• Mycobiology
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• 제48권5호
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• pp.364-372
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• 2020

To improve our understanding of the relationship between soil higher fungi (belonging to Ascomycota and Basidiomycota) and Abies koreana, we surveyed A. koreana soil fungal communities in a forest in Mt. Halla, Jeju Island, Korea by next-generation sequencing (Illumina Miseq). To confirm the soil higher fungal communities, we collected two types of soils from a defined plot: soils with dead (AKDTs) and living A. koreana (AKLTs), respectively. Soil fungi were classified into 2 phyla, 19 classes, 64 orders, 133 families, 195 genera, and 229 OTUs (895,705 sequence reads). Nonmetric multidimensional scaling (NMDS) showed significantly different soil higher fungal communities between AKDTs and AKLTs (p < .05). In addition, the saprophyte composition was significantly affected by A. koreana status (p < .05). The proportion of the mycorrhizal Clavulina spp. was different between soils with AKDTs and AKLTs, suggesting that Clavulina spp. may be a crucial soil fungal species influencing A. koreana. This study will lead to a better understanding of the ecological status of A. koreana in Mt. Halla. In addition, this study could be useful for the conservation and management of A. koreana habitats.

• 한국환경과학회지
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• 제14권4호
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• pp.367-371
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• 2005

Soil samples were collected from new-developed wetland soil ecosystem of Tamarix chinesis plantation in Chinese Yellow River Delta in different months of 2003. Soil characteristics, temporal change and spatial distribution of microbial community composition and their relationship with nitrogen turnover and circling were investigated in order to analyze and characterize the role of microbial diversity and functioning in the specific soil ecosystem. The result showed that the total population of microbial community in the studied soil was considerably low, compared with common natural ecosystem. The amount of microorganism followed as the order: bacteria> actinomycetes>fungi. Amount of actinomycetes were higher by far than that of fungi. Microbial population remarkably varied in different months. Microbial population of three species in top horizon was corrected to that in deep horizon. Obvious rhizosphere effect was observed and microbial population was significantly higher in rhizosphere than other soils due to vegetation growth, root exudation, and cumulative dead fine roots. Our results demonstrate that microbial diversity is low, while is dominated by specific community in the wetland ecosystem of Tamarix chinesi.

• 한국관개배수논문집
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• 제21권1호
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• pp.99-108
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• 2014

This study investigated the effects of NPS(non point source) pollution reduction of sediment traps through field experiments. Various sizes of 4 sediment traps were applied in a upland field located in Gunwi and assessed the infiltration and storage effects as well as NPS pollution reduction effects of this technique. The characteristics of deposited soil in the sediment traps were also analyzed including distribution of particle size, soil texture, and chemical properties. The results showed that slightly different composition of soil particle size from each sediment trap with high proportion of 0.15mm and 0.25mm ranges of soil particle diameters, while the loamy sand is the main types of deposited soils in the sediment traps. Decreased NPS pollution were observed from the water quality analysis of the samples taken from the sediment traps. Further research need to be proceeded continuously to improve this technique in order to utilize on upland fields for management of agricultural NPS pollutions.

• 한국농공학회지
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• 제45권1호
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• pp.63-73
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• 2003

The settling of the dredged soil may vary with mineral composition, grain size distribution, initial water content and salt concentration of suspension of the site. A series of settling column test was performed to investigate the behaviour of solid suspension material from dredging and reclamation. Settling mode was divided into four types from the observation of interface and settling curves of clay minerals and marine clay samples, and the relationship charts of salt concentration and the initial water content were established to use in the dredging operation with any salt concentration. The critical initial water content which was defined as a threshold of zone settling and the consolidation settling was varied with salt concentration of water and was proportional to the plasticity of soil in sea water.

• Geomechanics and Engineering
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• 제5권6호
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• pp.565-574
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• 2013

Extensive study was carried out on Clay expansive soil. This soil was silty clay and can be classified as CH. The degree of expansion was found to range from low to medium depending on the free swell and swell pressure tests. The research investigated the effect of using cement dust on swelling potential, Atterberg Limit, linear shrinkage, and mineralogical composition of expansive soil. The results showed that the swelling potential, plasticity index, linear shrinkage, and clay minerals decrease with increasing cement dust percentage. The cement dust accumulates in huge amounts as a side product in cement factories, and the disposal of this fine dust is very difficult and poses an environmental threat.

• Journal of Plant Biology
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• 제15권3호
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• pp.9-13
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• 1972

This report deals with lead and zinc contamination of roadside soil and plants caused by motor vehicles as a function of distance from the road edge. The concentrations of Pb and Zn in roadside soil and plant samples from several locations decrease regularly with increasing distance from traffic. Soil samples up to 24m distance from the road edge are contaminated with more than 12.99ppm lead, and 13.40ppm zinc. The decrease in Pb and Zn contamination with increasing distance from the road is characteristically curvilinear; the relative coefficiency of Pb and Zn with distance is -0.69, -0.48, respectively. The average contents of Pb and Zn in plants are 21.5ppm and 30.00ppm. It is suggested that the contamination is related to the composition of gasoline, motor oil and to roadside of the residues of this metals.

• 아시안잔디학회지
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• 제9권4호
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• pp.317-329
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• 1995

The study of standing crop of the ground vegetation under the coniferous stands was pursuited in regard of soil nutrients at Kwangnung plantation from May to Octoher, 1971 and 1991. The coniferous stands implied pine and larch associations of which the young stands of each as-sociation were 9~12 years and the older one 40~70 years. The larch stands were more plentiful in species than in the pine stands and the Festuca ovina and Oplismenus burmannii each were dominant species of pine and larch stands. The standing crop of pine stands is from 98.02g /$m^2$ to 385.32g /$m^2$ The standing crops of those stands showed great increase from June to August when the air temperature and rainfall were fairly high. The standing crop has correlation to total nitrogen and organic matter in the soil.

• 한국환경과학회지
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• 제11권10호
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• pp.1031-1037
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• 2002

CCA (Canonical Correspondence Analysis) was used so as to analyze the relation between vegetation and soil environment of Mankyeong river located in Jeollabuk-do. Vegetation survey consulted 1:5,000 topographical map, set up 30 plot and analyzed from June, 2001, to september, 2001. Plant communities of Mankyeong river was investigated by phytosocialogical method. The species composition of plant communities showed high correlation to soil pH, soil organic matter, $P_2$$O_5$, total nitrogen, EC, when they were analyed by CCA. According to the results of CCA hydrophyte communities were distributed in the region that high pH. But the vegetation of disturbed site and wetland plants were distributed in a good nutrients.

• Journal of Ecology and Environment
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• 제45권1호
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• pp.40-53
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• 2021

The level of soil organic carbon (SOC) fluctuates in different types of forest stands: this variation can be attributed to differences in tree species, and the variables associated with soil, climate, and topographical features. The present review evaluates the level of SOC in different types of forest stands to determine the factors responsible for the observed variation. Mixed stands have the highest amount of SOC, while coniferous (both deciduous-coniferous and evergreen-coniferous) stands have greater SOC concentrations than deciduous (broadleaved) and evergreen (broadleaved) tree stands. There was a significant negative correlation between SOC and mean annual temperature (MAT) and sand composition, in all types of forest stands. In contrast, the silt fraction has a positive correlation with SOC, in all types of tree stands. Variation in SOC under different types of forest stands in different landscapes can be due to differences in MAT, and the sand and silt fraction of soil apart from the type of forests.

• 한국토양비료학회지
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• 제13권3호
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• pp.93-97
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• 1981

4종(種)의 제주도 토양에 인산질비료(燐酸質肥料)를 시용(施用)한후 무기태인산(無機態燐酸)의 형태별(形態別) 함량변화와 수종 침출액(浸出液)에 의한 유효인산(有效燐酸) 침출량(浸出量)을 실내실험으로 조사(調査)하여 비교(比較) 검토한 결과(結果)는 다음과 같다. 1. 총인산에 대한 무기태인산(無機態燐酸)의 비율(比率)은 토양종류에 따라 달라 Al-P는 6.9-28.8%, Fe-P는 24.1~26.9%, Ca-P는 7.4~11.9% 범위이며 유효인산(有效燐酸)은 0.7-8.0%로 매우 낮았다. 2. 토양종류별로 인산(燐酸)을 시용(施用)한 후(後) 60일후(日後)에 조사(調査)한 토양인산의 형태별(形態別) 조성(組成)을 본 결과(結果) 흑색토(黑色土)에서는 Al-P>Fe-P> Ca-P, 농암갈색토(濃暗褐色土)에서는 Fe-P> Al-P> Ca-P, 암갈색토(暗褐色土)에서는 Fe-P> Ca-P> Al-P. 적황색토(赤黃色土)에서는 Fe-P> Al-P> Ca-P의 순(順)으로 나타나 토양별 차이(差異)가 있었다. 3. 5종(種)의 침출액(浸出液)으로 토양별 유효인산(有效燐酸)을 검정한 결과(結果) Bray No.2법(法)은 토양종류에 관계없이 어느 토양에서나 침출능(浸出能)이 컸으나 그 외의 방법(方法)들은 토양의 종류별(種類別)로 침출능(浸出能)이 상이(相異)하게 나타났다. 4. 유효인산(有效燐酸) 침출방법(浸出方法)과 무기태인산(無機態燐酸) 함량(含量)과의 관계에서 Bray No.2법(法)은 Ca-P와 5%수준에서, Olsen법(法)은 Al-P, Fe-P, Ca-P 및 Total-P와 각각 1%수준에서 유의(有意)한 관계를 보였다.