Ecoinformatics and Soil-Plant Formations - New Ecoinformatics Tools in Environmental Science: Applications and Decision-making - page 667

Carbon storage Y i contained in the ith tree segment (leaves, branches of different
thickness, and large roots) is described by the equation:

Y i ¼ D i exp a i þ b i ð Þ ð 8 : 9 Þ

where D i is the diameter of the ith tree at the height 1.35 m (cm), a i and b i are
empirical coef

cients. As a result, it is considered that tree biomass contains 50 %

of the carbon.
The average annual increase of carbon reserves in ith tree section equals:

D Y i ¼ Y i ð t Þ Y i ð t 1 Þ

The decomposition process of the litter and dead organic matter of soil depends
on the average monthly temperature T s and soil moisture M:

ð Ts T opt Þ = 10 B

f 1 ð T s Þ ¼ h ; f 2 ð M Þ ¼0 : 8 M sat ð Þ þ 0 : 2

where T opt is optimal temperature for the decomposition process ( ≈ 30 ° C), ʸ is the

decomposition constant ( ≈ 2.0), and M sat is the saturation level for soil moisture

(%),

" # 2

d

M d

M opt

B ¼ ; T s ¼ 2 : 3554 þ 0 : 7042T a

d

100 d

M opt

where M opt is the optimal soil moisture under which a restriction of decomposition
velocity is no exists, T a is the average monthly atmospheric temperature, and d is
empirical constant.
Soil water regime is described by the following relation:

W ð t Þ ¼ W ð t 1 Þþ P E A ;

where W is the average monthly water content in the soil, P is the volume of
monthly precipitation, E A is the evapotranspiration:

min P þ E P P

f ½ ð Þ f D ; ½

P þ W ð t 1 Þ W m

ð Þ g when P

E P ;

\

E A ¼

E P when P E P

where f D is the factor re ecting limitative effect when precipitation is less potential

evapotranspiration E P , and W m is the vegetation wilting level.

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