• The Korean Journal of Ecology
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• 제12권4호
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• pp.245-256
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• 1989

Nitrogen cycling was in vestigated in Piuns koraiensis plantations with different ages, 1, 2, 3, 6, 9 and 11 years, which were reforested after clear-cutting. Annual N input by bulk precipitation was 10kg., and output by runoff decreased as the plantation aged, especially in-N. The standing N content of the whole vegetation increased approximately 5 times through 11 years. Understory surpassed P. koraiensis plants in the distribution of standing N content for the initial 9 years, but reversed thereafter. Annual N uptake of P. koraiensis plants increased greatly through 11 years, but that of understory increased somewhat until 9 years and decreased thereafter. The maximum N uptake of the whole vegetation was made in the 9-yr-old plantation. In the 1-yr-old one, 59% of the maximum was already absorbed by understory which mainly consisted to herbs. The recycling coefficient, ratio of annual return to rptake, of the whole vegetation decreased as the plantation aged and the value of understory was greater than that of P koraiensis plants. On the contrary, the N use efficiency, ratio of the net primary production to N uptake, of the whole vegetation increased as the plantation aged and the value of understory was less than that of P. koraiensis plants. Consequently, it is emphasized that understory played an important role in such plantation reforesred after clear-cutting for the initial 9 years.

• Journal of Ecology and Environment
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• 제32권3호
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• pp.159-165
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• 2009

The purpose of this study was to investigate the effects of thinning on fine root biomass and vertical distribution. and litterfall amount in a 50 year old Pinus koraiensis plantation in Chuncheon, Kangwon Province. Fine root (< 2 mm in diameter) biomass ($367\;g/m^2$) in the site 'OC_75', thinning once in 1975, was 68% of those in the site 'CON', no thinning after planting, and in the site 'TC_00', thinning twice in 1975 and 2000. There were no significant differences of dead roots among treatments. Diameter $0{\sim}1\;mm$ roots were vertically decreased only in the TC_00 site. The litterfall was very similar between OC_75 ($5.2\;Mg\;ha^{-1}\;yr^{-1}$) and TC_00 ($4.7\;Mg\;ha^{-1}\;yr^{-1}$), but the composition of litterfall was different: The proportion of leaves and branches was 80% and 13% in OC_75 and 56% and 36% in TC_00, respectively. Reduction of P. koraiensis density by thinning decreased leaf litter as well as fine roots of P. koraiensis, but increased fine roots production by neighboring understory plants offset the reduction of fine roots of P. koraiensis. We suggest that belowground as well as aboveground responses, including both over- and understory vegetation, should be considered to measure the responses of trees in thinned forest ecosystems.

• Journal of Forest and Environmental Science
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• 제28권4호
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• pp.232-241
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• 2012

We investigated the relationship between vegetation type and soil carbon dynamics in even-aged alder (Alnus hirsuta) and Korean pine (Pinus koraiensis) plantations in central Korea. Both forests were located on the same soil parent material and occupied similar topographic positions. Soil $CO_2$ efflux in the two plantations was determined using a dynamic chamber method accompanied by measurements of soil moisture content and temperature. Mean soil temperature was similar in the two plantations, but mean soil water content was significantly higher in the alder plantation than in the pine plantation. In both plantations, seasonal patterns in soil $CO_2$ efflux exhibited pronounced variation that corresponded to soil temperature. Soil water content did not affect the seasonal variation in soil $CO_2$ efflux. However, in summer, when soil temperature was above $17^{\circ}C$, soil $CO_2$ efflux increased linearly with soil water content in the alder plantation. Estimated $Q_{10}$ was 3.3 for the alder plantation and 2.7 for the pine plantation. Mean soil respiration during the measurement period in the alder plantation was 0.43 g $CO_2\;m^{-2}\;h^{-1}$, which was 1.3 times higher than in the pine plantation (0.33 g $CO_2\;m^{-2}\;h^{-1}$). Higher soil $CO_2$ efflux in the alder plantation might be related to nitrogen availability, particularly the concentration of $NO_3{^-}$, which was measured using the ion-exchange resin bag method.

• Journal of the Korean Wood Science and Technology
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• 제31권6호
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• pp.22-30
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• 2003

This study was performed to obtain the basic data for high quality timber production and efficient utilization by investigating the effect of pruning on timber quality of domestic plantation-grown Korean pine (Pinus koraiensis Sieb. et Zucc.). The results were summarized as follows:Dead knots (unsound knots) in the pruned logs occurred more at upper parts when compared with in non-pruned ones. The numbers of knots on surface in heavily pruned trees were less than those in non-pruned trees, but there was no significant difference in moderately pruned trees. The required period to reveal clear timber surface without defects after pruning increased proportionally with the increase of knot diameter. The yield of clear lumber production increased by about 10% after 14 years from moderate pruning. The quality grade of log improved with more pruning practices. Knots appeared the most important factor in lowering the log grades.

• 한국산림과학회지
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• 제99권3호
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• pp.397-403
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• 2010

본 연구는 서로 다른 강도로 간벌 시행 후 4년이 경과한 경기도 광릉시험림 내 46년생 잣나무(Pinus koraiensis Siebold et Zuccarini) 인공림에서 간벌 강도가 토양 온도, 수분, 광 유효도(photosynthetically active radiation, PAR) 및 직경 생장량 변화에 미치는 초기 영향에 대하여 알아보고자 수행되었다. 간벌은 2004년 흉고단면적($m^2$/ha)을 기준으로 45%(T45)와 60%(T60)를 제거하는 방법으로 실시되었다. 대조구, T45 및 T60의 평균 토양 온도는 각각 8.9, 10.0, $10.2^{\circ}C$, 평균 토양 수분 함량은 14.3, 16.1, 16.1%이었으며, 평균 토양 온도는 대조구 포함 각 처리구 사이에서, 평균 토양 수분 함량은 대조구와 간벌 처리구간 통계적으로 그 차이가 인정되었다(p<0.05). 대조구, T45 및 T60의 평균 PAR는 각각 44, 143, 178 ${\mu}mol/m^2$/sec로 나타나 각 처리구 간 통계적으로 유의한 차이가 인정되었다(p<0.05). 간벌 후 4년간 측정한 연평균 직경 생장량은 대조구, T45 및 T60에서 각각 0.4, 1.5, 1.2 mm으로 조사되어 간벌 처리구가 대조구에 비해 직경 생장량이 높았다. 결론적으로 간벌 후 4년이 경과한 시점에서도 토양 온도, 수분 및 임분 내 유입되는 광 유효도는 지속적으로 간벌에 의해 영향을 받는 것으로 나타났다.

• 한국습지학회지
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• 제20권2호
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• pp.116-123
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• 2018

산림생태계에서 대기로의 토양의 이동은 토양 호흡이라는 과정을 통해 이루어진다. 본 연구에서는 임령이 다른 잣나무림을 대상으로 생육기 동안의 토양 호흡값과 토양 내 뿌리의 양, 미생물 개체군 생물량을 측정하여, 토양호흡량이 임령에 따라 어떻게 다르며, 뿌리와 미생물 개체군이 얼마나 기여할 것인지 알아보고자 하였다. 토양 온도와 토양 호흡은 임령과는 상관없이 유사한 패턴을 보여 7월까지는 증가하고 이후 감소하였다. 산림의 임령이 높을수록 토양 호흡량이 대체적으로 높았다. 토양 내 뿌리와 미생물을 조사한 결과, 임령이 높을수록 토양 내 존재하는 지름 2 mm 이하인 세근의 양이 많았으며 토양 미생물 개체군의 생물량이 많았다. 토양에서 뿌리를 제거하였을 때 70년 숲은 변화가 없었으나, 40년 숲에서는 토양 호흡값이 감소하였다. 본 연구결과로 볼 때, 산림의 연령이 높아질수록 토양 호흡량이 커지며, 식물 뿌리와 특히 토양 미생물이 토양 호흡값에 많은 기여를 하고 있는 것으로 생각해 볼 수 있다.

• 농업생명과학연구
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• 제45권4호
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• pp.47-58
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• 2011

The forest of Korea had been severely degraded since early 1900s until 1950s. Korean Government has successfully accomplished the reforestation works since 1960s. However, some plantations showed poor survival and growth caused by ignoring site characteristics in selecting plantation species and lack of tending works such as thinning. The natural regeneration of indigenous species, such as Quercus species and Pinus densiflora Siebold & Zucc., were examined in the plantations of Pinus koraiensis Siebold & Zucc. and Larix kaempferi Fortune ex Gordon. Quercus species regenerated mainly by sprouting while P. densiflora regenerated naturally from a few mother trees that remained in the plantations. P. koraiensis showed poor survival ($IVI{\leq}25%$) and suppressed growth (height ${\leq}3m$ and $DBH{\leq}3cm$ at 20 year-old) by Quercus species or P. densiflora in the plantation areas, however had high survival ($IVI{\geq}70%$) and growth (8 m height and 14.1 cm DBH at 20 year-old) in areas where silvicultural practices were conducted. L. kaempferi showed good survival ($IVI{\geq}40%$) and growth (17.2 m height and 16.3 cm DBH at 30 year-old) mostly in valley areas, while it was nearly dead ($IVI{\leq}10%$) in ridge or ridge-slope areas and was replaced by indigenous species such as Quercus species ($IVI{\geq}25{\sim}55%$) or P. densiflora ($IVI{\geq}18{\sim}50%$).

• Journal of Forest and Environmental Science
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• 제21권1호
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• pp.75-82
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• 2005

이 시험 연구는 울폐된 천연활엽수림 내에 수하식재한 2-2 잣나무 묘목의 생육 성적을 평가하기 위하여 실시되었다. 식재 후 7년 동안의 생존률과 생장율에 대하여 상층 임관의 효과가 평가되었다. 7년생 잣나무 치수의 활착율은 약 80%로 조사되었으며, 평균 수고는 0.9m, 최소치는 0.3m, 최고치는 2.1m로 측정되었고, 평균 근원경은 1.7cm, 최소치는 l.4cm, 최고치는 3.5cm로 조사되었다. 개벌 후, 인공 조림한 잣나무의 생육 상황과 비교해 볼 때, 이 시험에서 수하식재된 잣나무 치수의 생육 상황은 공한지 인공 조림목에 비해서 매우 열등하여, 수고는 약 30%, 직경은 약 20%에도 미치지 못하는 것으로 파악되었다. 내음성이 있는 잣나무 치수라 할지라도 정상 생육하기에 상층의 울폐도가 너무 높다고 판단된다. 잣나무의 정상적인 생장과 발달을 위해서는 천연림 보육 작업에 준하는 벌채를 통하여 우량 활엽수를 잔존시키면서 50% 이상의 상층 임관을 열어 주어 광선 조건을 개선시켜야 할 것이다.

• The Korean Journal of Ecology
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• 제11권2호
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• pp.83-95
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• 1988

Phytomass, annual net production, respiration, annual gros production and litter fall were estimated in young Korean pine (Pinus koraiensis) plantations reforested 1,2,3,6,9 and 11 years ago, respectivly. The estimated phytomasses in terms of allometry were 0.07, 0.44, 0.58, 13.37, 32.26 and 48.42ton/ha/yr for annual net production and those of understory with harvest method were 3.70, 4.52, 5.28, 6.72, 7.56 and 5.72ton/ha for standing phytomass and 5.01, 4.71, 5.52m 6.15, 4.51 and 2.08 ton/ha/yr for annual net production at 1,2,3,6,9 and 11 year old plantation, respectively. Although the standing phytomass of understory increased gradually until 9 years thereafter decreased, that of white pine increased suddenly from 6 years after reforestation. The ratios of the annyal net production of understory to that of white pine were 71.57, 1.48 and 0.23 at 1,6 and 11 year old plantations, respectively. The net production in calorie value for whole vegetation of the plantations, respectively. The net production in calorie value for whole vegetation of the plantations increased until 9 years thereafter decreased; i.e. 224, 221, 280, 466, 527 and 494X105 kcal/ha/yr at 1,2,3,6,9 and 11 year old plantation, respectivey. The ratio of annual net production to annual gross production of the undersoty was lower than that of the pine at the same plantation age. Efficiency of solat energy untilization for net production by the pine was lower than that by understory y\until six ear old plantation but that was vice versa over 9 year old plantation. That for gross producrion by the pine was lower than that by the unsersotry at all plantations.

• 한국산림과학회지
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• 제79권4호
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• pp.431-434
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• 1990

잣나무의 계절적학(季節的學) 생장과정(生長過程)을 알아보기 위하여, 15년생(年生) 잣나무 고립목(孤立木)의 눈(芽), 신초(新梢), 침엽(針葉)의 생장(生長) 패턴을 조사(調査)하였고, 간벌(間伐)이나 지타(枝打)를 실시하지 않은 28년생(年生) 잣나무림의 낙엽량(落葉量)과 세근량(細根量)의 계절별(季節別) 변화(變化)를 조사(調査)하였다. 신초(新梢)는 4월(月) 12일(日) 부터 생장(生長)을 시작하여 6월(月) 7일(日)에 생장(生長)을 정지(停止)하였는데 이 때가 눈이 형성(形成)되는 시기(時期)이다. 신엽(新葉)은 5월(月) 10일(日) 부터 생장(生長)을 시작(始作)하여 7월(月) 19(日)에 생장(生長)을 정지(停止)하였는데 이 때는 눈이 신장(伸張)되는 시기(時期)였다. 낙엽시기(落葉時期)는 대부분 10월중(月中)이었으며 7월(月)과 8월(月)에도 폭풍우에 의하여 일부 낙엽(落葉)이 되었다. 세근(細根)의 생장(生長)은 가을에 대부분(大部分) 이루어 졌으며(1,004 kg/ha), 세근(細根)의 고사(枯死)는 겨울(583 kg/ha)과 봄(1,331 kg/ha)에 대부분(大部分) 발생(發生)하였다.