article is published with the permission of the Controller of HMSO and the Queen's Printer for Scotland.

Keywords

  • New Methods
  • Ocean Engineering

Fingerprint

Dive into the research topics of 'A method to choose water depths for zooplankton samples in lakes'. Together they form a unique fingerprint.

Cite this