SSPI-CT-2003-502158

REBECCA

Relationships between ecological and chemical status of surface waters

Specific Targeted Research or Innovation Project

Policy-oriented research

Final activity report

Period covered: from 1.12.2003 to 31.5.2007Date of preparation:13.7.2007

Start date of project: 1.12.2003Duration: 42 months

Seppo Rekolainen

Finnish Environment InstituteVersion 01

1.Project execution

REBECCA

Relationships between ecological and chemical status of surface waters

Contract no.: SSPI-CT-2003-502158

The strategic objective of the REBECCA proposal has been to provide relevant scientific support for the implementation of the Water Framework Directive (WFD). The two specific aims of the project are, firstly, to establish links between ecological status of surface waters and physico-chemical quality elements and pressures from different sources, and, secondly, to develop and validate tools that member states can use in the process of classification, in the design of their monitoring programs, and in the design of measures in accordance with the requirements of the WFD.

The REBECCA Consortium included 19 contractors:

Finnish Environment Institute / SYKE / Finland
Joint Research Centre / JRC / EC
Norwegian Institute for Water Research / NIVA / Norway
National Environmental Research Institute / NERI / Denmark
DHI Water & Environment / DHI / Denmark
WL | Delft Hydraulics / WL|Delft / The Netherlands
Centre for Ecology and Hydrology / NERC/CEH / The United Kingdom
Centre National du Machinisme Agricole, du Génie Rural, des Eaux et des Forêts / Cemagref / France
Water Research Institute / IRSA / Italy
Swedish Environmental Research Institute / IVL / Sweden
TrinityCollegeDublin / TCD / Ireland
Slovak Hydrometeorological Institute / SHMI / SlovakRepublic
Instituto Nacional de Investigação Agrária e das Pescas / IPIMAR / Portugal
University of Antwerp / UA / Belgium
Danube Delta National Institute / DDNI / Romania
Norwegian Institute for Nature Research / NINA / Norway
Institute for Inland Water Management and Waste Water Treatment / RIZA / The Netherlands
TallinnTechnicalUniversity / TTU / Estonia
Sveriges lantbruksuniversitet / SLU / Sweden

The project started with a comprehensive literature review, whose aim was to assess the state-of-the-art in relation to the project objectives, and, based on the literature view, to analyse the most important knowledge gaps in this field (deliverables D3, D4 and D6). Based on that information the other , water category-based work packages (WP3,4 and 5) redefined and detailed their plans. Simultaneously with the literature review, these work packages started surveying and collecting available chemical and biological data for analysing the relationships and assessing the potential ecological thresholds, which could be utilized in boundary setting for different water quality classes.

The REBECCA project collected existing data owned by REBECCA partners but also from data providers outside the consortium. By contacting external data providers we succeeded to have data sets with improved geographical (and also temporal) coverage. The data sets include chemical and biological data from thousands of sampling sites in European lakes rivers and coastal waters. A big challenge was to assure the data quality, due to the lack of harmonised sampling and analysing methods as well as lack of harmonised taxonomic resolution, the data originating from different countries and institutes/universities was heterogeneous. In spite of a big attempt, data heterogeneity remained as one source of uncertainty in our results.

These data sets were then used to assess the following issues:

  • to investigate the sensitivity of single species, other taxonomic groups, multi-metric indices against different pressures and chemical indicators
  • to test the response the existing biological indicators (described in earlier literature) against pressures using the REBECCA data, and adjust these relationships, if necessary
  • to develop new biological indicators having a better response, and indicators for pressures not referred to in earlier literature
  • to assess reference conditions (in lakes)
  • to evaluate, if ecological thresholds (points of no return) can be found across the pressure gradients
  • to develop new tools to be used in ecological classification

We investigated relationships between the following pressures and biological quality elements:

Phyto-plankton / Macro-
phytes / Benthic
diatoms / Macro-
invertebrates / Fish
Lakes
Eutrophication / √ / √ / √ / √
Acidification / √ / √
Hydromorphology / √
Toxic pressures / √
Rivers
Organic loading / √
Eutrophication / √ / √
Acidification / √
Hydromorphology / √
Toxic pressures / √
Coastal waters
Eutrophication / √ / √
Toxic pressures / √

The results of these analyses are collected in numerous deliverables (D7, D8, D9, D11, D12,D13,D14,D15,D16,D17 and D20), all available at the project Toolbox ( >public document store). Based on these deliverables 14 scientific papers are published and 45papers have been submitted to scientific journals. In addition to those reports, the relationships were validated in case studies by Work package 6. validation results are given in deliverables D5 and D18.

Only a few examples of our results are shown below, more comprehensive view can be obtained from the deliverables (and scientific articles).

In lakes most promising indicators for eutrophication are taxonomic phytoplankton groups. The proportion of cyanophytes increase with increasing pressure (see Fig.1, pressure gradient expressed as chlorophyll a concentration), whilst the proportion of chrysophytes decrease. The proportion of pinnate diatoms increase earlier compared to cyanophytes, but show a decrease in very eutrophic lakes. The increase of cyanophytes are not linear, suggesting that at certain pressure level there is a


threshold, above which the undesired consequences increase rapidly, and restoration is probably more difficult.

Fig. 1. Different phytoplankton groups as a function of chlorophyll a concentration in large clear water lakes in northern Europe.

A relatively good response for eutrophication in rivers showed the benthic diatoms. They take up nutrient directly from the water column, they have shorter generation time compared to macrophytes and they are not as dependent on water retention times as phytoplankton. Trophic Diatom Index(TDI) correlated positively with inorganic nutrient concentrations (see Fig. 2)

Fig. 2. Trophic Diatom Index (TDI) as a function of phosphate, ammonium and nitrate concentration in rivers in several European countries. The blue line is linear regression and red lines represent the 90%ile and 10%ile values.

Generally the relationships between any pressures and any biological indicators were found to be weaker in rivers compared to e.g. lakes. This is due to the fact that more often rivers than lakes are subject to many pressures simultaneously. As a results, when investigating an indicator supposed to be sensitive to a single pressure, a large amount of variability remained unexplained. This calls for indicators for combined pressures which were also studied by the REBECCA Work Package for rivers.

Integrated indicators, in addition to single metrics, were also studies by the Work Package for Coastal waters. One of the approach used was based on Ecosystem Network Analysis, which is based on carbon stocks and flows through the biotic food web. Some of the indicators produced by Ecosystem network Analysis (e.g. Internal Ascendancy, Internal Capacity and Redundancy) were strongly correlated to pressure indicators, such as total nitrogen concentrations (see Fig. 3). This indicates that eutrophic systems have less capacity to counteract pressures and thus having a lower resilience.

Fig. 3. relationship between total nitrogen concentration and Internal Capacity (based on Ecosystem Network Analysis) in Danish coastal waters.

Results of integrated indicator studies show that they may give a good insight to the ecosystem functioning, and may be helpful for selecting single indicators and thus being valuable supporting tools for the implementation of the Water Framework Directive. However, for practical tools they are still premature, and need more research.

Since REBECCA has been a policy support research (supporting the Community water policies, particularly the implementation of the Water Framework Directive), much attention has been paid to organise continuous information flow between the project and end-users of its results. At the Community level the most important link has been between REBECCA and one of the WFD Common Implementation Strategy groups, namely the ECOSTAT working group. REBECCA progress and results have been presented in every ECOSTAT meeting since autumn 2003 until spring 2007, usually 2-3 times per year. In addition to that REBECCA scientists have been working together ECOSTAT Geographical Intercalibration Groups to provide them information in order to set the ecological class boundaries for surface waters.

At national level, all REBECCA partners have been providing information for water authorities and policy makers for planning the ecological classification and developing WFD compliant monitoring programmes.

REBECCA organised three end-user conferences, first in Italy, second in the Netherlands. The Final Conference of the REBECCA project was organised in May 2007 in OsloNorway, with more than 90 participants, of which about 50% were end-users both from European and national level. The Conference programme was designed to present project results, but also how these results can be used in practice, in the implementation of the WFD. The abstracts of the Conference were published, and this publication is also the Deliverable D19.

Of scientific point of view REBECCA groups have prepared close to 60 scientific manuscripts submitted to scientific journals. At the time of writing this report (July 13, 2007) 14 of these papers have been published.

2.Dissemination and use

The results and new knowledge produced by the REBECCA project has been utilized when implementing the ecological classification of surface waters compliant with the Water Framework Directive. Most useful the results have been, when defining the reference conditions and class boundaries. In addition to the Community level boundary setting protocol, the results have been utilized by water authorities and policy makers in Member States when planning their ecological classification systems and monitoring schemes.

All REBECCA results are publicly available through the deliverables downloadable at the project web-site: >public document store.

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