Morphology and photosynthesis of Larix sibirica needle in Ural region

Zagirova SvetlanaInstitute Biology Komi SC URB RAS

Afforested areas in Komi Republic:1- spruce, 2- pine, 3- fir, 4- larch,

5- cedar, 6- birch, 7- aspen, 8- others

The investigations were carried out in western mountainside of the Northern and Sub-Polar Ural (Pechora-Ilych reserve,

National park “Yugyd Va”)

Larch stands on the Northern and Sub-Polar Ural

Larch trees at altitude timber line of Sub-Polar Ural

N of plot

Altitude, m

a.s.l.

Stand composition, %

Age of trees

Average value of Number of trees/ 1 he height,

mdiameter, cm

1 623 90 Larix10 Betula

In total

61-13532-109

6.53.4

206.9

144200344

2 550 80 Larix20 BetulaSingle Abies

In total

78-11040-100-*

6.64.53.8

20.910.29.0

45655622

1034

3 540 70 Larix20 Betula10 Abies

In total

71-24843-10047-137

9.64.94.3

28.210.910

133400378911

4 502 60 Abies 20 Larix20 BetulaSingl Cedar

In total

89-130-34-8841-240

5.17.75.35.7

11.928.612.514.0

116778

28922

1556

Morphology of larch stand at altitude timber line on the Northern Ural

Примечание. * - нет данных

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

2 year old annual long shoot (auxiblast)

Brachyblasts on the annual shoot and trunk

Shoots and needle of larchLast annual long shoot

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

0 2 4 6 8

4

8

12

16

Hei

ght o

f tre

e, m

Fresh biomass, kg

12

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

0 20 40 60 80 100

7

9

11

13

15

3

2

1

0102030405060

1 2 3 4 5 6 7 8 9 10

Age of annual shoot, year

Fres

h bi

omas

s, g

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

0

20

40

60

80

1 2 3 4 5 6 7 8 9 10

Age of annual shoot, year

Nee

dle

biom

ass,

%

12

2-8 year old larch brachyblasts

Number of needles in brachyblast and length of needle

01020304050

2 3 4 5 6 7 8

Age of annual long shoot, year

Number of needle in brachyblast Length of needle, mm

Apex on transverse section of larch brachyblast

Partial volume (%) of mesophyll in needles of conifer trees

Transverse section of larch needle

Partial volume (%) of intercellular space in mesophyll

0

10

20

30

40

50

part

ial v

olum

e,%

Larch Ceder Spruce

Characteristics of chloroplasts in larch needle in July

Characteristic Larch 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 22±5

thylakoids per 1 granum 5±2 7±2

thylakoids per q chloroplast section

110 154

thylakoids per 1 mkm2 chloroplast section

28 18

Chl

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

0,000

0,020

0,040

0,060

0,080

0,100

0 500 1000 1500

PAR, mkmol m2 s-1

Taki

ng o

f CO 2

, mkm

ol g

-1 s

-1

1

2

Daytime dynamics of PAR (1) and photosynthesis (2) of larch at altitude tree line of North Ural

Partly cloudy day

Cloudless hot day

0,00

0,02

0,04

0,06

0,08

0,10

0,12

8:59 9:48 10:36 12:02 12:50 13:38 14:27 15:15

Taki

ng o

f СО

2, m

kmol

g-1

s-1

020040060080010001200140016001800

PAR,

mkm

ol m

-2 s

-1

0

500

1000

1500

2000

25009:

40

9:53

10:0

8

10:2

3

10:3

8

10:5

3

11:0

8

11:2

3

11:3

8

12:3

7

12:5

2

13:0

7

13:2

2

13:3

7

13:5

2

14:0

7

14:2

2

14:3

8

14:5

3

15:0

8

PAR,

mkm

ol m

-1 s

-1

0,000,020,040,060,080,100,120,14

Taki

ng o

f СО

2, m

kmol

g-

1 s-1

1

2

Date Weather Photosynthesis, mkmol CO2 m-2 s-1

PAR, mkmol m-2 s-1

Air temperatu

re , °С

Air moisture,

%

min max min max min max min max4 July Partly

cloudy1.49 2.56 278 1194 7 14 41 64

8 July Cloudless 1.44 3.09 282 1834 15 29 27 5811 July Cloudless 1.27 3.10 201 1681 23 36 25 5717 July Cloudless 2.26 4.20 481 1510 21 31 42 73

Photosynthesis of larch needle and microclimatic date in upper part of forest in the North Ural (2006)

Species Region Ph, mkmol СО2 m2 s-1 Authors

L.desidua Europe 3 Beneck et al., 1981

L.desidua Moscow region 25 (mg СО2 g-1 h-1) Малкина, 1995

L. cajanderi Central Yakutia 6-13 Максимов и др., 2005

L. gmelinii Central Yakutia 8-10 Vygodskaya et al., 1997

L. sibirica Irkutsk region 3 Суворова и др, 2003

L. sibirica Komi Republic,extreme north taiga

4-10 (mg СО2 g-1 h-1) Бобкова , Тужилкина, 199

L. sibirica Archangelscaja obl.., extreme north taiga

27 (mg СО2 g-1 h-1)

Коновалов, 2002

L. sibirica North and Subpolar Ural 3-4 Zagirova S. (unpublished)

Variation of photosynthesis of larches

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.

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 2009-2010