• 한국토양비료학회지
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• 제49권4호
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• pp.355-367
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• 2016

Soil salinization refers to the buildup of salts in soil to a level toxic to plants. The major factors that contribute to soil salinity are the quality, the amount and the type of irrigation water used. The presented review discusses the different sources and causes of soil salinity. The effect of soil salinity on biological processes of plants is also discussed in detail. This is followed by a debate on the influence of salt on the nutrient uptake and growth of plants. Salinity decreases the soil osmotic potential and hinders water uptake by the plants. Soil salinity affects the plants K uptake, which plays a critical role in plant metabolism due to the high concentration of soluble sodium ($Na^+$) ions. Visual symptoms that appear in the plants as a result of salinity include stunted plant growth, marginal leaf necrosis and fruit distortions. Different strategies to ameliorate salt stress globally include breeding of salt tolerant cultivars, irrigation to leach excessive salt to improve soil physical and chemical properties. As part of an ecofriendly means to alleviate salt stress and an increasing considerable attention on this area, the review then focuses on the different plant growth promoting bacteria (PGPB) mediated mechanisms with a special emphasis on ACC deaminase producing bacteria. The various strategies adopted by PGPB to alleviate various stresses in plants include the production of different osmolytes, stress related phytohormones and production of molecules related to stress signaling such as bacterial 1-aminocyclopropane-1-carboxylate (ACC) derivatives. The use of PGPB with ACC deaminase producing trait could be effective in promoting plant growth in agricultural areas affected by different stresses including salt stress. Finally, the review ends with a discussion on the various PGPB activities and the potentiality of facultative halophilic/halotolerant PGPB in alleviating salt stress.

• 환경생물
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• 제23권4호
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• pp.383-389
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• 2005

The effect of different mulching materials on mungbean production was studied. The general objective was to assess the ecological effects of mulching materials in sustainable mungbean production. Specifically, the study aimed to determine the effects of different mulching materials on the chemical, physical and biological soil properties, on weed control and yield, and to identify mulching materials that are environmentally friendly in mungbean production. The experiment was conducted at the Fruit and Vegetables Seeds Center, Science City of $Mu/tilde{n}oz$, Nueva Ecija, Philippines from May to July 2004. The initial soil chemical properties were: pH of 6.4, 2.0 percent organic matter content, 0.10 percent total nitrogen, 22 ppm phosphorus, and 370 ppm available potassium. The soil microbial loads were $8\times10^4\;CFU\;g^{-1}$ for bacteria and $14\times10^4\;CFU\;g^{-1}$ for fungi. Mushroom spent mulch increased soil organic matter with an average of 3.13 percent, nitrogen with an average of 0.16 percent and the highest number of bacterial count with $3.4\times10^8\;CFU\;g^{-1}$. Use of mulch, except rice straw mulch, generally increased mungbean yield. The best mulching material for high yield production of mungbean was black polyethylene plastic film, although environmentally unfriendly.

• Journal of Ecology and Environment
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• 제30권1호
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• pp.39-47
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• 2007

The relationships between the cover of herbaceous species and 15 soil chemical properties (organic carbon contents, total N, available P, exchangeable K, Na, Ca and Mg, HCl-extractable Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn) in nine poorly controlled waste landfill sites in Korea were examined by correlation analysis and multiple regression equations. Species showed different patterns of correlation between their cover values and soil chemical properties. The cover of Ambrosia artemisiifolia var. elatior, Aster subulatus var. sandwicensis and Erechtites hieracifolia were negatively correlated with the contents of Fe, Mn and Ni within landfill soils. Total cover of all species in quadrats was positively correlated with the contents of Cd and negatively correlated with the contents of Mn and Fe from stepwise regression analysis with 15 soil properties. Canonical correspondence analysis demonstrated that the distribution of native and exotic plants on poorly controlled landfills was significantly influenced by the contents of Na and Ca in soils, respectively.

• 한국토양비료학회지
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• 제45권1호
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• pp.1-8
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• 2012

The thermal properties including volumetric heat capacity, thermal conductivity, thermal diffusivity, and diurnal and annual damping depths of 10 representative soil series of Korea were calculated using some measurable soil parameters based on the Taxonomical Classification of Korean Soils. The heat capacity of soils demonstrated a linear function of water content and ranged from 0.2 to $0.8cal\;cm^{-3}^{\circ}C^{-1}$ for dry and saturated medium-textured soil, respectively. A small increase in water content of the dry soils caused a sharp increase in thermal conductivity. Upon further increases in water content, the conductivity increased ever more gradually and reached to a maximum value at saturation. The transition from low to high thermal conductivity occurred at low water content in the soils with coarse texture, and at high water content in the other textures. Thermal conductivity ranged between $0.37{\times}10^{-3}cal\;cm^{-1}s^{-1}^{\circ}C^{-1}$ for dry (medium-textured) soil and $4.01{\times}10^{-3}cal\;cm^{-1}s^{-1}^{\circ}C^{-1}$ for saturated (medium/coarse-textured) soil. The thermal diffusivity initially increased rapidly with small increases in water content of the soils, and then decreased upon further increases in the soil-water content. Even in an extreme soil with the highest diffusivity value ($1.1{\times}10^{-2}cm^2s^{-1}$), the daily temperature variation did not penetrate below 70 cm soil depth and the yearly variation not below 13.4 m as four times of damping depths.

• Applied Biological Chemistry
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• 제41권6호
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• pp.451-456
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• 1998

지속적농업을 위한 고성능토양을 개발하기 위하여 방울토마토를 공시작물로 계분 및 돈분퇴비를 3년간 연용하면서 방울토마토의 생육 및 수량, 그리고 연용후 토양이화학성을 조사하였다. 계분 및 돈분퇴비의 사용량과 시용 횟수가 증가할수록 토마토의 생육량 및 과실수량은 유의성 있게 증가하였으며, 뚜렷한 경향은 없으나 대체로 과실의 당도와 과실 개체당 중량 역시 증가하는 경향을 보였다. 그러나 계분 및 돈분퇴비만 사용할 경우 가비중과 경도는 현저히 낮고 공극율은 높았으며, 유기물과 치환성 칼륨의 함량은 높은 반면 치환성 칼슘의 함량이 낮아 일부 토양의 물리성과 화학성이 적정범위에 미달하거나 초과하는 불균형이 나타났다. 결론적으로 퇴비와 화학비료의 조화있는 활용을 통한 지력증진이 필요하다.

• 한국토양비료학회지
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• 제47권2호
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• pp.120-126
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• 2014

An accurate analysis of nutrient balance in different cropping systems is necessary for improving soil fertilities, causing higher crop yields and quality. This study was carried out to investigate the nutrient balance, changes in soil properties, and their effects on crop yield in long-term field cultivation under mono- and rotation-cropping systems (MCS and RCS, respectively). The analytical results of the soil properties showed that the application of mineral fertilizers alone in the MCS leads the reduction of soil CEC, exchangeable Ca, and microbial biomass C and N. Compared with the MCS of soybean, the RCS of soybean and barley significantly improved the soil properties, which increased crop yield. It might be due to the barley residue added to the RCS soil. Mean nutrient balances for 4 years were -55.9 kg N, +34.7 kg $P_2O_5$, and -0.3 kg $K_2O$ $ha^{-1}$ for the MCS and +19.7 kg N, +107.4 kg $P_2O_5$, and -48.6 kg $K_2O$ $ha^{-1}$ for the RCS, respectively. These nutrient imbalances mean that conventional fertilizer recommendations were inadequate for maintaining soil nutrient balance. From these results, we can conclude that the crop rotation may change comprehensive physical, chemical, and biological soil properties. These changes could affect the nutrient balance and then the crop yield.

• 한국환경복원기술학회지
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• 제8권6호
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• pp.59-68
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• 2005

This study was carried out to investigate soil properties, ordination, and vegetation of the coastal sand dune in Sinduri, Taean-Gun. 1. The Orobanche coerulescens and Ixeris repens that are a peculiar species were found in Sinduri coastal sand dune and the Salix purpurea var. japonica that is an endemic species of korea was found in that place. The plant communities was categorized into seven groups, such as Rosa rugosa community, Vitex rotundifolia communit, Carex kobomugi community, Imperata cylndrica var. koenigii community, Carex pumila community, Artemisia capillaris community, and Calamagrostis epigeios community. 2. The soil organic matter, total nitrogen, available phosphorous concentrations, and cation exchange capacity were lower in the study sites than in forest soil of seashore. There was little difference in soil exchangeable Ca, Mg, and K concentrations between in the study site and in the forest soil of seashore. The soil pH was ranged from 5.69 to 7.63. The soil texture in the study site was sand or loamy sand. 3. The results of the correlation between Sinduri coastal sand dune community and environmental factor are as follows; the soil pH was the most effect to the community distribution, and CEC, total nitrogen, soil organic matter, and the amount of silt in soil have some correlation with community distribution. 4. The results of the correlation between Sinduri coastal sand dune community and soil characteristics are as follows; the Calamagrostis epigeios community was found in area that have high soil moisture content; the Rosa rugosa community was found in area that have high soil CEC, organic matter concentration, and total nitrogen concentration, and low soil pH; the Vitex rotundifolia community, Carex kobomugi community, and Artemisia capillaris community were found in area that have low soil CEC, organic matter concentration, and total nitrogen concentration, and high soil pH; the Imperata cylndrica var. koenigii community and Carex pumila community were found in area that have medium soil CEC, organic matter concentration, total nitrogen concentration, and soil pH.

• Journal of Applied Biological Chemistry
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• 제42권1호
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• pp.34-39
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• 1999

In search of a method to achieve sustainable agricultural practices, a trickling filter was employed for the piggery wastewater treatment, where rice straw was the support medium in place of more commonly used materials. The filtrate from the trickling filter were applied to a soil, on which orchard grass (Dactylic glomerata L.) was grown followed by amendment of the treated straw medium. Orchard grass was cut twice, and growth parameters and yields were measured. Soil chemical properties before and after harvesting orchard grass were analyzed. Development of the forage crop was greatly enhanced by the application of the filtrate in terms of fresh weight, dry weight, and the absorption of nutrients. Better growth and higher nutrient uptake were found in the second cutting of the orchard grass. Organic matter content, ionic intensity, exchangeable cations, and phosphate of the soil increased with the application of the filtrate. The relative high concentrations of salts in the piggery trickling filtrate, expressed in electrical conductivity and content of sodium, exerted no detrimental effect on the crop and soil.

• 한국토양환경학회지
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• 제3권2호
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• pp.31-39
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• 1998

오염지역과 비오염지역으로부터 채집한 토양에서 토양의 습도, 유기물의 함량, 토양산도 등 물리적인 특징과 토양미생물의 분포와 같은 생물학적인 특징이 조사되었다. 지역에 따른 유기물의 함량과 토양산도는 큰 차이를 나타내었으나, 식물군락에 의한 토양수분과 유기물 함량의 차이점은 발견할 수 없었다. 토양의 산도는 미생물의 분포수와 상관관계를 나타내었다. 이러한 것은 식물이 자라는 토양에 변이를 주는 것으로 산성비와 관련이 있는 것으로 추정된다.

• 유기물자원화
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• 제13권1호
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• pp.79-89
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• 2005

유기성폐기물 및 토양미생물을 이용하여 산불로 훼손된 산림토양을 생태적으로 복원하기 위한 일환으로 동해안 지역에서 발생한 산불토양의 물리화학적 환경요인 및 생물학적 특성을 분석하였다. 토양 시료는 산불의 영향을 받지 않은 정상토양(US), 산불 후 자연적으로 복원된 토양(NS)과 산불 후 인위적인 복원이 시도된 토양(AS) 등, 세 지역의 표토와 심토를 이용하였다. 모든 토양 시료는 사질토가 우세한 pH5.34~5.78의 산성 토양이었으며, 함수량은 정상토양에서 높게 나타났고 자연복원지와 인위복원지에서는 표토의 함수량이 심토보다 낮았다. 총 유기물량과 수용성 당량은 정상토양에서 특히 높았으며, 전체적으로 심토보다 표토에서 높게 나타났다. 토양 종속영양세균의 군집크기는 정상토양의 표토 (UST)와 자연복원지 심토(NSS)에서 크게 나타났으며, 탈수소효소, 섬유소 분해효소, 산성 인산 분해효소의 활성도는 정상토양에서 높게 나타났다. 미생물 작용의 1차지표가 되는 탈수소효소의 활성도는 함수량과 0.902 (P<0.05)의 높은 상관관계를 보였다.