Report of St. Petersburg Team
O.G. Chertov, M.A. Nadporozhskaya E.V. Abakumov
Biological Research Institute St. Petersburg State University
2005
INTAS 01-0633 SILVICS
Introduction A close cooperation with the Pushchino
and Fraunhofer teams Development of a theoretical
background for the SOM model Incorporation of a new experimental
data into the models Formulation a new version of ROMUL
model Test the models for different spatial
scales
The laboratory experiments Impact of biochemical parameters of
plant debris on the rate of their decomposition
Impact of the disposition of decomposing matter (pure or in mixture with different soil material) to specify difference of above-ground and below-ground litter decomposition and patterns of decomposition in organic layers
Specification of nitrogen mineralisation in dependence on SOM and soil properties
The field works include:
Experiments on decomposition of forest litter fall of different quality in the forest
A study of SOM accumulationin a process of primary soil formation
Theoretical analysis of the decomposition process
0
20
40
60
80
100
1 t
%
Sugars and proteins
Celluloses
Lignin
Biochemical concept
0
20
40
60
80
100
0 t
Re
sid
ua
l m
ass
, %
Litter
Humified litter
Humus
Successional discrete concept
Continuum of litter quality loss and humification
40
60
80
100
1
Litter Humus t
Re
sid
ua
l m
ass
, %
Ågren Bosatta concept
Model of SOM and N dynamics ROMUL
The model is based on a classical concept of “humus type” (Humusform)
Experimental base for the model compilation is published and author’s data on organic debris decomposition in controlled conditions
The rate of litter and SOM humification and mineralisation is dependent on quality of litter, soil temperature and moisture, and some soil physical and chemical parameters
There is a specification of rate variables for above and below ground litter cohorts
The model calculates the dynamics of organic matter and nitrogen during the decomposition with gross CO2 and available N evaluation
The model was evaluated against the long-term experimental data
The model is in use as a soil compartment in three forest ecosystem models
Flow chart of ROMUL model
Li - Undecomposedlitter on soil surface
F.i - complex of humussubstances with
undecomposed debris(humified organic layer)
Lju -
undecomposedlitter in mineral
topsoil
F ju - complex of humus
substances withundecomposed debris in
mineral topsoil (“labil humus”)
H - humusbonded withclay minerals
Lju0 -
Belowgroundlitter fall
ki1L
ki2L
ki3L
K j4L K j
5S
K6
K j1S
K j3S
K j2S K j
4S
K j5S
Soil surface
Li0 -
Abovegroundlitter fall
Elaboration of a new ROMUL version
A large set of experimental data for SOM decomposition allows for a revision of ROMUL model
The kinetic coefficients of litter and SOM mineralisation were re-calculated using Bleasdale function and a special program (A.S. Komarov and M.A. Nadporozhskaya)
This allowed to specify the mineralisation rate in two sub horizons of forest floor (F and H) and a peat
A structure and test program of a new version of ROMUL model was compiled and preliminary tested
Calculation of kinetic coefficients of organic debris mineralisation and humification
Stage of fast decomposition reflects a mineralisation of fresh organic debris
Stage of slow decomposition represents a mineralisation of humified organic debris - not the material with increased concentration of lignin only
The function of Bleasdale was used for approximation of experimental curves:y = (a + bt) - 1/c or y = (a + bt)1/c
Flow chart of a new version of ROMUL model
Green – previous version, red – new components
L in A0 or poor decomposed peat
F in A0 or mean decomposed peat
New:Sub-horizon H in forest floor (A0)or well decomposed peat
Mineral topsoil
L_above
F_aboveCHS above
L_belowLabile
humus1
F_belowCHSbelowLabile
humus2
K1
K2
K3
H_below
0.3024*K2
K4*(1-f(CN))
K4*f(CN)
K1bK2b
K4b
L0b
K5a
K5bK3b
H_above
K6
K8
K8
L0a
The use of forest ecosystem model EFIMOD for research and practical implementation at forest stand, local and regional levels
Recently, the idea on the necessity to have a cascade of
forest ecosystem models with a different spatial resolution
was dominated in the terrestrial ecosystem modelling
Now there are technical opportunities allowing for a use
of one basic model type at any spatial levels without the
loss of information obtained at the lower levels
Some results of and prospects for the implementation of
one basic model type to cover different spatial scales in
forest ecosystem modelling were investigated
Methods and Material
Standard EFIMOD simulations of a single stand growth and soil changes were performed for the model use at different scales:
Individual tree growth Stand level: effects
of environmental changes; thinning regimes
Local (landscape) level: silvicultural regimes in forest enterprise (case studies)
Regional level: soil carbon dynamics for a large forest area
Individual tree growth
0
2
4
6
8
10
12
14
16
18
20
0 5 10 15 20 25 30 35 40 45
Time, years
Tre
e h
eig
ht,
m
Trajectories of individual tree growth on 25-m transect in a modelled Norway spruce stand
Map of individual trees’disposition on the modelled plot
Hierarchy of spatial scales for the application of a stand level
model Stand level: Parameters of individual trees’ growthStand/soil parameters in detailNo generalised parameters for forest area Local/landscape level:
Optionally parameters of individual tree growthStand/soil parameters in detailsGeneralised parameters of any format for forest area
Regional level:No parameters of individual tree growth
Optionally stand/soil parameters in full detailsGeneralised parameters of any format for forest area
The results of EFIMOD runs at different scales shows that
The application of one basic stand-level forest model for different spatial scales has positive prospects for its further development
At local and regional levels, this approach was used by Chumachenko et al. (2003: ForRus), Ho et al. (1999: LANDIS), Garman (2004), Kurz & Apps (1999: CBM-CFS2) and Nabuurs et al. (2003: EFISCEN)
The approach can be an additional methodological option that will be more effective for the practical implementation of the forest modelling for the realisation of the concept of Sustainable Forest Management
Case study I and II: Application of the EFIMOD-Pro for the
analysis of carbon balance at different silvicultural regimes in forests of Central
European Russia
Collaboration with Project’s Teams
Close co-operation with Pushchino and Fraunhofer teams
Participation in the Case Study Participation in the interpretation
and presentation of the results of geovisualisation and Exploratory Spatial Data Analysis (ESDA) for Case Study
Links to other projects
EU INTAS Project 01 512 Podzol St. Petersburg State University
Project ‘Changes of Soils and Soil Cover under Anthropogenic Factors’
Russian Federal Science and Technology Program “Global Climate Changes and Carbon Cycle”, part 14 “Soil as a source of greenhouse gases”
Publications for the period 2002-2005
International journalsPublished 4Submitted 3
Proceedings and national journalsPublished 7Submitted 3
Abstracts to conferences 19
21 presentations at international and national scientific meetings for the period May 2002 - February 2005
Pushkin, SPB (3) Gent(1)DSS Vienna (3), Uni Hohenheim (1) Trippstadt Forest Station (1) Pushchino (3),Kazan (2),Quebec (1)ForMod Vienna (3)ECEM 04 (2)
Acknowledgements
The participants of SPBU team
acknowledge
colleagues from other teams of the
Project,
the Administration of the Biological
Institute,
the Department of Soil Science and Soil
Ecology of St. Petersburg State
University and
the Dokuchaev Soil Museum for their
active
collaboration and valuable help
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