Water Quality

H. Behrendt, M. Grossmann, H. Gömann, U. Mischke, A. Schöll, J. Steidl

GLOWA-ElbeGLOWA Status conference 19 May 2005 Cologne

Linkages of quantification tools for the estimation of costs – ecological state relationships in the surface

waters of the Elbe catchment

Tasks of the Working Package

Results of Phase I

Concept of Phase II

Conclusions

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VH I: Integration und -coordination Integrative Methodological Approach GLOWA-Elbe (IMA)

Regional actors, decision bodies

Frame of Development

VH II: Regionalisation of Global Change

Glo

bal

Ch

ang

eM

ana

gem

ent

leve

l

VH V: Cross conflict field scenario analysis

Management-options

Impact-analysis

Evaluation

VH IV: Conflict field

Surface Water Quality

Nutrient entry

Cost-efficiency analysis

Eco-hydrological Indicators

Socioeconomic Indicators

VH III: Conflict field

Surface Water Availability

Run off regulation

Multi-criteria analysis

Eco-hydrological Indicators

Socioeconomic Indicators

Project advisory board

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Tasks

Development of a system of models,

for scenario calcula-tions of possible changes of nutrient concentrations and ecological state in the Elbe:

• due to climate changes and

Precipitation Temperature

• socio-economic development and

RAUMIS

Connections of people

WWTP technologies

• environmental targets (e.g.WFD)

Ecological state of the water bodies of the Elbe and coastal zone

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Results phase I:

Establishment of a harmonized database for the modeling of nutrient emissions into the total Elbe catchment

Begin of cooperation with Czech institutions (e.g. boundaries of Czech subcatchments, unified soil loss map, tile drained areas, statistical data)

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Estimation of the nutrient emissions into the total Elbe catchment:

• Applicability of the model for areas outside Germany

• Estimation of nutrient emissions for 184 subcatchments in the Elbe

• Model calculations for different time periods in the past

Long term changes of P-concentrations at Zollenspieker

Diffuse P emissionsin the Elbe Basin

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Changes of nutrient emissions due to climate

• Use of precipitation and discharges of WATERGAP 4 for two different climate models

• Depending on the used climate model the N emissions can increase or decrease up to 15%

• Scenario calculations on regional changes of discharge and nitrogen emissions for 2025

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Changes of nutrient emissions due to changes of global climate and regional human activities

The socio-economic changes in the past influenced strongly the nitrogen emissions

The changes due to climate changes are probably low

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Interactions between agricultural activities and nitrogen emissions

Only the introduction of a strong N-tax leads to a substantial reduction of N-emissions from agricultural areas.

The maximum potential for the reduction of N-emissions is about 1/3 compared to 1999

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GOWA-Elbe Phase II

Ecological consequences

Human activities

Climate changes

Costs

Find solutions which have large ecological effects with a optimum of costs

Nutrient loads

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Linkage between nutrient loads and ecological state of the river

Classification of phytoplankton in

rivers

Tool for the modeling:

QSIM

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Classes and linkage between phosphorus and phytoplankton in rivers

Classes and linkage between nitrogen/phosphorus and ecological state

of the coastal zone?

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Linkage between human activities and nutrient loads

Activities in urban area

Agricultural activities

Measures for sewers / WWTP / connection of

peoplecentral versus decentral

RAUMIS / SWIM

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N taxe

Catchment 1 Catchment 2

Bufferstrips

Increasing costs

Mea

sure

x

Reduction of N / P load (t/a)

Mea

sure

Y

Costs (€/a)

Degree of application

Cost – efficient combination of measure?

- Scenarios

- Bio-economic model

Min! (Costs * Degree of application)

random condition N / P reduction targetsl

Costs and effects

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Conclusions

• A harmonized database for the total Elbe for the diffuse sources of nutrient entries exists. An enlargement for point sources is needed for the calculation of individual measures.

• Average changes of climate are compared to human activities of minor importance for the nutrient emissions. But what is the sensitivity of biological indicators and which changes can be expected for extreme changes?

• Beside the emissions the retention processes determine the nutrient concentrations and ecological state of the water bodies. Measures for changes of retention have to be studied especially for lakes and wetlands.

• The combination of the model MONERIS with the models RAUMIS and SWIM is realised for the study of agricultural and climate influences on the nutrient emissions and loads.

• This set of models have to be enlarged by bio-economic and ecosystem models to estimate the costs of different ecological states of the water bodies

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Thank You

For Your Attention!

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