| 其他摘要 | As the largest terrestrial carbon pool, the aboveground and soil carbon stock of forest
ecosystem occupies respectively 80% and 70% of the global carbon stock. Forests play an
important role in regulating the global carbon balance and mitigating the rise in
atmospheric greenhouse gas concentration. There are many researches about carbon
storage of the forest ecosystem. Due to differences in the research scale and methods, there
are uncertainty and complexity in carbon storage of the forest ecosystem. To reduce the
uncertainty in estimation of carbon sequestration and the error of model simulation results,
it is necessary to accurately quantify the carbon stocks of regional forest ecosystem,
sequestration capacity and the distribution. Four typical forests in Liupan Mountain were
selected in this study: they are Larix principis-rupprechtii (plantation), Pinus
tabulaeformis (plantation), Pinus armandi (natural forest) and Quercus wutaishanica
(natural forest). We studied biomass and carbon storage in these forest systems by field
investigation and laboratory analysis. In addition, we explored the dynamic changes of
carbon sequestration ability of vegetation through analyzing the growth process of
plantations. In order to provide information of the hydro-ecological function of forest litter,
the litter water-holding characteristics are discussed in this paper. Main findings are as
following:
(1) Vegetation and litter carbon storage was 29.87 t·hm -2 (Larix principis-rupprechtii),
58.06 t·hm -2 (Pinus tabulaeformis), 48.5 t·hm -2 (Pinus armandi) and 43.95 t·hm -2
(Quercus wutaishanica), respectively. In spatial distribution, the vegetation carbon storage
followed the order tree layer > litter layer > shrub layer > herb layer. The soil organic
carbon concentration decreased with depth increasing. Pinus tabulaeformis had the lowest
soil carbon storage (109.25 t·hm -2 ), and the mean value of other three forests was 184.50
t·hm -2 . The carbon storage of forest ecosystem was 216.85 t·hm -2 , 167.31 t·hm -2 , 223.58 t·hm -2 and 235.26 t·hm -2 in the four tested forests. The distributions of carbon stock were
followed as: soil layer > vegetation layer > litter layer, indicating that soil carbon pool is
the key part of forest ecosystem and plays a vital role in the forest carbon cycle.
(2) The annual DBH increments of the dominant, average and suppressed trees
showed a consistent trend within the two tree species of Larix principis-rupprechtii and
Pinus tabulaeformis. Their growth began to decline at 12 th and 10 th years when
intermediate thinning would be taken. With the average volume of 0.074 m 3 and 0.070
m 3 , 29a Larix principis-rupprechtii and 30a Pinus tabulaeformis have not yet reached the
maturation stage. We predict the mature age of Larix principis-rupprechtii is 30a and
Pinus tabulaeformis is 35a. The volume growth of the two plantations can be simulated by
quadratic polynomial equations with R 2 > 0.98. From the 12 th year, the carbon
sequestration rate of Larix principis-rupprechtii tended to be a stable level of 2.70
t·hm -2 ·a -1 . The Pinus tabulaeformis, however, grew slowly in the early stage, and the
accumulation of carbon increased rapidly during 18 th -26 th year (4.32 t·hm -2 ·a -1 ), then
decreased with times increasing.
(3) The amount of litters in the four forests was 12.05~26.40 t·hm -2 with thickness of
1.0~4.5 cm. Litter stock (g) and thickness (cm) of Larix principis-rupprechtii forests had a
linear correlation (y = 36.64 + 72.12x，R 2 =0.65). There was no significant correlation in
other three stands. Water immersion method had been applied to determine the variation of
water-hold rate (%) with times (h) among different vegetation types. The regression
equation between water-hold rate and time were y = alnx + b. The modified interception
was 4.31 mm, 1.40 mm, 4.13 mm and 1.39 mm respectively, indicating that Larix
principis-rupprechtii and Pinus armandi had relatively higher water-holding ability.
Keywords: biomass; carbon storage; growth process; carbon sequestration rate; Liupan
Mountain |
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