• 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.

• The Korean Journal of Ecology
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• 제24권4호
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• pp.213-217
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• 2001

The purpose of this study is to investigate the effects of hardwood competitions in stand structure and dynamics by applying prediction models for unthinned loblolly pine (Pinus taeda L.) plantations. A parameter recovery procedure for the Weibull distribution function based on four percentile equations was applied to develop diameter distribution prediction models. Four percentiles of the cumulative diameter distribution prediction equations were predicted as a function of quadratic mean diameter plus competin hardwood trees perhectare varibales. According to the results of this study. it was found that as the amount of competing hardwood trees increased, diameter distributions in terms of stand structure dynamics tended to be more skewed to the right. Therefore, the influence of non-planted hardwood trees interspecific competitoin on planted loblolly pines showed negative effects on the stand structure and dynamics.

• 영미문화
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• 제10권2호
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• pp.127-147
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• 2010

In Faulkner's many works, most Mulattoes are represented as tragic characters who feel confused with their racial identity and are sacrificed by the Southern racism in the end. However, in Go Down, Moses Lucas Beauchamp is an exceptional mulatto in that he survives the Southern racism and achieves some dignity as a human. It is because he maintains the relationship with his family and environment as a skilled farmer. Although Southerners idealized their lives in plantations as nature-friendly and ecological way of life, plantation owners had little direct relationship with land as plantations were cultivated by black slaves' labor. Therefore, white landowners had little knowledge about cultivation and ecological awareness. Although Lucas Beauchamp is criticized as he has the strong will to power and patriarchal attitude, it is partly caused from endeavor to overcome the suppression as a black male whose masculinity is denied in the Southern society. In spite of his limitation, he shows the possibility to escape from the curse prevailing in the South, which abuses land and other races through the relationship with others and land. He has positive aspects in that he has genuine relationship with land and others and takes his responsibility for others, searching the most suitable way to survive as a black.

• Journal of Forest and Environmental Science
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• 제37권1호
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• pp.25-34
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• 2021

This study was conducted at Sitakunda coastal afforestation range, comprised of four beats- Bansbaria, Bakkhali, Baterkhil and Bogachattar, in Chittagong. Afforestation effects on soil physicochemical properties in comparison to adjacent barren land were analysed. In the study area, an area of 3277.33 ha was planted with Sonneratia apetala, Avecinnia officinalis, Excoecaria agallocha, Bruguiera sexangula, Ceriops decandra from 1968 to 2011. We found positive soil physicochemical changes in plantations in comparison to adjacent barren land. Soil bulk density of plantation was lower than the adjacent barren land. Soil pH and soil salinity were significantly higher in barren land whereas soil organic matter, organic carbon, nitrogen, phosphorus, potassium of plantations were higher in afforested land. Soil texture ranged from clay loam to sandy loam in different depth of these two types of land. However, this study concludes that there is clear evidence that afforestation has positive impacts on all soil properties in different location and soil depths in the study area.

• Journal of the Korean Wood Science and Technology
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• 제49권2호
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• pp.191-209
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• 2021

Australia has significant wood resources in its native forest, but the resource available for harvest becomes lesser due to the conversion of native forest to conservation reserves. The natural occurrences of bushfires, droughts, and cyclones are highly destructive, making the situation worse. The shortage of wood resources is having a significant negative impact on Australia because wood is so scarce that they cannot meet domestic demands, especially durable wood. Australia cleared approximately 100 million hectares of its land to establish forest plantations, and two million trees were planted. However, most of these plantations are for pulpwood production; however, their application for high-value products is limited due to their undesirable properties. Wood modification is a process of improving unfavorable wood properties to be utilized for a wide range of applications. Australia has not adopted any of these modification processes; it still depends on the less toxic wood preservative to treat wood. This study focuses on the recent advancement in industrial wood modification worldwide and how it may be used to modify Eucalyptus wood for high-value applications. The opportunities and suggestions for Eucalyptus wood modification in Australia will be discussed. Before the study concludes, the future of commercial wood modification for Eucalyptus plantation in Australia will also be presented.

• 대한원격탐사학회지
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• 제39권1호
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• pp.99-110
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• 2023

Land surface temperature (LST) is a critical environmental indicator affected by land cover (LC) changes. Currently, the most convenient and fastest way to retrieve LST is to use remote sensing images due to their continuous monitoring of the Earth's surface. The work intended to investigate land cover change and temperature response inAn-Najaf province. Landsat multispectral imageries acquired inAugust 1989, 2004, and 2021 were employed to estimate land cover change and LST responses. The findings exhibited an increase in water bodies, built-up areas, plantations, and croplands by 7.78%, 7.27%, 6.98%, 3.24%, and 7.78%, respectively, while bare soil decreased by 25.27% for the period (1989-2021). This indicates a transition from barren lands to different land cover types. The contribution index (CI) was employed to depict how changes in land cover categories altered mean region surface temperatures. The highest LSTs recorded were in bare lands (42.2℃, 44.25℃, and 46.9℃), followed by built-up zones (41.6℃, 43.96℃, and 44.89℃), cropland (30.9℃, 32.96℃, and 34.76℃), plantations (35.4℃, 36.97℃, and 38.92℃), and water bodies (27.3℃, 29.35℃, and 29.68℃) respectively, in 1989, 2004, and 2021. Consequently, these changes resulted in significant variances in LST between different LC types.

• 한국환경과학회지
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• 제32권3호
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• pp.161-171
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• 2023

The present study evaluated growth factors affecting oak community plantations through literature review and a field survey. Specifically, 41 related literature sources were analyzed and field surveys were conducted to collect growth data. Previous studies were analyzed to identify variables with high frequency of use. The frequency of use was in the order of tree size > environment > planting density > forest age. Analysis of factors impacting height and diameter growth revealed that the growth rate of species other than Quercus variabilis was negative in the field survey. This may be because of differences between the actual trees planted and specifications in the construction drawings, which may be attributed to the site conditions and decisions made by the project subject during construction. Furthermore, simple linear regression analysis was conducted with time, height at planting, density, and species code as the independent variables and growth rate as the dependent variable. A strong positive linear correlation was noted between height and diameter. This work builds a foundation for developing a forest restoration model and simulation program based on a regression model derived from the four variables tested.

• 임산에너지
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• 제23권1호
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• pp.1-18
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• 2004

본 연구는 질소 및 인 시비가 지상부 생체량과 양분의 분포에 미치는 영향을 조사하기 위하여 경기도 양평지역의 유사한 토양 위에 조성되어 있는 41년생 리기다소나무와 낙엽송 조림지를 대상으로 실시되었다. 시비는 대조구(control), 저농도 시비구 [200N kg/ha+25P kg/ha(LNP)], 고농도 시비구 [400N kg/ha+50P kg/ha(HNP)] 등 세 수준으로 처리하였으며, 본 연구로부터 얻어진 결과는 다음과 같다. 리기다소나무와 낙엽송 임분의 총 지상부 생체량은 대조구가 149, 145ton/ha, LNP 처리구가 166, 149ton/ha, HNP 처리구가 152, 170ton/ha이었으며, 수종간에는 유의적인 차이가 나타나지 않았다. 리기다소나무와 낙엽송 임분 모두 지상부 각 부위별 생체량은 수간목부>가지>수피>엽의 순으로 분포되어 있었다. 하층식생의 생체량은 리기다소나무림이 1,111kg/ha, 그리고 낙엽송림이 907kg/ha이었으며, 이는 전체 지상부 생체량의 0.6～0.7%에 해당되는 것이었다. 일반적으로 수체 내 모든 양분들의(N, P, K, Ca, Mg) 농도는 리기다소나무에 비해 낙엽송이 높았는데, 그 이유는 낙엽성 침엽수가 상록성 침엽수에 비해 높은 양분 흡수력을 가지고 있기 때문으로 판단된다. 리기다소나무와 낙엽송 임분의 각 부위별 양분농도는 처리간에는 유의적인 차이가 나타나지 않은 반면, 수종간 각 부위간에는 고도의 유의적인 차이가 있는 것으로 나타났다. 또한 두 수종 모두 각부위별 양분농도는 엽>가지>수피>수간목부의 순으로 감소되었다. 두 수종 모두 양분함량은 시비처리구가 대조구에 비해 많았으며, 리기다소나무는 LNP 처리구에서 그리고 낙엽송은 HNP 처리구에서 가장 많았던 것으로 나타났다. 지상부 식생에 대한 총 양분함량은(N+P+K+Ca+Mg) 리기다소 나무가 703kg/ha 그리고 낙엽송이 869kg/ha였다.

• 한국산림과학회지
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• 제113권1호
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• pp.97-106
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• 2024

낙엽·낙지에 의한 탄소 및 질소 유입의 정량화는 산림생태계 양분순환 기작의 이해나 산림생산력 증진을 위한 토양양분관리에 중요하다. 본 연구는 서로 인접한 지역에 식재된 동일 영급의 삼나무와 편백 조림지를 대상으로 낙엽트랩을 설치한 후 2020년 12월부터 2021년 12월까지 낙엽·낙지에 의한 탄소 및 질소유입량을 3개월 단위로 조사하였다. 낙엽·낙지량은 꽃, 구과, 종자 같은 생식기관을 제외하고 수종 간 차이가 없었으며, 계절별로는 12월에서 3월에 유입량이 가장 많았다. 낙엽·낙지 중 편백 잎(낙엽)과 종자의 탄소농도는 삼나무에 비해 유의적으로 높았으며 낙엽과 꽃의 탄소농도는 계절별 변동을 보였다. 한편 낙엽의 질소농도도 계절별 변동을 보여 하절기(6월~9월)의 질소농도(삼나무 0.96%, 편백 1.01%)는 타 계절(삼나무 0.43%, 편백 0.53%)에 비해 유의하게 높았다. 수종별 질소농도는 삼나무 구과가 편백에 비해 높은 값을 보였다. 낙엽·낙지 중 낙엽에 의한 탄소 및 질소유입량은 두 수종 모두 12월~3월에 가장 많았으며, 6월~9월은 가장 적게 유입되었다. 연 탄소유입량은 삼나무 조림지 3,054 kg C ha^-1 yr^-1, 편백 조림지 3,129 kg C ha^-1 yr^-1로 두 수종 사이에 차이가 없었다. 연 질소유입량은 삼나무 조림지의 생식기관에 의한 질소유입량이 편백에 비해 크게 나타나 삼나무가 46.93 kg N ha^-1 yr^-1로 편백의 25.17 kg N ha^-1 yr^-1에 비해 약 1.9배 많았다. 본 연구 결과는 삼나무와 편백 조림지에 낙엽·낙지를 포함한 임분 단위 탄소 및 질소순환을 예측하는데 기초자료로 활용될 것으로 기대된다.

• 한국산림과학회지
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• 제86권2호
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• pp.119-127
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• 1997

본 연구(硏究)는 태백산맥(太白山脈) 주위(周圍)에 분포(分布)하는 형질(形質)이 우수(優秀)한 소나무를 전국적(全國的)으로 확대(擴大) 조림(造林)할 수 있는 가능성(可能性)을 알아보기 위하여 수행(遂行)하였다. 경북(慶北) 천진(薦珍) 등(等) 6개(個) 천영임분(天然林分)에서 채종(採種)된 종자(種子)를 양묘(養苗)하여 1987년(年) 4월(月) 충남(忠南) 태안(泰安) 등(等) 8개(個) 지역(地域)에 1-1묘(苗)를 난괴법(亂塊法) 3반복(反復)으로 식재(植栽)하였다. 생장조사(生長調査)는 식재(植栽) 후(後) 2, 4년생(年生)일때 수고생장(樹高生長)을, 6년생(年生)일 때 수고(樹高)와 근원경(根元徑)을 조사(調査)하였다. 식재(植栽) 후(後) 2, 4, 6년생(年生)의 수고생장(樹高生長)은 시험간(試驗地間)에 많은 차이(差異)가 있었고, 6년생(年生) 수고생장(樹高生長)과 시험지(試驗地)의 위도(緯度), 토양중(土壤中)의 치환성(置換性) 인산, 칼륨, 칼슘함량(含量)과는 정(正)의 상관관계(相關關係)가 있었으며 경도(經度), 표고(標高)와는 부(負)의 상관관계(相關關係)가 있었다. 또한 수고생장(樹高生長)은 산지간(産地間)에 많은 차이(差異)를 보였으며, 6년생(年生) 수고생장(樹高生長)이 가장 우수(優秀)한 봉화산(奉化産)은 전(全) 산지(産地) 평균(平均)보다 16% 더 좋은 생장(生長)을 하였고, 가장 저조(低調)한 경주산(慶州産)은 전(全) 산지(産地) 평균(平均)보다 11% 더 저조(低調)한 생장(生長)을 하였으며, 소나무 산지간(産地間) 생장(生長) 양상의 차이(差異)가 있어 태백산맥(太白山脈) 주위(周圍)에 분포(分布)하는 형질(形質)이 우수(優秀)한 소나무, 일명 강송(剛松)을 전(全) 지역(地域)에 식재(植栽)할 수 있다는 가능성을 보였다.