• Journal of Ecology and Environment
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• v.33 no.2
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• pp.165-173
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• 2010

Soil respiration ($R_S$) is a critical component of the annual carbon balance of forests, but few studies thus far have attempted to evaluate empirical regression models in $R_S$. The principal objectives of this study were to evaluate the relationship between $R_S$ rates and soil temperature (ST) and soil water content (SWC) in soil from a cool-temperate deciduous broad-leaved forest, and to evaluate empirical regression models for the prediction of $R_S$ using ST and SWC. We have been measuring $R_S$, using an open-flow gas-exchange system with an infrared gas analyzer during the snowfree season from 1999 to 2001 at the Takayama Forest, Japan. To evaluate the empirical regression models used for the prediction of $R_S$, we compared a simple exponential regression (flux = $ae^{bt}$Eq. [1]) and two polynomial multiple-regression models (flux = $ae^{bt}{\times}({\theta}{\nu}-c){\times}(d-{\theta}{\nu})^f:$ Eq. [2] and flux = $ae^{bt}{\times}(1-(1-({\theta}{\nu}/c))^2)$: Eq. [3]) that included two variables (ST: t and SWC: ${\theta}{\nu}$) and that utilized hourly data for $R_S$. In general, daily mean $R_S$ rates were positively well-correlated with ST, but no significant correlations were observed with any significant frequency between the ST and $R_S$ rates on periods of a day based on the hourly $R_S$ data. Eq. (2) has many more site-specific parameters than Eq. (3) and resulted in some significant underestimation. The empirical regression, Eq. (3) was best explained by temporal variations, as it provided a more unbiased fit to the data compared to Eq. (2). The Eq. (3) (ST $\times$ SWC function) also increased the predictive ability as compared to Eq. (1) (only ST exponential function), increasing the $R^2$ from 0.71 to 0.78.

• The Korean Journal of Ecology
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• v.26 no.5
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• pp.289-296
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• 2003

The ecological process-based approach provides a detailed assessment of belowground compartment as one of the major compartment of carbon balance. Carbon net balance (NEP: net ecosystem production) in forest ecosystems by ecological process-based approach is determined by the balance between net primary production (NPP) of vegetation and heterotrophic respiration (HR) of soil (NEP=NPP-HR). Respiration due to soil heterotrophs is the difference between total soil respiration (SR) and root respiration (RR) (HR=SR-RR, NEP=NPP-(SR-RR)). If NEP is positive, it is a sink of carbon. This study assessed the forest carbon balance by ecological process-based approach included belowground compartment intensively. The case study in the Takayama Station, cool-temperate deciduous broad-leaved forest was reported. From the result, NEP was estimated approximately 1.2 t C $ha^{-1} yr^{-1}$ in 1996. Therefore, the study area as a whole was estimated to act as a sink of carbon. According to flux tower result, the net uptake rate of carbon was 1.1 t C $ha^{-1} yr^{-1}$.

• Asian Journal of Atmospheric Environment
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• v.7 no.1
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• pp.8-16
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• 2013

The fog water chemistry and deposition in northern Japan were investigated by fog water and throughfall measurements in 2010. Fog water was sampled weekly by an active-string fog sampler at Lake Mashu from May to November. Throughfall measurements were conducted using rain gauges under three deciduous trees along the somma of the lake from August to October. The mean fog deposition rate (flux) was calculated using throughfall data to estimate the total fog water deposition amount for the entire sampling period. $NH_4{^+}$ and $SO{_4}^{2-}$ were the most abundant cation and anion, respectively, in the fog water samples. A mean pH of 5.08 in the fog water, which is higher than those in rural areas in Japan, was observed. The [$NH_4{^+}$]/[$SO{_4}^{2-}$] equivalent ratio in fog water was larger than 1.0 throughout the study period, indicating that $NH_3$ gas was the primary neutralizing agent for fog water acidity. The mean rate and total amount of fog water deposition were estimated as 0.15 mm $h^{-1}$ and 164 mm, respectively. The amounts of nitrogen and sulfate deposition via fog water deposition were corresponded to those reported values of the annual deposition amounts via rainfall.

• The Korean Journal of Ecology
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• v.22 no.3
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• pp.119-129
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• 1999

The bryophyte communities on the forest floor of the mixed coniferous and deciduous broad-leaf forest and the evergreen coniferous forest of cool temperate and subalpine zones in Mts. Taebaek, Odae and Sulak of Tabaek Range were investigated from. the numerical and phytosociological viewpoints. As a result, four bryophyte communities were recognized there, considering the species composition of vascular vegetation; A. Thuja koraiensis-Abies nephrolepis/Taxus caespitosa-Pinus pumila/Hylocomium splendens-Pleurozium schreberi community, B: Sasamorpha borealis-Abies nephrolepis/Plagiomnium cuspidatum- Aulacomnium heterostichum community, C. Abies holophylla-Abies nephrolepis/Thuidium recognitum-Trachycystis immarginata cristatus community, D. Meehania urticifolia-Abies nephrolepis/Hylocomiopsis ovicarpa-Taxiphyllum aomoriense community. Among these, the community A was distributed in higher altitudes and characterized by the species group of the holarctic elements, e.g. Hylocomium splendens, Pleurozium schreberi, Dicranum majus, etc. limited in subarctic; subalpine and arctic; alpine zones and was confirmed as synusies of the Thujo-Abietetum nephrolepidis Song 1991 and Taxo-Pinetum pumilae Song 1985 belonging the Vaccinio-Piceetea Br.-Bl. 1939. In contrast the communities B, C and D were distributed in the mixed coniferous and deciduous broad-leaf forest of lower altitudes and characterized by the elements of the cool temperate; montane zone. They were confirmed as synusies belonging to the Corylo-Quercetum mongolicae Song 1988. By the result of the numerical syntaxonomical analysis such as cluster analysis, interspecific association, PCA, the communities were largely divided into the two types. The two types coincided with the community units or the diagnostic species of the bryophyte communities of the subalpine zone and the montane zone, respectively. Also the analysis revealed that the division of the above two forest zones are justifiable. Up to date many investigator have described the coniferous forest distibuted above 1000m in Taebaek mountains as the forest vegetation of subalpine zone. However, from the results of the present study, the boundary of the mixed forest and the true subalpine coniferous forest was elucidated to be ca. 1,500 m phytosociologically. Species richness was the highest in the community A, and the other four communities showed a similar species richness.

• The Korean Journal of Quaternary Research
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• v.15 no.2
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• pp.75-81
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• 2001

We have analyzed the pollen sequence since the Late Glacial at Sorori Archaeological Site. The Sorori Site is an open site located at Soro-ri, Oksan-myeon, Cheongwon-gun, Chungchongbukdo. The main results are as follows: Four forest zones have been distinguished. \circled1 OS-1 zone : Pinus-Abies-Picea forest (the sub-alpine conifer forest), the Late Glacial (about 15,000~10,000yr. B.P.) ; \circled2 OS-2 zone : Pinus-Colyus forest (the mixed conifer and deciduous broad-leaved forest), R I (about 10,000 yr.B.P.) : \circled3 OS-3 zone : Alnus-Quercus forest (the cool temperate deciduous broadleaved forest), R II(about 10,000~2,000yr.B.P.) : \circled4 OS-4 zone : Pinus forest (the conifer forest), R III (about after 2,000yr.B.P.)

• The Korean Journal of Quaternary Research
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• v.15 no.2
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• pp.93-99
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• 2001

We have analyzed the pollen sequence since the end of Last Glacial Maximum at Yugawanuma moor The Yugawanuma moor($39^{\circ}15'N$, $140^{\circ}45'E$) is situated in an closed depression of an old landslide about 590m a.s.l. near the boundary between Iwate and Akita Prefecture. The main results are as follows : Five forest zones have been distinguished. \circled1 Y-I zone : Pinus-Picea-Betula zone (the subalpine forest.the end of the Last Glacial Maximum), \circled2 Y-II : Betula zone (the subalpine forest.the Late Glacial), \circled3 Y-III : Quercus-Betula-Ulmus/Zelkova zone (the lower subalpine or the upper montane forest.R I), \circled4 Y-IV : Fagus zone (the cool temperate deciduous broad-leaved forest.R II), \circled5 Y-V : Fagus-Quercus-Cryptomeria zone (the mixed forest conifer and deciduous broad-leaved forest.R III).

• The Korean Journal of Quaternary Research
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• v.17 no.2
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• pp.17-23
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• 2003

In Korea terrestrial fluvial sequences can be used as pedological and sedimentological markers indicating a millenium-scale environmental and climatic changes imprinted in fluvial sub-environments, which in turn are represented by the cyclicity of fluvial sands, backswamp organic muds, and flooding muds intercalations of frostcracked or dessicated brown paleosols. Post LGM and Holocene fluvial and alluvial sedimentary sequences of Korea are formed in such landscapes of coastal, floodplain, backswamp and hillslope areas. Among them, the most outstanding depositional sequences are fluvial gravels, sands and organic mud deposits in coastal, fluvial, or alluvial wetlands. The aim of this study is to explain the sedimentary sequences and palynofloral zones since the last 15,000years, on the basis of organic muds layers intercalated in fluvial sand deposits. Jangheung-ri site of Nam river, Soro-ri site of Miho river, Youngsan rivermouth site in Muan, Oksan-ri site of Hampyeong and Sanggap-ri site of Gochang are illustrated to interpret their sedimentary facies, radiocarbon datings, and palynofloral zonation. Up to the Middle to Late Last Glacial(up to 30-35Ka), old river-bed, flooding, and backswamp sequences contain such arboreal pollens as Pinus, Abies, and Picea, and rich in non-arboreal pollens like Cyperaceae, Gramineae, Ranunculaceae, and Compositae. During the LGM and post-LGM periods until Younger Dryas, vegetation has changes from the sub-alpine conifer forest(up to about 17-11Ka), through the conifer and broad-leaved deciduous forest, or mixed forest (formed during 16,680-13,010yrB.P), to the deciduous and broad-leaved forest (older than 9,500yrB.P). In the Earliest Holocene flooding deposits, fragments of plant roots are abundant and subjected to intensive pedogenic processes. During Holocene, three arboreal pollen zones are identified in the ascending order of strata； Pinus-Colyus zone(mixed conifer and deciduous broad-leaved forest, about up to 10Ka), Alnus-Quercus forest (the cool temperate deciduous broad-leaved forest, about 10Ka-2Ka), and Pinus forest (the conifer forest, about after 2Ka), as examplified in Soro-ri site of Cheonwon county. The palynological zonations of Soro-ri, Oksan-ri, Sanggap-ri, Youngsan estuary, and Gimhae fluvial plain have been recognized as a provisional correlation tool, and zonations based on fluvial backswamp and flooding deposits shows a similar result with those of previous researchers.

• Journal of The Geomorphological Association of Korea
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• v.17 no.1
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• pp.39-48
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• 2010

This is a case study to research the environmental changes that occurred during the Latter Half of the postglacial age around the Basin of Onyang River in Asan, Korea. In line with this purpose, the author performed a pollen analysis and a radiocarbon dating on the deposits of alluvial fan around the upper Geumgok River, a tributary of Onyang River. Sampling point was at the altitude of about 67.5 meters, which belongs to the central zone of the cool temperate forest. The followings are the results of the study. The study area has passed through SC-I (the coniferous forest period in which Pinus was dominant), SC-II (the deciduous broad-leaved forest period in which Quercus and Castanea were dominant) and SC-III (the mixed conifer and deciduous broad-leaved forest period, in which Pinus, Quercus and Ulmus/Zelkova were dominant) respectively since about 3,000 yrB.P. SC-I period and SC-II period are presumed to be between about 3,000 and 2,000 yrB. P., and SC-III period to begin after 2,000 yrB.P. In comparison with the nationwide pollen zone during the postglacial age, SC-I and SC-II periods are contrasted with the R-IIIa zone and also the SC-III zone with the RIIIb zone. In addition, it is assumed that Pinus densiflora forest luxuriated there since 2,000 yrB.P. due to the destruction of forests, and that a lot of Fagopyrum pollen appeared; altogether, it was the so-called human interference period, from which forests began to be markedly destroyed. It is concluded that in those days inhabitants leaded agricultural life.

• Journal of The Geomorphological Association of Korea
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• v.19 no.2
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• pp.173-185
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• 2012

Authors performed pollen analysis in deposits at a coastal plain at Yeongjong-do Island located in Incheon, South Korea. Sampling site (7.2 m a.s.l.) belongs to the cool temperate deciduous broad-leaf forest. Environmental changes since 8,900 yrs B.P. reconstructed from pollen analysis are as follows; JS-I stage (c.a. 8,900~8,500 yrs B.P. ) was cool temperate northern mixed-forest which is comparable to the early PostGlacial pollen stage RI in Japan, in which Pinus and Quercus were dominant and Abies and Picea were also found. At that time, climate was relatively cooler and dryer than today. JS-II stage (sometime between 8,500~4,000 yrs B.P.) was Pinus-dominant coniferous forest, which is comparable to the mid-Post-Glacial pollen stage RII. Mixed forest of Pinus, Quercus and Carpinus was dominant in JS-III stage (c.a. 4,000 yrs B.P). We assumed that JS-II and JS-III stage were relatively warmer and more humid than JS-I stage, and were more like present conditions. JS-IV stage (sometime between 4,000~900 yrs B.P.) was Pinus-dominant coniferous forest which is comparable to the late Post-Glacial pollen stage RIII. JS-V stage (c.a. 900 yrs B.P. ~present) was second growth Pinus-dominant coniferous forest stage. During the last stage, non-arboreal pollen was more common than arboreal pollen and Fagopyrum appeared among the herbaceous plant, which indicates that it is comparable to the RIIIb stage which was the age of human interference. From the JS-V stage, humans in the study site started agricultural activities.

• Journal of Ecology and Environment
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• v.29 no.6
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• pp.573-580
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• 2006

A sediment core from the Cheollipo arboretum ($36^{\circ}$ 47' 57'N, $126^{\circ}$ 09' 04') was studied for pollen analysis in order to reconstruct postglacial vegetational change and environmental changes around the central western region of the Korean Peninsula. The record shows four pollen assemblage zones: Zone CHL-I, Quercus stage (ca. 9,300$\sim$6,200 yr BP): zone CHL-II, Quercus-Pinus stage (ca. 6,200$\sim$4,600 yr BP); zone CHL- III, Pinus-Quercus stage (ca. 4,600$\sim$1,160 yr BP): zone CHL-IV and Pinus stage (ca. 1,160 yr BP-present). During the 9,300$\sim$8,500 yr BP, the early Holocene, researchers have guessed a piece of cool-temperate norihern/altimontane mixed coniferous and deciduous broad-leaved forest. Between 8,500$\sim$4,600 yr BP the Quercus dominated the landscape of study area and the established dates of this typical cool-temperate central/montane deciduous broad-leaved forest vegetation might be ca. 6500 yr BP, and then the Pinus developed around the site at ca. 5,700 yr BP. The abrupt increase of Pinus and NAP (non-arboreal pollen) after ca. 1,100 yr BP indicates the vegetation changes due to human activities. From the dynamics of the Chenopodiaceae pollen indicating salt marsh and freshwater pollen flora such as Typha, Trapa, Nymphoides and so forth, we suggest that the tidal flat was altered into freshwater lake around 6,500 yr BP.