Table 4 General description of the quality of the data for different taxa using different methods.
From: Finnish inventory data of underwater marine biodiversity
Taxa | Quantitative | Presence-absence | Presence only | Notes |
|---|---|---|---|---|
Algae | Cover estimates available | Reliably identified to species level using diving, snorkelling and aquascope. Video methods can only be used to identify absences for a selected number of large distinct species. | Rake observations are more accurately used to indicate presence only | Video observations devoid of vegetation can be used to indicate absence |
Aquatic plants | Cover estimates available | Reliably identified to species level using diving, snorkelling and aquascope. Video methods can only be used to identify absences for a selected number of large distinct species. | Rake observations are more accurately used to indicate presence only as they don’t capture all species with equal efficiency and some not at all. | Video observations devoid of vegetation can be used to indicate absence. |
Terrestrial plants | Cover estimates available | Terrestrial vegetation observed on shore is not observed as consistently as aquatic vegetation. These can be identified from the list described in Table 3. | No systematically collected information available | |
Mosses | Cover estimates available | Reliably identified to using diving, snorkelling and aquascope. Video methods can only be used to identify absences for a selected number of large distinct species. | Rake observations are more accurately used to indicate presence only | Video observations devoid of vegetation can be used to indicate absence |
Sessile fauna | Cover estimates available. Ind/m2 from benthic samplers. | Sessile fauna can be reliably identified to species level using Kautsky, diving, snorkelling and aquascope. Using video methods to indicate absence is more prone to uncertainty due to the nature of the method as species can be covered by vegetation | ||
Epifauna | Semiquantitative; number of individuals from captured with associated to Fucus with mesh bags | Fucus bag samples can be used to indicate absences | Epifauna observed using vegetation mapping and video methods should be considered as presence only or at the very least to have imperfect detection. | |
Infauna | Ind/m2 from benthic samplers. | Benthic grab and core samplers can be used to indicate absences | Infauna observed using vegetation mapping and video methods should be considered as presence only or at the very least to have imperfect detection. | |
Fish | Fish observed using vegetation mapping and video methods should be considered as presence only or at the very least to have imperfect detection. | Fish have not been consistently recorded and some projects have not recorded fish at all |
