You are here:Home//Results//Methods database (results)//Assessement Method for Ecological Status of the Water Body (rivers) based on Phytobenthos

back to overview methods


Method: Assessement Method for Ecological Status of the Water Body (rivers) based on Phytobenthos [Metoda de evaluare a starii ecologice a corpurilor de apa (rauri) pe baza fitobentosului]

1. General information

1.01 GIG: Eastern Continental
1.02 Category: Rivers
1.03 BQE: Benthic Diatoms
1.04 Country: Romania
1.05 Specification:
1.06 Method name:
Assessement Method for Ecological Status of the Water Body (rivers) based on Phytobenthos
1.07 Original name:
Metoda de evaluare a starii ecologice a corpurilor de apa (rauri) pe baza fitobentosului
1.08 Status: Method is/will be used in Second RBMP (2015)
1.09 Detected pressure(s):
Eutrophication, General degradation, Pollution by organic matter, Riparian habitat alteration Specification of pressure-impact-relationship:
1543 series data from 382 monitoring stations; 3 years at least. Correlation coefficient ranging from 0.17 to 0.6 for different relationship between: number of diatom taxa and N-NO3, diatoms abundance and SiO2, saprobic index and P-tot, diatoms abundance and COD-Cr etc.
Yes, with quantitative data (e.g. against range of sites reflecting continuous gradient of pressure).
1.10 Internet reference:
1.11 Pertinent literature of mandatory character:
Romanian study 2009-2010: Studiu privind elaborarea obiectivelor de mediu si al sistemului de clasificare al starii apelor de suprafataîn conformitate cu prevederile Directivei Cadru pentru Apa.
1.12 Scientific literature:
1.13 Method developed by: Stefan Miron
Email of developer:
Institute of developer: Romanian Water Authority, Prut Directorate
1.14 Method reported by: Gabriel Chiriac
Email of person reporting the method:
Email of institute reporting the method: Romanian Water Authority, Apele Romane

2. Data acquisition

Field sampling/surveying

2.01 Sampling/Survey guidelines: SR EN 13946/2003, SR EN 14407/2004
2.02 Short description:
Multi-habitat scheme: Coverage of all representative micro-habitats. Sometimes 5 stones. Cleaning (acid/peroxide digestion); Permanent slides; Identification
2.03 Method to select the sampling/survey site or area: Random sampling/surveying
2.04 Sampling/survey device: Brush, Spoon, Scraper
Other phytobenthos sampling device: PVC Pipe, Capillary tube, Pipettes
2.05 Specification: Scraper, spoon, brush, PVC pipe, capillary tube, pipettes
2.06 Sampled/surveyed habitat:
Sampled habitat: All available habitats per site (Multi-habitat)
2.07 Sampled/surveyed zones in areas with tidal influence: not relevant
2.08 Sampling/survey month(s): (March) April / May; July / August; September / October (November)
2.09 Number of sampling/survey occasions (in time) to classify site or area: 2-3 times / year. Seasonal.
2.10 Number of spatial replicates per sampling/survey occasion to classify site or area: 5-20 replicates
2.11 Total sampled/surveyed area or volume or total sampling duration to classify site or area:
Minimum 5 cm2 per replicate

Sample processing

2.12 Minimum size of organisms sampled and processed: All benthic diatoms
2.13 Sample treatment:
Organisms of the complete sample are identified.
2.14 Level of taxonomical identification:
Level: Species/species groups
2.15 Record of abundance:
Determination of abundance: Individual counts
Abundance is related to: Area
Unit of the record of abundance: Number of individuals per sample - IBD method
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:
Number of taxa, numerical abundance of diatoms, numerical abundance of centric diatoms, Shannon-Wiener diversity index, IBD (biological diatom index), Saprobic Index
3.02 Does the metric selection differ between types of water bodies: No
3.03 Combination rule for multi-metrics: Average metric scores; Worst quality class
3.04 From which biological data are the metrics calculated:
List of biological metrics:
Aggregated data from multiple sampling/survey occasions in time
Aggregated data from multiple spatial replicates

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:
Least disturbed conditions, Expert knowledge, Existing near-natural reference sites
3.07 Reference site characterisation:
Number of sites: 382 monitoring sites
Geographical coverage:
Different ecoregions and geographical areas: high mountains, hills, plains, littoral etc.
Location of sites: National Protected Areas
Data time period: 2004-2009
The absence of major human impact.
Minimal anthropogenic pressures (agriculture, land use, population density). Natural vegetation in the catchment area.
Longitudinal continuity and lateral connectivity.
3.08 Reference community description:
High diversity, absence of invasive species, ratio among algal groups, absence of bacterial tufts and coats
3.09 Results expressed as EQR: Yes

Boundary setting

3.10 Setting of ecological status boundaries:
High-good boundary derived from metric variability at near-natural reference sites
3.11 Boundary setting procedure:
25th percentiles of all data have been chosen for high/good boundary. 50th percentiles of all data have been chosen for good/moderate boundary. 75th percentiles of all data have been chosen for moderate/poor boundary. 90th percentiles of all data have been chosen for poor/bad boundary.
3.12 "Good status" community:
Good-high diversity, ratio among algal groups, absence of bacterial tufts and coats. High probability of having >50% cover of sensitive species and no more than 50% cover of tolerant species. The highly sensitive species are still present (10-50% cover) and highly tolerant (undesirable) species would be <20% cover.


3.13 Consideration of uncertainty: No (to be done)
Specification of uncertainty consideration: n.a.
3.14 Comments: none

back to overview methods

WISER: "Water bodies in Europe: Integrative Systems to assess Ecological status and Recovery"
Online: [date: 2019/05/24]
© 2019 WISER (Contract No. 226273). All rights reserved.