• Journal of Korean Society of Forest Science
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• v.21 no.1
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• pp.39-45
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• 1974

The objects of this study are to induce the experimental equation suitable to estimate the height growing process, and to get some information that could be to reduce the error percent on determining the site index. The height growing process per sample plot were made up from the height age curve getted through the stem-analysis of the dominant tree. The 11 equations were calculated in the functional formulas between the age and the dominant height of Alnus hirsuta, Larix leptolepsis, L. Gmelini, P. koraiensis, Abies holophylla, P. rigida, Q. acutissima and Q. aliena. The suitable equation for estimating the guide curve were selected with the highest correlation and the low standard error with comparision on the age-height distributed map as Fig. 2. The suitable equation is different between the species as their calculated results as follows; The growing process of tree height are occasionally found to be polymorphous in the growth pattern as Fig. 3. By this result, the site index are practically found to be always not constant but shows variation to age in same plot as example 5. So, that the site index are estimated from the height-growth curve to age drawing by the stem-analysis or the polymorphic-curve, are concluded to be suitable on the study of site evaluation.

• Journal of Bio-Environment Control
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• v.21 no.1
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• pp.57-65
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• 2012

Fertilization is essential to seedling production in nursery culture, but excessive fertilization can contaminate surface and ground water around the nursery. The objective of this study was to find optimal fertilization practice of container seedling production for reducing soil and water contamination around the nursery without compromising seedling quality. This study was conducted to investigate chemical properties of the growth medium, growth performance, chlorophyll fluorescence, and chlorophyll contents of larch ($Larix$ $kaempferi$) growing under three different fertilization treatments (Constant rate, Three stage rate, and Exponential rate fertilization). Root collar diameter and height of larch were not significantly different among treatments even though the nutrient supply of the exponential treatment was half that of the constant and three stage treatments. Chemical properties of the growth medium showed the same trends as root collar diameter and height. The total biomass and seedling quality index (SQI) were higher at Constant than at other treatments, but both SQI of Constant and Exponential were not significantly different. Photochemical efficiency and chlorophyll contents were lower at Exponential than at other treatments, but not significantly different among treatments. Therefore, Exponential fertilization which is 50% fertilizer of other treatments would maximize seedling growth and minimize nutrient loss.

• Korean Journal of Agricultural and Forest Meteorology
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• v.1 no.1
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• pp.41-51
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• 1999

This study was conducted to investigate the effects of local climatic conditions on the annual increment of Korean white pine planted in Gapyung and Yaungdong. For this, stand variables such as mean DBH, mean height, basal area per hectare, and volume per hectare by stand age were measured and summarized for each locality. Based on these statistics, annual increments for 8 years from stand age 10 to 18 were calculated for each of stand variables. A topoclimatological technique which makes use of empirical relationships between the topography and the weather in study sites was applied to produce normal estimates of monthly mean, maximum, minimum temperatures, relative humidity, precipitation, and hours of sunshine. Then, the yearly climatic variables from 1990 to 1997 for each study site were derived from the spatial interpolation procedures based on inverse- distance weighting of the observed deviation from the climatic normals at the nearest 11 standard weather stations. From these estimates, 17 weather variables such as warmth index, coldness index, index of aridity etc., which affect the tree growth, were computed on yearly base for each locality. The deviations of measured annual increments from the expected annual increments for 8 years based on yield table of Korean white pine were then correlated with and regressed on the yearly weather variables to examine effects of local climatic conditions on the growth. Gapyung area provides better conditions for the growth of Korean white pine in the early stage than Youngdong area. This indicates that the conditions such as low temperature, high relative humidity, and large amount of precipitation provide favor environment for the early growth of Korean white pine. A ccording to the correlation and regression an analysis using local climatic conditions and annual increments, the growth pattern of Gapyung area corresponds to this tendency. However, it was found that the relationship between annual increments and local climatic conditions in Youngdong area shows different tendency from Gapyung. These results mean that the yearly growth pattern could not sufficiently be explained by climatic conditions with high variance in yearly weather variables. In addition, the poor growth in Youngdong area might not only be affected by climatic conditions, but also by other environmental factors such as site quality.

• Journal of Korean Society of Forest Science
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• v.88 no.1
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• pp.73-85
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• 1999

This study was conducted to reveal the characteristics of the early growth by locality for Korean white pine planted in Gapyung and Kwangju, Kyunggi-Do and Youngdong, Choongchungbuk-Do. The effects of local climatic conditions as one of environmental factors on the growth were also analyzed. For this, several stand variables such as number of trees survived, mean DBH, mean height, basal area per hectare, and volume per hectare by stand age were measured and summarized for each locality. Based on these statistics, periodic annual increments for 8 years from stand age 10 to 18 were calculated for each of stand variables. A topoclimatological technique, for the estimation of local climatic conditions, which makes use of empirical relationships between the topography and the weather in study areas was applied to produce reasonable estimates of monthly mean, maximum, minimum temperatures, relative humidity, precipitation, and hours of sunshine over remote land area where routine observations are rare. From these monthly estimates, 17 weather variables such as warmth index, coldness index, index of aridity etc. which affect the tree growth, were computed for each locality. The periodic annual increments were then correlated with and regressed on the weather variables to examine effects of local weather conditions on the growth. Gapyung area provided the best conditions for the growth of Korean white pine in the early stage and Kwangju area ranked second. On the other hand, the growth pattern in Youngdong ranked last overall as expected. It is also found that the local growth patterns of Korean white pine in juvenile stage were affected by typical weather conditions. The conditions such as low temperature, high relative humidity, and large amount of precipitation provide favorable environment for the growth of Korean white pine. Especially, the diameter growth, basal area growth, and volume growth are mainly influenced by the amount of precipitation. However, it is proved that the height growth is affected by both the precipitation and temperature.

• Journal of Korean Society of Forest Science
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• v.101 no.1
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• pp.53-61
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• 2012

This study developed a growth model for Larix leptolepis based on the WLS model to examine the effects of climate change on them. The site index was chosen as the dependent variable and location, weather, and edaphic factor were chosen as independent variables. Simulations were performed under three A1B climate change scenarios with the temperature ranging from $-3.3^{\circ}C$ to $+3.3^{\circ}C$. The simulation results showed that the site index decreased with peak at $-0.8^{\circ}C$. The decrease level of the site index by region was also analyzed. Each scenario, site index has decreased mostly but some region was increased. When the temperature increased up to $3^{\circ}C$, site index was decreased to everywhere.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.3
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• pp.241-247
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• 2001

Boundary line method was adopted to analyze the relationships between rice yield and meteorological conditions during rice growing period. Boundary lines of yield responses to mean temperature($T_a$) and sunshine hour( $S_{h}$) and diurnal temperature range($T_r$) were well-fitted to hyperbolic functions of f($T_a$) =$$\beta$_{0t}$(1-EXP(-$$\beta$_{1t}$ $\times$ ($T_a$) ) and f( $S_{h}$)=$$\beta$_{0t}$((1-EXP($$\beta$_{1t}$$\times$ $S_{h}$)), to quadratic function of f($T_r$) =$\beta$$_{0r}$(1-($T_r$ 1r)$^2$), respectively. to take into account to, the sterility caused by low temperature during reproductive stage, cooling degree days [$T_c$ =$\Sigma$(20-$T_a$] for 30 days before heading were calculated. Boundary lines of yield responses to $T_c$ were fitted well to exponential function of f($T_c$) )=$\beta$$_{0c}$exp(-$$\beta$_{1c}$$\times$$T_c$ ). Excluding the constants of $\beta$$_{0s}$ from the boundary line functions, formed are the relative function values in the range of 0 to 1. And these were used as yield indices of the meteorological elements which indicate the degree of influence on rice yield. Assuming that the meteorological elements act multiplicatively and independently from each other, meteorological yield index (MIY) was calculated by the geometric mean of indices for each meteorological elements. MIY in each growth period showed good linear relationship with rice yield. The MIY's during 31 to 45 days after transplanting(DAT) in vegetative stage, during 30 to 16 days before heading (DBH) in reproductive stage and during 20 days after heading (DAH) in ripening stage showed greater explainablity for yield variation in each growth stage. MIY for the whole growth period was calculated by the following three methods of geometric mean of the indices for vegetative stage (MIVG), reproductive stage (HIRG) and ripening stage (HIRS). MI $Y_{I}$ was calculated by the geometric mean of meteorological indices showing the highest determination coefficient n each growth stage of rice. That is, (equation omitted) was calculated by the geometric mean of all the MIY's for all the growth periods devided into 15 to 20 days intervals from transplanting to 40 DAH. MI $Y_{III}$ was calculated by the geometric mean of MIY's for 45 days of vegetative stage (MIV $G_{0-45}$ ), 30 days of reproductive stage (MIR $G_{30-0}$) and 40 days of ripening stage (MIR $S_{0-40}$). MI $Y_{I}$, MI $Y_{II}$ and MI $Y_{III}$ showed good linear relationships with grain yield, the coefficients of determination being 0.651, 0.670 and 0.613, respectively.and 0.613, respectively.

• Journal of Korean Society of Forest Science
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• v.106 no.2
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• pp.249-257
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• 2017

This study was conducted to analyze the relationship between tree-ring growth of Pinus densiflora and climate factors based on national forest inventory(NFI) data. Annual tree-ring growth data of P. densiflora collected by the $5^{th}$ NFI were first organized to analyze yearly growth patterns of the species. Yearly growing degree days and standard precipitation index based on daily mean temperature and precipitation data from 1951 to 2010 were calculated. Using the information, yearly temperature effect index(TEI) and precipitation effect index(PEI) were estimated to analyze the effect of climate conditions on the tree-ring growth of the species. A tree-ring growth estimation equation appropriate for P. densiflora was then developed by using the TEI and PEI as independent variables. The tree-ring growth estimation equation was finally applied to the climate change scenarios of RCP 4.5 and RCP 8.5 for predicting the changes in tree-ring growth of P. densiflora from 2011 to 2100. The results indicate that tree-ring growth of P. densiflora is predicted to be decreased over time when the tree-ring growth estimation equation is applied to the climate change scenarios of RCP 4.5 and RCP 8.5. It is predicted that the decrease of tree-ring growth over time is relatively small when RCP 4.5 is applied. On the other hand, the steep decrease of tree-ring growth was found in the application of RCP 8.5, especially after the year of 2050. The results of this study are expected to provide valuable information necessary for estimating local growth characteristics of P. densiflora and for predicting changes in tree-ring growth patterns caused by climates change.

• Korean Journal of Plant Resources
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• v.19 no.5
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• pp.580-585
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• 2006

This experiment was conducted to study the effects of sulphuric acid, cutting, cold stratification and hot water on the germination of Sophora japonica seeds, which have difficulty to germinate because they have hard and thick seed coats. The seeds were immersed in 30, 60 and 90% sulphuric acid for 30 minutes as seed scarifications, and cut 1/8, 2/8 and 3/8 of the opposite parts of radicles. As cold stratification the seeds were wrapped in wet towel, and then stored in plastic bags in a refrigerator $(4^{\circ}C)$ for 3, 5 and 10 days. The seeds were immersed in hot water $(90{\sim}95^{\circ}C)$ for 2,5 and 10 minutes. Pretreated seeds represented different germination properties, respectively. After sulphuric acid treatment, the seeds showed an increase in germination (G) and germination index (GI). Compared to the other treatments, 90% sulphuric acid showed the highest G (31.7%) and GI (6.2). The G and GI of cut seeds decreased with the increase of seed cutting lengths. And G and GI of cold stratificated seeds were not significantly different among the days treated (p=0.258). Two minutes treatment of hot water showed lower G and Gl than control, and the seeds were not germinated in 5 and 10 minutes treatments of hot water. At the result of relative growth rate and T/R ratio of seedlings from pretreated seeds, the seedlings from seeds in 90% sulphuric acid treatment represented the highest relative growth rate and T/R ratio.

• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.3
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• pp.109-119
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• 2016

This study was conducted to analyze the effect of yearly changes in growing degree days (GDD) on the potential distribution and growth of Quercus mongolica in Korea. Annual tree-ring growth data of Quercus mongolica collected by the $5^{th}$ National Forest Inventory were first organized to identify the range of current distribution for the species. Yearly GDD was calculated based on daily mean temperature data from 1951 to 2010 for counties with current distribution of Q. monglica. When tree-ring growth data were analyzed through cluster analysis based on similarity of climatic conditions, seven clusters were identified. Yearly GDD based on daily mean temperature data of each county were calculated for each of the cluster to predict the change of potential distribution. Temperature effect indices were estimated to predict the effect of GDD on the growth patterns. In addition, RCP 4.5 and RCP 8.5 of climate change scenarios were adopted to estimate yearly GDD and temperature effect indices from 2011 to 2100. The results indicate that the areas with low latitude and elevation exceed the upper threshold of GDD for the species due to the increase of mean temperature with climate change. It was also predicted that the steep increase of temperature will have negative influences on tree-ring growth, and will move the potential distribution of the species to areas with higher latitude or higher elevation, especially after the year of 2050. The results of this study are expected to provide valuable information necessary for estimating local growth characteristics and for predicting changes in the potential distribution of Q. mongolica caused by climate change.

• Korean Journal of Plant Resources
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• v.22 no.1
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• pp.5-12
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• 2009

Seed priming is a useful technique for rapid and uniform seed germination as well as early seedling establishment. This experiment was conducted to find out the optimum condition for Sorbus alnifolia seed priming with four concentrations of four reagents in germination property and seedling growth performance. The results are summarized as follows: Percent germination (PG) varied 2.67% to 24.67%, and S. alnifolia seeds had the highest PG in the treatment that were primed in 100mM $KNO_3$ solution for 2 days. Mean germination time was the shortest in 200 mM $KNO_3$ solution for 2 days. Seed priming with $KNO_3$ solutions increased germination speed (GS) and germination performance index (GPI) compared with non-primed seeds. Especially seed primed with 100 mM $KNO_3$ solution for 2 days showed the highest GS and GPI. The highest relative growth rate (RGR) and seedling vigor index (SVI) was significantly (p<0.05) different from the control and other treatments, respectively. RGR of height (0.0071) and root collar diameter (0.0141) of seedling from primed seeds were the highest in 400 mM NaCl solution for 2 days. The highest SVI (5.43) was observed in the seedlings from seeds primed in 100 mM $KNO_3$ solution for 2 days. Consequently, the optimum reagent and concentration were $KNO_3$ and 100 mM for the effective germination and seedling growth in S. alnifolia