• 한국환경농학회지
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• 제30권3호
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• pp.229-233
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• 2011

BACKGROUND: Soil acidification, which is known to be one of the reasons of forest decline, is associated with decreases in exchangeable Ca and increases in Al concentration, leading to low Ca/Al ratio in soil solution. As tree rings are datable archives of environmental changes, Ca/Al ratios of annual growth ring may show decreasing pattern in accordance with the progress of soil acidification. This study was conducted to investigate Ca/Al pattern of Pinus densiflora tree ring in an attempt to test its usefulness as an indicator of historical soil acidification. METHODS AND RESULTS: Three P. densiflora tree disks were collected from P. densiflora forests in Jeonnam province, and soil samples (0-10, 10-20, and 20-30 cm in depth) were also collected from the tree locations. Soils were analyzed for pH and exchangeable Ca and Al concentrations, and Ca/Al was calculated. Annual growth rings formed between 1969 and 2007 were separated and analyzed for Ca/Al. Soil Ca/Al was positively (P<0.01) correlated with soil pH, suggesting that soil acidification decreased Ca while increasing Al availability, lowering Ca/Al in soil solution. The Ca/Al of tree rings also showed a decreasing pattern from 18.2 to 5.5 during the period, and this seemed to reflect historical acidification of the soils. CONCLUSION(s): The relationship between soil pH and Ca/Al and the decreasing pattern of Ca/Al of tree ring suggest that Ca/Al of tree ring needs to be considered as a proxy of the progress of soil acidification in P. densiflora forest in southern Korea.

• The Korean Journal of Ecology
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• 제18권1호
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• pp.189-201
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• 1995

In order to clarify regeneration processes and mechanisms of the disturbed Pinus densiflora forest, responses of Pinus densiflora to gap formed by disturbance were analysed by growth of saplings and mature and growth equations were obtained from branch growth of mature trees and height growth of saplings, and age distribution of saplings and young trees recruited within gap was analysed in relation to gap age. Height growth of saplings within gaps was accelerated after gap formation. Such abrupt increases of growth of saplings after the gap formation might be resulted in the difference of growth of saplings between gap and non-gap areas. In fact, height and diameter of saplings in the central part of gap were larger than those of saplings in marginal parts of gap and non-gap area. However, density of saplings was not different in both parts. In addition, growth of annual rings of mature trees bordering on gap also increased after gap formation. Branch growth of mature trees bodering on gap was 6.3 - 6.5 cm /year and the mean radius of gaps created by death of only one canopy tree was about 3 m. Therefore, for those gaps to be closed by branch growth it will take 46 years. Growth of saplings within gap showed exponential equation. Fifty years will be required for the saplings to enter the forest canopy by the exponential growth equation. Therefore, gap created by only one tree might be closed by branch growth of surrounding canopy trees in advance of being done by height growth of saplings. But gaps created by death of trees more than 2 will be closed by the growth of saplings. Among the regenerating saplings and young trees within gaps, individuals established in advance of gap formation were more than those established after the gap formation. From these results, it was assumed that the disturbed Pinus densiflora forests in these sites were regenerated by height growth of saplings recruited in advance of gap formation.

• 생물환경조절학회지
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• 제16권3호
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• pp.217-221
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• 2007

다양한 활엽수 자원의 개발에 필요한 기초자료를 제공하고자 쪽동백나무 유묘의 생육밀도에 따른 물질생산량과 생장특성 등 최적의 생장조건을 조사하였다. 묘목의 생육밀도는 수고생장에 크게 영향을 미치는 중요한 요인이 될 수 있으며, 본 실험 결과 쪽동백나무의 $1m^2$당 생육 밀도에 따른 묘목의 생장은 49본구에서 간장과 근원직경이 우수한 생장량을 보인반면 생육밀도가 낮은 처리구는 근원직경 생장이 증가하면서 간장생장은 떨어지는 경향을 보였다. 물질생산량 또한 생장 특성과 마찬가지로 $1m^2$당 49본구 처리구에서 전체 물질생산량이 통계적으로 유의적인 차이를 보이면서 $3.12{\pm}0.80g$로 다른 처리구보다 높은 물질생산량을 보였고, T/R율에서도 1.59로 나타났다. 생리적 특성으로 광합성률 또한 쪽동백나무의 경우 $1m^2$당 $49/m^2$ 본구와 $64/m^2$ 본구에서 상대적으로 높은 광합성률을 보였고 밀도가 높아질수록 광합성 효율이 떨어지는 결과를 나타냈다. 이는 생육 환경조건에서 적절한 공간 확보가 궁극적으로 최종 물질대사 작용인 광합성률 변화에서 최적의 상태를 보이면서 생리적으로 안정된 생장형태를 보이는 것으로 판단되며, 적정 공간의 장애가 실질적인 생장저하를 발생시키고, 궁극적으로 물질대사의 최고 단계인 광합성효율 또한 낮아지는 경향을 나타냈다.

• 한국조경학회지
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• 제26권2호
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• pp.207-218
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• 1998

A site survey in two apartment complexes and a nursery experiment were carried out in this study to provide basic data of the long-pending growth characteristics of major landscaping trees, such as Picea abies, Pinus parviflora, Metasequoia glyptostroboides, Magnolia denudata, Acer buergerianum and Acer palmatum. According to the main results, the survival rates were very low, reflected by the average survival rate of the four species was 95% at the nursery site. And, it was presumed that the site conditions of two apartment complexes for tree growth were very inferior to those of the nursery site, taking into consideration that the increment percents of growth factors of the tree species at the nursery site were relatively higher than those of the apartment complexes. The distribution patterns of the current growth factors of trees showed a normal distribution. The regression equation of breast diameter on diameter at root collar showed especially high predictability. And, it was thought that the most critical limiting environmental factors on tree growth at the apartment complexes were found to be alkaline pH caused by excessive Ca, high percent base saturation, insufficiency of available moisture content, bad drainage due to inferior soil texture, high soil hardness, lack of organic matter and shortage of cation exchange capacity in soil.

• ETRI Journal
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• 제31권2호
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• pp.240-242
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• 2009

A computationally efficient implementation of the progressive edge-growth algorithm is presented. This implementation uses an array of red-black (RB) trees to manage the layered structure of check nodes and adopts a new strategy to expand the Tanner graph. The complexity analysis and the simulation results show that the proposed approach reduces the computational effort effectively. In constructing a low-density parity check code with a length of $10^4$, the RB-tree-array-based implementation takes no more 10% of the time required by the original method.

• 한국환경복원기술학회지
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• 제14권2호
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• pp.1-10
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• 2011

Six pine trees (Pinus densiflora S. et Z.) at the Euilimji Lake Park in Jecheon were collected to investigate tree ages, growth decline pattern and the years of death. Tree-ring measurement was carried out using the Lintab with a resolution of 0.01mm. Tree age were 80-176 years. Cross-dating between the tree-ring series of each tree and the local chronology from Worak Mountain resulted that four and two trees died in 1998 and 1999, respectively. Three dead trees had only formed earlywood in the outermost tree ring and the others had incomplete latewood. Therefore, it was proven that the former trees died between spring and early summer, whereas the later ones died during late summer and/or autumn. The simultaneous deaths of trees suggest the insect damage and/or drought may be the crucial reason of the death, but frequent reaction woods, which were formed by leaning stem, and scars formed by physical damage may also contribute to the death.

• 한국자원식물학회지
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• 제36권1호
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• pp.91-99
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• 2023

기후변화 대응 바이오매스 생산이 우수한 활엽수 경제 조림수종 개발에 대한 수요가 증가하고 있다. 아까시나무는 탄소흡수능이 우수한 속성수로서 국내 적응성이 뛰어나고 경제적, 환경적 기능이 우수하다. 본 연구는 비교선발법을 이용하여 용재수로서 가치가 높은 아까시나무 우량개체 64본을 선발하였다. 경기, 강원, 충청, 경상 등 4개 지역으로 나누어서 생장특성을 비교한 결과 선발목들은 비교목들에 비해 수고, 흉고직경, 지하고, 통직성에서 유의적으로 우수한 형질을 보였다. 특히 충청지역의 선발목들이 가장 우수한 생장특성을 나타냈으며, 임분별로는 고성, 천안, 안동 집단이 우량집단으로 나타났다. 생장에 영향을 주는 요인 중에서 토양 성분은 상관관계가 없었으며, 대단위 산림 조림 지역 혹은 호수와 저수지가 인접한 지역의 선발목이 수고 생장이 우수한 것으로 나타났다.

• 한국환경생태학회지
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• 제36권3호
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• pp.338-349
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• 2022

다양한 수종의 묘목을 고밀도로 심는 모듈군락식재가 기존의 성목식재보다 자연림 복원 효과성이 뛰어난지 알고자 야외 실험을 했다. 또 모듈군락식재의 식재밀도 차이에 따라 생장이 촉진되는지, 또 식피율이 높아지는지를 알아보았다. 큰나무를 넓게 띄어 심는 성목식재구(대조구)와 다종의 묘목을 고밀도로 심는 모듈군락식재구(처리구)로 구분했고, 다시 식재밀도에 따른 3주/m²와 1주/m² 모듈군락식재구로 나눠 실험을 설계했다. 2019년 5월부터 26개월간 공시재료의 생존율, 생장량(수고, 수관폭, 근원직경), 식피율을 측정했고, 측정 수고값을 활용하여 장래 수고생장을 예측했다. 모듈군락식재구의 생존율과 상대생장량이 성목식재구보다 높았다. 모듈군락식재구의 식피율은 23개월 이전에 지표면을 완전히 덮었지만, 성목식재구는 이식스트레스로 인해 오히려 식피율이 낮아졌다. 고밀도로 심은 모듈군락식재구의 묘목이 자라서 식재 후 5~6.5년 만에 성목식재구보다 더 높이 자랄 것으로 예측됐다. 이런 결과를 이끈 원인은 다종(多種)·묘목·고밀도 식재와 토양개량·멀칭 등의 식재기반 개선 때문이라 본다. 즉, 모듈군락식재구에 심은 묘목은 큰나무를 심은 성목식재구보다 식재 후 환경 적응력이 뛰어나 생존율이 높고, 초기 생장량이 많았을 것이다. 다양한 자생수종의 고밀도 혼식은 상호보완적 환경압을 완화하는 동시에 개체간 경쟁을 유발해 생장 촉진을 이끌었다. 더불어, 식재기반 개선은 묘목의 활착율 상승과 생장량 증가에 유효했다고 본다. 식재밀도가 높을수록 식피율이 급격히 늘어나, 제초 등의 사후관리비 절감 효과가 있을 것이다. 모듈군락식재구(3주/m², 1주/m²)의 식재밀도가 높았을 때 수고생장이 촉진되었고, 수관폭·근원직경은 식재밀도가 낮았을 때 높아지는 경향을 보였지만, 통계적 차이가 없었다.

• 한국대기환경학회지
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• 제13권4호
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• pp.249-256
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• 1997

To identify the long-term influence of acid rain treatment on tree growth, acid rain of various composition (pH 2.0, pH 4.0 and pH 5.6 as control) was applied to several landscape trees for five months (April through August, 1991). Tree height, pH values and $Al^{3+}$ concentration in soil were investigated. Acid rain treatments seemed to promote height growth in the first year (1991), but have become an inhibiting factor over five years. All of coniferous species and most broad-leaved species, except Acer ginnala, showed opposite trends in height responses to acid rain treatments between the first (1991) and last (1996) year. In contrast, Acer ginnala showed similar trends to acid rain treatments in the height growth between 1991 and 1996. This result suggested that Acer ginnala has a characteristic adapability to acid rain stress. pH values of surface soil were lower than those of 30 cm soil depth. This fact suggested that acid rain treatments made surface soil acidic condition. In addition, physiological characteristics (photosynthesis, stomatal condition and biomass) have to be investigated to identify the relationship between long-term effects of $AL^{3+}$ concentration and growth.

• 한국산림과학회지
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• 제104권1호
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• pp.76-83
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• 2015

본 연구는 경남에 자생하고 있는 100-600년 추정 노거수 및 보호수 왕버들의 생육특성을 분석하고, 상토에 따른 삽목증식의 영향을 구명하였다. 노거수 및 보호수 왕버들 6개체는 마을형 4개소, 하천형 주변 1개소, 들판형 1개소에 자생하고 있었다. 삽목증식은 10가지 상토에서 실시하였으며, 모든 상토에서 삽목묘의 생존율은 93%이상이었다. 삽목묘의 묘고 생장이 가장 좋았던 상토는 시판 바이오상토(CBS, mean=60.01 cm)였으며, 다음으로 혼합상토(VPMP, mean=42.95 cm), 피트모스(PM, mean=41.81 cm) 순이었다. 근원경의 생장은 상토에 따라 심한 차이를 보였으며, 신초는 1-4개 형성되었다. 삽목묘의 뿌리길이는 묘고 생장이 좋았던 상토였던 CBS와 VPMP에서 20 cm 이상 생장하였다. 상토의 물리화학적 특성을 조사한 바, 왕버들의 삽목에는 보습력과 통기성이 양호하며, EC값이 높은 약산성의 상토가 적합한 것으로 나타났다. CBS와 VPMP 상토는 노거수 및 보호수 왕버들의 삽목증식에 적합한 상토로 나타났다.