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1. Carbon cycle model, carbon cycle and climatic change joint model

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1-3. Dynamic vegetation model

The organization in charge: Earth frontier research system
Person-in-charge name : Sato Hisashi (ecosystem change prediction area of investigation)
Akihiko Ito (ecosystem change prediction area of investigation)
Kohyama Takashi (ecosystem change prediction area of investigation)
The department of /Hokkaido University graduate school earth environment scientific inquiry
a. Summary

Design of ball vegetation models (DGVM, Dynamic Global Vegetation Model) dynamic [ all ] and code creation were advanced. Although the fundamental design of this model combined the vegetation dynamic state component of LPJ-DGVM with terrestrial carbon cycle model Sim-CYCLE, it incorporated the space structure for a wood clearly further, and performed extension of treating woody plant with an individual base. The process of regeneration of a forest gap and the competing process between trees individuals are exactly expressed by these extension, and it is expected that the carbon balance accompanying a vegetation dynamic state, the speed of the vegetation distribution change accompanying a climate change, etc. can be predicted more correctly than any DGVM built so far. By this time, development of the program code which performs calculation in a part for one wood is completed mostly, and the last check of a code is performed. From now on, the simulation result in all ball grids is due to be obtained even during FY 2004 through process, such as vectorization, parallelization, parameter estimation, and adjustment.

b. Research purpose

Although climate environment specifies the structure and the function of vegetation strongly, the structure and the function of vegetation also have feedback-influence on climate environment (Foley et al.2003). In order to take such a process into climate environmental change prediction, in the earth integrated model KISSME which is furthering development in the 2nd project of symbiosis, it is planning using terrestrial carbon cycle model Sim-CYCLE (Ito and Oikawa 2002) as one constituent factor.

In Sim-CYCLE, the vegetation which it was assumed that the structure of vegetation is horizontally homogeneous and was moreover once materialized in it does not collapse, unless climate conditions are changed sharply. However, the developed forest is a dynamic structure object with which collapse and reproduction are repeated in the wood part unit before and behind 100m2, and, as for such a dynamic state (gap dynamic state), carbon flux change of a forest is specified strongly. Although the photosynthesis quantity of production and the amount of maintenance breathing balance mostly and the carbon balance in vegetation generally changes for about zero plus or minus by a part for the wood which ripened, it is because many of photosynthesis products are used for production of a structure object and it functions as a carbonaceous sink in a part for the wood in the middle of another side and growth (for example, Kira and Shidei 1967).

Moreover, in Sim-CYCLE, it assumes that distribution of a vegetation type is eternal, and 18 sorts of vegetation types are beforehand assigned to each grid of land. However, we are anxious about the potential error in a model output becoming large, so that it will become long, if the period which it is considered for distribution of vegetation to change from 100 years with change of climate conditions in the long time factor of hundreds of years, therefore is simulated becomes long.

Then, in order to be able to treat such a vegetation dynamic process and vegetation type change by the earth integrated model KISSME, it extends to the so-called dynamic-all ball-vegetation model (Dynamic Global Vegetation Model, DGVM) by adopting vegetation dynamic processes, such as death, disturbance, fixing, and competition, to Sim-CYCLE as a function of an environmental condition, and changing distribution of a vegetation type to it based on those results.

c. A research program, a method, a schedule
c.1. Research program

The following elements are added to terrestrial carbon cycle model Sim-CYCLE, and it extends to ball vegetation models dynamic [ all ].
terrestrial vegetation is expressed as vegetable function type (Plant Functional Types, PFT) combination, such as a tropical evergreen broad-leaved tree and a frigid fallen-leaves needle-leaf tree.

Competition between PFT(s) or between individuals is incorporated by defining vegetation dynamic processes, such as death, disturbance, and fixing, as a function of an environmental condition. The model of these dynamic processes is fundamentally obtained from LPJ-DGVM (Sitch et al.2003) which is the existing DGVM.

Furthermore, in this model, the ambitious trial in which treat woody plant with an individual base and the space structure for a wood is treated in detail is performed. The direction of vegetation change and prediction of the period which it takes are expected to be obtained more appropriately by this. Vegetation change is a phenomenon produced mainly as a result of competition between plants, and is because it is the phenomenon produced with an individual base while such competition is strongly specified on local optical conditions.

c.2. Method (basic design of a model)

In this clause, the sign in a parenthesis shows a variable about what begins from a parameter and a small letter about what begins from a capital letter. The table about those definitions is attached to the end of a clause. Moreover, as for these, the parameter and variable identifier in a program correspond.

The data inputted, a parameter
(1) The parameter about a place
    Latitude (Latitude), altitude (Altitude)
(2) Soil parameter
    Soil water-retaining capacity (WHCup) to 300mm below ground, soil water-retaining capacity (WHClow) 300mm or less below ground, the degree (Hyd_cond) of soil permeance, albedo (Albedosoil)
(3) Weather data (one-day interval)
    the temperature (tmpair) in 2m from the ground, and earth surface -- temperature (tmpsfc), soil temperature (tmpsoil10 )10cm below ground, soil temperature (tmpsoil200 )200cm below ground, the degree (p_cloud) of cloud, precipitation (prec), specific humidity (humid), and wind velocity (wind)

Information outputted
(1) Carbon dynamic state
    The carbon cumulative dosage of land, the carbon dioxide rate of absorption by photosynthesis, carbon dioxide discharge speed by breathing and decomposition, carbon dioxide discharge speed by a fire
(2) Water dynamic state
    Soil water content, transpiring speed, an evaporation rate, outflow speed
(3) Radiation income and outgo
    Change of the albedo accompanying transition of vegetation
(4) Information about vegetation
    A scene, the vegetable function type which dominant, the woody plant density, age distribution and size distribution of trees, a leaf area index and its change, the woody plant biomass (a tree crown, a trunk, root) for every individual, the grass plant biomass per unit area (a ground part, underground part), liter cumulative dosage

A vegetable function type and how to search for a scene

In all ball grids, a vegetation dynamic state is treated upwards, and a small number of vegetable function type (Plant functional types, henceforth, PFTs) is made to summarize a land higher plant generally. With Book DGVM, ten kinds of following PFTs(es) were assumed according to the taxonomy of LPJ-DGVM. PFT1 to PFT8 is woody plant, and PFT9 and PFT10 are grass plant.

    1:Tropical broad-leaved evergreen
    2:Tropical broad-leaved raingreen
    3:Temperate needle-leaved evergreen
    4:Temperate broad-leaved evergreen
    5:Temperate broad-leaved summergreen
    6:Boreal needle-leaved evergreen
    7:Boreal needle-leaved summergreen
    8:Boreal broad-leaved summergreen
    9:Temperate herbaceous with C3photosynthesis system
    10:Tropical herbaceous with C4photosynthesis system

The biomass determines the vegetation scene of each calculation grid per the individual density of woody plant PFT who dominant, and unit area of grass plant PFT who dominant. For example, in the division which Tropical broad-leaved raingreen and C4 grass plant are dominant(ing), it is condition of considering it as a "summer green forest" if woody plant's individual density is high, and making it a "desert area" if woody plant's individual density is low, the grass plant biomass is high and "savanna", woody plant's individual density, and the grass plant biomass are low. The judgment standard is due to be acquired from BIOME3 (Haxeltine and Prentice 1996).


Treatment of woody plant

Treating with the individual base, the each object presupposed that it consists of three parts of a tree crown, a trunk, and a root. Each part is expressed by the following variable. In addition, the form of a tree crown and a trunk assumes a pillar and does not treat a form clearly about a root.

Tree crown: The biomass (masscrown), leaf area (la), a diameter (crown_diameter), the depth (crown_depth)
Trunk: The biomass (masstrunc), height (height), the diameter of the sapwood in 1.3m from the ground, and heartwood (dbhsapwood, dbhheartwood)
Root: Biomass (massroot)
In addition to the above-mentioned variable, the each object presupposed that it has storage resources (massstock). In case this moves from a dormant period at a leafing stage, it is resources used for production of a leaf.

Treatment of grass plant

grass plant accepts it originally with a leaf, is constituted, and is expressed by the weight per unit area (gmassleaf, gmassroot), respectively. Moreover, it has storage resources (gmassstock) like woody plant, and is used for production of the leaf at the time of moving from a dormant period at a leafing stage. In addition, in a calculation division, the distribution region of woody plant PFT and grass plant PFT assumes overlapping.

Fixing (in the case of woody plant)

woody plant presupposed that only one individual can be grown in a 1mx1m mesh. the diameter of a tree at breast-height set all new fixing woody plant to 0.01m (all -- sapwood -- it consists of parts), and computed many parameters of woody plant who fills this diameter-of-a-tree-at-breast-height size on the occasion of fixing. In this model, it assumes that a tree crown does not overlap between the woody plant individuals. Therefore, it becomes conditions about the existing trees not only not growing, but the tree crown not overlapping with the mesh to which sapling can newly be fixed with the tree crown of the existing individual, in case sapling is established. In the mesh which can be established, when the precipitation for one year is over the fixed threshold value (Precmin) last year, woody plant is established by fixed probability (P_establish).
Two parameters were given about the standard which determines PFT which can be established, and when the latest climate running mean for 20 years of each grid was settled in these ranges, that it can be established carried out. (1) maximum coldest-month temperature (TCmax) and (2) minimum growth degree day (GDDmin). Each of these values was acquired from LPJ-DGVM.
which fixing is possible -- it can choose from the following three scenarios about PFT being established at what kind of rate. In an actual simulation, the maximum presumption of vegetation change speed and the minimum presumption are obtained more using Scenario 2 and 3, respectively. If these both difference is large, it means that it cannot disregard the effect of the seed diffusion in vegetation change.
Scenario1 (one specific PFT establish): Only one kind of woody PFT specified beforehand is established. For parameter estimation.
Scenario2 (infinite seed dispersal mode): It is not concerned with what kind of woody PFT is distributed now, but all woody PFT that can be established by the environmental condition is established by equally probability. Scenario3 (no seed dispersal mode): Apply Scenario2 to a spin rise. In a subsequent simulation, a fixing ratio is decided in proportion to the biomass for every woody PFT.

Fixing (in the case of grass plant)

grass plant assumes that it always exists in all grids, and does not treat fixing process clearly. Although grass plant consisted of two kinds of PFT(s) and had C3 course and C4 course, respectively, all grass plant assumed that any of the course could be used, and when coldest-month temperature of the previous year became more than 15.5 degrees (standard of LPJ), presupposed that C3 course changes in the case of below C4 course and it.

Water environment

Most water budget modules are the same as that of Sim-CYCLE. A part of rain evaporates in the atmosphere immediately according to the interception effect by crown canopy. And as for it, a part or all of rain that arrived on the ground begins to snow according to temperature conditions, and these are stocked by surface of the earth to a thaw. Therefore, the input of the water in earth surface is two lines, rain and melted snow.
Soil assumes two layers, the 30cm upper layer (litter layer) and the lower layer (mineral matter layer) from 30cm below ground, from 0cm below ground. According to the osmosis speed (Hyd_cond) at which the rain supplied to earth surface was given to soil, a part permeates a lower layer from the upper layer. Finally, it escapes from any of the following four courses to the exterior. the evaporation (from the upper layer) from earth surface, original sucking (from the upper layer and a lower layer), and the dryness (from the upper layer) from earth surface -- and -- flowing (lower layer) .
The maximum water content is given to the upper layer and a lower layer for every grid (WHCup, WHClow), and the value which mixed actual water content with this maximum water content was defined as moisture content (second_per_whcup, ms_per_whclow). The water budget of each grid is decided as a function of this moisture content, the osmosis speed (Hyd_cond) beforehand given for every plot, transpiring speed, and various weather conditions.
At this model, parameter P_root_up defines biomass distribution of each solution perpendicular about PFT. And it was assumed that the soil layer which water absorption produces corresponded to this biomass distribution. That is, when it is defined as 80% of a certain root biomass of PFT being in the upper layer (i. e., P_root_up=0.80), as for this soil moisture content for PFT, (water_status) is given by 0.8xms_per_whcup+0.2xms_per_whclow. running mean for one week or one month was used for each of ms_per_whcupand ms_per_whclowat the time of this calculation. Moreover, the root biomass vertical distribution for every PFT obtained data from Jackson et.al. (1996).

Optical environment and photosynthesis

The amount (par) of photosynthesis effective radiation before going into vegetation is computed at intervals of one day for every grid from the shortwave radiant quantities (radtop) and cloud amount (cloud) in an air outside based on Sim-CYCLE. par by which incidence is carried out to the tree crown of each woody plant individual is computed using par for every grid of the. The degree of opening sky for every individual was first computed about all woody plant (1 time per month). the center of the summit of a tree crown -- the straight line of 256 directions is extended in the shape of radiation toward the whole sky, and it asks for the rate of sunlight attenuation according to the formula of Monsi and Saeki (1953) from light attenuation coefficient (eK) according to the leaf area index (lai) which each of that line passes, and passing woody plant PFT.
Formula
And the average value of the all directions-oriented rate of sunlight attenuation was made into the degree of opening sky of the woody plant's tree crown summit. This assumes tacitly that the sunlight distribution in a celestial sphere is uniform. In addition, it was assumed that eight repetition grids existed so that a calculation grid may be surrounded so that the bias of optical environment might not arise in the end of a calculation grid. Moreover, only the influence of the shade-ed of woody plant who is close within a 30m radius of [ of the degree calculation of opening sky ] an object was made applicable to calculation for mitigation of computational complexity. par by which incidence is carried out to each woody plant is computed by the multiplication of par before going into vegetation, and the degree of opening sky for every vegetation at intervals of one day. (In case of , however this method, like the degree area of high ground, since it is correctly unreproducible, the optical environment of the woody plant individual may be changed from now on in the area where the ratio of the light of the transverse direction of a tree crown by which incidence is carried out is big)
On the other hand in the competition involving light, a target has grass plant under woody plant's oppression, and he presupposed that only the optical resources which reach forest floor can be exploited. Therefore, the remainder which deducted light intensity absorbed by foliage of each woody plant among the light irradiated by the amount of wood presupposed that the grass plant layer is reached. In addition, the model of upper Monsi and Saeki (1953) was used also about the optical attenuation pattern in the grass plant layer.
It carries out based on the optical conditions of each woody plant individual for which it asked as mentioned above, the optical conditions of the grass plant layer, etc., and the amount of addition photosynthesis on the 1st is computed based on Sim-CYCLE. Although Kimoto's amount of photosynthesis is calculated with an individual base, since it assumes that a tree crown does not overlap between the Kimoto individuals in this model, in case it integrates with the amount of photosynthesis for every tree crown, only the self shade-ed by an individual's own foliage is considered.

Breathing and Turnover

Two kinds, maintenance breathing and growth respiration, are treated. Fundamentally, although both the model and the parameter were obtained from Sim-CYCLE, unlike Sim-CYCLE, by this model, woody plant's Core material section presupposed that deciduous woody plant who presupposed that maintenance breathing is not carried out and enters at the dormant period does not do maintenance breathing, either. And first, when less than the required amount of resources which needs for maintenance breathing the resources which can be exploited, when insufficient, it was still presupposed using storage resources (conversion efficiency Efficiency_transout and a conversion loss are emitted into the atmosphere) that a day is included in a liter in 5% /of the weight of a leaf also with woody plant and grass plant. As for Turnover, the model and the parameter were based on LPJ. Moreover, also in the dormant period, only turnover presupposed that it occurs.

Decomposition

It was assumed that there were a litter ingredient decomposed for a short period of time (from several months to several years) and a mineral soil ingredient decomposed in a long period of time (from tens of to several century) in soil carbon. The decomposition rate of any soil carbon is the function of temperature and soil moisture content. About the concrete method, it was based on Sim-CYCLE.

foliation

Deciduousness or an evergreen attribute is given to each PFTs, respectively, and a leafing stage and a fallen-leaves term change under the following rule in deciduous PFTs. These rules were acquired from LPJ-DGVM with the parameter. (In case of *, however this algorithm, under environment warm at humectant, since a leaf is pickled all the year round even if it is Deciduousness PFT, it may change from now on)

Dormant period -> activity period :
- Conditions : the normal temperature for one week should exceed minimum base temperature (Tmpbase) recently, and, moreover, average water_status for one week should exceed minimum water stress factor (Ms_per_whcmin) recently.
- Event : use of storage resources is attained. Giving the conversion efficiency in that case by parameter Efficiency_transout, (here, 0.9 is assumed) the conversion loss presupposed that it is emitted into the atmosphere as carbon dioxide. foliation quantity after entering at an activity period was given by "Maximum exhibition Leaf quantity xmin[1. 0, gdd/GDDreq]", and assumed that it went up gradually according to accumulation of gdd (growth degree day). GDDreq is gdd needed even for the maximum exhibition leaf here, and this is defined for every PFT. About the maximum exhibition Leaf quantity, the calculation method is indicated below.

Activity period -> dormant period :
- Conditions : the normal temperature for one week is less than minimum base temperature (Tmpbase) recently, or average water_status for one week be less than minimum water stress factor (Ms_per_whcmin) recently.
- Event : all the leaves that were being made to foliation till then are included in a liter. In addition, all grass plant assumed that it was perennation, and even if the leaf fell, I thought that the root biomass and stock resources remained.

grass plant's maximum exhibition Leaf quantity :
(1) The restrictions by the original amount of water supply and two kinds of restrictions of amount of resources A in which (2) use is possible are carried out. The maximum exhibition Leaf quantity is the smallest value of maximum exhibition Leaf quantity max1 and max2 which each restrictions allow.
Formula

woody plant's maximum exhibition Leaf quantity :
(1) tree crown size and (2) -- four kinds of restrictions of the water traffic by sapwood and amount [ in which the original amount of water supply and (3) (4) use are possible ] of resources A are carried out. The maximum exhibition Leaf quantity is the smallest value among maximum Leaf quantity max1, max2, max3, and max4 which each restrictions allow.
Formula
grass plant's growth

A growth routine is called after a foliation routine every day. However, a call will not be produced from a quiet period and dormancy release less than on the 10th. By a growth routine, the following process is performed in order. (1) Growth of a root : compute the optimal leaf area index (laioptimum) in the grass plant layer from average forest floor par of one week of past first. The optimal leaf area index is a leaf area index from which par serves as a light compensation point at the lowermost part of the grass plant foliage. And that insufficiency is made to produce, if it asks for weight of root needed when this leaf area index is attained from a lower type and the present weight of root is less than this (unless use resources are lost).
Formula
The cost per unit weight of leaf for obtaining water and nutritive substance assumes changing according to the status for water supplies, and this formula obtained the model parameter from LPJ-DGVM.
(2) Stock resource supplement : if it seems that the amount of storage resources is less than weight of leaf which is carrying out the present exhibition leaf, the amount of storage resources will be increased until these both are in agreement. Even if it pays its attention only to direct cost on the occasion of storage of resources, conversion to the turn of tide from a storage facility and a storage compound, a storage cell, tissue, construction of an organ, etc. are needed (Lambers et al., 1998). So, in this model, it presupposed that only the fixed rate (Efficiency_transin) of the distributed resources serves as storage resources, and the loss produced in this case presupposed that it is emitted as carbon dioxide into the atmosphere. In addition, 0.9 was assumed to Efficiency_transin.
(3) Breeding : all the surplus resources that can be exploited at this time assumed that it was used for breeding, and were included in the liter.

woody plant's growth

A growth routine is once called per month. However, about Deciduousness woody PFTs, a call will not be produced from a quiet period and dormancy release less than on the 30th. By a growth routine, the following process is performed in order.
(1) a tree crown -- withering -- raising -- : -- every -- the PAR compensation point (a parameter, PARmin) is beforehand given to PFT. When there is a tree crown layer with which the average PAR for just before one month is less than this PAR compensation point, it has been withered in 10cm unit sequentially from the lowermost part of a tree crown, and crown_depth is adjusted. In addition, the tree crown layer which had withered once presupposed that a leaf cannot be pickled again, even if optical environment had been improved.
(2) Growth of a root : make the insufficiency produce, if it asks for weight of root needed at the time of the maximum exhibition leaf from a lower type and the present weight of root is less than this (unless available resources are lost).
Formula
crown_areaxcrown_depthxLAD_max/SLA is the maximum weight of leaf which can go into a tree crown here. As structure of a fundamental model, although it is the same as above-mentioned Kusamoto's growth process, it sets to Kimoto's growth. It Formula is the average value for one month of the just before instead of one last week.
(3) A supplement of storage resources : it is the same as grass plant PFT.
(4) Growth of a trunk : the resources which remain at this time are used for growth of a trunk. The trunk biomass was given by the following formula from a diameter of a tree at breast-height and wooden height.
Formula
Although the specific value of a seed should have been essentially used for the parameter Allometry3, 300 (kg/m2/m) which Hytteborn (1975) presumed to all PFT(s) was used for it here. On the other hand, based on the kinetic property of a trunk, tree height was given by the following formula as a function of DBH (Huang et al.1992).
Formula
The maximum big tree quantity and S to which Height_max was given for every woody plant PFT here are an initial growth rate. Although these are due to be presumed based on the forest structure data in each biome, at present, they have given 30 (m) and 100 (m/m) to all woody PFT, respectively.
However, in this model, since a tree crown assumes not occupying the same space between individuals, spatial restrictions may be imposed to extension of tree height. In such a case, even if DBH became a however big value, more than the restrictions, tree height presupposed that it cannot elongate. In the range of the bottom of the above restrictions, and extant available resources, the realizable amount of maximum sapwood width growth is calculated numerically, and growth of the width and the height of a trunk is made to perform.
(5) Increase a tree crown cross-section area according to increase: of a tree crown cross-section area, then the amount of growth of a trunk. The maximum possible value of the diameter of a tree crown is given by the following relation based on Reinecke's rule (Zeide, 1993).
Formula
Allometry2 was a constant, was been alike and based on Sitch (2003), and gave 40.0 to all woody plant PFT here. In addition, the spatial restrictions based on assumption that increase of a tree crown cross-section area does not occupy further the space where a tree crown is the same between individuals with the maximum (parameter CA_max) given beforehand are given. Although 15.0 (m2) is given to CA_max to all woody plant PFTs now based on Sitch (2003), this may be redefined from now on.
(6) Breeding : it is the same as grass plant PFT.

disturbance

Only the fire was considered as a disturbing factor. Thonicke et al. (2001) developed to the fire model and what Sitch et al. (2003) simplified on the occasion of the inclusion to LPJ-DGVM was adopted as it. In this model, a fire breaks out, only when fuel load (biomass + liter) is being accumulated as for 2 or more 200 gC/m, and the fire outbreak probability for one year in that case is given as a function of liter moisture content from a lower type.
Formula
however
Formula
me is the compensation clause of the difference in the rate of ignition to the woody plant litter and the grass plant litter here, and it was defined as x(ground part woody plant biomass / ground up all biomass)0.3+(ground part grass plant biomass / ground up all biomass) x0.2.
In the division which the fire produced, it was assumed that all the biomasses of woody plant who died in the flames, surviving woody plant's foliage biomass, all the grass plant's biomasses, and all liters were emitted as CO2.However, generally many carbonization pieces of wood remain in the remains of a fire, and since the biological breakdown of these is hard to be carried out, they pile up in the earth for a long time as a carbon stock. Moreover, although those carbonization pieces of wood are considered that an albedo falls in the state where it is sprinkled on the ground, this model is not taking these effects into consideration. A characteristic value is given to the probability of survival of woody plant in case of a fire for every PFT (parameter: Fire_resist). Although this value was also acquired from LPJ-DGVM, since they have not quoted the source of these values, it is unknown whether it is the number which can set reliance how much.

Death (based on factors other than a fire)

Death is clearly treated only by woody plant PFT and is suggestively expressed by high Turnover rate by grass plant PFT. woody plant's mortality rate is the sum total of Background mortality, Heat stress, and Bioclimitic limit mortality, is once computed for every individual for a year, and is made to die probable according to the value. Hereafter, the definition of each mortality rate is described.
Background mortality is probable death fluctuated according to the optical environment where the individual was placed, and the probability is given by the following formula.
Formula
gppannual is the total output for one year of the individual (g in drymass) here. crown_areaxcrown_depthxLAD_max is the maximum leaf area which can be developed in a tree crown. K_mort1 and K_mort2 are parameters given to each woody plant PFT, and they presumed these so that woody plant's age distribution in an actual forest could be reproduced. According to optical environment, relative vitality (relative vigor), i.e., the character relevant to the ranking and opposite characteristic of disease in competition, can be found, and although Background mortality assumes that it influences the size of mortality rate, by this model, the annual total output of a leaf area (at time of maximum exhibition leaf) this is used for it as an index of optical environment in that case. Although the amount of annual growth per leaf area was generally used for this index (Warning 1983, Warning and Schlesinger 1985, Leemans and Prentice 1989, and Prentice and Leemans 1990), by this model, woody plant's maximum size was restricted by the congestion degree of a forest, and in order that the individual that it cannot grow up even if optical environment is good might also come out, I thought that it was not appropriate to make Background mortality into the function of the amount of growth.
The mortality rate by Heat stress is computed according to a lower type only about three sorts (PFT No 6, 7, and 8) of frigid woody plant PFT, and is added to the whole mortality rate. This obtained the model and the parameter from LPJ-DGVM.
Formula
In addition, tmpair(d) is the temperature in d days.
The death by Bioclimitic limit is the environmental range which was defined for every PFT and which can be survived, and obtained the model and the parameter from LPJ. The way of giving is simple, and the PFT is not sustainable if the normal temperature of the coldest moon for the past 20 years is less than the value (parameter: TCmin) defined for every woody PFT. Moreover, about the frigid fallen-leaves needle-leaf tree (Boreal needle-leaved summergreen, PFT no.7), also when the difference of the normal temperature of the coldest moon and the warmest moon was less than 43 degrees C in the average for 20 years, it was presupposed that it is not sustainable.

The method of a simulation

In each grid of T42 (128x64), parts for ten wood of 30mx30m(*) are made to simulate independently, and it is considered as the central value of a grid with the average. Since the geographical hetero nature in a grid does not treat in the present version, the parameter which the amount of this ten wood has is the same. The problem of disturbance is raised as main reasons for making parts for two or more small wood simulate. For example, once it will be generated, the forest fire which occurs frequently by a frigid zone forest will not be concerned with the size for the wood currently simulated, but all will almost destroy it completely. Thus, it is not appropriate to acquire the central value of a grid from a part for the single wood sharply changed in opportunity.
: About the area which vegetation with big average tree crown size produces like a tropical a lot of rain wood, it is also under examination to extend to an about [ 100mx100m ] size.

Parameter list

Position information on a grid
    Latitude : latitude
    Altitude : altitude (m)
Soil parameter (a definition is given for every grid)
    WHCup: water holding capacity within 30cm-depth soil (mm)
    WHClow: water holding capacity below 30cm-depth soil (mm)
    Hyd_cond : soil hydraulic conductivity from upper to lower layer (day-1)
    Albedosoil: albedo on soil surface witout vegetation
A form, an allocation (a definition is given for every PFT)
    Height_max : maximum tree height (m)
    CA_max : maximum crown area (m2)
    LAD_max : maximum leaf area density (m2/m3)
    S : initial value of relative growth rate of height to diameter (m/m)
    Age_leaf : leaf age (year)
    SLA : specific leaf area (m2/g)
    FR_max : maximum leaf-to-root mass ratio (0.0-1.0)
    P_root_up : proportion of root mass within upper soil layer (0.0-1.0)
    Allometry1, 2, 3 : allometry parameter 1, 2, 3 (no dimension)
Breathing (a definition is given for every PFT)
    SARMf, s, r : specific maintenance respiration rate at 15 C for foliage, sapwood, root (g/g/day)
    SARGf, s, r : specific growth respiration rate for foliage, sapwood, root (g/g)
Photosynthesis (a definition is given for every PFT)
    PARmin photosynthesically active radiation at compensation point: (μmol photon/m2/ s)
    EK0: light attenuation coefficient (no dimension)
    Lue0: control light dependence coefficient (mol CO2mol photon-1)
    Pmax : maximum stomatal conductance
    Tmpopt0 : optimum temperature for photosynthesis (Cecius)
    Tmpmin : minimum temperature for photosynthesis (Cecius)
    Tmpmax: maximum temperature for photosynthesis (Cecius)
    GSb0, b1, b2 : stomatal conductance parameter 1, 2, 3 (mmol H2O /m2/s)
    Km_nstl : maximum stomatal conductance
    Kmci : dependence of photosynthesis on intercellular CO2 concentration (ppmv)
    Cmpcd0 : CO2 compensation point (ppmv)
Other metabolism (a definition is given for every PFT)
    Turnoverf, s, r : fixed turn over time for foliage, sapeood, and root (yr-1)
    Efficiency_transin : energy transformation efficiency from available to stock resource
    Efficiency_trans out : energy transformation efficiency from stock to available resource
phenology (a definition is given for every PFT)
    Tmpbase : minimum base temperature for foliation for dioceious PFTs (Cecius)
    Status_waterbase : minimum base water status for foliation for dioceious PFTs (0.0 - 1.0)
    GDDreq : Growing Degree Day requirement to grow full leaf coverage
    Ms_per_whcmin : Minimum water stress factor for drought deciduous PFT
Fixing (a definition is given for every PFT)
    P_establish : establishment probability when climate permit (1/m2/year)
    Precmin : minimum precipitation for woody PFT establishment (mm/YEAR)
    TCmax : maximum coldest-month temperature (Cecius)
    GDDmin : Minimum growth-degree-day sum (5 Cedius degree base)
Death (a definition is given for every PFT)
    K_mort1 : parameter in background mortality equation (no dimension)
    K_mort2 : parameter in background mortality equation (no dimension)
    TCmin : minimum coldest month temperature for survive (Cecius)
    Fire_resist : probability of survive when fire occurs (0.0-1.0)

Variable list
Dry weight
    masscrown : foliage mass of a woody individual (g in dry-matter)
    masstrunc : trunc mass of a woody individual (g in dyr-matter)
    massroot : root mass of a woody individual (g in dry-matter)
    massstock: stock mass of a woody individual (g in dry-matter)
    gmassleaf : leaf mass density of grass (g/m2in dry matter)
    gmassroot : root mass density of grass (g/m2in dry matter)
    gmassstock : stock mass density of grass (g/m2in dry matter)
A form, a character
    height : tree height (m)
    crown_diameter : crown diameter of a woody individual (m)
    crown_depth : crown depth of a woody individual (m)
    crown_area : cross section crown area (m2)
    dbhsapwood : sapwood diameter at 1.3m height (m)
    dbhheartwood : heartwood diameter at 1.3m height (m)
    la : leaf area of a individual (m2)
    laig : leaf area index of grass layer (m2/m2)
Water environment
    ms_per_whcup : moisture content per water-holding-capacity in upper soil layer (0.0-1.0)
    ms_per_whclow: moisture content per water-holding-capacity in lower soil layer (0.0-1.0)
    status_water : for each woody individual (0.0-1.0)
Optical environment
    par photosynthetically active radiation: ($mu;mol photon / m2/s)
    radtop : shortwave radiation at the atmosphere-top
    eK : light attenuation coefficient (no dimension)
Climate
    gdd : growth degree day (5 degree Cecius base)
c.3. Schedule
FY 2004
    April A code check and vectorization complete completion and the 1 grid calculation version model.
    May Data is collected to presumption and the object for adjustment of a parameter.
    June to July Presumption and adjustment of a parameter
    August A code is changed and parallelized so that it can apply by all ball grids.
    September The off-line experiment by all ball grids is conducted on an Earth Simulator.
    October-following March Paper writing, additional simulation
d. The research program in FY 2003
The vegetation model of all the dynamic balls used as the base is designed, and Sim-CYCLE is built.
e. Reports in FY 2003
Until now, the code treating the vegetation change in one grid was completed mostly, and prepared the ground of making the vegetation change by all ball grids simulating from now on.
f. Consideration
The result which should be considered has not been obtained yet.
g. Quotation reference
Foley J. A., M. H. Costa, C. Delire, N. Ramankutty, and P. Snyder, Green surprise- How terrestrial ecosystems could affect earth's climate, Frontier Ecological Environment, 1, 38-44, 2003.

Ito A., and T. Oikawa, A simulation model of the carbon cycle in land ecosystems (Sim-CYCLE): a description based on dry matter production theory and plot-scale validation, Ecological Modeling, 151, 143-176, 2002.

Haxeltine A., and I. C. Prentice, BIOME3: An equilibrium terrestrial biosphere model based on ecophysiological constrains, resource availability, and competition among plant functional types, Global Biogeochemical Cycles, 10, 693-709, 1996.

Haxeltine A., I. C. Prentice, and I. D. Cresswell, A coupled carbon and water flux model to predict vegetation structure, Journal of Vegetation Science, 7, 651-666, 1996.

Hytteborn H., Deciduous woodland at Andersby, eastern Sweden, above-ground tree and shrub production, Acta Phytogeographica Suecica, 61, 1-61, 1975.

Jackson R. B., J. Canadell, J. R. Ehleringer, H. A. Mooney, O. E. Sala, and E. D. Schulze, A global analysis of root distributions for terrestrial biomes, Oecologia, 108, 389-411, 1996.

Kira T., and T. Shidei, Jap. J. Ecol., 17, 70-87, 1967.

Lambers H., F. Stuart, I. Chapin, T. L. Pons, H. Lambers, and T. L. Pons, Plant Physiological Ecology, Springer Verlag, 1998.

Leemans R., and I. C. Prentice, FORSKA, a general forest succession model, Meddelanden fran Vaxtbiologiska Instotutionen, Uppsala (ISSN 0348-1 417), 1989.

Monsi M., and T. Saeki, Uber den Lichtfaktor in den Pfanzengesellschaften und seine Bedeutung fur die Stoffproduktion, Japapese Journal of Botany., 14, 22 -52, 1953.

Prentice I. C., W. Cramer, S. P. Harrison, et al., A global biome model based on plant physiology and dominance, soil properties and climate, Journal of Biogeography, 19, 117-134, 1992.

Prentice I. C., and R. Leemans, Pattern and process and the dynamics of forest structure: a simulation approach, Journal of Ecology, 78, 340-355, 1990.

Sitch S., B. Smith, I. C. Prentice, A. Arneth, A. Bondeau, W. Cramer, J. Kaplan, S. Levis, W. Lucht, M. Sykes, K. Thonicke, and S. Venevski, Evaluation of ecosystem dynamics, plant geography and terrestrial carbon cycling in the LPJ Dynamic Vegetation Model, Global Change Biology, 9, 161-185, 2003.

Thonicke K., S. Venevsky, S. Stich, et al., The role of fire disturbance for global vegetation dynamics: coupling fire into a Dynamic Global Vegetation Model, Global Ecology and Biogeography, 10, 661-677, 2001.

Warning R. H., Estimating forest growth and efficiency in relation to canopy leaf aera, Advances in Ecological Research, 13, 327-354, 1983.

Warning R. H., and W. H. Schlesinger, Forest Ecosystems: concepts and Management, Academic Press, Orlando, Florida, 1985.

Zeide B., Primary unit of the tree crown, Ecology, 74, 1598-1602, 1993.

h. The announcement of a result
< oral Announcement & gt;
Presenter name: Sato HisashiAKohyamaTakashi
Announcement title: Development of an integrated terrestrial ecosystem model for global changing prediction
Announcement place etc.: Seed biology meeting international symposium 2003 (October, 2003 Sapporo)
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