Improvement of the quality of data on nutrient inputs with focus on transboundary loads

Seppo Knuuttila SYKE The aim of the project “Improvement of the quality of data on nutrient inputs with focus on transboundary loads” was: . to support the assessment of the share of transboundary nutrient loads originating from the Daugava/Western Dvina and Nemunas/ catchments in the total inputs to the , . to support compilation and assessment of nutrient load data (PLC), improve its quality, completeness and consistency, and . to support intercalibration exercises including testing of sampling methodology, and application of common quality assurance methods for collection of data in participating countries (Latvia, and ). Sampling sites of the project in May and November 2013 Total nitrogen, 2nd sampling in 2013

NTOT 3000

2500

2000

1500

µg/l NTOT (µg/l), FI NTOT (µg/l), LT 1000 NTOT (µg/l), BY NTOT (µg/l), LV 500

0 20 Nov 19 Nov 18 Nov 18 Nov 21 Nov 20 Nov 21 Nov 21 Nov 21 Nov River mouth Border Border Border River mouthRiver mouthRiver mouthRiver mouthRiver mouth (LT) (LT/BY) (LT/BY) (LV/BY) (LV) (LV) (LV) (LV) (LV) Nemunas Nemunas Neris Daugava Daugava Barta Venta Lielupe Gauja Total phosphorus, 2nd sampling in 2013

PTOT 160

140

120

100

80

µg/l PTOT (µg/l), FI PTOT (µg/l), LT 60 PTOT (µg/l), BY

40 PTOT (µg/l), LV

20

0 20 Nov 19 Nov 18 Nov 18 Nov 21 Nov 20 Nov 21 Nov 21 Nov 21 Nov River mouth Border Border Border River mouth River mouth River mouth River mouth River mouth (LT) (LT/BY) (LT/BY) (LV/BY) (LV) (LV) (LV) (LV) (LV) Nemunas Nemunas Neris Daugava Daugava Barta Venta Lielupe Gauja nd Dissolved PO4-P, 2 sampling in 2013

PO4-P, dissolved 70

60

50

40

µg/l P PO4 dissolved (µg/l), FI 30 P PO4 dissolved (µg/l), LT P PO4 dissolved (µg/l), BY 20 P PO4 dissolved (µg/l), LV

10

0 20 Nov 19 Nov 18 Nov 18 Nov 21 Nov 20 Nov 21 Nov 21 Nov 21 Nov River Border Border Border River River River River River mouth (LT) (LT/BY) (LT/BY) (LV/BY) mouth (LV) mouth (LV) mouth (LV) mouth (LV) mouth (LV) Nemunas Nemunas Neris Daugava Daugava Barta Venta Lielupe Gauja

Total phosphorus, the Nemunas, river mouth

Tot-P 200 180 160 140

120

100 µg/ 80 60 40 20 0 1990 1995 2000 2005 2010 2015 Total nitrogen, Nemunas river mouth

Tot-N 9000 8000 7000 6000

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µg/l 4000 3000 2000 1000 0 1990 1995 2000 2005 2010 2015 Total phosphorus, Nemunas near LT/BY border

Tot-P 160

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80 µg/l 60

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20

0 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 Total nitrogen, the Nemunas, near LT/BY border

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0 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 Phosphorus Daugava 120 concentrations 100

80

in November 60 µg/l 40 20 0 Nemunas River mouth Border 100 Tot-P PO4-P

80

60 Nemunas-Neris

µg/l 40 100 80 20

60 0 River mouth Border µg/l 40 Tot-P PO4-P 20

0 River mouth Border Tot-P PO4-P Nitrogen concentrations Daugava in November 2000

1500

1000 µg/l

500 Nemunas 0 3000 Tot-N NO3+NO2-N NH4-N 2500 River mouth Belarus border 2000

Nemunas-Neris 1500

µg/l 3000 1000 2500

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0 1500 Tot-N NO3+NO2-N NH4-N µg/l 1000 River mouth Belarus border 500 0 Tot-N NO3+NO2-N NH4-N River mouth Belarus border Tot-P load, Nemunas+Neris, near LT/BY border

Tot-P 1200

1000

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600 t/a

400

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0 LT (1997-2010) BY (2004-11) BNI 2013 Transboundary project 2014 Tot-N load, Nemunas+Neris, near LT/BY border

Tot-N 16500

16000

15500

15000

14500 t/a 14000

13500

13000

12500

12000 LT (1997-2010) BY (dissolved N 2004- BNI 2013 Transboundary project 11) 2014 Tot-P load, Daugava, near LV/BY border

Tot-P 2500

2000

1500

t/v 1000

500

0 BY (2004-11) BNI 2013 (RU+BY->LV) Transboundary project 2014 Tot-N load, Daugava, near LV/BY border

Tot-N 25000

20000

15000

t/a 10000

5000

0 BY (dissolved N 2004-11) BNI 2013 (RU+BY->LV) Transboundary project 2014 Discussion of lessons learned and additional data needs . The Workshop discussed how to deal with quality assurance and quality control (QA/QC) related to transboundary loads and the importance to ensure comparability of analysis results of laboratories in participating countries. Although several countries already have bilateral agreements to share data, there is still room for improved cooperation. . It was noted that in many cases there are available data but that sharing and exchanging data is a challenge that needs to be addressed. The challenge ahead is to consider how all the data can be accessed and made use of by the different countries and for HELCOM purposes

. There was a suggestion that the development of a portal for data exchange between countries would be helpful. It was noted that the new modernized PLC- water database will be able to handle transboundary loads and this will also facilitate access to transboundary input data. . The Workshop suggested that more regular and coordinated monitoring of transboundary inputs should be established to determine retention in transboundary and border rivers and to provide better information as support for follow-up of the BSAP nutrient reduction scheme.