Viesturs Jansons Professor, Head of Department of Environmental Engineering and Water Management. Latvia University of Agriculture, e-mail viesturs.jansons@llu.lv

1. Monitoring of the Agricultural Run-off in
Latvia (1994-2005)
Viesturs Jansons
Professor, Head of Department of
Environmental Engineering and
Water Management. Latvia
University of Agriculture,
e-mail viesturs.jansons@llu.lv
Water balance:
Precipitation 700 mm
Evapotranspiration 450 mm
Run-off 250 mm
Latvia - 6.4 million ha
Population - 2.4 million
Agricultural land - 2.4 million ha
Drainage - 1.6 million ha

2. Agriculture and water quality
Baltic Sea
HELCOM political goal (1988) to decrease agricultural pollution by 50% has
not been reached in most of countries.
HELCOM PLC-4 (2000)
79 % is input from agriculure
78% is input
from
agriculture

3. Monitoring network in Latvia
3 non-point source pollution monitoring stations (sites)
Bērze (368 ha, intensive farming,
cereals and sugar beets, arable
land 80-90 %.). Established 1968 /
1994
Vienziemīte (592 ha, low input
agriculture, agr. land 79 %, arable
land 4-5 %). Established 1948 /1994
Mellupīte (960 ha, average
intensity, arable land 60-70 %).
Established 1995.
3 point source pollution monitoring points (large animal
farms):
Vecauce (1000-2000 pigs, 30 ha slurry application field)
Ogre (farm closed in 1992, heavily polluted territory)
Bauska (8000 pigs, 50 ha slurry dumping field)
3 non-point source pollution points (small catchments):
Auce (53 ha, intensive farming, cereals)
Skriveri (890 ha, average intensity of farming)
Bauska (750 ha, intensive farming, cereals, sugar beats)

4. Monitoring scale (non point pollution)
Mellupite station, one plot 0,12 ha
5 treatments x 3 = 15 plots
Soil, plant, nutrient and water relationships
could be studied in the plot level, and nutrient
leaching from soil with a different application
of mineral or organic fertilisers for various
crops might be examined in detail.
Mellupite station,
12 ha
Vienziemite station,
67 ha
Berze station,
77 ha
Nutrient losses from arable land might be
measured at a field level. Field scale run-off
represents are integrated effect of farming
practice, crop rotation, application of
fertilisers etc. on the water quality.
Mellupite station, 960 ha
Vienziemite station, 592 ha
Berze station, 368 ha
The integrated influence on nutrient run-off of variations
in farming practices, erosion, soil and topography within
the small catchment might be studied in a better way than
in the field scale. In that scale emission rates (loads) that
can contribute to the nutrient enrichment of surface water
ecosystem can be examined.

5. Mellupīte monitoring station (BEAROP Project 1994-2000)
H. Structure – Crump
weir
Tipping buckets for
plot measurements
Small catchment
station with inlets from
plots and hydraulic
structure.
Weather station
Surface run-off
plot

6. Hydraulic structure – V – shape Crump weir
Berze station constructed 2006 – BSRP (WB and
GEF project)

7. Drainage field station
Both surface and
drainage run-off

8. Monitoring technology
Continuous recording of data from
sensors (every 3 min) with data loggers,
automatical flow proportional water
sampling in all measurement points
Measurement
equipment - YSI
data loggers,
powered from solar
panels. GSM data
transfer with
mobile phone from
stations to
university PC

9. Ground water monitoring
Shallow ground water
monitoring since 2005:
10 wells in 3 monitoring
sites are equipped with YSI
mini data loggers (to
, water
level sensors)
Depth of the wells is 4-6
m and 14-18 m
(unconfined and confined
aquifers)
Water sampling (zonde)
every 3 months

10. Monitoring results 1994-2005
Average concentrations of the nitrogen in run-off
0,00
2,00
4,00
6,00
8,00
10,00
12,00
14,00
Plots
(unfertilized)
Plots
(normal)
Plots(high)
Plots(solid
manure)
Plots(slurry)
Drainage
field
Small
catchment
Drainage
field
Small
catchment
Drainage
field
Small
catchment
NO3/N Ntot
mg/l
Mellupite monitoring site
Berze
monitoring
site
Vienziemite
monitoring
site
11.3 mg/l N/NO3 (Nitrate Directicve)

11. Monitoring results 1994-2005
Trends of the nitrogen concentrations in run-off
Vienziemīte catchment
0,00
0,50
1,00
1,50
2,00
2,50
3,00
3,50
4,00
4,50
N / NO3 mg/l
Mellupīte catchment
0,00
2,00
4,00
6,00
8,00
10,00
12,00
14,00
16,00
N / NO3 mg/l Bērze catchment
0,00
2,00
4,00
6,00
8,00
10,00
12,00
14,00
16,00
18,00
20,00
N / NO3
mg/l
1994 2005
11.3 mg/l N/NO3
(Nitrate Directicve)

12. Monitoring results 1994-2005
Pollution load (Ntot) from agricultural land in Latvia
6,0
8,9
15,3
0
5
10
15
20
25
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
Average
Ntot kg/ha year
Vienziemite catchment Mellupite catchment Berze catchment
Load = Concentration x discharge
Wastewater
One population
equivalent
13 g of Ntot
day-1
or
4,7 kg Ntot
year-1

13. Measures to decrease pollution?
EU Nitrate directive - Action plans in VZ
Rural development plan - Agro-environmental
Schemes
• Green land 50% (30%)
• Nutrient balances in farms
• Buffer zones
• Manure storage

14. Buffer Zones

15. Buffer Zones
Results of the Latvia Agro-environmental Scheme, 2005
AE measure
“Buffer
Zones”
Payment,
Euro/m
No of the
applications
Length of the
(m)
“Buffer Zones”
Drainage
channels, 4 m
0.102 160 165 493
Arable land,
fields, 4 m
0.18 57 102 274
Water
reservoirs,
rivers, 10 m
0.256
126 62 583
Total 343 33035

16. Improvement of Manure Storage in the VZ.
Results of Latvia Agro-environmental Scheme,
2005
Size of
farm
Number of
farms
Total
volume,
m3
Solid
manure,
m3
Slurry, m3
1-10 AU 9 2040 1640 400
10-49 AU 35 28500 19900 6800
50-99AU 7 11600 3200 8400
100-250 AU 8 31200 22900 8300
>250 AU 3 15900 1800 14100
62 89240 49440 38000
BSRP project - 3 storages (1 under construction). Investments 50-100%.