Post on 27-Mar-2015
U N I V E R S I T Y O F A A R H U S
Danish Environmental Research InstituteDepartment of Freshwater Ecology
Brian KronvangEEA Workshop 11-12 September
2008
Brian KronvangNational Environmental Research Institute, Dept. Freshwater Ecology, University of Aarhus, Silkeborg, DenmarkBKR@DMU.DK
(WP5)NutrientRetention
in Catchments&
Applicability ofQuatification
Tools onEuropean
Catchments
Ensemble modelling of diffuse nutrient loads and sources in EUROHARP catchments:Uncertainty in applying different models and the problem with retention
U N I V E R S I T Y O F A A R H U S
Danish Environmental Research InstituteDepartment of Freshwater Ecology
Brian KronvangEEA Workshop 11-12 September
2008
No ‘European best model’ was nominated by the EUROHARP project (2001-2006) but we learned a lot about models and the EUROHARP Toolbox is a potential ‘money saver tool’ for catchment managers
U N I V E R S I T Y O F A A R H U S
Danish Environmental Research InstituteDepartment of Freshwater Ecology
Brian KronvangEEA Workshop 11-12 September
2008
Conclusions and recommendations regarding nutrient emissions Net nutrient loads should always be quantified using
monitoring/modelled results – the net load is the most accurate estimate as shown in EH.
Gross nutrient emissions from background or non-anthropogenic sources should be quantified independently using monitoring data or models.
Nutrient retention in surface waters should be quantified independently using model estimates at water body or river basin scale (EUROHARP NUTRET tool).
EUROHARP has shown that ensemble modelling is a possible way forward to ensure that an estimate of the uncertainty involved in especially nutrient load partitioning can be given.
Application of more than one model will be useful in the future emission reportings as e.g. one simple pan-European method (statistical model), one load apportionment method and one country specific method (source oriented).
U N I V E R S I T Y O F A A R H U S
Danish Environmental Research InstituteDepartment of Freshwater Ecology
Brian KronvangEEA Workshop 11-12 September
2008
Continued Agricultural emissions should always be reported using three
indicators:1. Nutrient surplus2. Leaching from root zone (1 m) (gross emission to groundwater
and surface water).3. Gross emission to surface water – edge of surface waters HYDROLOGICAL DATA IS CRUCIAL BEFORE EVERYTHING ELSE. OSPAR HARP-NUT has developed several guidelines concerning
nutrient losses also an updated guideline 6 on diffuse nutrient losses and guideline 9 on nutrient retention both based on EUROHARP results is to be prepared by Denmark.
EUROHARP has created a tool box to assist catchment managers in chosing the best model(s) for a given river basin.
U N I V E R S I T Y O F A A R H U S
Danish Environmental Research InstituteDepartment of Freshwater Ecology
Brian KronvangEEA Workshop 11-12 September
2008
Nutrients Point
Sources
Nutrient Retention
NutrientsDiffuse Sources
Ecology of water body types
Nutrients ReferenceConditions
WFD sets new standards and requirements for calculation of nutrient sources, emissions and retention in catchments with the purpose of achieving a concentration in surface waters below the level required for obtaining a good ecological quality
U N I V E R S I T Y O F A A R H U S
Danish Environmental Research InstituteDepartment of Freshwater Ecology
Brian KronvangEEA Workshop 11-12 September
2008
Background concentrations of nitrate-N in Danish surface waters – large regional differences
U N I V E R S I T Y O F A A R H U S
Danish Environmental Research InstituteDepartment of Freshwater Ecology
Brian KronvangEEA Workshop 11-12 September
2008
Nutrient losses from fields to surface waters – the problem of retention
Surplus
Leaching
Root
Zone
Surface runoff
Subsurface emission
subsurface retention (b)
surface water retention
(c)
Point sources, background, atm. deposition
wetland retention (d)
Catchment export
Total retention = a+b+c+d+e
root zone retention (a)
buffer zone retention (e)
U N I V E R S I T Y O F A A R H U S
Danish Environmental Research InstituteDepartment of Freshwater Ecology
Brian KronvangEEA Workshop 11-12 September
2008
Estimated Nitrogen retention in groundwater and surface waters for different Danish catchments used for WFD River Basin
Management plans
U N I V E R S I T Y O F A A R H U S
Danish Environmental Research InstituteDepartment of Freshwater Ecology
Brian KronvangEEA Workshop 11-12 September
2008
Daily simulations of flow
and solute concentrations
Annual predictions based on
export coefficient approach
Process oriented(deterministic)
Data oriented
(empirical)
High
Low
Level of complexity
Model typeMethods differ profoundly in their complexity, level of process representation and data requirements
SA NOPOLU REALTA
NL-CAT SWAT
NLES-CAT MONERIS EVENFLOWTRK
EUROHARP model tools
U N I V E R S I T Y O F A A R H U S
Danish Environmental Research InstituteDepartment of Freshwater Ecology
Brian KronvangEEA Workshop 11-12 September
2008
Nutrient emissions – the EUROHARP definitions
U N I V E R S I T Y O F A A R H U S
Danish Environmental Research InstituteDepartment of Freshwater Ecology
Brian KronvangEEA Workshop 11-12 September
2008
Location of the EUROHARP river catchments and diffuse gross N-losses to surface waters
U N I V E R S I T Y O F A A R H U S
Danish Environmental Research InstituteDepartment of Freshwater Ecology
Brian KronvangEEA Workshop 11-12 September
2008
Large differences in the bias involved when modelling net N export from European catchments
U N I V E R S I T Y O F A A R H U S
Danish Environmental Research InstituteDepartment of Freshwater Ecology
Brian KronvangEEA Workshop 11-12 September
2008
• The mean deviation between the P-loads calculated by linear interpolation or by the OSPAR method is ~22%.
0.0001
0.0010
0.0100
0.1000
1.0000
10.0000
0.0001 0.0010 0.0100 0.1000 1.0000 10.0000
specific P load linear interpolation (kg/(ha·a))
spe
cific
P lo
ad
OS
PA
R (
kg/(
ha
·a))
• More than 1/3 of the deviation between the model results for P-loads are due the uncer-tainty of the “observed” P-load
0.0001
0.0010
0.0100
0.1000
1.0000
10.0000
0.0001 0.0010 0.0100 0.1000 1.0000 10.0000
specific P load linear interpolation (kg/(ha·a))
spe
cific
P lo
ad
OS
PA
R (
kg/(
ha
·a))
• Higher deviations occur also for Southern European catchments.
• Precision of loads depends on substance, observation frequency and catchment size.
U N I V E R S I T Y O F A A R H U S
Danish Environmental Research InstituteDepartment of Freshwater Ecology
Brian KronvangEEA Workshop 11-12 September
2008
U N I V E R S I T Y O F A A R H U S
Danish Environmental Research InstituteDepartment of Freshwater Ecology
Brian KronvangEEA Workshop 11-12 September
2008
U N I V E R S I T Y O F A A R H U S
Danish Environmental Research InstituteDepartment of Freshwater Ecology
Brian KronvangEEA Workshop 11-12 September
2008
Mean deviation when modelling nitrogen (N=66) and phosphorus (N=50) in 17 EUROHARP catchments
Mean deviation N P
Net load (export from catchment): 27% 41%
Gross loss from agricultural land: 37% 67%
Gross loss from other diffuse sources:67% 75%
U N I V E R S I T Y O F A A R H U S
Danish Environmental Research InstituteDepartment of Freshwater Ecology
Brian KronvangEEA Workshop 11-12 September
2008
Nutrient retention in surface waters was the factor experiencing the largest variation between models.
U N I V E R S I T Y O F A A R H U S
Danish Environmental Research InstituteDepartment of Freshwater Ecology
Brian KronvangEEA Workshop 11-12 September
2008
EUROHARP Nutrient Retention Software - NUTRET
Offer nutrient retention calculations in different Tiers
Tier 1: Simple - Tier 5: Advanced
U N I V E R S I T Y O F A A R H U S
Danish Environmental Research InstituteDepartment of Freshwater Ecology
Brian KronvangEEA Workshop 11-12 September
2008
In future more emphasis has to be drawn on delivering nutrient modelling results from modellers to managers with some measure of the uncertainty involved
0
20
40
60
80
100
Catchments
Spe
cific
N lo
ss fr
om
agric
ultu
ral l
and
(kg
N/h
a)
U N I V E R S I T Y O F A A R H U S
Danish Environmental Research InstituteDepartment of Freshwater Ecology
Brian KronvangEEA Workshop 11-12 September
2008
General information about the EUROHARP project, partners and modelled European catchments
Tools and models used in project, search in model capabilities, add new tools
Educational pages related to diffuse pollution from European catchments, guidelines
Policy instruments; European and international, relating to diffuse pollution
Water Framework
Directive