You are here:Home//Results//Methods database (results)//Assessment system for rivers using diatom phytobenthos

back to overview methods

Diatom index IO [id:]

Method: Assessment system for rivers using diatom phytobenthos [Ocena stanu ekologicznego rzek w oparciu o fitobentos okrzemkowy (Indeks Okrzemkowy IO)]

1. General information

1.01 GIG: Central-Baltic
Relevant intercalibration types: n.a.
1.02 Category: Rivers
1.03 BQE: Benthic Diatoms
1.04 Country: Poland
1.05 Specification:
1.06 Method name: Assessment system for rivers using diatom phytobenthos
1.07 Original name:
Ocena stanu ekologicznego rzek w oparciu o fitobentos okrzemkowy (Indeks Okrzemkowy IO)
1.08 Status: Method is/will be used in Second RBMP (2015)
1.09 Detected pressure(s):
Catchment land use, Eutrophication, General degradation, Pollution by organic matter Pressure-impact-relationship: n.a.
1.10 Internet reference: n.a.
1.11 Pertinent literature of mandatory character: n.a.
1.12 Scientific literature: n.a.
1.13 Method developed by: n.a.
Email of developer:
Institute of developer: n.a.
1.14 Method reported by: Joanna Picinska-Faltynowicz
Email of person reporting the method:
Email of institute reporting the method:
Institute of Meteorology and Water Management, Wroclaw Branch, Department of Ecology
1.15 Comments: none

2. Data acquisition

Field sampling/surveying

2.01 Sampling/Survey guidelines:
Picinska-Faltynowicz, J. & J. Blachuta, 2008. Zasady poboru i opracowania prób fitobentosu okrzemkowego z rzek i jezior. Przewodnik metodyczny. Wersja 2008. Wroclaw.
2.02 Short description:
5-10 replicates scraped from different stones along a transect crossing river's bed constitute a sample
2.03 Method to select the sampling/survey site or area: Expert knowledge
2.04 Sampling/survey device: Scraper
2.05 Specification: none
2.06 Sampled/surveyed habitat:
Specification of sampled habitat: Hard bottom
Sampled habitat: Single habitat(s)
2.07 Sampled/surveyed zones in areas with tidal influence: not relevant
2.08 Sampling/survey month(s):
Mountain and mid-altitude streams: February to April, Lowland streams and rivers: September to November
2.09 Number of sampling/survey occasions (in time) to classify site or area: One occasion per sampling season
2.10 Number of spatial replicates per sampling/survey occasion to classify site or area: 5-10 replicates per sampling occasion
2.11 Total sampled/surveyed area or volume or total sampling duration to classify site or area:

Sample processing

2.12 Minimum size of organisms sampled and processed: n.a.
2.13 Sample treatment:
Organisms of the complete sample are identified.
2.14 Level of taxonomical identification:
Level: Species/species groups
Specification of level of determination: n.a.
2.15 Record of abundance:
Determination of abundance: Relative abundance
Abundance is related to: n.a.
Unit of the record of abundance: n.a.
Other record of abundance: a total of 300-500 diatom valves counted per sample
2.16 Quantification of biomass: n.a.
2.17 Other biological data: none
2.18 Special cases, exceptions, additions: none
2.19 Comments: none

3. Data evaluation


3.01 List of biological metrics:
Diatom Index IO = (ZTI + ZSI + GR)/3; ZTI = 1-(TI x 0.25); ZSI = 1-[(SI-1) x 0.33]; GR = Sum of relative abundance of reference taxa; TI = Trophic Index (Rott et al. 1999); SI = Saprobic Index (Rott et al. 1997); TI and SI are calculated using a weighted formula of Zelinka & Marvan (1961)
3.02 Does the metric selection differ between types of water bodies: No
3.03 Combination rule for multi-metrics: Average metric scores
3.04 From which biological data are the metrics calculated:
List of biological metrics: Data from single sampling/survey occasion in time

Reference conditions

3.05 Scope of reference conditions: Surface water type-specific
3.06 Key source(s) to derive reference conditions:
Scope of reference conditions:
Existing near-natural reference sites, Expert knowledge, Least Disturbed Conditions
3.07 Reference site characterisation:
Number of sites: A total of 30 sites for different abiotic river types
Geographical coverage:
Reference zones in natural and landscape parks in Central Highlands, Carpathians, Central Plains, Baltic Province and Eastern Plains
Location of sites:
Karkonosze, Tatry, Bieszczady, Magurski, Drawienski and Biebrzanski Natural Parks, Chojnicki, Wdzydzki, Suwalski Landscape Parks
Data time period: February - April and September - November 2004-2009
Absence of point pollution sources, sub-basin dominated by natural forests, meadows and wetlands; slight hydromorphological changes have not been taken into account as they do not affect diatom phytobenthos communities
3.08 Reference community description:
Epilithic diatom communities dominated by reference species, i.e. oligo-mesotrophilous and oligosaprobic depending on a stream/river type
3.09 Results expressed as EQR: Yes

Boundary setting

3.10 Setting of ecological status boundaries: n.a.
3.11 Boundary setting procedure: In preparation
3.12 "Good status" community: In preparation


3.13 Consideration of uncertainty: No (to be done)
3.14 Comments: none

back to overview methods

WISER: "Water bodies in Europe: Integrative Systems to assess Ecological status and Recovery"
Online: [date: 2022/01/28]
© 2022 WISER (Contract No. 226273). All rights reserved.