• Asian-Australasian Journal of Animal Sciences
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• 제12권7호
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• pp.1015-1018
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• 1999

Single trait mixed models have been dominantly utilized for genetic evaluation of the reproductive traits in swine. However employing multiple trait approach may lead to more accurate genetic evaluations. For 5 litter size and litter weight traits of Danish Landrace, genetic parameters were estimated with a multiple trait mixed model. The heritability estimates were 0.02, 0.03, 0.03, 0.05, and 0.07, respectively for litter size at birth, litter size born alive, litter weight at birth, litter size at weaning, and litter weight at weaning. Negative genetic correlations were all positive. The litter weight at birth showed genetic antagonism with litter size born alive (-0.65) and litter size at weaning (-0.31), but positive with litter size at birth (0.47) and litter weight at weaning (0.31). The estimates of environmental correlations were larger than their corresponding genetic correlation estimates except for those between litter weight at birth and the other four traits. This study recommends simultaneous selection for two or more traits with multivariate mixed models in order to improve overall economic response.

• Journal of Forest and Environmental Science
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• 제29권1호
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• pp.38-48
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• 2013

Decomposition of plant material is an important component in the study of forest ecosystem because of its critical role in nutrient cycling. Different tree species has different nutrient release patterns, which are related to leaf litter quantitative traits and seasonal environmental factors. The quantitative traits of leaf litter are important predictors of decomposition and decomposition rates increase with greater nutrient availability in the forest ecosystems. At the ecosystem level, litter quantitative traits are most often related to the physical and chemical characteristics of the litter, for example, leaf toughness and leaf mass per unit area, and lignin content tannin and total phenolics. Thus, the analysis of litter quantitative traits and decomposition are highly important for the understanding of nutrient cycling in forest ecosystems. By studying the role of litter quantitative traits on decomposition and nutrient cycling in forest ecosystems will provide a valuable insight to how quantitative traits influence ecosystem nutrient dynamics. Such knowledge will contribute to future forest management and conservation practices.

• Journal of Ecology and Environment
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• 제44권2호
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• pp.81-89
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• 2020

In the forest ecosystems, litterfall is an important component of the nutrient cycle that regulates the accumulation of soil organic matter (SOM), the input and output of the nutrients, nutrient replenishment, biodiversity conservation, and other ecosystem functions. Therefore, a profound understanding of the major processes (litterfall production and its decomposition rate) in the cycle is vital for sustainable forest management (SFM). Despite these facts, there is still a limited knowledge in tropical forest ecosystems, and further researches are highly needed. This shortfall of research-based knowledge, especially in tropical forest ecosystems, may be a contributing factor to the lack of understanding of the role of plant litter in the forest ecosystem function for sustainable forest management, particularly in the tropical forest landscapes. Therefore, in this paper, I review the role of plant litter in tropical forest ecosystems with the aims of assessing the importance of plant litter in forest ecosystems for the biogeochemical cycle. Then, the major factors that affect the plant litter production and decomposition were identified, which could direct and contribute to future research. The small set of studies reviewed in this paper demonstrated the potential of plant litter to improve the biogeochemical cycle and nutrients in the forest ecosystems. However, further researches are needed particularly on the effect of species, forest structures, seasons, and climate factors on the plant litter production and decomposition in various types of forest ecosystems.

• Journal of Ecology and Environment
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• 제34권4호
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• pp.401-410
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• 2011

We assayed the effects of simulated acid rain on the mass loss, $CO_2$ evolution, dehydrogenase activity, and microbial biomass-C of decomposing Sorbus alnifolia leaf litter at the microcosm. The dilute sulfuric acid solution composed the simulated acid rain, and the microcosm decomposition experiment was performed at 23$^{\circ}C$ and 40% humidity. During the early decomposition stage, decomposition rate of S. alnifolia leaf litter, and microbial biomass, $CO_2$ evolution and dehydrogenase activity were inhibited at a lower pH; however, during the late decomposition stage, these characteristics were not affected by pH level. The fungal component of the microbial community was conspicuous at lower pH levels and at the late decomposition stage. Conversely, the bacterial community was most evident during the initial decomposition phase and was especially dominant at higher pH levels. These changes in microbial community structure resulting from changes in microcosm acidity suggest that pH is an important aspect in the maintenance of the decomposition process. Litter decomposition exhibited a positive, linear relationship with both microbial respiration and microbial biomass. Fungal biomass exhibited a significant, positive relationship with $CO_2$ evolution from the decaying litter. Acid rain had a significant effect on microbial biomass and microbial community structure according to acid tolerance of each microbial species. Fungal biomass and decomposition activities were not only more important at a low pH than at a high pH but also fungal activity, such as $CO_2$ evolution, was closely related with litter decomposition rate.

• Journal of the Korean Wood Science and Technology
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• 제48권5호
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• pp.591-607
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• 2020

This study was aimed to investigate the changes of chemical composition of the volatile organic compounds (VOCs) emitted from red pine needles in the process of needle abscission or senescence. The VOCs in intact, senescent, and litter red pine needle samples were analyzed by headspace-solid phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC/MS). And then, multivariate statistical interpretation of the processed data sets was conducted to investigate similarities and dissimilarities of the needle samples. Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were used to investigate the dataset structure and discrimination between samples, respectively. From the data preview, the levels of major components of VOCs from needles were not significantly different between needle samples. By PCA investigation, the data reduction according to classification based on the chlorophyll a / chlorophyll b (Ca/Cb) ratio were found to be ideal for differentiating intact, senescent, and litter needles. The following OPLS-DA taking Ca/Cb ratio as y-variables showed that needle samples were well grouped on score plot and had the significant discriminant compounds, respectively. Several compounds had significantly correlated with Ca/Cb ratio in a bivariate correlation analysis. Notably, the litter needles had a higher content of oxidized compounds than the intact needles. In summary, we found that chemical compositions of VOCs between intact, senescent, and litter needles are different each other and several compounds reflect characteristic of needle.

• 한국환경생태학회지
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• 제32권1호
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• pp.23-29
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• 2018

월악산 국립공원에서 2009년 1월부터 2013년 12월까지 5년간 낙엽생산량과 낙엽을 통해 임상으로 이입되는 영양염류량을 조사하였다. 잎, 가지, 생식기관, 기타로 분류된 낙엽의 5년간 평균 생산량은 각각 $1.940{\pm}0.21$, $0.505{\pm}0.15$, $0.259{\pm}0.09$, and $0.737{\pm}0.14t\;ha^{-1}yr^{-1}$ 이었으며 낙엽구성원의 비율은 각각 56.4, 14.7, 7.5, 21.4%, 로 잎의 비율이 가장 높았다. 조사기간 동안 생산된 낙엽의 총량은 2009년부터 2013년까지 각각 2.810, 3.796, 3.268, 3.284, $4.045ton\;ha^{-1}yr^{-1}$ 으로, 5년간 평균 $3.441{\pm}0.4ton\;ha^{-1}yr^{-1}$의 낙엽이 생산되었다. 조사기간 동안 조사된 낙엽을 통해 입상에 이입되는 질소, 인, 칼륨, 칼슘, 마그네슘의 평균 이입량은 각각 $22.73{\pm}4.92$, $1.05{\pm}0.42$, $4.26{\pm}1.69$, $8.48{\pm}4.62$, $2.42{\pm}1.01kg\;ha^{-1}yr^{-1}$ 이었다.

• Journal of Ecology and Environment
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• 제30권1호
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• pp.63-68
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• 2007

Litter production, nutrient contents of each component of litterfall and amount of nutrients returned to forest floor via litterfall were investigated from May 2005 through April 2006 in Quercus mongolica, Quercus variabilis and Pinus densiflora forests at Mt. Worak National Park. Total amount of litterfall during one year in Q. mongolica, Q. variabilis and P. densiflora forests was 542.7, 459.2 and $306.9\;g\;m^{-2}\;yr^{-1}$, respectively. Of the total litterfall, leaf litter, branch and bark, reproductive organ and the others occupied 50.3%, 22.7%, 10.1 % and 16.9% in Q. mongolica forest, 81.9%, 7.2%, 3.1% and 7.9% in Q. variabilis forest, 57.4%, 12.8%, 5.6% and 24.1 % in P. densiflora forest, respectively. Nutrients concentrations in oak litterfall were higher than those in needle litter. N, P, K, Ca and Mg concentration in leaf litterfall were 13.8, 1.1, 7.2, 4.2 and 1.3 mg/g for Q. mongolica forest, 10.5, 0.7, 3.2, 3.7 and 1.6 mg/g for Q. variabilis forest, 5.3, 0.4, 1.2, 2.8 and 0.6mg/g for P. densiflora forest, respectively. The amount of annual input of N, P, K, Ca and Mg to the forest floor via litterfall was 43.36, 2.89, 21.38, 23.31 and $5.62\;kg\;ha^{-1}\;yr^{-1}$ for Q. mongolica forest, 32.28, 2.01, 10.23, 20.29 and $7.78\;kg\;ha^{-1}\;yr^{-1}$ for Q. variabilis forest, 15.80, 1.04, 3.99, 9.70 and $2.10\;kg\;ha^{-1}\;yr^{-1}$ for P. densiflora forest, respectively.

• 환경생물
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• 제27권3호
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• pp.261-265
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• 2009

월악산 국립공원 내의 소나무군락에서 2005년 5월부터 2008년 4월까지 3년 동안 월별 낙엽의 생산량과 낙엽을 통해 임상에 이입되는 영양염류의 양을 조사하였다. 2005, 2006, 2007년의 낙엽생산량은 각각 3.070, 3.066, 3.099 ton $ha^{-1}yr^{-1}$이었으며, 3년 동안의 평균 낙엽생산량은 $3.078{\pm}0.018\;ton\;ha^{-1}yr^{-1}$이었다. 낙엽 구성원 중 침엽, 가지 및 수피, 생식기관 그리고 기타가 차지하는 비율은 각각 61.9, 10.4, 5.2, 22.5%으로 침엽이 차지하는 비율이 가장 컷다. 조사지소에서 3년 동안 낙엽을 통해 임상에 이입되는 질소, 인, 칼륨, 칼슘 그리고 마그네슘의 평균 양은 18.014, 0.878, 4.240, 7.349 그리고 2.172 kg $ha^{-1}yr^{-1}$이었다.

• 한국토양비료학회지
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• 제31권2호
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• pp.128-136
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• 1998

토양의 질소 중 대부분은 유기태 질소이며, 아미노산은 유기태 질소의 주된 분획물이다. 부산물 비료는 토양에 유기물을 공급해 주며 부식산은 유기물의 주된 구성성분이다. 아미노산은 분해되어 유효태 질소로 전환되기 때문에 토양비옥도 측면에서 중요한 역할을 한다. 본연구에서는 제조원료가 상이한 11종류의 시관 부산물 비료로부터 부식산을 추출하고, 부식산에 함유되어 있는 아미노산의 함량 및 분포를 조사했다. 공시재료로 사용한 부산물비료의 대부분은 비료공정규격을 충족시켰으나, 일부 비료는 유기물함량이 낮고, C/N비가 너무 높아 부숙되지 않은 채 판매되고 있었다. 수피비료의 경우 부숙이 진행될수록 부식산, 훌부산 함량, ${\Delta}KogK$값이 감소되었고, 부식산/훌부산 비, RF값은 증가되어 이론과 일치했다. 부식산의 형태는 Rp형태에서 B형태로 전환되었다. 부산물비료 부식산 중 총 아미노산 함량은 1.2~5.6%였고, 이중 중성 아미노산이 0.8~4.5%로 가장 높았다. 부엽토, 톱밥, 수피등 식물성원료로 제조한 부산물비료의 경우 중성>산성>염기성 아미노산의 순서였고, 계분, 돈분등 동물성원료로 제조한 부산물비료의 경우 중성>염기성>산성 아미노산의 순서였다. 부산물비료를 비교할 때, 총 아미노산 분포는 부엽토>톱밥>돈분>계분>니토 순(順), 산성아미노산은 수피>톱밥>부엽토>니토 순(順)이었다. 염기성 아미노산 분포는 산성 아미노산과 역순이었다. 중성아미노산은 부엽토>톱밥>수피>니토의 순이었다. 수피비료의 경우, 부숙이 진행될수록 산성 아미노산함량은 증가했으나. 염기성 및 중성아미노산 분포는 감소했다. 부산물비료의 원료 및 부숙정도에 따라 아미노산의 함량 및 분포는 다름을 알 수 있었다.

• 한국환경생태학회지
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• 제25권4호
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• pp.573-580
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• 2011

월악산 국립공원 내의 굴참나무림에서 2005년 5월부터 2009년 4월까지 4년 동안 월별 낙엽 생산량과 낙엽을 통해 임상에 이입되는 영양염류의 양을 조사하였다. 2005, 2006, 2007, 2008년의 낙엽생산량은 각각 5.181, 5.372, 5.314, 5.361 ton $ha^{-1}yr^{-1}$이었으며, 4년 동안의 평균 낙엽생산량은 5.307${\pm}$0.09 ton $ha^{-1}yr^{-1}$이었다. 조사기간 동안 낙엽 구성원 중 잎, 가지, 생식기관 그리고 기타가 차지하는 비율은 각각 67.5${\pm}$1.9, 13.3${\pm}$0.8, 10.1${\pm}$0.5, 9.1${\pm}$1.2%로 잎이 차지하는 비율이 가장 높았다. 조사지소에서 4년 동안 낙엽을 통해 임상에 이입되는 질소, 인, 칼륨, 칼슘 그리고 마그네슘의 평균 이입량은 각각 44.47${\pm}$6.70, 2.50${\pm}$0.25, 12.26${\pm}$0.30, 17.23${\pm}$2.32, 9.56${\pm}$0.54 kg $ha^{-1}yr^{-1}$이었다.