• 아시안잔디학회지
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• 제11권4호
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• pp.303-309
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• 1997

The investigation was cycle of aluminum of surface soil elements in dynamic grassland ecosystems at a steady state in a Zoysia japonica and a Miscanthus sinensis ecosystem in Mt. Kwanak, Korea. Average amounts of total storage for aluminum in Z japonica and M. sinensis grasslands were 8,426mg /$m^2$ and 7,849mg /$m^2$ respectively. Decay constants estimated on the base of experimental and mathematical model, were 0.04 in Z japonica grassland, and 0.08 in M. sinensis grassland. Half time to decay aluminum of litter soils were 17.33 years in Z japonica grass-land, and 8.66 years in Al. sinensis grassland. 95% decay times in Z japonica, and in M. sinensis grassland were 75.0 years and 35.0 years respectively. Needed times to lose almost all of elements in Z japonica and M. sinensis grassland were 125.0 years, and 62.50 years respectively. The metals were losed more rapidly in M. sinensis than in Z japonica grassland. The cycle of aluminum was investigated to be related with soil acidity. Key words: Cycle of aluminum, Zoysia japonica. Miscanthus sinensis, Mt. Kwanak, Decay constants, Soil acidity.

• 한국지반공학회논문집
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• 제28권3호
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• pp.45-54
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• 2012

최근 쓰레기 매립장에 널리 사용되고 있는 토목섬유는 흙과의 접촉면에서 대변형 거동 및 변형율 연화 등의 전단거동 특성을 보이는데, 이는 토목섬유-흙 접촉면에서 함수비, 연직응력, 화학적 요소의 영향 등 고유물성에 기인한다. 본 연구에서는 침출수 내의 산성 및 염기성과 같은 성분의 영향이 진동하중 상태에서 토목섬유-흙 접촉면의 전단강도 감소에 미치는 영향을 분석하였다. 이를 위하여 이미 구축된 다기능 접촉면 시험기(M-PIA)를 수정 제작하고 200일간 수침시킨 토목섬유와 흙 시료를 이용하여 진동 직접전단시험을 수행하였고, 그 결과 교란상태개념에 기초하여 화학적 인자들에 의한 토목섬유-흙 접촉면의 화학적 전단강도 감소 특성을 교란도 함수로써 확인하였다. 또한 전계방출주사현미경(FIB)을 이용하여 화학적 인자에 따른 흙입자 및 접촉면 손상의 차이를 확인하였다.

• The Korean Journal of Ecology
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• 제9권1호
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• pp.51-58
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• 1986

The decay rates of organic matter were investigated and the leaching rates were determined from the concentration distribution of N,P,K, Ca and Na in the soil profile at Pinus rigida stand on Mt. Gwan-ak and at Pseudosasa japonica stand on Odong-do. In order to determine the leaching rates θo/W wazs substituted with KL in Towner's equation. Decay rates were 0.191 at Pinus stand on Mt. Gwan-ak and 0.234 at Pseudosasa stan don Odong-do. Concentration distributions of N,P, K and Na in soil profiles were corresponed with Towner's model curve. Leaching rates determined from concentration distributions were 0.086, 0.079, 0.041, 0.029, 0.096 on Mt. Gwan-ak and 0.080, 0.056, 0.051, 0.008, 0.028 on Odong-do. The soil of Pseudosasa stand showed on the whole lower leaching rates than that of Pinus stand. The soil of Pseudosasa stand showing higher decay rate and lower leaching rates contained more concentration of each nutrient than that of Pinus stand.

• The Korean Journal of Ecology
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• 제9권1호
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• pp.79-90
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• 1986

The production and decomposition of litters and nutrient cycling of forests were studied at the pine forests such as Pinus densiflora, Pinus koraiensis, Pinus rigida, Pinus thunbergii, Abies holophylla and Larix kaempfer. The annual litter production of the P. densiflora forest was the most on Mt. Mudeung which was 620.75g/$m^2$ and the least on Mt. Halla which was 155.00g/$m^2$. The decay rate of litters was the highest at the P. densiflora forest on Mt. Mudeung which was k=0.256 and the lowest at the P. densiflora forest on Mt. Halla and A. holophylla on Mt. Jiri which were k=0.099. The half time of decomposition of litters was shortest at the P. densiflora forest on Mt. Mudeung and the longest at the P. densiflora on Mt. Halla and A. holophylla forests on Mt. Jiri. The average decay rate of the L. kaempferi forests which was k=0.204 was the highest and that of the A. holophylla forests which was k=0.122 was the lowest. The decay rate tended to decrease against increasing the altitude. The annual production of litterr, the contents of mineral nutrients and the amounts of mineral nutrients inputted into the forest soil tended to increase in proportion to the decay rate, k.

• The Korean Journal of Ecology
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• 제10권3호
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• pp.109-118
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• 1987

The production and decomposition rates of litters were studied in three mountains, Mt. Halla, Mt. So-back and Mt. Tae-back. The amounts of N, P, K, Ca and Na in the soils were measured and the relationships between the mineral nutrients and decay rates were reserched, The annual litter production was the most as $1, 077.3g/m^2$ and the least as $248.0g/m^2$ in a stand of Quercus acutissima at 820m of the Mt. So-back and at 1, 350m of the Mt. So-back among the study sites, respectively. The decay rates of litter was the highest as k=0.448 and the lowest as k=0.082 in a stand of Q. acutissima at 820m of the Mt. So-back and at 1, 450m of the Mt. Tae-back at 1, 450m of the Mt. Tae-back among the study sites. The higher altitude was, the slower the decay rates were. The annual contents of mineral nutrient and their amounts inputted into the forest soil were proportional to the decay rate of organic metters.

• The Korean Journal of Ecology
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• 제10권3호
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• pp.139-149
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• 1987

Mathematical models of the litter accumulation, decay and turnover in the grassland and forest ecosystems of equilibrium state of the annual litter production were established to analyse the decay rates of organic and inorganic constituents of the litter. Those models were validated by an application to a Phragmites longivalvis grassland in a delta of the River Nakdong. The decay constants of cold-water-soluble fractions, other carbohydrates, hot-water-soluble fractions, cellulose, crude fat, lignin and crude protein in the litter were 0.730, 0.583, 0.555, 0.505, 0.479, 0.331 and 0.310 respectively. The amount of mineral nutrients such as N. P. K. Ca and Mg returned annually to the soil were estimated to 7.09, 1.34, 2.36, 4.37 and 0.79g/m2 respectively.

• 아시안잔디학회지
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• 제11권4호
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• pp.289-294
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• 1997

The cycles of heavy metals, mercury, lead and cadmium, were investigated on in dynamic grassland ecosystems at a steady state in Zoysia japonica and Miscanthus sinensis in Mt. Kwanak, Korea. Estimates of decay constants of heavy metals based on experimental and methomatical model, were Hg 0.14, Pb 0.17 and Cd 0.41 of Z. japonica grassland, and Hg 0.33, Pb 0.13 and Cd 0.56 of M sinensis grassland. The durations of reaching half of initial amounts in Z. japonica and M. sinensis grassland, were Hg 4.95, Pb 4.07 and Cd 1.69 years, and Hg 2.10, Pb 5.33 and Cd 1.24 years respectively. Times needed for 99% decomposed were longer in Z. japonica than M. sinensis grassland. Decay velocity of constituents of surface soil layers were more rapidly in M. sinensis than Z. japonica grassland. Key words: Cycles of heavy metals, Mercury, Lead, Cadmium, Zoysia japonica. Miscanthus sineusis, Mt. Kwanak, Decay constants.

• The Korean Journal of Ecology
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• 제9권4호
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• pp.185-192
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• 1986

The production and decomposition rate of litters from the three different locations, Quercus acutissium forest at 630 m, Q. mongolica forests at 1, 005m and 1, 490 m of Mt. Dokyoo, were estimated by Olson model. The contents of N, P, K, Ca and Na in soils were measured and the relationships among them were elucidated. The amounts of litter production in Q. mangolica were the lowest, 378.96g/$m^2$ at 1, 490 m and the highest, 876.12g/$m^2$ at 1, 005 m. And the amounts of litter production in Q. acutissima at 630 m was 686.16 g/$m^2$. The decay rate of litters in Q. mongolica was the smallest, 0.123 at 1, 490 m, and the largest, 0.222 at 1, 005 m. And that in Q. acutissima was 0.169 at 630 m which was the medium rate. The production and decay rate of litters decreased with the ascending altitude. The values at 630 m were maller than those at 1, 005 m. This might be due to the fact that the tree species at 630 m was Q. acutissima was 0.169 at 630 m which was the medium rate. The production and decay rate of litters decreased with the ascending altitude. The values at 630 m was Q. acutissima which was different from Q. mongolica at 1, 005 m and 1, 490 m. The half-0life of litter decay in Q. monglica was 5, 634 years at 1, 490 m and 3.134 years at 1, 005 m. And that in Q. acutissima was 4.132 years at 630 m. The decay rates of litters were tend to be inversely proportional to the ascending altitude. The annual standing stocks of mineral and their amounts returned to the soil were proportional to the decay rate of organic matters.

• 아시안잔디학회지
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• 제9권2호
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• pp.109-117
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• 1995

An investigation was performed to reveal the relation of the production and decomposition of the Zoysia japoni ica and Miscanthus sinensis litters on Mt.Kwanak. The decay constant k of litters was as follows; k of Zoysia japonica, k=0.44, k of Miscanthus sicensis, k=0.33 The time required for the decomposition of half of the accumulated organic matter of Zoysia japonice and Miscanthus sinensis was 1.6 and 2.1 years, respectively. The amount of mineral nutrients returned annually to soil is faster in the ZQvsia japonica grassland than in the Miscanthus sinensis grassland on Mt. Kwanak. Key words: Organic rnatter synthesis, Decomposition balance.

• The Korean Journal of Ecology
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• 제27권2호
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• pp.115-120
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• 2004

Coarse woody debris (CWD, $\ge$ 5 cm in maximum diameter) is an important functional component, especially to nutrient cycling in forest ecosystems. To compare mass and nutrient dynamics of CWD in natural oak forests, a two-year study was conducted at Quercus serrata and Q. variabilis stands in Yangpyeong, Kyonggi Province. Total CWD (snag, stump, log and large branch) and annual decomposition mass (Mg/ha) were 1.9 and 0.4 for the Q. serrata stand and 7.5 and 0.5 for the Q. variabilis stand, respectively. Snags covered 72% of total CWD mass for the Q. variabilis stand and 42% for the Q. serrata stand. Most of CWD was classified into decay class 1 for both stands. CWD N and P concentrations for the Q. variabilis stand significantly increased along decay class and sampling time, except for P concentration in 2002. There were no differences in CWD N concentration for the Q. serrata stand along decay class and sampling time. However, CWD P concentration decreased along sampling time. CWD N and P contents (kg/ha) ranged from 3.5∼4.7 and 0.8∼1.3 for the Q. serrata stand to 22.8∼23.6 and 3.7∼4.7 for the Q. variabilis stand. Nitrogen and P inputs (kg/ha/yr) into mineral soil through the CWD decomposition were 0.7 and 0.3 for the Q. serrata stand and 1.6 and 0.3 for the Q. variabilis stand, respectively. The number of CWD and decay rate were main factors influencing the difference in CWD mass and nutrient dynamics between both stands.