Is a Finnish research that aims to find economical and practical means for providing adequate undergroud resuurses for urban trees growing in normal street environment. Een Fins onderzoek om de economische en pratische uitgangspunten te vinden voor stedelijke bomen in een straat.

1. Viikki
Urban Tree
Laboratorio
Doc. Eero
Nikinmaa,
MSc Anu
Riikonen

2. Aims of the study
• Improve knowledge base of urban tree management
– How quickly tree recover from planting shock? what is suitable irrigation
frequency?
– Do the aereation tubes in soil have positive impact on street tree
development?
– How different surface material used on pavements impact on trees?
• To test the growing properties of load bearing soils
– Can LBS be used to increase root growing space in northern environment
(aereation, water holding capacity, heat capacity & transfer)
– What soil substrate structure is optimal for aeration / water holding in
street conditions
– Can clay/ organic matter guarantee sufficiency of nutrients, when, how
and what fertilizers are needed?
• To charecterise the growing environment of trees on
streets
– Air and soil temperature, light climate, evaporative demand

3. Experimental streets: Normal modern
streets in Helsinki
• Narrow alleys
• Limited growing space
• High mechanical
damage risk
• De-icing

4. Testing different technical solutions
• Aereation pipes
• Concrete and natural
stones
• Different joint
width

5. Load bearing soil
• 3 types
• Load bearing sceleton:
(d 32-64mm) or (d
64-140mm) granite
rocks
• 50 - 55% rocks and 40
- 45% soil + air
(volumetric)
• Soil variation:
– org. matter content
(5-20%) 4.5
– variation in sand content 4
3.5
(pF curves) pF
3
2.5
Soil 1
Soil 2
2
– fertilized (N,P) and non- 1.5
Soil 3
1
fertilized 0.5
0
• Load bearing properties 0 5 10 15 20
Volumetric moisture content %
25
passed laboratory tests

7. Soil nutrient analysis
Experimental street - SOIL ANALYSIS, LOAD BEARING SOILS 2003
Organi
c johto- NH4-
Soil type matter luku pH Ca P K Mg S B Cu Mn Zn NO3-N N Fe Cl Mo Na Cd Cr Ni Al
Kekkilä
1 HkMr vm 15.2 7.3 4000 10 91.1 274 111 1.0 2.9 6.7 1.47 350 4 274 140 0.11 164 <0.05 87 48 9040
1 hkKHt m 14.8 7.3 3790 9.6 88.1 251 102 1.0 2.7 6.8 1.58 320 4 256 120 0.08 168 0.05 19 19 8900
1 HkMr vm 12.8 7.3 4220 10 88.5 253 103 1.0 2.9 6.6 1.29 310 4 241 120 0.07 148 . . . .
1 HkMr vm 13.8 7.3 4500 13 105 268 129 1.0 3.7 7.3 2.58 320 4 298 140 0.11 159 . . . .
1 HkMr vm 13.5 7.3 4190 10 92.6 253 109 0.9 3.2 7.0 2.11 320 6 284 103 0.08 169 . . . .
keskiarvo 14.0 7.3 4140.0 10.5 93.1 259.8 110.8 1.0 3.1 6.9 1.8 324.0 4.4 270.6 124.6 0.1 161.6 0.1 53.0 33.5 8970.0
Yit
2 HtMr rm 10.4 6.6 3910 86 454 286 174 1.2 14.0 17.0 37.20 140 37 1570 75 0.15 171 0.1 49 35 11200
2 HtMr rm 7.0 6.7 3080 110 553 292 83 1.2 7.6 13.0 29.10 42 36 888 73 0.11 209 0.08 130 71 12700
2 HtMr rm 8.3 6.6 3140 86 496 268 94 1.1 9.6 15.0 30.70 84 33 1150 63 0.13 172 . . . .
2 HtMr rm 8.6 6.5 3110 93 551 282 98 1.3 8.3 16.0 26.60 60 44 995 73 0.08 194 . . . .
2 HtMr rm 9.5 6.6 2860 100 561 295 102 1.3 7.2 15.0 27.00 58 48 858 84 0.09 208 . . . .
keskiarvo 8.8 6.6 3220.0 95.0 523.0 284.6 110.2 1.2 9.3 15.2 30.1 76.8 39.6 1092.2 73.6 0.1 190.8 0.1 89.5 53.0 11950.0
Yliop.
3 HkMr m 2.6 8.0 3290 39 188 142 36 0.8 3.8 7.6 5.33 14 3 508 15 0.04 36.2 <0.05 160 74 9080
3 HtMr m 3.1 7.8 3500 42 199 143 44 0.8 3.8 8.1 5.14 15 3 524 19 0.05 38.5 0.05 50 24 8870
3 HtMr m 3.0 7.9 3120 41 180 131 39 0.8 3.5 7.7 4.79 15 2 509 17 0.05 35.9 . . . .
3 HkMr vm 2.4 8.0 3160 41 183 129 35 0.8 3.8 7.6 5.23 12 2 527 14 0.05 35.1 . . . .
3 HtMr m 3.2 8.0 3240 40 192 135 41 0.8 3.5 7.3 4.93 21 2 503 19 0.06 37.4 . . . .
keskiarvo 2.9 7.9 3262.0 40.6 188.4 136.0 39.0 0.8 3.7 7.7 5.1 15.4 2.4 514.2 16.8 0.1 36.6 0.1 105.0 49.0 8975.0
Viljavuusluokkaleimat
Bad
Fairly Bad
Acceptable
Satisfactory
Good
High
Questionably high

8. Monitoring as a method
By monitoring the
growing conditions and
the response of trees to
them we gain rapidly
information of the
causal reasons for tree
preformance in the
urban environment.

9. Set up of monitoring
• 2 Streets
Street I
• 3 Load bearing soil types /
street
Street II
• Alnus glutinosa & Tilia
vulgaris
• ~5-6 trees/treatment
Manual
/street measuring point
Soil types
• 3 intensively monitored Intensive
points/ street (High monitoring
temporal resolution)
• 9 points of manual
monitoring/ street (Spatial
resolution)

10. Monitoring
-Intensive every 10 min
- Manual every 2 - 3 weeks
Growing conditions Tree
• Soil Profiles • Intensive
– Temperature – Sap flux (2 methods )
– Volumetric – Growth
– Gas concentrations • Manual
• Above ground – Gas exchange +
– PAR fysiological measurements
– Air temperature (Fluorosence)
• Meteorological – Nutrients contents
information from nearby – Structure
weather station – Root sampling (sampling
wells 4 distances from
trees)

11. Installation of sensors

12. Temperature
Soil
Gas

13. PAR
Weather
Air Temp

14. Tree
Sap-flux Sap-flux
Heat dissipation Diam. variation

15. Datamanagement
Street 1
G Street 2
Office S
M

16. Manual measurements

17. Street as a growing site
Norkkokuja lpt
Pasteurinkatu, lpt
Irradiation and air temperature 18.7.2004 Min. and Max Temperatures at the two streets 15.-31.8.
norkkokuja, PAR 2004
25 0.2
Pasteurinkatu, PAR 25
0.18
Temperature, degrees C
0.16 20
Temperature, degrees C
20
PAR mmol/m-2 s-1
0.14
0.12 15
15 0.1
10
0.08
0.06 5
10
0.04
0.02 0
15.8.
16.8.
17.8.
18.8.
19.8.
20.8.
22.8.
23.8.
24.8.
25.8.
26.8.
27.8.
28.8.
30.8.
31.8.
21.8.
29.8.
5 0
0:00 3:00 6:00 9:00 12:00 15:00 18:00 21:00
Date
Time
Min. and Max Temperatures at the two streets 15.-31.1. Air temperature at the two streets 15.8.-1.9.2004
2005
25
5
3
Temperature, degrees C
1 20
Air temperature, degrees C
-1
-3
15
-5
-7
-9 10
-11
-13 5
-15 norkkokuja
16.1.
17.1.
18.1.
19.1.
21.1.
22.1.
23.1.
24.1.
25.1.
26.1.
27.1.
28.1.
29.1.
30.1.
31.1.
15.1.
20.1.
pasteurinkatu
0
Date Päivämäärä 19.8. 23.8. 27.8. 31.8.

18. Soil: Annual cycle of temperature, Sufficiency of
water
Soil temperatures, different streets Soil Temperature Pasteur Street, 2003-2004
30
Kekkilä
30
YIT
Soil temperature, degrees C
25 YO/TTKK
25
20
20
Temperature
Norkkokuja 15
15
Pasteurinkatu
10 10
5 5
0 0
26 31 36 41 46 51 4 9 14 19 24 29 34 39 44 49 26 28 30 32 34 36 38 40 42 44 46 48 50 52 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50
Week # Week nro
Volumetric Water content: Norkkostreet 2003-2004 Volumetric water content: Pasteur street 2003-2004
10 cm depth 30 cm depth
100
100
Proportion of pore volume
Proportion of pore volume
75
75
50
50
25 25
0 0
26 30 34 38 42 46 50 2 6 10 14 18 22 26 30 34 38 42 46 50 26 30 34 38 42 46 50 2 6 10 14 18 22 26 30 34 38 42 46 50
Week # Week #

19. Surface pavement material
Concrete stone
Granite”dice”

20. Impact of pavement on soil gas
concentrations ?
CO2 concentrations under different pavement types, both streets 2004
25000
20000
CO2 conc. ppm
15000
10000
5000
0
10 30 60 10 30 60 10 30 60 10 30 60
granite concrete granite concrete
pasteur norkko

21. Permeability to precipitation
Soil moisture content development july 2004
0.500
Volumetric water content %
0.450
0.400
0.350
0.300
0.250
0.200
0.150
0.100
0.050 10 cm
30 cm
0.000
1.7. 4.7. 7.7. 10.7. 13.7. 16.7. 19.7. 22.7. 25.7. 28.7. 31.7.

22. Volumetric water content: Pasteur street 2003-2004
Too much water
30 cm depth
100
Proportion of pore volume 75
50
25
can be a problem!
0
26 30 34 38 42 46 50 2 6 10 14 18 22 26 30 34 38 42 46 50
Week #
CO2 different streets 2004 Soil Co2 and max photosynthesis, Pasteur street july-04
50000 4.5
norkkokuja 4
40000 pasteurinkatu
Pn and soil CO2 %
3.5
versokuja 3
30000
2.5 max.fotos.
20000
2 Hiilid.
1.5
10000 1
0.5
0 0
7.5. 31.5. 21.6. 12.7. 2.8. 16.8. 6.9. 27.9. 18.10. 16.11. 2.12. p2 p5 p8 p12 p15
-10000
Tree
Methane, different streets, 2004 Soil Co2 and max photosynthesis, Pasteur street august-
norkkokuja
pasteurinkatu 04
1000
versokuja
9
8
Pn and soil CO2 %
100
7
6
5 Pn
10
4 Hiilid.
3
2
1
1
0
p2 p5 p8 p12 p15
0.1
7.5. 31.5. 21.6. 16.8. 6.9. 27.9. 18.10. 16.11. 2.12. Tree

23. Aereation pipes are beneficial!
Significance of aereation on different soils CO2 content 2004 in aereated and non-aerated soils
8000
8000
6000 ilmastointi -10
6000
CO2 content ppm
ilmastointi -30
ilmastointi -60
ei ilmastoitu
CO2 ppm
4000 ei ilmastointia -10
ilmastoitu 4000
ei ilmastointia -30
ei ilmastointia -60
2000
2000
0 0
alusta 1 alusta 2 alusta 3 7.5. 31.5. 21.6. 12.7. 2.8. 16.8. 6.9. 27.9. 18.10. 16.11.

24. Soil organic matter reflects on gas
concentrations!
Soil Temperature vs. CO2, Norkko street Soil Temperature vs. CO2, Pasteur street
55000
alusta 1 55000 alusta 1
alusta 2 alusta 2
alusta 3 alusta 3
Expon. (alusta 1) Expon. (alusta 1)
45000 Expon. (alusta 2) Expon. (alusta 2)
45000 Expon. (alusta 3) y = 5547.9e0.0678x
Expon. (alusta 3)
R2 = 0.231
35000
35000
y = 2666.1e0.0893x
y = 439.25e 0.1791x R2 = 0.5521
CO2 content, ppm
R2 = 0.5887
CO2 content ppm
25000 25000
15000 15000
y = 690.43e0.0909x
y = 704.66e0.0892x
R2 = 0.6058
R2 = 0.6335
5000 5000
y = 521.22e0.0721x
R2 = 0.5882
-5000 -5000
0 5 10 15 20 25 0 5 10 15 20 25 30 35
Soil temperature, degrees C Soil Tem perature, degrees C

25. Variation in factors influencing
photosynthetic production
Max photosynthetic rate, different times and different soils. 2004 Stomatal conductance, different soils and times of the year, 2004
16 450
14 400
350
12
300
GS, mikromolm2s-1
10
n1 250 n1
Pn
8 n2 n2
n3 200 n3
6
150
4
100
2 50
0 0
June July August June July August
Pasteurinkatu 2005
O2 content and fluorosence 0.88
June13
0.86
July13
0.85 230000
0.84 August24
220000
O2, ppm
0.82
0.8 210000
Fv/Fm
200000 0.80
Fv/Fm
0.75 190000 0.78
180000
0.76
0.7 170000
0.74
160000
0.65 150000 0.72
5 8 12 15 0.70
1 2 3 4 5 6 8 12 15
Tre e Tree No.

26. Differences in Photosynthetic
production
Net assimilation vs. internal CO2 in Norkkokuja, August 2005
Net assimilation vs. internal CO2 in Pasteurinkatu, August 2005
500
500
400
400
1
1.2
internal CO2, ppm
Internal CO2, ppm
2
300 1.4
300 4
2.2
2.5 5
200 3.2 200 7
3.4 8
10
100 100
0 0
0 5 10 15 20 25 0 2 4 6 8 10 12 14
Net assim ilation µm ol/m 2/s Net assimilation µnol/m2/s
Net assimilation and light, Norkkokuja, August 2005 Net assimilation and light, Pasteurinkatu, August 2005
25 14
12
20
10
net assimilation µmol/m2/s
net assimilation µmol/m2/s
1
15 1.2
8 2
1.4 4
2.2 6 5
10
2.5 7
3.2 4 8
5 3.4 10
2
0
0
1500 600 300 150 75 0 1500 600 300 150 75 0
-2
-5
light, µm ol/m 2/s
light, µmol/m2/s

27. 12
.7
12 . 2
.7 0 0
.2 3
13 0 0 0:
0.135
0.140
0.145
0.150
0.155
0.160
0.165
0.170
.7 3 00 0:
0.000000
0.000100
0.000200
0.000300
0.000400
0.000500
0.000600
0.000700
0.000800
13 .2 12 15
.7 0 0 : 00 12
.2 3 :1
14 0 0 0: 5
00
.7 3 0:
14 . 2 12 15
.7 0 :0
.2 03 0 12
:1
15 0 0 0: 5
.7 3 00 0:
15 .2 12 15
.7 0 0 : 00 12
.2 3 :1
16 0 0 0: 5
.7 3 00 0:
16 .2 12 15
.7 0 0 :00 12
.2 3 :1
17 0 0 0: 5
00
.7 3 0:
17 . 2 12 15
.7 0 :0
. 2 03 0 12
:1
18 0 0 0: 5
.7 3 00 0:
18 .2 12 15
.7 0 0 : 00 12
.2 3 :1
19 0 0 0: 5
.7 3 00 0:
19 .2 12 15
.7 0 0 :00 12
.2 3 :1
20 0 0 0: 5
.7 3 00 0:
20 . 2 12 15
.7 0 0 :00 12
.2 3 :1
21 0 0 0: 5
.7 3 00 0:
21 .2 12 15
.7 0 0 : 00 12
.2 3 :1
22 0 0 0: 5
.7 3 00 0:
22 .2 12 15
.7 0 0 : 00 12
.2 3 :1
23 0 0 0: 5
.7 3 00 0:
23 . 2 12 15
.7 0 0 :00 12
.2 3 :1
24 0 0 0: 5
time
time
.7 3 00 0:
24 .2 12 15
.7 0 0 : 00 12
.2 3 :1
5
25 0 0 0:
.7 3 00 0:
15
Volumetric moisture content
25 . 2 12
.7 0 0 :00 12
Light and canopy conductance july 2003
.2 3 :1
5
26 0 0 0:
.7 3 00 0:
15
26 . 2 12
.7 0 0 :00 12
.2 3 :1
5
27 0 0 0:
.7 3 00 0:
15
27 .2 12
.7 0 0 : 00 12
.2 3 :1
5
28 0 0 0:
.7 3 00 0:
28 . 2 12 15
.7 0 0 :0 12
.2 3 0 :1
29 0 0 0: 5
.7 3 00 0:
29 . 2 12 15
.7 0 0 :00 12
.2 3 :1
5
30 0 0 0:
.7 3 00 0:
15
30 .2 12
.7 0 0 : 00 12
.2 3 :1
5
31 0 0 0:
.7 3 00 0:
15
31 .2 12
.7 0 0 :00 12
.2 3 :1
5
light and soil (example 2003)
0 0:
1. 0 0
8. 3 1 0 0:
15
1. 20 2:
8. 0 00 12
:1
Canopy conductance is linked to
20 3 0 5
0 :0
3 0:
1 0 15
2:
00 12
:1
5
0:
15
0
100
200
300
400
500
600
700
800
900

28. Growth differences
Shoot growth in different parts of crown, Tilia, 2004 Shoot growth in different parts of crown, Alnus, 2004
160
Upper crown 300
Upper Crown
Middle crown
Middle Crown
Av. shoot length, cm
120
Av. shoot length, cm
200
80
100
40
0 0
1 2 4 5 7 8 3 4 2 6 2 4
S1 S2 S3 S1 S2 S3

29. Conclusions
• Irrigation after plantation was sufficiient
• Loosely positioned granite ”dices” allow air
penetration, tight granite rock considerably less
• Aeration pipes improve situation
• Surplus water produced adverse conditions, draught
problem not yet observed. Aereation of pores more
critical than water holding capacity in the souther
boreal city of Helsinki?Climate change scenarios
suggest increasing storm water loads!
• Excees organic matter a risk factor, rapid
decomposition eats O2 + soil properties change
• As O2 dropped below 18% (>2% CO2), tree physiology
changed