1. Morphology and photosynthesis of Larix sibirica needle in Ural region
Zagirova Svetlana
Institute Biology
Komi SC URB RAS

2. Afforested areas in Komi Republic: 1- spruce, 2- pine, 3- fir, 4- larch, 5- cedar, 6- birch, 7- aspen, 8- others

3. The investigations were carried out in western mountainside of the Northern and Sub-Polar Ural (Pechora-Ilych reserve, National park “Yugyd Va”)

4. Larch stands on the Northern and Sub-Polar Ural

5. Larch trees at altitude timber line of Sub-Polar Ural

6. Morphology of larch stand at altitude timber line on the Northern Ural
of plot
Altitude, m a.s.l.
Stand composition, %
Age of trees
Average value of
Number of trees/ 1 he
height, m
diameter, cm 1
623
90 Larix
10 Betula
In total
61-135
32-109
6.5
3.4 20
6.9
144
200
344 2
550
80 Larix
20 Betula
Single Abies
78-110
40-100 -*
6.6
4.5
3.8
20.9
10.2
9.0
456
556 22
1034 3
540
70 Larix
10 Abies
71-248
43-100
47-137
9.6
4.9
4.3
28.2
10.9 10
133
400
378
911 4
502
60 Abies
20 Larix
Singl Cedar
89-130 -
34-88
41-240
5.1
7.7
5.3
5.7
11.9
28.6
12.5
14.0
1167 78
289
1556
Примечание. * - нет данных

7. The objects of investigation
Methods and instruments
Morphologic structure of larch needles
Light and electronic microscope methods
Structure of photosynthetic tissue and cells in needles
Photosynthetic activity of larch at high altitude on the Ural Mountains
LiCor 6400 gas analiser

8. Shoots and needle of larch
Last annual long shoot
Brachyblasts on the annual shoot and trunk
2 year old annual long shoot (auxiblast)

9. Total biomass of needle(1) and stem(2) at different height of larch tree

10. Variation of 2 year old annual shoot length (1), number of brachyblasts per 1 shoot (2) and number of needle per 1 brachyblast (3) in the crown of larch tree

11. 1
Biomass of needles (1) and stems (2) on the branch from middle part of larch crown 2

12. 2-8 year old larch brachyblasts
Number of needles in brachyblast and length of needle

13. Apex on transverse section of larch brachyblast

15. Partial volume (%) of mesophyll in needles of conifer trees
Transverse section of larch needle
Partial volume (%) of intercellular space in mesophyll

16. Characteristics of chloroplasts in larch needle in July
Spruce
Square of chloroplast transverse section (except for starch granule), mkm2
4.0±1.0
8.5±1.1
Number of :
granum per 1 chloroplast section
22±5
thylakoids per 1 granum
5±2
7±2
thylakoids per q chloroplast section
110
154
thylakoids per 1 mkm chloroplast section 28 18

17. Photosynthesis of larch (1) and spruce (2) on the Northern Ural in July

18. Daytime dynamics of PAR (1) and photosynthesis (2) of larch at altitude tree line of North Ural
Partly cloudy day 1 2
Cloudless hot day

19. Photosynthesis of larch needle and microclimatic date in upper part of forest in the North Ural (2006)
Date
Weather
Photosynthesis, mkmol CO2 m-2 s-1
PAR, mkmol m-2 s-1
Air temperature , °С
Air moisture, %
min
max
4 July
Partly cloudy
1.49
2.56
278
1194 7 14 41 64
8 July
Cloudless
1.44
3.09
282
1834 15 29 27 58
11 July
1.27
3.10
201
1681 23 36 25 57
17 July
2.26
4.20
481
1510 21 31 42 73

20. Variation of photosynthesis of larches
Species
Region
Ph, mkmol СО2 m2 s-1
Authors
L.desidua
Europe 3
Beneck et al., 1981
Moscow region
25 (mg СО2 g-1 h-1)
Малкина, 1995
L. cajanderi
Central Yakutia
6-13
Максимов и др., 2005
L. gmelinii
8-10
Vygodskaya et al., 1997
L. sibirica
Irkutsk region
Суворова и др, 2003
Komi Republic,
extreme north taiga
4-10 (mg СО2 g-1 h-1)
Бобкова , Тужилкина, 199
Archangelscaja obl.., 27
(mg СО2 g-1 h-1)
Коновалов, 2002
North and Subpolar Ural
3-4
Zagirova S. (unpublished)

21. Conclusion:
High photosynthesis of larch on the Ural Mountains is provided for large needle surface of brachyblasts, intercellular space in mesophyll and peculiar properties of chloroplasts in its cells. Efficiency of photosynthesis depends on weather in vegetation season.

22. Thank you for attention!
The investigations were supported by Project of Presidium RAS “Biological diversity of terrestial and water ecosystems of the Polar Ural” in
Thank you for attention!